From e170f67ad5a4373c505c41583ad99826f59479cf Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=8E=8B=E5=8D=93?= <280034816@qq.com> Date: Mon, 23 May 2016 19:57:33 +0800 Subject: [PATCH 01/23] =?UTF-8?q?=E6=A0=A1=E5=AF=B9?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 校对😂 --- ... Introduction to iOS, Xcode, and Swift.srt | 4 +- subtitles/2. Applying MVC.srt | 2 +- ...3. More Swift and Foundation Framework.srt | 46 +++++++++---------- 3 files changed, 26 insertions(+), 26 deletions(-) diff --git a/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt b/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt index 20f6dc4..94cb09a 100644 --- a/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt +++ b/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt @@ -5050,7 +5050,7 @@ s digit. Comma digit. 1013 00:50:25,256 --> 00:50:27,790 This is what it would look like in C. For example, -这就看起来像是C语音 +这就看起来像是C语言 1014 00:50:27,792 --> 00:50:31,327 @@ -6851,7 +6851,7 @@ Okay, why don't we need that? Because false can only be 1374 01:09:09,613 --> 01:09:15,750 a Bool, so Swift can infer that the type of this is Bool. -因为false 只能是个Bool 型。所以Swift 可以推倒它就是个Bool 型 +因为false 只能是个Bool 型。所以Swift 可以推导它就是个Bool 型 1375 01:09:15,886 --> 01:09:19,821 diff --git a/subtitles/2. Applying MVC.srt b/subtitles/2. Applying MVC.srt index 3bf3a56..4d56d28 100644 --- a/subtitles/2. Applying MVC.srt +++ b/subtitles/2. Applying MVC.srt @@ -6631,7 +6631,7 @@ I'm gonna cut, and I'm gonna paste it right in here. Okay? 1328 01:08:39,672 --> 01:08:43,407 Now, I can't quite do that. I have to do two things. One, I -实习上我不能直接这样，还有两件事要做 +实际上我不能直接这样，还有两件事要做 1329 01:08:43,409 --> 01:08:47,911 diff --git a/subtitles/3. More Swift and Foundation Framework.srt b/subtitles/3. More Swift and Foundation Framework.srt index f76cd2d..7a04849 100644 --- a/subtitles/3. More Swift and Foundation Framework.srt +++ b/subtitles/3. More Swift and Foundation Framework.srt @@ -1,4 +1,4 @@ -1 +1 00:00:06,000 --> 00:00:09,060 Stanford University. >> Okay, 斯坦福大学 @@ -620,12 +620,12 @@ a simple way to have a default value in case an optional is 124 00:06:38,920 --> 00:06:43,490 nil. All right so let's talk about another thing, tuples. -继续介绍另一东西，元祖。 +继续介绍另一东西，元组。 125 00:06:43,490 --> 00:06:47,960 All right tuples are a type, okay? In Swift they're really, -元祖是一种类型，在 Swift 中它们非常酷 +元组是一种类型，在 Swift 中它们非常酷 126 00:06:47,960 --> 00:06:51,670 @@ -645,7 +645,7 @@ you can use it anywhere you can use a type, a tuple can be 129 00:06:56,840 --> 00:07:01,640 used anywhere types are valid, okay? So, here's an example. -一个元祖在任何地方使用都是可以的，好的。这里有一个例子 +一个元组在任何地方使用都是可以的，好的。这里有一个例子 130 00:07:01,640 --> 00:07:06,010 @@ -655,22 +655,22 @@ I'm going to create x, okay? This let x, x is a constant. 131 00:07:06,020 --> 00:07:09,950 It's type is a tuple, with a string, int, and -这是一个元祖类型，含有 string, int, 和 double +这是一个元组类型，含有 string, int, 和 double 132 00:07:09,950 --> 00:07:14,020 double. So, even though tuple has the sound, to, in it, -尽管元祖听起来有 two 的声音 +尽管元组听起来有 two 的声音 133 00:07:14,020 --> 00:07:17,190 it's just not two things. Any number of things can be in -但并不是他有只有两个东西。一个元祖里面可以有任何数量的东西 +但并不是他有只有两个东西。一个元组里面可以有任何数量的东西 134 00:07:17,190 --> 00:07:22,460 a tuple okay? So x there is a tuple with string int and -好的，所以 x 是一个含有 string int double 的元祖 +好的，所以 x 是一个含有 string int double 的元组 135 00:07:22,470 --> 00:07:24,700 @@ -685,7 +685,7 @@ which is just parenthesis, a string, an int, and a double, 137 00:07:28,240 --> 00:07:33,070 okay? Now how do I get those values out of the tuple? -好的。现在我该如何从这个元祖里面获得值呢 +好的。现在我该如何从这个元组里面获得值呢 138 00:07:33,080 --> 00:07:34,480 @@ -715,7 +715,7 @@ assign them to word, number, and value, which are gonna 143 00:07:48,320 --> 00:07:51,330 be local variables in this context, okay? Now, if you -它们会在这个上下文里得到蹦迪变量。好的，现在 +它们会在这个上下文里得到本地变量。好的，现在 144 00:07:51,330 --> 00:07:55,730 @@ -730,7 +730,7 @@ equal x, the compiler will complain, because word, comma, 146 00:08:00,170 --> 00:08:04,040 number can't match a string in double tuples. Okay? So -应为 word, number 无法和元祖里的 double 关键字匹配。好的 +应为 word, number 无法和元组里的 double 关键字匹配。好的 147 00:08:04,040 --> 00:08:07,610 @@ -740,7 +740,7 @@ this particular syntax is just putting names on the things in 148 00:08:07,610 --> 00:08:11,510 the Tuple so you can use them, so now you can print them out. -你可以这样使用元祖，所以你现在可以把它们打印出来了 +你可以这样使用元组，所以你现在可以把它们打印出来了 149 00:08:11,510 --> 00:08:12,580 @@ -760,12 +760,12 @@ and value would be of type double. Okay, 152 00:08:18,120 --> 00:08:22,090 another way to do it is when you create the tuple, okay, -另一种这么做的方法是，当你在生成元祖时，好的。 +另一种这么做的方法是，当你在生成元组时，好的。 153 00:08:22,090 --> 00:08:24,830 you can name each of the things in the tuple. So -你可以为元祖里的每个东西命名。 +你可以为元组里的每个东西命名。 154 00:08:24,830 --> 00:08:31,070 @@ -775,7 +775,7 @@ here I'm letting x, this time be w: String i: Int v: Double. 155 00:08:31,070 --> 00:08:34,640 I'm giving the names w, i and v to the things inside -我在元祖里面分别起了几个名字叫 w，i 和 v +我在元组里面分别起了几个名字叫 w，i 和 v 156 00:08:34,640 --> 00:08:37,240 @@ -790,7 +790,7 @@ the version above. But now if I want to get at the values, 158 00:08:40,340 --> 00:08:45,550 I can just say x.w, x.i, and x.v to get at the tuple -我可以直接说 x.w，x.i，还有 x.v 来获得元祖中的值 +我可以直接说 x.w，x.i，还有 x.v 来获得元组中的值 159 00:08:45,550 --> 00:08:48,250 @@ -800,12 +800,12 @@ values. See the difference between those two cases? 160 00:08:48,250 --> 00:08:51,090 One, you're kind of naming it when you declare the tuple, -一种，在你声明元祖的时候定义一种命名 +一种，在你声明元组的时候定义一种命名 161 00:08:51,090 --> 00:08:53,920 the other one is you're taking a tuple that you got and -另一种是你拿到一个元祖 +另一种是你拿到一个元组 162 00:08:53,920 --> 00:08:56,620 @@ -905,7 +905,7 @@ So tuples are perfectly valid return values, okay? So 181 00:09:50,010 --> 00:09:52,910 you can return multiple things from functions. All right, -所以你可以从这可方法返回多个值 +所以你可以从函数返回多个值 182 00:09:52,920 --> 00:09:56,850 @@ -1380,7 +1380,7 @@ it doesn't want to actually make a copy. Okay? 276 00:15:08,430 --> 00:15:11,430 It gets another pointer to it but as soon as you try to -在你视图去改变它的时候 +在你试图去改变它的时候 277 00:15:11,430 --> 00:15:15,370 @@ -1660,7 +1660,7 @@ you're gonna choose classes, okay? Anything big is almost 332 00:17:45,090 --> 00:17:50,660 certainly gonna use the class, all right? Okay. -任何大型的东西坑定会使用类，对吗？ +任何大型的东西肯定会使用类，对吗？ 333 00:17:50,660 --> 00:17:53,730 @@ -1957,7 +1957,7 @@ possible to mark a method or a property final in which case 392 00:21:18,200 --> 00:21:21,270 no one can subclasses. Okay, there won't be a list, -一个子类不能再类前放 override +一个子类不能在类前放 override 393 00:21:21,270 --> 00:21:24,740 @@ -2246,7 +2246,7 @@ In Swift we're only just scratching the surface so 450 00:24:27,890 --> 00:24:31,220 far of what they can do. But one really cool thing about -但是有一件关于它的很酷低是 +但是有一件关于它的很酷的是 451 00:24:31,230 --> 00:24:35,830 From 93ac180d517d48653de6437738f20d680bed9b68 Mon Sep 17 00:00:00 2001 From: X140Yu Date: Mon, 4 Jul 2016 09:29:31 +0800 Subject: [PATCH 02/23] add subtitles 13-18 --- subtitles/13. NSTimer and Animation.srt | 6000 +++++++++++++++ subtitles/14. Animation and Core Motion.srt | 5492 ++++++++++++++ ...pplication Lifecycle, Alerts, CloudKit.srt | 6580 +++++++++++++++++ subtitles/16. Notifications and CloudKit.srt | 4924 ++++++++++++ .../17. Segues, Core Location, and MapKit.srt | 6108 +++++++++++++++ subtitles/18. Persistence.srt | 5536 ++++++++++++++ 6 files changed, 34640 insertions(+) create mode 100644 subtitles/13. NSTimer and Animation.srt create mode 100644 subtitles/14. Animation and Core Motion.srt create mode 100644 subtitles/15. Application Lifecycle, Alerts, CloudKit.srt create mode 100644 subtitles/16. Notifications and CloudKit.srt create mode 100644 subtitles/17. Segues, Core Location, and MapKit.srt create mode 100644 subtitles/18. Persistence.srt diff --git a/subtitles/13. NSTimer and Animation.srt b/subtitles/13. NSTimer and Animation.srt new file mode 100644 index 0000000..329bca2 --- /dev/null +++ b/subtitles/13. NSTimer and Animation.srt @@ -0,0 +1,6000 @@ +1 +00:00:00,001 --> 00:00:03,602 +[MUSIC] + +2 +00:00:03,604 --> 00:00:08,507 +Stanford University. >> Okay, well, welcome + +3 +00:00:08,509 --> 00:00:13,946 +to Lecture 13 of Stanford CS193P spring of 2016. Today, + +4 +00:00:13,948 --> 00:00:18,117 +we're gonna be talking about animation, + +5 +00:00:18,119 --> 00:00:21,754 +primarily. I'm actually gonna show you a little class called + +6 +00:00:21,756 --> 00:00:25,290 +NSTimer first, which we really don't use for animations. But + +7 +00:00:25,292 --> 00:00:28,527 +when we're doing animations surprisingly, we end up using + +8 +00:00:28,529 --> 00:00:30,896 +NSTimer sometimes. Not for the animation itself, + +9 +00:00:30,898 --> 00:00:34,266 +but just because animation is timing-based thing, and + +10 +00:00:34,268 --> 00:00:36,869 +NSTimer obviously is a timing-based class. + +11 +00:00:36,871 --> 00:00:38,771 +And then we're gonna dive right into animation, and + +12 +00:00:38,773 --> 00:00:42,441 +there's lots and lots of mechanisms for animation + +13 +00:00:42,443 --> 00:00:45,244 +in iOS, and I'm only gonna show you, you know, two or + +14 +00:00:45,246 --> 00:00:48,614 +three different ones. I'll talk a little bit about what, + +15 +00:00:48,616 --> 00:00:52,184 +what things there are, but I'm only gonna dive into a few of + +16 +00:00:52,186 --> 00:00:55,687 +them. And one of them, the simulated physics version, + +17 +00:00:55,689 --> 00:00:59,158 +I will get started on the slides today at the end, but + +18 +00:00:59,160 --> 00:01:01,393 +I won't make it all the way through, and + +19 +00:01:01,395 --> 00:01:04,963 +I'll just continue in the next lecture, okay. All right, + +20 +00:01:04,965 --> 00:01:07,566 +so let's take this little detour and talk about NSTimer. + +21 +00:01:07,568 --> 00:01:12,471 +NSTimer is a very simple little class that allows + +22 +00:01:12,473 --> 00:01:16,909 +you to call a method periodically, okay. + +23 +00:01:16,911 --> 00:01:17,976 +And you could either have it + +24 +00:01:17,978 --> 00:01:19,645 +repeating where it's calling it over and + +25 +00:01:19,647 --> 00:01:22,548 +over every certain amount of time, or you can actually just + +26 +00:01:22,550 --> 00:01:25,417 +have it call it once sometime in the future. Okay, so + +27 +00:01:25,419 --> 00:01:29,121 +it's a way to set up a time or to call a method. It couldn't + +28 +00:01:29,123 --> 00:01:31,924 +really be simpler than that. Again, we're not gonna + +29 +00:01:31,926 --> 00:01:34,460 +use it for animation, you know, things moving around and + +30 +00:01:34,462 --> 00:01:35,294 +stuff. There's other mechanisms for + +31 +00:01:35,296 --> 00:01:38,630 +doing that. But you're gonna see from the demo I do today, + +32 +00:01:38,632 --> 00:01:41,200 +wha, where NSTimer kind of can come in and be used. + +33 +00:01:41,202 --> 00:01:43,702 +It's actually quite useful in a lot of situations. + +34 +00:01:43,704 --> 00:01:48,307 +It's not a real time timer, you know? This is not a real + +35 +00:01:48,309 --> 00:01:52,144 +time operating system. You got that main queue. Other blocks + +36 +00:01:52,146 --> 00:01:54,179 +might be executing off that main queue, and so + +37 +00:01:54,181 --> 00:01:57,549 +the timer's trying to execute, but it can't cuz it's busy. + +38 +00:01:57,551 --> 00:02:00,319 +So it could be off a little bit but it's generally + +39 +00:02:00,321 --> 00:02:05,457 +going to try to set this, call this method when you say. + +40 +00:02:05,659 --> 00:02:08,227 +The timer's built on a mechanism in iOS which I'm not + +41 +00:02:08,229 --> 00:02:11,296 +gonna talk about at all in this class, called run loops. + +42 +00:02:11,298 --> 00:02:14,433 +For the main queue, there's a run loop set up for you, so + +43 +00:02:14,435 --> 00:02:18,570 +NSTimer always works on the main queue. For other queues, + +44 +00:02:18,572 --> 00:02:21,106 +you know, you may or may not have a run loop. You might + +45 +00:02:21,108 --> 00:02:24,209 +have to set up your own run loop, etc, so for the purposes + +46 +00:02:24,211 --> 00:02:27,813 +of this class, just assume NSTimer is a main queue thing. + +47 +00:02:27,815 --> 00:02:30,082 +Of course, when a timer goes off and calls a method, + +48 +00:02:30,084 --> 00:02:33,352 +you could dispatc_async to another queue in that method, + +49 +00:02:33,354 --> 00:02:35,821 +that's fine. It is just that the actual firing of + +50 +00:02:35,823 --> 00:02:39,091 +the timer, that has to be happening in the main queue, + +51 +00:02:39,093 --> 00:02:40,459 +for the purposes of this class. + +52 +00:02:40,461 --> 00:02:42,561 +Okay, so what's the main method + +53 +00:02:42,563 --> 00:02:45,831 +look like in NSTimer that does this? This is it. + +54 +00:02:45,833 --> 00:02:47,866 +Say I just scheduled timer with time interval. + +55 +00:02:47,868 --> 00:02:49,368 +Notice that it's a class method, right, + +56 +00:02:49,370 --> 00:02:52,404 +a static method on the class. So you invoke this by saying + +57 +00:02:52,406 --> 00:02:56,175 +NSTimer.scheduledTimeWithTime- Interval. And you just specify + +58 +00:02:56,177 --> 00:02:58,544 +how many seconds from now you want this timer to go off for + +59 +00:02:58,546 --> 00:03:02,147 +the first time, and then you specify a target and selector. + +60 +00:03:02,149 --> 00:03:04,750 +That's the method in the object that you want to be + +61 +00:03:04,752 --> 00:03:07,352 +called. You got this user info, that's basically + +62 +00:03:07,354 --> 00:03:10,656 +a cookie, right? You can put anything you want in there, + +63 +00:03:10,658 --> 00:03:11,590 +some context, whatever, + +64 +00:03:11,592 --> 00:03:12,524 +you can leave it nil if you want. + +65 +00:03:12,526 --> 00:03:16,061 +And then repeat is whether it's going to go off again in + +66 +00:03:16,063 --> 00:03:18,997 +this many seconds, at the beginning there, and + +67 +00:03:18,999 --> 00:03:22,167 +then just keep going off, over and over and over. + +68 +00:03:22,169 --> 00:03:26,438 +So it couldn't really be simpler than that. So + +69 +00:03:26,440 --> 00:03:28,240 +here's an example of calling it. All right, + +70 +00:03:28,242 --> 00:03:31,810 +I'm calling it for it to go off in two seconds there. + +71 +00:03:31,812 --> 00:03:35,747 +You see? Two seconds and I'm gonna call a method in myself + +72 +00:03:35,749 --> 00:03:37,683 +called fire. It has one argument. + +73 +00:03:37,685 --> 00:03:40,452 +We'll talk about that what that argument is in a second. + +74 +00:03:40,454 --> 00:03:43,322 +And then here I'm not passing any context or + +75 +00:03:43,324 --> 00:03:44,022 +cookie or whatever right there, + +76 +00:03:44,024 --> 00:03:46,792 +just nil. And this one's gonna be re, repeating. So every two + +77 +00:03:46,794 --> 00:03:50,195 +seconds this method, fire, is going to be invoked in self. + +78 +00:03:50,197 --> 00:03:53,632 +And so let's go ahead and look at fire with this argument + +79 +00:03:53,634 --> 00:03:55,100 +NSTimer in there. Here it is. + +80 +00:03:55,102 --> 00:03:59,571 +You remember from the selector syntax up here, this hashtag, + +81 +00:03:59,573 --> 00:04:02,975 +or pound sign, whatever, hashtag we call it now, + +82 +00:04:02,977 --> 00:04:07,212 +[LAUGH] pound sign selector. Fire, see this little + +83 +00:04:07,214 --> 00:04:10,115 +under bar colon right there means it has an argument. And + +84 +00:04:10,117 --> 00:04:14,620 +that argument, for NStimer is always the timer itself, okay? + +85 +00:04:14,622 --> 00:04:18,056 +So that's the timer that is sending you this fire + +86 +00:04:18,058 --> 00:04:18,257 +method down here. And + +87 +00:04:18,259 --> 00:04:21,226 +inside of the implementation of this fire method, you can + +88 +00:04:21,228 --> 00:04:24,596 +get this cookie that you gave it up here where it's, + +89 +00:04:24,598 --> 00:04:26,498 +now it's nil but if I put a cookie up there, + +90 +00:04:26,500 --> 00:04:31,903 +I can get it back by accessing the userInfo bar on NSTimer, + +91 +00:04:31,905 --> 00:04:34,906 +see? So that's how you get the cookie back. Cuz remember this + +92 +00:04:34,908 --> 00:04:36,842 +timer is going on some number of seconds or + +93 +00:04:36,844 --> 00:04:39,811 +even minutes later, and you might want that timer to + +94 +00:04:39,813 --> 00:04:42,447 +get that cookie back at that time. Okay, + +95 +00:04:42,449 --> 00:04:44,916 +now what if you have a repeating timer and + +96 +00:04:44,918 --> 00:04:48,253 +you wanna stop it? How do you do that? You call this method + +97 +00:04:48,255 --> 00:04:50,922 +on the timer called invalidate. Now a little bit + +98 +00:04:50,924 --> 00:04:53,625 +of a warning, if you call invalidate on a timer, + +99 +00:04:53,627 --> 00:04:55,093 +that timer is no longer valid, and + +100 +00:04:55,095 --> 00:04:57,663 +you should not do anything with it. You can't restart it, + +101 +00:04:57,665 --> 00:04:59,731 +really. There's nothing you can do with it. And + +102 +00:04:59,733 --> 00:05:03,368 +so it's usually a pretty bad idea to have a strong pointer + +103 +00:05:03,370 --> 00:05:06,605 +to an NSTimer, okay? Because you've got the strong pointer, + +104 +00:05:06,607 --> 00:05:09,708 +you invalidate it. Now you've got a strong pointer to + +105 +00:05:09,710 --> 00:05:10,876 +something that's invalid. + +106 +00:05:10,878 --> 00:05:13,045 +So it's much better to make your pointers to NSTimers + +107 +00:05:13,047 --> 00:05:16,415 +be weak. And when you do that, if you hit invalidate, + +108 +00:05:16,417 --> 00:05:18,784 +no one will have a strong pointer to it anymore. And + +109 +00:05:18,786 --> 00:05:22,988 +it'll leave the heap, and your weak variable will get set + +110 +00:05:22,990 --> 00:05:26,625 +to nil. So I recommend using weak pointers to NSTimers. Or + +111 +00:05:26,627 --> 00:05:31,630 +not having any at all because remember every time it fires, + +112 +00:05:31,632 --> 00:05:37,069 +you get this timer passed back to you as the argument if you + +113 +00:05:37,071 --> 00:05:40,105 +want it. Okay, tolerance. + +114 +00:05:40,107 --> 00:05:44,509 +So you can specify in the timer a tolerance, and that's + +115 +00:05:44,511 --> 00:05:49,348 +basically how much you're willing to accept some slop in + +116 +00:05:49,350 --> 00:05:52,017 +its calculation of when it goes off, + +117 +00:05:52,019 --> 00:05:54,853 +okay? So here I'm talking about an example where you + +118 +00:05:54,855 --> 00:05:55,854 +have a timer goes off once a minute. + +119 +00:05:55,856 --> 00:05:58,323 +You set the tolerance to ten, which is in seconds, + +120 +00:05:58,325 --> 00:06:01,927 +and that means if it goes off after a minute, that's fine, + +121 +00:06:01,929 --> 00:06:03,662 +a minute and three seconds from now. + +122 +00:06:03,664 --> 00:06:05,864 +Yeah, okay, a minute and 7 seconds, fine, but + +123 +00:06:05,866 --> 00:06:08,834 +a minute and 20 seconds, that's too long, all right. + +124 +00:06:08,836 --> 00:06:10,402 +And so why would you want this tolerance? + +125 +00:06:10,404 --> 00:06:12,437 +Well, because other things are going on in the system, and + +126 +00:06:12,439 --> 00:06:15,273 +if you really don't care about getting it right on time, + +127 +00:06:15,275 --> 00:06:17,342 +then maybe the system can be more efficient about how it's + +128 +00:06:17,344 --> 00:06:21,947 +using its processor and other resources during that time. + +129 +00:06:21,949 --> 00:06:25,951 +Okay, and notice that this tolerance does not cause + +130 +00:06:25,953 --> 00:06:29,187 +drift. So if the first time it goes off, it goes off a minute + +131 +00:06:29,189 --> 00:06:33,558 +and seven seconds after, the next time it's gonna go off, + +132 +00:06:33,560 --> 00:06:36,161 +try to go off two minutes from the beginning. And + +133 +00:06:36,163 --> 00:06:37,729 +the next time, three minutes from the beginning, + +134 +00:06:37,731 --> 00:06:41,133 +you see what I mean, it's not drifting. If it's late on one, + +135 +00:06:41,135 --> 00:06:43,769 +it's doesn't start being late on the next one. + +136 +00:06:44,538 --> 00:06:46,037 +All right, so let's do a demo of this, so + +137 +00:06:46,039 --> 00:06:50,075 +you can see it in action. What I'm gonna do here is I'm gonna + +138 +00:06:50,077 --> 00:06:54,112 +take our old friend FaceIt, okay, remember FaceIt there, + +139 +00:06:54,114 --> 00:06:57,883 +and we're gonna make it so his eyes blink, okay, and + +140 +00:06:57,885 --> 00:07:01,787 +we're gonna do that using a timer. So + +141 +00:07:01,789 --> 00:07:04,222 +it's pretty straightforward actually to do this. + +142 +00:07:04,224 --> 00:07:07,192 +I'm gonna use this opportunity to teach you something else. + +143 +00:07:07,194 --> 00:07:09,761 +Okay, I always try to do that. Which is, + +144 +00:07:09,763 --> 00:07:13,331 +what if I had this MVC right here. If you look at this MVC, + +145 +00:07:13,333 --> 00:07:16,067 +if you look at the identity inspector for + +146 +00:07:16,069 --> 00:07:19,604 +it, you can see that its class, of course, + +147 +00:07:19,606 --> 00:07:20,439 +is FaceViewController. + +148 +00:07:20,441 --> 00:07:22,374 +Right, you remember our FaceViewController? + +149 +00:07:22,376 --> 00:07:24,176 +It's got all this stuff our face views. + +150 +00:07:24,178 --> 00:07:27,078 +We got all that those gesture recognizer, + +151 +00:07:27,347 --> 00:07:28,079 +all this stuff remember that? So + +152 +00:07:28,081 --> 00:07:30,749 +that makes sense that that's what the controller is for + +153 +00:07:30,751 --> 00:07:34,219 +this. What if I wanted to put all my blinking stuff in + +154 +00:07:34,221 --> 00:07:37,456 +another class? In other words, I didn't want to put blinking + +155 +00:07:37,458 --> 00:07:39,624 +in with all this other FaceViewController, + +156 +00:07:39,626 --> 00:07:42,127 +okay? In other words, what if I wanted a blinking + +157 +00:07:42,129 --> 00:07:45,831 +FaceViewController? Okay, well, you can use inheritance, + +158 +00:07:45,833 --> 00:07:48,633 +this is object-oriented programming. It's not uncommon + +159 +00:07:48,635 --> 00:07:52,103 +to create a subclass of another MVC's controller to + +160 +00:07:52,105 --> 00:07:54,806 +create a controller you want for your MVC. + +161 +00:07:54,808 --> 00:07:56,942 +And that's exactly what I'm gonna do. Okay, + +162 +00:07:56,944 --> 00:07:59,878 +I'm gonna create a new controller here, new File. + +163 +00:07:59,880 --> 00:08:03,582 +Okay, to iOS source, it's a Cocoa Touch Class. But + +164 +00:08:03,584 --> 00:08:07,252 +instead of the subclass being of some UI kit class here, + +165 +00:08:07,254 --> 00:08:12,390 +it's gonna be a subclass of my class, FaceViewController. + +166 +00:08:12,392 --> 00:08:17,329 +Okay, and I'm gonna call it BlinkingFaceViewController, + +167 +00:08:17,331 --> 00:08:19,865 +all right? So, here it is, it's creating it, + +168 +00:08:19,867 --> 00:08:22,300 +putting in all the regular places where it puts it. + +169 +00:08:22,302 --> 00:08:24,402 +Here it is, I don't need any of this stuff, so + +170 +00:08:24,404 --> 00:08:26,037 +I'll get out that out of there. So + +171 +00:08:26,039 --> 00:08:27,939 +I've got this BlinkingFaceViewController, + +172 +00:08:27,941 --> 00:08:30,542 +it's a subclass of FaceViewController. And + +173 +00:08:30,544 --> 00:08:33,278 +in my storyboard, if I went to this and + +174 +00:08:33,280 --> 00:08:35,046 +changed in the identity inspector for + +175 +00:08:35,048 --> 00:08:38,316 +this, changed it from being a FaceViewController to being + +176 +00:08:38,318 --> 00:08:41,019 +a BlinkingFaceViewController. And hit Run, + +177 +00:08:41,021 --> 00:08:45,857 +do you think this would work? Yeah it would work, because + +178 +00:08:45,859 --> 00:08:48,393 +BlinkingFaceViewController inherits everything from + +179 +00:08:48,395 --> 00:08:51,062 +FaceViewController, so it's gonna work just as well. + +180 +00:08:51,064 --> 00:08:53,365 +Cuz, full inheritance of it. So, let's go back here and + +181 +00:08:53,367 --> 00:08:57,536 +remember what face this emotions app here does. So we + +182 +00:08:57,538 --> 00:08:59,437 +can pick our various emotions. You can see it's working + +183 +00:08:59,439 --> 00:09:02,541 +just fine to have this be a BlinkingFaceViewController. + +184 +00:09:02,543 --> 00:09:03,074 +Of course, it doesn't blink, + +185 +00:09:03,076 --> 00:09:05,644 +cuz I haven't put any blinking code in there, but + +186 +00:09:05,646 --> 00:09:08,914 +I am gonna put the blinking code in now. Okay, I'm gonna + +187 +00:09:08,916 --> 00:09:12,517 +put all that blinking code up here in this subclass. So, + +188 +00:09:12,519 --> 00:09:15,053 +the, this blinking thing is pretty simple. It basically + +189 +00:09:15,055 --> 00:09:19,891 +needs a Bool here, which is whether it's blinking or not, + +190 +00:09:19,893 --> 00:09:22,427 +we'll start it out as false, it's not blinking, and + +191 +00:09:22,429 --> 00:09:24,629 +of course every time this changes, we're need, + +192 +00:09:24,631 --> 00:09:28,900 +going to, basically need to start blinking, okay? + +193 +00:09:28,902 --> 00:09:31,636 +If someone says that, you know, if someone the, + +194 +00:09:31,638 --> 00:09:34,806 +if someone says didSet, changes this blinking thing. + +195 +00:09:34,808 --> 00:09:40,045 +So, I need a little private, oops, private var here, + +196 +00:09:40,047 --> 00:09:41,880 +startBlink, and + +197 +00:09:41,882 --> 00:09:44,282 +it's going to just have to start things blinking. And + +198 +00:09:44,284 --> 00:09:46,818 +actually, it's gonna want to look at blinking, though, and + +199 +00:09:46,820 --> 00:09:50,555 +only do the blinking if blinking is true. Okay, + +200 +00:09:50,557 --> 00:09:53,191 +if blinking is not true, it's not gonna want to do that. + +201 +00:09:53,193 --> 00:09:56,227 +Private, oops, this is not func. Private func. + +202 +00:09:56,229 --> 00:09:59,097 +[LAUGH] Okay, so inside the blinking there it's gonna want + +203 +00:09:59,099 --> 00:10:02,300 +to start blinking, we'll talk about how to do startBlink in + +204 +00:10:02,302 --> 00:10:06,471 +a second. Now sort of for the purposes of demo, + +205 +00:10:06,473 --> 00:10:09,307 +but also to talk a little bit about timers here, + +206 +00:10:09,309 --> 00:10:12,877 +I'm actually in my viewDidAppear, okay, + +207 +00:10:12,879 --> 00:10:17,649 +super.viewDidAppear(animated). I'm gonna + +208 +00:10:17,651 --> 00:10:21,186 +start myself blinking. So I'm gonna say blinking = true. + +209 +00:10:21,188 --> 00:10:23,989 +It's a little bit demoware, because you probably wouldn't + +210 +00:10:23,991 --> 00:10:25,824 +want a blinking face controller to always start + +211 +00:10:25,826 --> 00:10:28,693 +blinking as soon as it comes up. You wanna let people, this + +212 +00:10:28,695 --> 00:10:31,396 +is a public var and you wanna let them control it with that. + +213 +00:10:31,398 --> 00:10:33,965 +But it's good for the demo here and + +214 +00:10:33,967 --> 00:10:37,602 +also in viewWillDisappear, I'm gonna do the opposite and + +215 +00:10:37,604 --> 00:10:41,539 +turn it back off. And we'll talk about why I'm gonna do + +216 +00:10:41,541 --> 00:10:46,911 +that in a second. Blinking = false, okay? All right, so + +217 +00:10:46,913 --> 00:10:49,047 +we got this kind of infrastructure for + +218 +00:10:49,049 --> 00:10:49,914 +our blinking right here. + +219 +00:10:49,916 --> 00:10:51,683 +How are we actually gonna do the blinking? + +220 +00:10:51,685 --> 00:10:54,119 +Blinking is really easy. We're gonna start blink, + +221 +00:10:54,121 --> 00:10:57,455 +how do we start a blink in real life? We close our eyes, + +222 +00:10:57,457 --> 00:11:02,560 +right? So, we're gonna have our faceView.eyesOpen = false. + +223 +00:11:02,562 --> 00:11:06,931 +Okay, we just closed our eyes. And now, after a moment, + +224 +00:11:06,933 --> 00:11:09,868 +open them again. That's what we do when we blink, right? + +225 +00:11:09,870 --> 00:11:12,604 +We close them, and then pretty soon after that, + +226 +00:11:12,606 --> 00:11:12,971 +we open them back up again. + +227 +00:11:12,973 --> 00:11:16,574 +That's what a blink is, okay? So that's what we need to do. + +228 +00:11:16,576 --> 00:11:18,843 +Now before we talk about how I'm gonna do this, + +229 +00:11:18,845 --> 00:11:21,112 +let's look at faceView right here. This is interesting, + +230 +00:11:21,114 --> 00:11:24,249 +faceView, where does that come from? Anyone know where that + +231 +00:11:24,251 --> 00:11:27,886 +comes from? Yeah, inherited from this guy, + +232 +00:11:27,888 --> 00:11:31,389 +from faceViewController. If I go back to faceViewController, + +233 +00:11:31,391 --> 00:11:32,457 +here it is right here, faceView. + +234 +00:11:32,459 --> 00:11:36,961 +Notice it's not private, okay? Usually, we make our outlets + +235 +00:11:36,963 --> 00:11:39,064 +private. We didn't happen to make this one private, + +236 +00:11:39,066 --> 00:11:41,032 +might've been an oversight on my part. But + +237 +00:11:41,034 --> 00:11:43,868 +we didn't make it private. One of the interesting things + +238 +00:11:43,870 --> 00:11:47,505 +about Swift is that there's no idea of protected. How many + +239 +00:11:47,507 --> 00:11:51,409 +people know what protected means? Okay, not too many. + +240 +00:11:51,411 --> 00:11:53,611 +So, we know about private and public, right? + +241 +00:11:53,613 --> 00:11:56,548 +Private means you can only use it in this class, public means + +242 +00:11:56,550 --> 00:11:58,983 +you can use it outside the framework you're in. + +243 +00:11:58,985 --> 00:12:00,485 +Everything else in Swift is internal, + +244 +00:12:00,487 --> 00:12:02,053 +which means you can use anything, anywhere, + +245 +00:12:02,055 --> 00:12:04,989 +inside the framework you're in, including your app is kind + +246 +00:12:04,991 --> 00:12:07,792 +of like a framework. So this faceView is really available + +247 +00:12:07,794 --> 00:12:12,897 +to any class that's inside our app, okay? And, so, + +248 +00:12:12,899 --> 00:12:15,033 +that's nice, but, it would be maybe better if + +249 +00:12:15,035 --> 00:12:17,869 +there were another protection class called protected. And, + +250 +00:12:17,871 --> 00:12:22,707 +what that would mean is, only subclasses can use this thing. + +251 +00:12:22,709 --> 00:12:23,608 +Cuz, that's really what I'd like here. + +252 +00:12:23,610 --> 00:12:27,412 +FaceView, I really don't want other classes even in my app, + +253 +00:12:27,414 --> 00:12:30,014 +thinking they can start mucking with my faceView, + +254 +00:12:30,016 --> 00:12:33,752 +okay? But I want to be able to allow people to subclass. + +255 +00:12:33,754 --> 00:12:35,153 +So unfortunately can't do that, so + +256 +00:12:35,155 --> 00:12:36,988 +if you want something to be subclassable, and + +257 +00:12:36,990 --> 00:12:39,624 +it's used in a subclass, you have to leave it internal, + +258 +00:12:39,626 --> 00:12:43,995 +okay? So we're gonna leave that internal, and + +259 +00:12:43,997 --> 00:12:46,564 +that means we can use it here to open the eyes. + +260 +00:12:46,566 --> 00:12:49,134 +Or to close the eyes. Okay, so now how are we going to + +261 +00:12:49,136 --> 00:12:51,169 +do this thing where we wait a moment and open them? Well, + +262 +00:12:51,171 --> 00:12:54,372 +I'm just gonna use Timer, of course, that's why we're here! + +263 +00:12:54,374 --> 00:12:57,509 +So let's, some space here. NSTimer, it's called + +264 +00:12:57,511 --> 00:13:01,513 +ScheduledTimerWithTimeInter- val, notice there's two of + +265 +00:13:01,515 --> 00:13:04,015 +them here. See this one and this one. + +266 +00:13:04,017 --> 00:13:06,818 +We don't want to use this one, this one has a NSInvocation + +267 +00:13:06,820 --> 00:13:09,320 +which is really just a wrapper for a calling a method. + +268 +00:13:09,322 --> 00:13:11,756 +But I'm not gonna show you that, you don't really need to + +269 +00:13:11,758 --> 00:13:14,592 +know it because this one's just as good right here. + +270 +00:13:14,594 --> 00:13:16,194 +This one's target and selector so + +271 +00:13:16,196 --> 00:13:18,263 +this is what we saw on the slides. So here it is. + +272 +00:13:18,265 --> 00:13:23,434 +To make this is a little more easy to see here I'm gonna add + +273 +00:13:23,436 --> 00:13:26,838 +some carat returns here. Okay, so here's our + +274 +00:13:26,840 --> 00:13:28,640 +scheduledTimerWithTimeInter- val. + +275 +00:13:28,642 --> 00:13:32,143 +So, we need a time interval. I'm gonna be a good programmer + +276 +00:13:32,145 --> 00:13:34,846 +here and I'm gonna create a little constant struct here. + +277 +00:13:34,848 --> 00:13:38,550 +I'm gonna call it my BlinkRate and, so + +278 +00:13:38,552 --> 00:13:45,023 +I'll have a static let here which is the ClosedDuration. + +279 +00:13:45,025 --> 00:13:46,191 +Which will have the, I don't know, + +280 +00:13:46,193 --> 00:13:48,793 +you close your eyes for less than half a second. + +281 +00:13:48,795 --> 00:13:51,963 +Something like that. And then we'll have our OpenDuration. + +282 +00:13:51,965 --> 00:13:54,766 +Now this really doesn't wanna be a constant. If you think + +283 +00:13:54,768 --> 00:13:58,336 +about how you blink, you don't blink and then exactly five + +284 +00:13:58,338 --> 00:14:01,573 +seconds later you blink again. Okay might seem like a robot, + +285 +00:14:01,575 --> 00:14:04,509 +unfortunately this is kind of a robot. So this really would + +286 +00:14:04,511 --> 00:14:06,444 +probably would be some sort of function you know, + +287 +00:14:06,446 --> 00:14:09,380 +the kinda I don't know does some statistical distribution + +288 +00:14:09,382 --> 00:14:12,150 +of your blinking, but we're just gonna make it every 2.5 + +289 +00:14:12,152 --> 00:14:14,953 +seconds okay. So we can this guy blinking pretty quick. + +290 +00:14:14,955 --> 00:14:16,721 +All right, so he's gonna keep his eyes open for + +291 +00:14:16,723 --> 00:14:20,592 +2.5 seconds, close them for 0.4. So here eyes are closed, + +292 +00:14:20,594 --> 00:14:23,361 +so we want the interval that we're keeping it closed before + +293 +00:14:23,363 --> 00:14:25,730 +we open it again. So this is going to be our + +294 +00:14:25,732 --> 00:14:30,535 +BlinkRate.ClosedDuration, okay. The target is going to + +295 +00:14:30,537 --> 00:14:33,771 +be our self. Now there's a restriction on this self, + +296 +00:14:33,773 --> 00:14:36,074 +the same restriction we had with the other. + +297 +00:14:36,076 --> 00:14:39,310 +A pound sign selector type of APIs, + +298 +00:14:39,312 --> 00:14:42,080 +which is that this class that's receiving this has to + +299 +00:14:42,082 --> 00:14:46,317 +be available to the Objective C run time, okay? And + +300 +00:14:46,319 --> 00:14:49,921 +so that means it essentially has to inherit from MS Object. + +301 +00:14:49,923 --> 00:14:52,857 +Now luckily, self, no problem because we inherit from + +302 +00:14:52,859 --> 00:14:56,461 +faceViewController, which inherits from UIViewController + +303 +00:14:56,463 --> 00:14:59,397 +which inherits eventually from NSObjects. So we're all good + +304 +00:14:59,399 --> 00:15:03,067 +to go here, but just don't get too confused if you try and + +305 +00:15:03,069 --> 00:15:04,402 +do this and it's like it doesn't work. + +306 +00:15:04,404 --> 00:15:07,405 +Because the object you send this message to has to be + +307 +00:15:07,407 --> 00:15:11,309 +Objective C compatible. So the selector we want here, + +308 +00:15:11,311 --> 00:15:13,344 +let's call it, this is the start of the blink, so + +309 +00:15:13,346 --> 00:15:18,016 +I'm gonna call, my selector on the other side end of blink. + +310 +00:15:18,018 --> 00:15:21,853 +So, this is, we're in our BlinkingFaceViewController + +311 +00:15:21,855 --> 00:15:26,624 +here, endBlink I'll call it, the argument on there, okay? + +312 +00:15:27,127 --> 00:15:29,193 +Okay, so, that's what we're gonna, we're gonna call. So, + +313 +00:15:29,195 --> 00:15:34,299 +we're gonna need a method down here, private func endBlink. + +314 +00:15:34,301 --> 00:15:37,769 +It's gonna take that timer as an argument, okay. + +315 +00:15:37,771 --> 00:15:40,738 +But we're gonna end our blink there. UserInfo, that's + +316 +00:15:40,740 --> 00:15:43,141 +a little cookie, I don't really have anything to say. + +317 +00:15:43,143 --> 00:15:45,310 +It's pretty obvious, I open and close my eyes. And + +318 +00:15:45,312 --> 00:15:50,448 +repeat is false. Okay, I can't really have one repeating, + +319 +00:15:50,450 --> 00:15:52,784 +timer, because you don't blink like this. + +320 +00:15:52,786 --> 00:15:54,585 +Eyes closed for one second, eyes open for one second, + +321 +00:15:54,587 --> 00:15:56,587 +eyes closed for one second, you know what I mean, + +322 +00:15:56,589 --> 00:15:57,221 +they're two different timers. + +323 +00:15:57,223 --> 00:15:59,557 +One is the closing one, and one is the opening one. + +324 +00:15:59,559 --> 00:16:03,294 +So I really need Two different timers going back and + +325 +00:16:03,296 --> 00:16:06,564 +forth rather than one just going repeatedly, + +326 +00:16:06,566 --> 00:16:11,135 +okay? Missed that there. Okay, make sense? + +327 +00:16:11,137 --> 00:16:13,104 +Now let's take a look here at this error. + +328 +00:16:13,106 --> 00:16:15,440 +You see the error right here? I put this in here, it's like, + +329 +00:16:15,442 --> 00:16:18,743 +what's the problem here? And it says right here, you have + +330 +00:16:18,745 --> 00:16:22,246 +to add a objc to expose this method to Objective-C. + +331 +00:16:22,248 --> 00:16:25,650 +So I said this had to be an Objective-C compatible method. + +332 +00:16:25,652 --> 00:16:26,351 +Well, what the heck? + +333 +00:16:26,353 --> 00:16:28,653 +Why is it making me put Objective-C there? + +334 +00:16:28,655 --> 00:16:33,057 +And the answer is because I made it private. Okay? + +335 +00:16:33,059 --> 00:16:37,662 +Private methods don't get exposed to Objective-C. So + +336 +00:16:37,664 --> 00:16:38,463 +they inject a C runtime. + +337 +00:16:38,465 --> 00:16:42,200 +As soon as I made that not private, now it worked. + +338 +00:16:42,435 --> 00:16:46,671 +Okay so note that as well. It has to be public method, + +339 +00:16:46,673 --> 00:16:49,140 +okay, or otherwise exposed to objective C. Which you can + +340 +00:16:49,142 --> 00:16:53,544 +do with that at sign over J C as well. Okay, so that's good. + +341 +00:16:53,546 --> 00:16:56,614 +Now another interesting thing about this endBlink here is + +342 +00:16:56,616 --> 00:16:58,349 +that I actually don't need this timer. + +343 +00:16:58,351 --> 00:17:00,485 +Because I don't have any user info, + +344 +00:17:00,487 --> 00:17:01,619 +it's not a repeating timer that I + +345 +00:17:01,621 --> 00:17:03,921 +would want to invalidate. Why do I even need that, + +346 +00:17:03,923 --> 00:17:05,456 +I don't even need that thing. Get that outta there. + +347 +00:17:05,458 --> 00:17:09,227 +And if I get that outta there then I don't need this, okay. + +348 +00:17:09,229 --> 00:17:13,264 +And that's allowed as well. Okay, just like we have + +349 +00:17:13,266 --> 00:17:16,134 +target action, or sometimes we pass the cinder along, + +350 +00:17:16,136 --> 00:17:20,405 +same thing with the timer. All right, so that's it. + +351 +00:17:20,407 --> 00:17:21,873 +What are we gonna do in our endBlink? + +352 +00:17:21,875 --> 00:17:25,209 +In our endBlink, what happens when our blinking is ending? + +353 +00:17:25,211 --> 00:17:28,112 +We got our eyes closed. Now, we open them back up again. + +354 +00:17:28,114 --> 00:17:28,846 +So now we're just gonna say, + +355 +00:17:28,848 --> 00:17:33,151 +faceView dot eyesOpen. Equals true. + +356 +00:17:33,153 --> 00:17:36,254 +And now, we want to queue up another blink. + +357 +00:17:36,256 --> 00:17:39,424 +'Cuz we just want to keep on blinking, right? So I'm going + +358 +00:17:39,426 --> 00:17:42,427 +to do that with another timer. So we're going to copy and + +359 +00:17:42,429 --> 00:17:45,163 +paste this right here. This time, though, + +360 +00:17:45,165 --> 00:17:47,999 +it's our open duration. This is how long the ice cream will + +361 +00:17:48,001 --> 00:17:50,601 +be open until we start blinking again. And instead of + +362 +00:17:50,603 --> 00:17:55,907 +endBlink here, now we're start blinking again, okay. Again, + +363 +00:17:55,909 --> 00:18:00,411 +error because this needs to be public, okay, cuz now we're + +364 +00:18:00,413 --> 00:18:03,848 +calling this one, these guys are calling each other, okay. + +365 +00:18:03,850 --> 00:18:08,853 +That good, everyone understand all that? + +366 +00:18:09,722 --> 00:18:13,724 +Okay, so let's see if that works for us. + +367 +00:18:17,397 --> 00:18:20,431 +All right, here's our guy right here. And sure enough, + +368 +00:18:20,433 --> 00:18:25,570 +he's blinking, okay? And you know, if we go to other ones, + +369 +00:18:25,572 --> 00:18:30,808 +they'll all blink. Got it? + +370 +00:18:30,810 --> 00:18:33,945 +Okay so that's it for timer. Hopefully that's a simple + +371 +00:18:33,947 --> 00:18:37,215 +example to show you how we use timer. So the eye blinking is + +372 +00:18:37,217 --> 00:18:40,118 +not really, we wouldn't really necessarily animation but + +373 +00:18:40,120 --> 00:18:42,553 +it's kind of involved in the animation, + +374 +00:18:42,555 --> 00:18:45,790 +right? And the next demo I show you we're going to + +375 +00:18:45,792 --> 00:18:47,758 +actually animate the opening and closing the eyes. + +376 +00:18:47,760 --> 00:18:50,027 +Because right there the eyes are just popping open and + +377 +00:18:50,029 --> 00:18:52,997 +popping shut, popping open. That's not really animating + +378 +00:18:52,999 --> 00:18:59,070 +them okay? So we'll show that in our next demo. All right + +379 +00:18:59,072 --> 00:19:04,609 +back to our slides here. Okay so + +380 +00:19:04,611 --> 00:19:07,979 +let's do a little overview of the kinds of animation that + +381 +00:19:07,981 --> 00:19:10,948 +are available in iOS. Okay this is most of the kinds. + +382 +00:19:10,950 --> 00:19:15,520 +One is there are three UIView properties that you can + +383 +00:19:15,522 --> 00:19:19,390 +animate the changing of okay which is the frame, + +384 +00:19:19,392 --> 00:19:21,926 +the transform which is like that rotation thing and + +385 +00:19:21,928 --> 00:19:23,561 +the alpha which is the transparency so + +386 +00:19:23,563 --> 00:19:26,030 +you can animate those. We'll talk about doing that. + +387 +00:19:26,032 --> 00:19:29,367 +You can also animate view controller transitions. + +388 +00:19:29,369 --> 00:19:31,002 +You noticed that UINavigationController when + +389 +00:19:31,004 --> 00:19:34,705 +you click to another one it slides into another it kinda, + +390 +00:19:34,707 --> 00:19:38,876 +it animated, like cards sliding in, right? Or + +391 +00:19:38,878 --> 00:19:42,180 +sliding off. So this whole mechanism for building your + +392 +00:19:42,182 --> 00:19:46,017 +own UI navigation controller like things, right, + +393 +00:19:46,019 --> 00:19:50,888 +that have little sub UI view controllers that move in and + +394 +00:19:50,890 --> 00:19:52,657 +out, and we're not going to talk about that at all, + +395 +00:19:52,659 --> 00:19:54,358 +because you're not going to be doing that in this class, + +396 +00:19:54,360 --> 00:19:57,361 +it's a little bit of advanced design, but when you go out in + +397 +00:19:57,363 --> 00:19:58,930 +the real world, you might figure out some way, + +398 +00:19:58,932 --> 00:20:01,832 +you know. I know the Facebook app has a little tray that + +399 +00:20:01,834 --> 00:20:05,269 +slides out from the left. OK? It's something they designed + +400 +00:20:05,271 --> 00:20:07,004 +and it's kinda like U I navigation control, but + +401 +00:20:07,006 --> 00:20:10,107 +it only slides out part way. Okay? So I'm sure they had to + +402 +00:20:10,109 --> 00:20:14,345 +use this mechanism to make that animation happen. + +403 +00:20:14,347 --> 00:20:17,949 +Core animation is a non object oriented, + +404 +00:20:17,951 --> 00:20:21,552 +API that underlies almost all the animation we're gonna talk + +405 +00:20:21,554 --> 00:20:24,589 +about here. Okay? It's the big beat engine + +406 +00:20:24,591 --> 00:20:28,125 +that's gong on underneath all this, it's making it all work. + +407 +00:20:28,127 --> 00:20:29,760 +Unfortunately I don't have time to talk about it, + +408 +00:20:29,762 --> 00:20:31,596 +we're gonna talk about the higher level things that + +409 +00:20:31,598 --> 00:20:33,664 +are build on top of core animation But + +410 +00:20:33,666 --> 00:20:36,334 +you should know it's there. And then a lot of people do + +411 +00:20:36,336 --> 00:20:39,637 +do Core Animation stuff in their final projects. Okay? + +412 +00:20:39,639 --> 00:20:41,439 +It's a good not-covered-in-lecture thing, + +413 +00:20:41,441 --> 00:20:43,608 +and there's things you can do in Core Animation that you + +414 +00:20:43,610 --> 00:20:47,745 +can't do with UIView level animation. Okay? There's + +415 +00:20:47,747 --> 00:20:51,749 +a window from your UIView into the Core Animation world, + +416 +00:20:51,751 --> 00:20:54,752 +which is the layer. If you look and there's a CA layer, + +417 +00:20:54,754 --> 00:20:58,422 +Core Animation layer, that's what CA layer stands for And + +418 +00:20:58,424 --> 00:20:59,090 +there's a property in view for + +419 +00:20:59,092 --> 00:21:01,659 +that, and that's how you can kind of get down to the core + +420 +00:21:01,661 --> 00:21:04,228 +animation layer and start doing core animation things. + +421 +00:21:04,230 --> 00:21:07,064 +Like core animation can do rounded recs on the edges + +422 +00:21:07,066 --> 00:21:09,133 +of your views and things like that. Masks, + +423 +00:21:09,135 --> 00:21:14,071 +all kinds of fun stuff. Okay? If you want to do 3-D, + +424 +00:21:14,073 --> 00:21:17,275 +there's OpenGL. OpenGL is bundled with IOS, so, + +425 +00:21:17,277 --> 00:21:20,378 +how many people here have experience with OpenGL or + +426 +00:21:20,380 --> 00:21:23,014 +doing 3-D? Okay, so a few of you. So you can do that, + +427 +00:21:23,016 --> 00:21:26,717 +full OpenGL support in IOS. There's also something called + +428 +00:21:26,719 --> 00:21:30,554 +SpriteKit, which is like 2.5D. Okay, this is how, + +429 +00:21:30,556 --> 00:21:34,525 +when you make an animated thing out of images that kind + +430 +00:21:34,527 --> 00:21:37,495 +of are overlapping each other and moving around, right? + +431 +00:21:37,497 --> 00:21:40,097 +Some guy walking though a castle and you know, + +432 +00:21:40,099 --> 00:21:42,233 +you find some monster, and he's fighting against it. + +433 +00:21:42,235 --> 00:21:45,536 +And it's not really being drawn in 3D like OpenGL. + +434 +00:21:45,538 --> 00:21:47,505 +It's being drawn with images overlapping, but + +435 +00:21:47,507 --> 00:21:50,007 +they're kind of 3D looking images. And so, + +436 +00:21:50,009 --> 00:21:53,611 +SpriteKit manages not just the overlapping images and + +437 +00:21:53,613 --> 00:21:56,080 +how they all move around each other. But, + +438 +00:21:56,082 --> 00:21:57,615 +it also can do particles, so + +439 +00:21:57,617 --> 00:22:00,017 +you can do things like explosions and fire and + +440 +00:22:00,019 --> 00:22:01,952 +all kinds of things. So, it's a really great thing for + +441 +00:22:01,954 --> 00:22:06,624 +building You know these two and a half D like animated + +442 +00:22:06,626 --> 00:22:09,293 +things, we're not gonna talk anything about that in this + +443 +00:22:09,295 --> 00:22:12,263 +class sorry about it, there's gotta be limits and there's + +444 +00:22:12,265 --> 00:22:18,102 +one of them. There's also for views dynamic animation and + +445 +00:22:18,104 --> 00:22:20,838 +this is essentially animating using physics so + +446 +00:22:20,840 --> 00:22:23,441 +you assign gravity and collision boundaries and + +447 +00:22:23,443 --> 00:22:27,511 +things like that to views, and then you just say go, and + +448 +00:22:27,513 --> 00:22:30,748 +gravity starts pulling on it, and it hits the boundary and + +449 +00:22:30,750 --> 00:22:33,084 +it bounces off and things like that, okay? + +450 +00:22:33,086 --> 00:22:37,588 +So it's physics-based animation of views. + +451 +00:22:37,590 --> 00:22:38,823 +That I am going to talk about again. + +452 +00:22:38,825 --> 00:22:40,691 +I won't have time to get all the way through that, but + +453 +00:22:40,693 --> 00:22:43,527 +I have a big demo on that in the next lecture. But + +454 +00:22:43,529 --> 00:22:46,564 +today I'm going to focus on the UI View animation. + +455 +00:22:46,566 --> 00:22:50,534 +The first one is this simple one where you can change + +456 +00:22:50,536 --> 00:22:53,037 +any of these three properties; frame, transform or + +457 +00:22:53,039 --> 00:22:58,042 +alpha. These are the primary ones you can change. + +458 +00:22:58,044 --> 00:23:00,678 +It will animate the change, the from and + +459 +00:23:00,680 --> 00:23:04,348 +the to, of the values of these three properties. So, + +460 +00:23:04,350 --> 00:23:06,984 +it's done with UIView class methods. + +461 +00:23:06,986 --> 00:23:11,255 +So you say, UIView, dot, animate duration, okay? + +462 +00:23:11,257 --> 00:23:14,625 +And, inside there, you're going to provide a block. + +463 +00:23:14,627 --> 00:23:15,092 +And inside that block, + +464 +00:23:15,094 --> 00:23:18,729 +you're gonna change one of these three things. Okay? And + +465 +00:23:18,731 --> 00:23:21,065 +it's going to animate that change over + +466 +00:23:21,067 --> 00:23:24,368 +time. Okay? And it animates in a very configurable + +467 +00:23:24,370 --> 00:23:27,304 +way, as you will see. What's interesting, though, is, even + +468 +00:23:27,306 --> 00:23:29,807 +though you're going to give a block to these methods and + +469 +00:23:29,809 --> 00:23:31,375 +it's going to animate these changes, + +470 +00:23:31,377 --> 00:23:34,912 +it's going to execute that block you give it immediately. + +471 +00:23:34,914 --> 00:23:37,548 +So these values are going to change instantly to the end + +472 +00:23:37,550 --> 00:23:40,284 +point of your animation. So even while the animation is + +473 +00:23:40,286 --> 00:23:41,919 +happening on screen, they're already changed. + +474 +00:23:41,921 --> 00:23:44,388 +Okay, that's something really important to understand + +475 +00:23:44,390 --> 00:23:47,158 +about how animation works in general, even core animation. + +476 +00:23:47,160 --> 00:23:48,793 +When you change things, they change immediately. + +477 +00:23:48,795 --> 00:23:52,296 +It's, on screen is really just taking your time to show + +478 +00:23:52,298 --> 00:23:54,532 +the user what the world looks like okay. + +479 +00:23:54,534 --> 00:23:57,201 +You're not actually, the animation doesn't change + +480 +00:23:57,203 --> 00:24:00,404 +the things over time, it only shows the change over time. + +481 +00:24:00,406 --> 00:24:02,306 +Okay, important thing to understand there. So + +482 +00:24:02,308 --> 00:24:04,975 +here's the method, or one of the methods, kind of the one + +483 +00:24:04,977 --> 00:24:07,878 +with the most arguments here, animate with duration right, + +484 +00:24:07,880 --> 00:24:12,183 +class function on UI view. You can see here that it has + +485 +00:24:12,185 --> 00:24:14,718 +a time interval for how long this animation's gonna take. + +486 +00:24:14,720 --> 00:24:17,288 +You know, is it gonna take two seconds, half a second, or + +487 +00:24:17,290 --> 00:24:22,293 +whatever? Also, you can delay the start of the animation, + +488 +00:24:22,295 --> 00:24:24,528 +like start this animation two seconds from now. + +489 +00:24:24,530 --> 00:24:27,198 +Why would you ever wanna delay that? Because maybe you're + +490 +00:24:27,200 --> 00:24:29,633 +gonna have some animation going on during that two + +491 +00:24:29,635 --> 00:24:33,037 +seconds, okay? So you might have three or four animations + +492 +00:24:33,039 --> 00:24:35,739 +that you queue up, one of them to start in two seconds, + +493 +00:24:35,741 --> 00:24:37,475 +one starts right now. It takes two seconds, + +494 +00:24:37,477 --> 00:24:39,877 +whatever. You can do that, so that's why you might + +495 +00:24:39,879 --> 00:24:43,047 +wanna delay the start of it, then options we'll talk about + +496 +00:24:43,049 --> 00:24:45,282 +later. Here's that block I'm talking about, + +497 +00:24:45,284 --> 00:24:48,886 +animations this first green one here, takes no arguments, + +498 +00:24:48,888 --> 00:24:49,587 +returns no arguments. + +499 +00:24:49,589 --> 00:24:52,289 +You can put anything in you want in there that changes + +500 +00:24:52,291 --> 00:24:56,060 +the frame, the transform, and the alpha, okay? + +501 +00:24:56,062 --> 00:25:00,130 +And then completion is another block, it has an argument to + +502 +00:25:00,132 --> 00:25:02,633 +the block which is boolean, whether it finished + +503 +00:25:02,635 --> 00:25:06,704 +this animation, you asked it to change to some end point, + +504 +00:25:06,706 --> 00:25:09,607 +if it got there with the animation, then this will be + +505 +00:25:09,609 --> 00:25:12,510 +called with this true. If it got interrupted somehow, and + +506 +00:25:12,512 --> 00:25:13,644 +I'll talk about how that can happen, + +507 +00:25:13,646 --> 00:25:16,447 +then this will get called with this finish being false. + +508 +00:25:16,449 --> 00:25:19,683 +In other words, I wasn't able to complete the animation + +509 +00:25:19,685 --> 00:25:22,720 +of those things you changed. All right, so + +510 +00:25:22,722 --> 00:25:25,689 +here's an example of calling this. Let's say I have a view, + +511 +00:25:25,691 --> 00:25:28,392 +my view, and it has an alpha of 1, in other words it's + +512 +00:25:28,394 --> 00:25:31,595 +fully opaque. And if I get to this piece of code, and + +513 +00:25:31,597 --> 00:25:35,032 +I find that my view is fully opaque, I'm going to make it + +514 +00:25:35,034 --> 00:25:37,935 +fully transparent and then remove it from the super, + +515 +00:25:37,937 --> 00:25:40,638 +from the view hierarchy, remove it from the super view. + +516 +00:25:40,640 --> 00:25:42,473 +Okay, take it right out of there. Okay, + +517 +00:25:42,475 --> 00:25:45,409 +that's what I'm gonna do. So, I'm not gonna, + +518 +00:25:45,411 --> 00:25:48,479 +it's gonna take three seconds for it to fade away. Okay, + +519 +00:25:48,481 --> 00:25:51,315 +I'm gonna be animating Alpha here, but I'm not gonna start + +520 +00:25:51,317 --> 00:25:53,817 +for another two seconds. I don't know why. Okay, and + +521 +00:25:53,819 --> 00:25:55,619 +again, maybe I'm making the view spin around for + +522 +00:25:55,621 --> 00:25:59,089 +a couple seconds before it animates out, I don't know. + +523 +00:25:59,091 --> 00:26:02,026 +Here are some options, for example, here the option I'm + +524 +00:26:02,028 --> 00:26:05,262 +using is curve linear, that means the fade out is going + +525 +00:26:05,264 --> 00:26:07,998 +to happen linearly, okay, it's going to fade + +526 +00:26:08,000 --> 00:26:09,633 +out from 1.0 down to zero, + +527 +00:26:09,635 --> 00:26:12,803 +which is where we're going linearly, evenly. + +528 +00:26:12,805 --> 00:26:15,539 +Okay? Smoothly. There are other curves that you can do, + +529 +00:26:15,541 --> 00:26:19,910 +and I'll talk about that in a second. Here's my block. + +530 +00:26:19,912 --> 00:26:22,212 +In my block, I just set my alpha to 0. + +531 +00:26:22,214 --> 00:26:25,649 +That's where I want it to be eventually, okay? So + +532 +00:26:25,651 --> 00:26:27,851 +I set it to 0. Now again, when I call this, + +533 +00:26:27,853 --> 00:26:31,589 +it immediately sets alpha to 0. Alpha's not going to be set + +534 +00:26:31,591 --> 00:26:33,924 +to 0 in five seconds, it's going to be set to 0 now. + +535 +00:26:33,926 --> 00:26:36,694 +It's just going to appear on screen in five seconds. + +536 +00:26:36,696 --> 00:26:39,897 +And in the completion here, I'm saying 'if $0', which + +537 +00:26:39,899 --> 00:26:43,267 +means if it finished, then remove it from the super view. + +538 +00:26:43,269 --> 00:26:45,869 +So if this animation of the alpha got interrupted, + +539 +00:26:45,871 --> 00:26:48,872 +by some other animation, then I'm not going to remove myself + +540 +00:26:48,874 --> 00:26:50,341 +from the super view, I'm only going to do it if + +541 +00:26:50,343 --> 00:26:54,979 +I make it all the way down to zero. This block, is going + +542 +00:26:54,981 --> 00:26:58,115 +to be executed five seconds from now, or whenever this + +543 +00:26:58,117 --> 00:27:00,584 +animation gets interrupted, if before then. Okay, so + +544 +00:27:00,586 --> 00:27:05,289 +this block is going to be executed later. Notice that + +545 +00:27:05,291 --> 00:27:09,026 +I put 'print("myView.alpha =\(myView.alpha)"' there. + +546 +00:27:09,028 --> 00:27:12,262 +This is going to print 'myView.alpha = 0' because + +547 +00:27:12,264 --> 00:27:15,232 +this 'animateWithDuration' executes this block and + +548 +00:27:15,234 --> 00:27:18,202 +returns immediately. So, myView.alpha is gonna be 0. + +549 +00:27:18,204 --> 00:27:22,973 +Okay? And it's gonna stay 0 all the way through this + +550 +00:27:22,975 --> 00:27:25,275 +five seconds that it takes for this animation to happen + +551 +00:27:25,277 --> 00:27:27,277 +because this animation really has nothing to do, + +552 +00:27:27,279 --> 00:27:30,981 +has no effect on the setting of alpha. It just, + +553 +00:27:30,983 --> 00:27:35,152 +is how we're presenting this change to the user. Okay + +554 +00:27:35,154 --> 00:27:37,287 +let's talk about some of those options. There are tons and + +555 +00:27:37,289 --> 00:27:39,623 +tons of options. I'm not gonna go over all of them for + +556 +00:27:39,625 --> 00:27:43,293 +time reasons here, but you saw a CurveLinear there. + +557 +00:27:43,295 --> 00:27:46,597 +Some other curves like CurveEaseinEaseout, + +558 +00:27:46,599 --> 00:27:49,333 +that means it start off animating it slowly, and + +559 +00:27:49,335 --> 00:27:51,769 +then picks up to a normal speed, and then slows down + +560 +00:27:51,771 --> 00:27:55,039 +again at the end. That's an, curve that we usually use for + +561 +00:27:55,041 --> 00:27:57,574 +moving things. Okay? If you have a view on screen and + +562 +00:27:57,576 --> 00:27:59,576 +you want to move it, so you're changing its frame, + +563 +00:27:59,578 --> 00:28:02,112 +you're animating its frame, you don't really want to go + +564 +00:28:02,114 --> 00:28:05,015 +[SOUND], okay? You kinda want it to pick up speed, move, + +565 +00:28:05,017 --> 00:28:07,351 +and then slow down at the end. Okay? + +566 +00:28:07,353 --> 00:28:10,721 +It's just less abrupt, turns out, to do it that way. + +567 +00:28:10,723 --> 00:28:13,357 +So you can specify that. Things like begin from current + +568 +00:28:13,359 --> 00:28:16,393 +state that's an interesting one. If you have an animation + +569 +00:28:16,395 --> 00:28:18,862 +in motion let's say our animation before, let's say + +570 +00:28:18,864 --> 00:28:21,932 +we're half way through showing the alpha going to zeros so + +571 +00:28:21,934 --> 00:28:24,668 +it's half transparent. And then some other animations + +572 +00:28:24,670 --> 00:28:27,805 +comes along and wants to animate it going to full or + +573 +00:28:27,807 --> 00:28:31,308 +peak. Okay, if the other animation said begin from + +574 +00:28:31,310 --> 00:28:34,945 +current state, then when it starts, it would start at 0.5, + +575 +00:28:34,947 --> 00:28:39,083 +alpha of 0.5. Okay, in other words it would grab onto + +576 +00:28:39,085 --> 00:28:41,685 +the alpha of whatever animations and process. + +577 +00:28:41,687 --> 00:28:44,888 +You can think of this as begin from current state means + +578 +00:28:44,890 --> 00:28:49,760 +use the values of these in the animation world, + +579 +00:28:49,762 --> 00:28:51,428 +not in the real world, because in the real world, + +580 +00:28:51,430 --> 00:28:55,099 +the alpha is zero. It was zero as soon as I set it to zero. + +581 +00:28:55,101 --> 00:28:56,567 +So, if you don't have BeginFromCurrentState, + +582 +00:28:56,569 --> 00:28:59,203 +then this new one is gonna use the real world one, and + +583 +00:28:59,205 --> 00:29:01,505 +it's gonna be going to half transparent, + +584 +00:29:01,507 --> 00:29:04,041 +back to zero, up to one, okay? + +585 +00:29:04,043 --> 00:29:06,143 +Because if you don't put that BeginFromCurrentState, + +586 +00:29:06,145 --> 00:29:09,480 +it pays no attention to what's going on in the animation + +587 +00:29:09,482 --> 00:29:11,648 +alone. AllowsUserInteraction, exactly what you think. + +588 +00:29:11,650 --> 00:29:13,484 +You need to put gesture, you've got some view flying + +589 +00:29:13,486 --> 00:29:16,587 +across the screen, can you touch on it while it's moving? + +590 +00:29:16,589 --> 00:29:18,589 +That kind of stuff, you know auto reversing, + +591 +00:29:18,591 --> 00:29:21,125 +does the animation repeat all these things you can go look + +592 +00:29:21,127 --> 00:29:25,129 +this up in the documentation of UIView. Okay. + +593 +00:29:25,131 --> 00:29:29,399 +Sometimes you wanna make other changes to views, not frame, + +594 +00:29:29,401 --> 00:29:33,937 +transform, or Alpha, okay? And you wanna animate the entire + +595 +00:29:33,939 --> 00:29:39,576 +change in there In, at once with some kind of cool looking + +596 +00:29:39,578 --> 00:29:42,546 +thing on screen. For example, dissolve you'd want + +597 +00:29:42,548 --> 00:29:46,150 +to change to dissolve in from the old what it looked like + +598 +00:29:46,152 --> 00:29:48,185 +before to what it's going to look like have it dissolve + +599 +00:29:48,187 --> 00:29:50,687 +over time. Or have it flip over, like I'm gonna use + +600 +00:29:50,689 --> 00:29:53,524 +an example of a playing card. If you have a playing card and + +601 +00:29:53,526 --> 00:29:54,925 +you change it from face down to face up, + +602 +00:29:54,927 --> 00:29:58,629 +you'd like it to flip. Okay you don't want to just [NOISE] + +603 +00:29:58,631 --> 00:30:00,197 +change to face up, that's very abrupt. + +604 +00:30:00,199 --> 00:30:02,800 +You want it to kind of flip over. Okay. And there's even + +605 +00:30:02,802 --> 00:30:05,235 +a curl up if you have a view that fills the whole screen, + +606 +00:30:05,237 --> 00:30:07,638 +it can curl up from the bottom like it's a piece of + +607 +00:30:07,640 --> 00:30:08,572 +paper that someone is looking under. + +608 +00:30:08,574 --> 00:30:12,176 +Okay you've probably seen that sometimes. You do this with + +609 +00:30:12,178 --> 00:30:16,480 +another U-I view class method called transition with a view. + +610 +00:30:16,482 --> 00:30:21,485 +Kay, you specify the view like a playing card view or + +611 +00:30:21,487 --> 00:30:27,224 +whatever, so this is the view that's changing, + +612 +00:30:27,226 --> 00:30:30,160 +and this is duration of the animation just like we + +613 +00:30:30,162 --> 00:30:31,128 +have the duration of the previous one, + +614 +00:30:31,130 --> 00:30:33,197 +how long it's gonna take the card to flip over or + +615 +00:30:33,199 --> 00:30:36,934 +whatever. More options the same options as before. + +616 +00:30:36,936 --> 00:30:40,437 +Here's the closure okay? This closure this green closure + +617 +00:30:40,439 --> 00:30:43,974 +here it can change anything at once about the view okay? + +618 +00:30:43,976 --> 00:30:46,476 +Because it doesn't have to be restricted to those three that + +619 +00:30:46,478 --> 00:30:48,478 +we know because it's not gonna actually animate any + +620 +00:30:48,480 --> 00:30:51,348 +in between states. It's just gonna take the end state and + +621 +00:30:51,350 --> 00:30:53,784 +the beginning state and flip between the two or + +622 +00:30:53,786 --> 00:30:56,320 +cross dissolve between the two. You see what I mean? + +623 +00:30:56,322 --> 00:30:58,255 +It's not going to show intermediate positions of + +624 +00:30:58,257 --> 00:31:01,558 +the frame moving around or anything like that, okay? Umm, + +625 +00:31:01,560 --> 00:31:05,128 +so this contains anything you want and it also gets executed + +626 +00:31:05,130 --> 00:31:09,066 +immediately, okay, even though the animation will take time + +627 +00:31:09,068 --> 00:31:11,368 +to show the flip, the change gets made immediately. + +628 +00:31:11,370 --> 00:31:13,904 +And then here's completion, the same completion thing that + +629 +00:31:13,906 --> 00:31:15,906 +will let you know whether it finished. This one is almost + +630 +00:31:15,908 --> 00:31:19,009 +always going to finish here, it's hard to interrupt. And + +631 +00:31:19,011 --> 00:31:22,312 +one like this. All right, so here's the playing card + +632 +00:31:22,314 --> 00:31:24,648 +example. I've got my playing card view up here. + +633 +00:31:24,650 --> 00:31:26,950 +I'm gonna take a little less than a second. + +634 +00:31:26,952 --> 00:31:29,786 +I'm using the transition flip from left option. + +635 +00:31:29,788 --> 00:31:32,489 +So, it's gonna flip my card over from the left edge being + +636 +00:31:32,491 --> 00:31:36,326 +lifted up and over. All I'm doing in my block is changing + +637 +00:31:36,328 --> 00:31:39,363 +some attribute of my playing card view. Card is face up + +638 +00:31:39,365 --> 00:31:42,566 +to card is not face up, so I'm toggling card is face up, + +639 +00:31:42,568 --> 00:31:45,702 +now when I do this that's going to change the whole look + +640 +00:31:45,704 --> 00:31:48,739 +of my playing card view from the back of the card to one + +641 +00:31:48,741 --> 00:31:52,175 +of the front, you know, cards face up. So essentially, + +642 +00:31:52,177 --> 00:31:54,578 +the system's gonna take a snapshot of what it looked + +643 +00:31:54,580 --> 00:31:57,614 +like before, take a snapshot of what it looked like after. + +644 +00:31:57,616 --> 00:32:00,517 +And then do a flip animation to show the new thing. + +645 +00:32:00,519 --> 00:32:04,788 +Or cross dissolve or whatever options teaches, + +646 +00:32:04,790 --> 00:32:07,758 +okay. So that's that. + +647 +00:32:08,327 --> 00:32:11,595 +Now if you're animating a change to the view hierarchy, + +648 +00:32:11,597 --> 00:32:13,230 +which is to say you've got a view in there and + +649 +00:32:13,232 --> 00:32:14,932 +you're going to remove it from consumer view and + +650 +00:32:14,934 --> 00:32:17,868 +replace it with another view, okay? You've got a view that + +651 +00:32:17,870 --> 00:32:21,338 +you're gonna hide and unhide some other view in its place. + +652 +00:32:21,340 --> 00:32:22,506 +Then you're going to want to use this one, + +653 +00:32:22,508 --> 00:32:26,410 +transitionFromView(toView So, the fromView is the view + +654 +00:32:26,412 --> 00:32:30,213 +that's in the view hierarchy, that's going to leave or be + +655 +00:32:30,215 --> 00:32:33,617 +hidden. And the toView is the one that is going to appear. + +656 +00:32:33,619 --> 00:32:36,586 +All right? And here's the time, and here's the options. + +657 +00:32:36,588 --> 00:32:38,889 +And here's the completion. Okay? Now if you use + +658 +00:32:38,891 --> 00:32:40,991 +the option Show Hide Transition Views, + +659 +00:32:40,993 --> 00:32:43,327 +then instead of removing it from view hierarchy and + +660 +00:32:43,329 --> 00:32:44,962 +adding the other one at the same place, + +661 +00:32:44,964 --> 00:32:46,863 +it'll actually just set dot hidden. Right? + +662 +00:32:46,865 --> 00:32:50,400 +Remember the dot hidden of our on a view, which makes it just + +663 +00:32:50,402 --> 00:32:52,002 +not appear. It's still in the view hierarchy, but + +664 +00:32:52,004 --> 00:32:55,772 +doesn't appear. This will set the .hidden of one, clear + +665 +00:32:55,774 --> 00:32:58,475 +the .hidden of one and, set the .hidden of one to true and + +666 +00:32:58,477 --> 00:33:04,114 +tip the other one to false so that it appears. Okay. So, + +667 +00:33:04,116 --> 00:33:05,582 +that's basically View Animation. + +668 +00:33:05,584 --> 00:33:07,317 +So let me show you a demo of that. + +669 +00:33:07,319 --> 00:33:08,585 +And the demo we're going to do, + +670 +00:33:08,587 --> 00:33:09,453 +two parts here in Face View. + +671 +00:33:09,455 --> 00:33:13,123 +One, we're gonna make our blinking actually, be smooth. + +672 +00:33:13,125 --> 00:33:14,958 +And to do that we're gonna use the flip. But + +673 +00:33:14,960 --> 00:33:17,527 +instead of flip from left, I'm gonna do flip from top. + +674 +00:33:17,529 --> 00:33:19,429 +As you can imagine, if you had the eye open and + +675 +00:33:19,431 --> 00:33:22,099 +you flipped from top, it would, you know, + +676 +00:33:22,101 --> 00:33:24,968 +more smoothly look like it's blinking. And + +677 +00:33:24,970 --> 00:33:27,571 +then for the head shake, so I'm gonna have + +678 +00:33:27,573 --> 00:33:30,273 +this face. It's only 2D, so to shake its head it has to turn + +679 +00:33:30,275 --> 00:33:34,044 +its head sideways like this. It's gonna shake its head, + +680 +00:33:34,046 --> 00:33:34,244 +and to do that, + +681 +00:33:34,246 --> 00:33:36,880 +I'm going to use the things where I change the transform, + +682 +00:33:36,882 --> 00:33:38,849 +which is the rotation of that view. Right, + +683 +00:33:38,851 --> 00:33:41,518 +remember transform is scale, rotation, and translation. + +684 +00:33:41,520 --> 00:33:43,620 +So I'm going to change that to make it shake its head, + +685 +00:33:43,622 --> 00:33:46,556 +basically. Okay, now that's an interesting one because + +686 +00:33:46,558 --> 00:33:49,159 +there's actually multiple moves there, and we're going + +687 +00:33:49,161 --> 00:33:53,096 +to have to chain them together to make it shakes its head. + +688 +00:33:53,332 --> 00:33:58,135 +All right, so let's go back over to A face view, + +689 +00:33:58,137 --> 00:34:01,004 +same place we were there. Now, + +690 +00:34:01,006 --> 00:34:05,675 +to make face view eyes blink, all right, right here. + +691 +00:34:05,677 --> 00:34:11,281 +These eyes need to be views. Okay, because I'm going to use + +692 +00:34:11,283 --> 00:34:14,985 +view animation. So if I want them to flip, okay, they're + +693 +00:34:14,987 --> 00:34:18,221 +going to have to be views. So I have to change my code. It + +694 +00:34:18,223 --> 00:34:22,325 +will turn these eyes into sub views of my face view. Now, + +695 +00:34:22,327 --> 00:34:25,395 +it's really not gonna change the face view that much, okay. + +696 +00:34:25,397 --> 00:34:27,564 +Let's see what it's really like to do that. So + +697 +00:34:27,566 --> 00:34:30,934 +to save a little bit of time, I create an a Eyeview which + +698 +00:34:30,936 --> 00:34:33,070 +we're gonna look at don't worry, okay. So + +699 +00:34:33,072 --> 00:34:34,504 +this is Eyeview. It's just going to be + +700 +00:34:34,506 --> 00:34:38,775 +a view that represents one of these eyes, okay. So, + +701 +00:34:38,777 --> 00:34:42,546 +let's take a look at the eye view. Here it is right here. + +702 +00:34:42,548 --> 00:34:44,781 +The eye view, this code in eye view is + +703 +00:34:44,783 --> 00:34:47,717 +identical to the code I used to have in face view, or still + +704 +00:34:47,719 --> 00:34:49,719 +have in face view which we're going to have to get rid of, + +705 +00:34:49,721 --> 00:34:52,022 +which is this path for eye. Remember path for + +706 +00:34:52,024 --> 00:34:55,092 +eye? We got either a circle, or it was a line, depending + +707 +00:34:55,094 --> 00:34:57,694 +on whether it was open or closed. If you look at this + +708 +00:34:57,696 --> 00:35:01,264 +code here path for eye, it looks just like this. + +709 +00:35:01,266 --> 00:35:04,101 +Okay, now I had to bring over line with color and + +710 +00:35:04,103 --> 00:35:07,671 +eyes open as VARs in my eye view, which I'll have to set + +711 +00:35:07,673 --> 00:35:10,006 +those from here in my face view. Okay, so + +712 +00:35:10,008 --> 00:35:12,609 +I don't need this path for eye anymore, because I'm going to + +713 +00:35:12,611 --> 00:35:16,880 +use subviews to draw my eyes. This is also good, another + +714 +00:35:16,882 --> 00:35:20,717 +way to show you using subviews of other views in code and + +715 +00:35:20,719 --> 00:35:23,320 +how we do that. All right, so I don't need path for i, + +716 +00:35:23,322 --> 00:35:27,057 +I also don't need to do path for i stroke over here. + +717 +00:35:27,059 --> 00:35:30,227 +Because I'm not drawing my i's in my drawRect anymore, + +718 +00:35:30,229 --> 00:35:34,631 +I'm letting a sub-view of mine draw them. Okay? All right, so + +719 +00:35:34,633 --> 00:35:38,235 +how we gonna do this, thing here? So I have a little, + +720 +00:35:38,237 --> 00:35:41,471 +again a little code here. That will, this little piece of + +721 +00:35:41,473 --> 00:35:44,341 +code right here okay this is how we're gonna do this. One, + +722 +00:35:44,343 --> 00:35:47,377 +I'm creating a couple of vars one for the left eye one for + +723 +00:35:47,379 --> 00:35:52,015 +the right eye. It's an EyeView right EyeView is just a UIView + +724 +00:35:52,017 --> 00:35:55,519 +okay that draws those eyes. So it's an EyeView, and + +725 +00:35:55,521 --> 00:35:58,889 +I'm creating it by calling this method create eye + +726 +00:35:58,891 --> 00:36:02,159 +on myself. Now, I'm gonna take a time out + +727 +00:36:02,161 --> 00:36:04,361 +here to talk about these lazys right here. + +728 +00:36:04,363 --> 00:36:07,831 +If I take these lazys out, this will generate an error. + +729 +00:36:07,833 --> 00:36:11,801 +Can anyone tell me why that's an error right there? + +730 +00:36:13,639 --> 00:36:17,841 +Nobody knows? What? >> [INAUDIBLE] + +731 +00:36:17,843 --> 00:36:18,742 +>> Yes. Exactly. + +732 +00:36:18,744 --> 00:36:22,012 +We're in initialization right here. We're initializing these + +733 +00:36:22,014 --> 00:36:25,749 +during initialization, self is not fully initialized. + +734 +00:36:25,751 --> 00:36:29,452 +We can't send it any methods. We can't send create eye to + +735 +00:36:29,454 --> 00:36:32,889 +self right here in the middle of initialization. Okay? + +736 +00:36:32,891 --> 00:36:34,958 +This is part of this class being initialized. + +737 +00:36:34,960 --> 00:36:36,526 +Until the class is fully initialized, + +738 +00:36:36,528 --> 00:36:39,362 +we can't call our own method. That's why putting, + +739 +00:36:39,364 --> 00:36:42,332 +by the way the error message you get in here + +740 +00:36:42,334 --> 00:36:45,001 +is kinda cryptic. So, kinda what it'd look like. + +741 +00:36:45,003 --> 00:36:47,804 +So if you see something like this, all right? + +742 +00:36:47,806 --> 00:36:50,774 +Then you might get the idea, maybe it's that thing where + +743 +00:36:50,776 --> 00:36:54,377 +I'm trying to call a method on myself while I'm initializing. + +744 +00:36:54,379 --> 00:36:59,015 +So why does putting lazy in here fix it? Because lazy + +745 +00:36:59,017 --> 00:37:04,020 +means that the initialization here doesn't happen until + +746 +00:37:04,022 --> 00:37:08,358 +someone asks for this var. Okay, until someone asks for + +747 +00:37:08,360 --> 00:37:10,260 +the leftEye or asks for the rightEye, + +748 +00:37:10,262 --> 00:37:13,330 +these =self.createEye are not gonna happen, and + +749 +00:37:13,332 --> 00:37:14,497 +no one is allowed to ask for + +750 +00:37:14,499 --> 00:37:20,103 +these vars until this thing is fully initialized. So, + +751 +00:37:20,105 --> 00:37:20,403 +all is well. + +752 +00:37:20,405 --> 00:37:23,573 +Because now we can call this createEye to initialize it. So + +753 +00:37:23,575 --> 00:37:27,711 +you see how lazy gets you out of that little conundrum of, + +754 +00:37:27,713 --> 00:37:30,680 +initializing there? And don't forget also you want to put + +755 +00:37:30,682 --> 00:37:34,651 +self dot right here when you're doing a createEye. + +756 +00:37:34,653 --> 00:37:36,786 +Okay? If you're gonna say this equals, you need to make it + +757 +00:37:36,788 --> 00:37:39,389 +clear in your initialization that you're accessing your + +758 +00:37:39,391 --> 00:37:44,394 +self. This creates each of these two eyes. + +759 +00:37:44,396 --> 00:37:47,264 +What does this create eye look like. Let's just create a new + +760 +00:37:47,266 --> 00:37:49,699 +eye view. I'm just calling the initializer here. + +761 +00:37:49,701 --> 00:37:53,737 +I'm going to set it to be not opaque, because eye view + +762 +00:37:53,739 --> 00:37:56,439 +doesn't draw background or have any background set, so + +763 +00:37:56,441 --> 00:37:57,741 +if there was something behind my eye view, + +764 +00:37:57,743 --> 00:38:00,510 +maybe some eye shadow eyeliner or something, + +765 +00:38:00,512 --> 00:38:04,648 +it would show through. Also, I got to transfer the color and + +766 +00:38:04,650 --> 00:38:06,516 +the line with on to the eye view, and + +767 +00:38:06,518 --> 00:38:09,419 +in fact, I need to do this not only here when I create it, + +768 +00:38:09,421 --> 00:38:12,822 +but I probably want to do up here if someone sets the color + +769 +00:38:12,824 --> 00:38:16,393 +right here. In addition to doing set needs display, + +770 +00:38:16,395 --> 00:38:17,861 +I probably want to set my left + +771 +00:38:17,863 --> 00:38:19,362 +eye's color equal to the color and + +772 +00:38:19,364 --> 00:38:24,768 +I want to set my right eye's Color equal to the color. And + +773 +00:38:24,770 --> 00:38:26,436 +same thing here with line width, + +774 +00:38:26,438 --> 00:38:29,005 +in addition to set needs display left eye dot line + +775 +00:38:29,007 --> 00:38:34,177 +width goes to the line width. And right eye dot line width + +776 +00:38:34,179 --> 00:38:38,548 +goes to the line width, and interestingly, + +777 +00:38:38,550 --> 00:38:42,085 +eyes open. Of course, we also want to pass that along, + +778 +00:38:42,087 --> 00:38:45,021 +but we don't actually need set needs display anymore for + +779 +00:38:45,023 --> 00:38:50,760 +eyes open, do we? Because eyes open is no longer drawn by us. + +780 +00:38:50,762 --> 00:38:53,730 +So if it changed, the eye view is the thing that + +781 +00:38:53,732 --> 00:38:53,763 +here we just need to say lefteye.eyesopen = eyesOpen. + +782 +00:38:53,765 --> 00:38:59,102 +needs to change, so + +783 +00:38:59,104 --> 00:39:02,906 +And rightEye.eyesOpen = eyesOpen, + +784 +00:39:02,908 --> 00:39:08,778 +okay? Since there and don't understand why we don't need + +785 +00:39:08,780 --> 00:39:10,914 +setNeedsDisplay? Because we're not drawing the eyes anymore. + +786 +00:39:10,916 --> 00:39:15,151 +We have a subview that does it for us now. Okay, so + +787 +00:39:15,153 --> 00:39:16,286 +here we've got the eye created. + +788 +00:39:16,288 --> 00:39:18,621 +Now after we've set the color and line width, + +789 +00:39:18,623 --> 00:39:21,991 +then we're just going to add it as a subview of ourselves, + +790 +00:39:21,993 --> 00:39:22,892 +which are great, okay. Now, + +791 +00:39:22,894 --> 00:39:27,530 +a little bit of a problem here, where is this eye? Okay, + +792 +00:39:27,532 --> 00:39:28,932 +we haven't specified where this eye. + +793 +00:39:28,934 --> 00:39:31,735 +We created it with this initializer which doesn't + +794 +00:39:31,737 --> 00:39:35,105 +specify the frame. So, it's like, we don't even know where + +795 +00:39:35,107 --> 00:39:38,041 +this eye is. It's probably at zero, zero and it's also size + +796 +00:39:38,043 --> 00:39:40,677 +zero, zero. So, we obviously need to position and + +797 +00:39:40,679 --> 00:39:44,514 +size each of these two eyes. Okay, to make this work. So + +798 +00:39:44,516 --> 00:39:48,218 +I created this little function right here to position an eye + +799 +00:39:48,220 --> 00:39:51,588 +okay, and it just takes the eye you want to position and + +800 +00:39:51,590 --> 00:39:54,824 +where you want the center of the eye to be. Okay, now it + +801 +00:39:54,826 --> 00:39:57,794 +knows the size the eye is supposed to be because it has + +802 +00:39:57,796 --> 00:39:59,662 +this skull radius to eye radius thing, so + +803 +00:39:59,664 --> 00:40:02,665 +it's setting the size to that. And it creates a rectangle + +804 +00:40:02,667 --> 00:40:06,336 +that's initially in the upper left with the proper size. And + +805 +00:40:06,338 --> 00:40:10,206 +then it sets the eye center to be whatever center you wanted, + +806 +00:40:10,208 --> 00:40:13,309 +okay? So, trivial little piece of code that just positions + +807 +00:40:13,311 --> 00:40:15,945 +the eye. So now the question is, + +808 +00:40:15,947 --> 00:40:19,482 +where do we call this position eye? Okay, + +809 +00:40:19,484 --> 00:40:24,120 +where do we set the position of these eyes. I can't do it + +810 +00:40:24,122 --> 00:40:28,024 +here, this create eye is could be happening any time. + +811 +00:40:28,026 --> 00:40:29,993 +I don't what my bounds are at this point. + +812 +00:40:29,995 --> 00:40:32,395 +Might not even be, my bounds might be zero zero also, so + +813 +00:40:32,397 --> 00:40:35,665 +I don't even know where my eye goes, so that's no good. + +814 +00:40:35,667 --> 00:40:40,437 +There's no view did layout sub views, okay. This is a UI + +815 +00:40:40,439 --> 00:40:44,841 +view, not UI view controller. Okay, so there's no view to, + +816 +00:40:44,843 --> 00:40:47,010 +there's no view controller life cycle. We're in a view, + +817 +00:40:47,012 --> 00:40:49,813 +not a view controller. So, we can't do that. I can't call it + +818 +00:40:49,815 --> 00:40:52,015 +from my controller. Here's my controller. + +819 +00:40:52,017 --> 00:40:55,552 +Because my controller has no idea that faceView is using + +820 +00:40:55,554 --> 00:41:00,190 +a subview to draw its eye. If you go look back in face view, + +821 +00:41:00,192 --> 00:41:03,493 +all this stuff about the eye, it's all private. Private. + +822 +00:41:03,495 --> 00:41:06,162 +Private. It's all private. So there's absolutely no way that + +823 +00:41:06,164 --> 00:41:10,934 +my controller can reach down into me and do that. This + +824 +00:41:10,936 --> 00:41:14,337 +is going to show you how you find out when your view needs + +825 +00:41:14,339 --> 00:41:19,476 +to lay out it's subviews. It's a method called conveniently. + +826 +00:41:19,478 --> 00:41:21,711 +layoutSubviews(). Okay? So, + +827 +00:41:21,713 --> 00:41:25,949 +layoutSubviews() is the method in view that's called whenever + +828 +00:41:25,951 --> 00:41:29,686 +the system wants the view to lay it's subviews out. Okay? + +829 +00:41:29,688 --> 00:41:32,255 +And those two eyes are subviews of ours. So we get to + +830 +00:41:32,257 --> 00:41:36,926 +lay them out. Okay? So, we'll call super.layoutSubviews(). + +831 +00:41:36,928 --> 00:41:37,961 +Always nice to do that, + +832 +00:41:37,963 --> 00:41:38,528 +definitely wanna do that for + +833 +00:41:38,530 --> 00:41:41,564 +that. And then we're gonna position these eyes so + +834 +00:41:41,566 --> 00:41:44,367 +we're just going to call it positionEye with position to + +835 +00:41:44,369 --> 00:41:48,771 +leftEye. Where does the leftEye center belong. + +836 +00:41:48,773 --> 00:41:51,207 +Actually, believe it or not, from our old code, + +837 +00:41:51,209 --> 00:41:54,978 +we have this getEyeCenter method here, okay. So + +838 +00:41:54,980 --> 00:41:57,580 +we'll just use that that tells us the center of the eye. + +839 +00:41:57,582 --> 00:42:01,251 +Awesome. So we'll say GetEyeCenter, + +840 +00:42:01,253 --> 00:42:04,654 +the left eye. Okay? And we'll do the same thing for + +841 +00:42:04,656 --> 00:42:12,428 +the right eye. Okay? There we go. + +842 +00:42:12,430 --> 00:42:14,030 +So be don't confused in the difference between layout + +843 +00:42:14,032 --> 00:42:16,466 +subviews and view did layout subviews, okay? + +844 +00:42:16,468 --> 00:42:18,701 +If you did layout subviews as part of the view controller + +845 +00:42:18,703 --> 00:42:20,537 +life cycle, that's a view controller thing. + +846 +00:42:20,539 --> 00:42:23,573 +Layout subviews is a view method where a view's + +847 +00:42:23,575 --> 00:42:27,377 +being asked to actually lay it's subviews out, okay? Now, + +848 +00:42:27,379 --> 00:42:31,714 +a lot of times your subviews get laid out by auto layout. + +849 +00:42:31,716 --> 00:42:34,150 +Right, in that case you don't need to do anything in layout + +850 +00:42:34,152 --> 00:42:38,121 +subviews. But here these eyes, we can't really put an auto + +851 +00:42:38,123 --> 00:42:40,690 +layout for the eyes, maybe we could I'd have to + +852 +00:42:40,692 --> 00:42:42,425 +think about that actually, it might be possible, + +853 +00:42:42,427 --> 00:42:44,894 +believe it or not, but we're just going to do it in code, + +854 +00:42:44,896 --> 00:42:46,863 +so you can learn how to do it in code as well, and so + +855 +00:42:46,865 --> 00:42:48,798 +when layout subjects happen, we're just always going to be + +856 +00:42:48,800 --> 00:42:51,067 +moving our eyes to the right thing. Layout subjects is + +857 +00:42:51,069 --> 00:42:53,503 +always going to be called if our bounds changed. Because of + +858 +00:42:53,505 --> 00:42:55,838 +our balance change, we clearly need to lay our subviews out. + +859 +00:42:55,840 --> 00:42:59,075 +This ads of view right here is gonna call layout subviews, + +860 +00:42:59,077 --> 00:43:01,010 +because layout subviews to be called. Because anytime you + +861 +00:43:01,012 --> 00:43:07,150 +change your subviews you gotta lay them out again, okay? + +862 +00:43:07,152 --> 00:43:12,221 +All right, so see if anything else we wanna do here. + +863 +00:43:12,223 --> 00:43:15,558 +I think that's pretty much everything. Hopefully + +864 +00:43:15,560 --> 00:43:19,596 +this will work. Let's see if this works. I just want to + +865 +00:43:19,598 --> 00:43:21,397 +make sure I haven't broken anything. Obviously, + +866 +00:43:21,399 --> 00:43:24,067 +we haven't done any animation for the eye blinking here. + +867 +00:43:24,069 --> 00:43:28,905 +But hopefully, we've replaced our view. Or our eyes, rather, + +868 +00:43:28,907 --> 00:43:32,809 +with a view. And it looks like it's working, okay? Got these. + +869 +00:43:32,811 --> 00:43:33,309 +Let's see if we can rotate. Yep, + +870 +00:43:33,311 --> 00:43:37,080 +it's all still working. Okay, so we haven't broken anything. + +871 +00:43:37,082 --> 00:43:41,150 +So now, we want to make these eyes animate closing and + +872 +00:43:41,152 --> 00:43:45,254 +opening, okay, by using that transition flip from top, + +873 +00:43:45,256 --> 00:43:46,756 +okay? So, how are we going to do that? + +874 +00:43:46,758 --> 00:43:48,891 +So I'm going to do all that in the eye view, + +875 +00:43:48,893 --> 00:43:50,460 +I am going to be object oriented here. + +876 +00:43:50,462 --> 00:43:53,796 +The animation of the eye, that's an eye thing so + +877 +00:43:53,798 --> 00:43:54,597 +it should be in the eye view, + +878 +00:43:54,599 --> 00:43:56,199 +that shouldn't be in the face view. Okay, + +879 +00:43:56,201 --> 00:44:00,203 +to be in the EyeView. So we're gonna animate this thing right + +880 +00:44:00,205 --> 00:44:04,941 +here, this eyesOpening, okay. We want to animate eyesOpen. + +881 +00:44:04,943 --> 00:44:06,142 +So, how are we gonna animate eyesOpen? + +882 +00:44:06,144 --> 00:44:10,213 +Well, basically anytime an eyesOpen gets set, okay, + +883 +00:44:10,215 --> 00:44:12,815 +we need to set it in an animated way. So I'd + +884 +00:44:12,817 --> 00:44:15,685 +almost like to put something in didSet, except for + +885 +00:44:15,687 --> 00:44:19,322 +didSet would be too late, because it already got set + +886 +00:44:19,324 --> 00:44:21,591 +Okay, I have to animate the setting of it. + +887 +00:44:21,593 --> 00:44:23,760 +I have to provide a little closure there, right, + +888 +00:44:23,762 --> 00:44:27,063 +to that animate method that does the setting of it. So + +889 +00:44:27,065 --> 00:44:28,431 +it did set a little too late. + +890 +00:44:28,433 --> 00:44:32,769 +So I'm really gonna have to have eyesOpen via var + +891 +00:44:33,772 --> 00:44:38,341 +that has its own get and set. So + +892 +00:44:38,343 --> 00:44:42,745 +that in this set right here I can animate the setting, okay. + +893 +00:44:42,747 --> 00:44:46,015 +But I still need storage for the eyes open so here's what + +894 +00:44:46,017 --> 00:44:48,351 +I'm gonna do, this trick. If you ever find yourself in + +895 +00:44:48,353 --> 00:44:52,221 +a situation where you need to do something when something, + +896 +00:44:52,223 --> 00:44:55,024 +you need to animate the setting of something or + +897 +00:44:55,026 --> 00:44:57,493 +otherwise be Involved in the actual setting. + +898 +00:44:57,495 --> 00:45:00,530 +Not the react to the setting, this would didSet is for. + +899 +00:45:00,532 --> 00:45:03,800 +But you actually have to do the setting of it. And you ni, + +900 +00:45:03,802 --> 00:45:07,770 +make a public var like this that's computed. You can take + +901 +00:45:07,772 --> 00:45:09,906 +the storage and put an under bar in front of it. + +902 +00:45:09,908 --> 00:45:12,475 +That's kinda the convention we use to mean this is + +903 +00:45:12,477 --> 00:45:16,446 +the storage for another property that is computed. + +904 +00:45:16,448 --> 00:45:20,316 +Okay? We just call underbar. So I still have_eyesOpen. + +905 +00:45:20,318 --> 00:45:24,754 +It's just that I'm gonna set this, in here, animated. + +906 +00:45:24,756 --> 00:45:29,759 +Right? I'm gonna, say _eyesOpen = newValue in here. + +907 +00:45:29,761 --> 00:45:33,129 +But I'm gonna have to animate this happening. Now the get is + +908 +00:45:33,131 --> 00:45:36,799 +just return_eyesOpen I don't have to animate the getting of + +909 +00:45:36,801 --> 00:45:40,970 +this value. But this I have to animate. Okay, so I'm going to + +910 +00:45:40,972 --> 00:45:46,075 +animate this of course using UI view, transition with view. + +911 +00:45:46,077 --> 00:45:48,978 +Okay so here's transition, see there's the with view on and + +912 +00:45:48,980 --> 00:45:52,315 +here's the from view two view. So I'm going to use the with + +913 +00:45:52,317 --> 00:45:55,051 +view. And we'll do the same thing You do when there's + +914 +00:45:55,053 --> 00:45:58,354 +lots of arguments like this so you can see them all. + +915 +00:46:03,194 --> 00:46:07,096 +Okay, so we just have to animate the setting of this. + +916 +00:46:07,098 --> 00:46:12,301 +Now, let's start with the actual setting of this. That + +917 +00:46:12,303 --> 00:46:15,004 +happens here in this block. You see this animations block, + +918 +00:46:15,006 --> 00:46:17,673 +right here? So I'm just going to double click on this block. + +919 +00:46:17,675 --> 00:46:20,843 +Here it is. And I'm gonna put, what I want to happen, + +920 +00:46:20,845 --> 00:46:25,481 +inside here. See? So I'm animating this change. Okay. + +921 +00:46:25,483 --> 00:46:28,985 +This is gonna complain that this needs to be self. That's + +922 +00:46:28,987 --> 00:46:34,056 +because this is a closure. Okay? So we have to be clear. + +923 +00:46:34,058 --> 00:46:36,659 +Now, is there any problem with memory cycles here? + +924 +00:46:36,661 --> 00:46:40,563 +No, because this animation's only going to take + +925 +00:46:40,565 --> 00:46:42,532 +less than a second and this this closure will be gone, + +926 +00:46:42,534 --> 00:46:45,568 +so there's no worries about someone holding onto it and + +927 +00:46:45,570 --> 00:46:49,739 +it pointing back to us and keeping a cycle there. So + +928 +00:46:49,741 --> 00:46:53,976 +what view are we doing this in? We're doing this in self, + +929 +00:46:53,978 --> 00:46:57,780 +it's the eye view itself that's being animated, + +930 +00:46:57,782 --> 00:47:02,218 +it's being flipped over. And the time interval? Well, + +931 +00:47:02,220 --> 00:47:05,521 +we know that we close our eyes for 0.4, in 0.4 seconds, for + +932 +00:47:05,523 --> 00:47:09,192 +0.4 seconds. So, our time of causing the, + +933 +00:47:09,194 --> 00:47:11,160 +animating the change better be less than that. + +934 +00:47:11,162 --> 00:47:13,996 +So, maybe we'll say 0.2 seconds? + +935 +00:47:13,998 --> 00:47:16,866 +Something like that. We could play with these numbers. + +936 +00:47:16,868 --> 00:47:18,768 +Again, I should make a constant for this, but for + +937 +00:47:18,770 --> 00:47:22,004 +time, I won't do it. The animation options here, + +938 +00:47:22,006 --> 00:47:26,475 +we talked about. We want this transition, sure I find out + +939 +00:47:26,477 --> 00:47:29,312 +what it's called here. Transition flip from top, + +940 +00:47:29,314 --> 00:47:35,651 +I think it's called, yes. TransitionFlipFromTop, okay. + +941 +00:47:35,987 --> 00:47:38,221 +The addition, and we could put other ones in here. Maybe we, + +942 +00:47:38,223 --> 00:47:43,092 +you know, dot curve linear, or whatever. Put whatever + +943 +00:47:43,094 --> 00:47:48,064 +other options we want in here. And then completion. Once this + +944 +00:47:48,066 --> 00:47:51,734 +thing has closed we don't need to do anything. So + +945 +00:47:51,736 --> 00:47:57,540 +my completion here is nil. Everybody cool with that? + +946 +00:47:57,542 --> 00:48:04,347 +All right, let's see it work. All right, there it is. + +947 +00:48:04,349 --> 00:48:08,517 +So you see how the eyes kind of, see how they're kind of + +948 +00:48:08,519 --> 00:48:11,787 +squinching closed instead of jumping closed? + +949 +00:48:11,789 --> 00:48:18,461 +Yeah? All right. So it's getting better by the second. + +950 +00:48:18,463 --> 00:48:20,363 +All right, now let's do this head shake. + +951 +00:48:20,365 --> 00:48:22,131 +So now I want this little head to, to shake. + +952 +00:48:22,133 --> 00:48:24,667 +I don't know, to say, like he's saying no or something. + +953 +00:48:24,669 --> 00:48:26,702 +I'm not sure what. But let's do the head shake. So + +954 +00:48:26,704 --> 00:48:30,239 +the head shake, we're going to do by changing one of those + +955 +00:48:30,241 --> 00:48:31,274 +three special properties, + +956 +00:48:31,276 --> 00:48:34,110 +namely the transform. Okay, we're going to have + +957 +00:48:34,112 --> 00:48:35,945 +the transform of that thing changed. + +958 +00:48:35,947 --> 00:48:36,779 +And I'm gonna do that, mm, + +959 +00:48:36,781 --> 00:48:38,481 +I'm gonna do that in my FaceView right here. + +960 +00:48:38,483 --> 00:48:40,816 +Okay, it doesn't really have anything to do with blinking, + +961 +00:48:40,818 --> 00:48:42,285 +so there's no reason to put it there. So + +962 +00:48:42,287 --> 00:48:46,422 +I can put it in my FaceView. And so let's do it so that + +963 +00:48:46,424 --> 00:48:50,760 +it shakes its head when we tap on it. Right now, when we tap + +964 +00:48:50,762 --> 00:48:54,630 +on our FaceView, it does this, toggleEyes, right. If we + +965 +00:48:54,632 --> 00:48:56,365 +go look at our storyboard right here and + +966 +00:48:56,367 --> 00:48:59,201 +we look at this Tap Gesture Recognizer and right-click + +967 +00:48:59,203 --> 00:49:01,737 +on it, you see that toggleEye is doing toggleEyes in + +968 +00:49:01,739 --> 00:49:04,840 +our FaceViewController. So I'm gonna disconnect that and + +969 +00:49:04,842 --> 00:49:07,977 +create a new thing, which is gonna be a head shake. Okay, + +970 +00:49:07,979 --> 00:49:11,881 +so let's do a head shake. Now, I want to put head shake into + +971 +00:49:11,883 --> 00:49:14,917 +the FaceViewController superclass, okay? + +972 +00:49:14,919 --> 00:49:17,720 +I do not want head shake in BlinkingFaceViewController, + +973 +00:49:17,722 --> 00:49:20,389 +because it's not a blinking thing, it's nothing to do with + +974 +00:49:20,391 --> 00:49:23,559 +blinking, okay. But when I have this on automatic up + +975 +00:49:23,561 --> 00:49:27,763 +here, okay, it picks the BlinkingFaceViewController. + +976 +00:49:27,765 --> 00:49:33,970 +So how can I Ctrl+drag to put this in the superclass? + +977 +00:49:33,972 --> 00:49:36,772 +The answer is, just go to Manual. Okay, + +978 +00:49:36,774 --> 00:49:37,807 +if you go to Manual over here and + +979 +00:49:37,809 --> 00:49:41,243 +pick the FaceViewController and then you try to Ctrl+drag + +980 +00:49:41,245 --> 00:49:44,413 +in here, we'll put it right near toggle eyes, right here, + +981 +00:49:44,415 --> 00:49:49,018 +it's going to work. Because Xcode is smart enough to know + +982 +00:49:49,020 --> 00:49:51,921 +that even though this is a BlinkingFaceViewController + +983 +00:49:51,923 --> 00:49:56,058 +you're connecting it to one of its superclasses. + +984 +00:49:56,060 --> 00:50:00,129 +Okay, so we'll make a tap gesture action here, + +985 +00:50:00,131 --> 00:50:04,100 +we'll call it headShake. Okay, to tap gesture, right? + +986 +00:50:04,102 --> 00:50:08,571 +There's our tap gesture right there. Let's go ahead and + +987 +00:50:08,573 --> 00:50:11,374 +get the wider screen here. So, + +988 +00:50:11,376 --> 00:50:14,377 +like a real wide screen. All right, so here's headShake. + +989 +00:50:14,379 --> 00:50:15,778 +This is going to happen when we tap, + +990 +00:50:15,780 --> 00:50:19,448 +okay? So here's where we need to modify our transform, + +991 +00:50:19,450 --> 00:50:21,350 +and we want it, we know we want it to be animated, + +992 +00:50:21,352 --> 00:50:24,086 +so let's start right off the bat by doing our + +993 +00:50:24,088 --> 00:50:25,988 +UIView.animateWithDuration. Now, + +994 +00:50:25,990 --> 00:50:29,191 +you'll notice there's quite a few animateWithDurations here. + +995 +00:50:29,193 --> 00:50:34,296 +There's even one down here that has springiness in it so + +996 +00:50:34,298 --> 00:50:36,465 +that you can animate things springing, + +997 +00:50:36,467 --> 00:50:41,103 +things like that. But we're gonna pick the simplest one, + +998 +00:50:41,105 --> 00:50:44,373 +which is right here, almost [INAUDIBLE]. + +999 +00:50:44,375 --> 00:50:49,645 +Let's do the same thing where we put this on separate lines. + +1000 +00:50:50,481 --> 00:50:52,381 +All right, so here's our animateWithDuration. + +1001 +00:50:52,383 --> 00:50:56,619 +So here I am going to make a little private struct, struct, + +1002 +00:50:56,621 --> 00:51:01,090 +which I'm gonna have be my animation constants. And so + +1003 +00:51:01,092 --> 00:51:06,328 +let's do static let, let's have the ShakeAngle. So that's + +1004 +00:51:06,330 --> 00:51:09,398 +gonna be the angle of the head that we're going to shake, and + +1005 +00:51:09,400 --> 00:51:13,102 +we'll go, let's see. It's gonna be a CGFloat. It, + +1006 +00:51:13,104 --> 00:51:17,640 +let's go pi over 6. It's gonna be in radians, so we'll do pi + +1007 +00:51:17,642 --> 00:51:20,676 +over 6, which is a little bit of a head shake there. + +1008 +00:51:20,678 --> 00:51:24,380 +And then I'm also gonna have the shake duration, + +1009 +00:51:24,382 --> 00:51:27,616 +how long it takes to move. And for that one, + +1010 +00:51:27,618 --> 00:51:28,851 +let's do maybe half a second. + +1011 +00:51:28,853 --> 00:51:31,187 +So it's gonna do half a second to move each direction. + +1012 +00:51:31,189 --> 00:51:35,191 +So it'll take about a second a half to do the full shake, + +1013 +00:51:35,193 --> 00:51:39,161 +okay. So here, let's use our duration here, which is + +1014 +00:51:39,163 --> 00:51:43,032 +Animation.ShakeDuration. And here's + +1015 +00:51:43,034 --> 00:51:45,734 +our animation, okay, so we're gonna put our animation. This + +1016 +00:51:45,736 --> 00:51:48,871 +is where we're gonna change one of those three special + +1017 +00:51:48,873 --> 00:51:51,474 +things. And then here's our completion, + +1018 +00:51:51,476 --> 00:51:54,610 +which is gonna have this finished boolean and + +1019 +00:51:54,612 --> 00:51:58,314 +then some code here when we're finished, okay? + +1020 +00:51:58,316 --> 00:52:01,917 +And actually, in this case, I'm not going to, well, yeah. + +1021 +00:52:01,919 --> 00:52:05,121 +I'm not gonna use closing trailing syntax here. + +1022 +00:52:05,123 --> 00:52:07,857 +This is an interesting thing to talk about. So + +1023 +00:52:07,859 --> 00:52:11,527 +this is one of the few times when I don't like the trailing + +1024 +00:52:11,529 --> 00:52:14,730 +closure syntax here, because there's really nothing special + +1025 +00:52:14,732 --> 00:52:16,232 +about this closure versus this closure, + +1026 +00:52:16,234 --> 00:52:19,168 +they're kinda equal in power, maybe this one's even + +1027 +00:52:19,170 --> 00:52:22,138 +more powerful. So I'm gonna keep them all inside here, + +1028 +00:52:22,140 --> 00:52:26,308 +just kinda, to me, I think it reads a little better. But + +1029 +00:52:26,310 --> 00:52:26,675 +it's totally a style thing, + +1030 +00:52:26,677 --> 00:52:28,944 +whatever you wanna do. All right, so in here, + +1031 +00:52:28,946 --> 00:52:30,446 +we get to change one of these three things. Well, + +1032 +00:52:30,448 --> 00:52:34,917 +I'm gonna change the transform of this, of our FaceView. + +1033 +00:52:34,919 --> 00:52:35,518 +So I'm gonna say face, oops, + +1034 +00:52:35,520 --> 00:52:38,120 +and I'm gonna do self because I'm in a closure here. + +1035 +00:52:38,122 --> 00:52:42,224 +faceView.transform, and I'm gonna use this nice, + +1036 +00:52:42,226 --> 00:52:47,696 +function called CGAffineTransformRotate. + +1037 +00:52:47,698 --> 00:52:48,831 +It takes an existing transform, + +1038 +00:52:48,833 --> 00:52:52,568 +which I'm gonna take the FaceView's existing transform. + +1039 +00:52:52,570 --> 00:52:55,404 +Okay, transform, is, remember, it's just a var in UIView, + +1040 +00:52:55,406 --> 00:52:58,641 +that's all it is is a var, and it encapsulates the rotation, + +1041 +00:52:58,643 --> 00:53:01,010 +scaling, and translation, okay. So + +1042 +00:53:01,012 --> 00:53:04,346 +we're gonna be messing with the rotation here. And it's, + +1043 +00:53:04,348 --> 00:53:07,950 +we'll rotate it by this angle which we know is our + +1044 +00:53:07,952 --> 00:53:11,554 +Animation.Head, or, ShakeAngle. + +1045 +00:53:13,291 --> 00:53:17,660 +Okay? So that's going to do the rotation there. All right, + +1046 +00:53:17,662 --> 00:53:20,329 +let's see, what do we got here, what are we missing? + +1047 +00:53:20,331 --> 00:53:25,434 +Completion. Yeah, sorry. Completion. + +1048 +00:53:25,436 --> 00:53:28,470 +It's part of that trailing closure syntax, it deleted + +1049 +00:53:28,472 --> 00:53:31,774 +the last keyword. All right, so everyone cool with this? + +1050 +00:53:31,776 --> 00:53:35,644 +Now, what to do in here, we'll see later, okay. First we're + +1051 +00:53:35,646 --> 00:53:37,913 +gonna see if this is working at all. So we're gonna see, + +1052 +00:53:37,915 --> 00:53:40,382 +this is only doing the first part of the head shake, so + +1053 +00:53:40,384 --> 00:53:42,818 +let's see if that animation works. + +1054 +00:53:46,624 --> 00:53:48,257 +Okay, so our eyes, our eyes are still blinking, + +1055 +00:53:48,259 --> 00:53:51,527 +they're still doing the flip from top. And if we click, + +1056 +00:53:51,529 --> 00:53:54,830 +sure enough, it rotated it by pi over 6. + +1057 +00:53:54,832 --> 00:53:55,331 +In fact, if we click again, + +1058 +00:53:55,333 --> 00:53:58,367 +it'll keep on rotating. Now, notice the other animation + +1059 +00:53:58,369 --> 00:54:00,970 +keeps working completely independently. Okay, all + +1060 +00:54:00,972 --> 00:54:04,006 +animations, they, completely independent. They're only + +1061 +00:54:04,008 --> 00:54:06,842 +gonna start interacting with each other if you're animating + +1062 +00:54:06,844 --> 00:54:09,278 +the same thing, the same transform, the same alpha or + +1063 +00:54:09,280 --> 00:54:12,147 +whatever. Here these are completely different views, + +1064 +00:54:12,149 --> 00:54:15,217 +okay, and even though that view is being transformed, + +1065 +00:54:15,219 --> 00:54:17,319 +it still continued to flip from top, okay, + +1066 +00:54:17,321 --> 00:54:20,155 +which is kinda cool, it lets you make, lets you build + +1067 +00:54:20,157 --> 00:54:22,691 +your UI animation very object-oriented. Just make + +1068 +00:54:22,693 --> 00:54:26,462 +each piece animate however it wants to animate. Okay, but + +1069 +00:54:26,464 --> 00:54:29,064 +our head shake, it needs to turn back the other way and + +1070 +00:54:29,066 --> 00:54:31,100 +then back to the middle. So how are we gonna do that? + +1071 +00:54:31,102 --> 00:54:35,271 +Well, it can't turn back to the other side until it's + +1072 +00:54:35,273 --> 00:54:38,073 +finished turning to the right. Okay? So + +1073 +00:54:38,075 --> 00:54:42,311 +we're gonna use the completion block to animate it going back + +1074 +00:54:42,313 --> 00:54:44,847 +the other way. So as soon as it's finished, if it's + +1075 +00:54:44,849 --> 00:54:50,052 +successfully moved over, if it finished. If it finished, + +1076 +00:54:50,054 --> 00:54:51,387 +then we're gonna animate back. + +1077 +00:54:51,389 --> 00:54:53,722 +Well, how the heck are we gonna animate back? Well, + +1078 +00:54:53,724 --> 00:54:57,593 +let's just copy and paste this, because we know this, + +1079 +00:54:57,595 --> 00:55:00,162 +right, this whole thing right here does an animation. So + +1080 +00:55:00,164 --> 00:55:02,798 +we wanna do almost the exact same animation. I'm just gonna + +1081 +00:55:02,800 --> 00:55:06,368 +copy and paste it right in there. The only difference is + +1082 +00:55:06,370 --> 00:55:08,637 +that instead of the shake angle going to the right, + +1083 +00:55:08,639 --> 00:55:13,108 +now it wants to go backwards times two. Okay, it wants to + +1084 +00:55:13,110 --> 00:55:16,512 +go all the way back past the middle and to the other side. + +1085 +00:55:16,514 --> 00:55:18,981 +And then sure enough, when that one's finished, + +1086 +00:55:18,983 --> 00:55:21,383 +we want to do it again and get back to the middle. + +1087 +00:55:21,385 --> 00:55:24,486 +So we're just doing three transforms here, and + +1088 +00:55:24,488 --> 00:55:28,457 +we're just chaining them, okay, in the completion blocks + +1089 +00:55:28,459 --> 00:55:32,494 +of each of them, we're just doing the next animation. That + +1090 +00:55:32,496 --> 00:55:35,431 +make sense? Right? So that's how we chain animations. + +1091 +00:55:35,433 --> 00:55:40,969 +So let's see if that works. All right? + +1092 +00:55:40,971 --> 00:55:42,638 +So, here we go, he's blinking, and + +1093 +00:55:42,640 --> 00:55:48,143 +he shakes his head. And again, we could play with this, + +1094 +00:55:48,145 --> 00:55:51,313 +do we want to curve in, ease in, ease out. Do we want to + +1095 +00:55:51,315 --> 00:55:53,682 +take a little longer maybe to swing back over. + +1096 +00:55:53,684 --> 00:55:57,186 +And so you can play with those numbers really easy in here + +1097 +00:55:57,188 --> 00:56:00,489 +just by setting options or Or durations. I didn't use + +1098 +00:56:00,491 --> 00:56:03,692 +the version of animate durations that had the options + +1099 +00:56:03,694 --> 00:56:07,296 +as an argument, but you could certainly add that back in, + +1100 +00:56:07,298 --> 00:56:10,165 +okay? Any questions about that? You getting a good feel + +1101 +00:56:10,167 --> 00:56:15,304 +for this whole UI view based animation? All right. Okay, + +1102 +00:56:15,306 --> 00:56:21,043 +in the time we have remaining here, hopefully I can get + +1103 +00:56:21,045 --> 00:56:26,815 +us going on this next kind of animation which is this + +1104 +00:56:26,817 --> 00:56:30,119 +physic based one. So now let's talk more about animation. + +1105 +00:56:30,121 --> 00:56:31,954 +We're gonna talk about dynamic animation, + +1106 +00:56:31,956 --> 00:56:35,557 +which is this physics based animation and it's a little + +1107 +00:56:35,559 --> 00:56:37,626 +different approach than the UIView-based. The + +1108 +00:56:37,628 --> 00:56:40,229 +UIView-based, your pretty much directly changing the things + +1109 +00:56:40,231 --> 00:56:42,931 +you wanna change and then animating that change, okay. + +1110 +00:56:42,933 --> 00:56:45,868 +Here you're just describing how things interact and + +1111 +00:56:45,870 --> 00:56:49,304 +then letting them go, okay? However they, they wanna go + +1112 +00:56:49,306 --> 00:56:53,208 +based on whatever restrictions and physics you put upon them, + +1113 +00:56:53,210 --> 00:56:56,145 +okay? So, here's how you do dynamic animation, here's + +1114 +00:56:56,147 --> 00:56:59,348 +the steps. One, you're gonna create a UIDynamicAnimator. + +1115 +00:56:59,350 --> 00:57:01,750 +This is the thing that does the animation. Very simple + +1116 +00:57:01,752 --> 00:57:05,421 +object to create, it, but very powerful implementation, + +1117 +00:57:05,423 --> 00:57:07,890 +it's the thing that actually is doing the animation. + +1118 +00:57:07,892 --> 00:57:11,493 +Then you're gonna create UIDynamicBehaviors and + +1119 +00:57:11,495 --> 00:57:15,397 +add them to the animator. Behaviors are things like, + +1120 +00:57:15,399 --> 00:57:19,334 +gravity is a behavior. Collisions are a behavior. + +1121 +00:57:19,336 --> 00:57:22,438 +Pushing things is a behavior, okay? + +1122 +00:57:22,440 --> 00:57:25,140 +Then you're gonna add UIDynamicItems, which + +1123 +00:57:25,142 --> 00:57:28,911 +are usually UIViews, but not always, but 90% of the time. + +1124 +00:57:28,913 --> 00:57:32,047 +You're gonna add those to the behaviors, and that's gonna + +1125 +00:57:32,049 --> 00:57:34,516 +make those behaviors start acting on those items, + +1126 +00:57:34,518 --> 00:57:36,852 +okay? So it's a three way thing there. Items get + +1127 +00:57:36,854 --> 00:57:39,721 +added to behaviors, behaviors get added to the animator and + +1128 +00:57:39,723 --> 00:57:41,190 +as soon as those are all hooked up, + +1129 +00:57:41,192 --> 00:57:43,225 +things will just start moving, okay? + +1130 +00:57:43,227 --> 00:57:44,393 +Nothing else, you don't need to say go. + +1131 +00:57:44,395 --> 00:57:46,128 +It just automatically goes. As soon as you add it, + +1132 +00:57:46,130 --> 00:57:50,199 +it starts going. All right, so let's talk about each of those + +1133 +00:57:50,201 --> 00:57:52,734 +steps. First creating the dynamic animator, + +1134 +00:57:52,736 --> 00:57:56,605 +there's only two initializers of it. One takes no arguments, + +1135 +00:57:56,607 --> 00:57:58,407 +that just creates a dynamic animator. But + +1136 +00:57:58,409 --> 00:58:02,044 +if you're animating views, if the UIDynamic items you want + +1137 +00:58:02,046 --> 00:58:05,447 +to animate are views, then you're going to want to create + +1138 +00:58:05,449 --> 00:58:09,084 +it with a referenceView, okay? And that's just gonna be like + +1139 +00:58:09,086 --> 00:58:12,521 +your top level view, usually, where all the animation is + +1140 +00:58:12,523 --> 00:58:16,225 +happening. All right? So that's it. + +1141 +00:58:16,227 --> 00:58:16,291 +That's easy, + +1142 +00:58:16,293 --> 00:58:19,127 +it couldn't be easier creating a UIDynamicAnimator. + +1143 +00:58:19,129 --> 00:58:21,964 +Next you're gonna create the DynamicBehaviors, okay. + +1144 +00:58:21,966 --> 00:58:23,532 +The behaviors, generally you create, + +1145 +00:58:23,534 --> 00:58:27,002 +their initializers take no arguments, okay? And so + +1146 +00:58:27,004 --> 00:58:30,439 +you just create them, and add them to the animator here + +1147 +00:58:30,441 --> 00:58:32,608 +using addBehavior, this addBehavior method. + +1148 +00:58:32,610 --> 00:58:36,378 +Now, oftentimes, you'll create something like gravity or + +1149 +00:58:36,380 --> 00:58:38,647 +the collider there and you're going to configure it. + +1150 +00:58:38,649 --> 00:58:41,350 +Because the gravity can be strong gravity or light + +1151 +00:58:41,352 --> 00:58:43,785 +gravity, like Martian gravity or Earth gravity, okay? + +1152 +00:58:43,787 --> 00:58:46,455 +You can change that. Same thing with collider obviously. + +1153 +00:58:46,457 --> 00:58:49,391 +You've got to decide what's gonna collide with what, okay? + +1154 +00:58:49,393 --> 00:58:52,461 +But once you create them, you're going to just add them + +1155 +00:58:52,463 --> 00:58:54,730 +to the animator using addBehavior. And + +1156 +00:58:54,732 --> 00:58:58,200 +then you add the dynamic items to the behavior and you do + +1157 +00:58:58,202 --> 00:59:01,703 +that with addItem on the behavior. So gravity.addItem, + +1158 +00:59:01,705 --> 00:59:04,573 +collider.addItem, gravity.addItem 2. Now if you + +1159 +00:59:04,575 --> 00:59:08,010 +did these three things right here, notice that item1 and + +1160 +00:59:08,012 --> 00:59:11,213 +item2 would both be affected by gravity cuz I added them to + +1161 +00:59:11,215 --> 00:59:15,450 +that. But notice that item2 would not collide with item1. + +1162 +00:59:15,452 --> 00:59:18,887 +If item2 and item1 came, next to each other on screen, + +1163 +00:59:18,889 --> 00:59:21,456 +they'd pass right through because they're not + +1164 +00:59:21,458 --> 00:59:25,661 +both being affected by the same collider, okay? + +1165 +00:59:25,663 --> 00:59:26,895 +Now if I said collider add item2, + +1166 +00:59:26,897 --> 00:59:29,264 +then they would smash into each other and + +1167 +00:59:29,266 --> 00:59:34,102 +bounce off, okay? So, which, behaviors you add, which + +1168 +00:59:34,104 --> 00:59:38,040 +items to really determines how they're gonna interact. + +1169 +00:59:38,042 --> 00:59:40,609 +All right, so UIDynamicItem, I keep mentioning this. + +1170 +00:59:40,611 --> 00:59:43,612 +What is this? I said that usually this would be views, + +1171 +00:59:43,614 --> 00:59:48,450 +UIViews. But UIDynamicItem is actually a protocol, okay? And + +1172 +00:59:48,452 --> 00:59:52,254 +it has these three vars in it, bounds, which is the bounds of + +1173 +00:59:52,256 --> 00:59:57,626 +the thing being animated, notice that that is get only, + +1174 +00:59:57,628 --> 01:00:03,699 +okay? You cannot animate the bounds of something + +1175 +01:00:03,701 --> 01:00:07,536 +in the animator. However, you can animate the center, + +1176 +01:00:07,538 --> 01:00:09,805 +which is where it is, because that one is get and + +1177 +01:00:09,807 --> 01:00:13,575 +set, okay? So the position of something in the animation + +1178 +01:00:13,577 --> 01:00:16,078 +world is animatable, but not the bounds. In other words, + +1179 +01:00:16,080 --> 01:00:21,550 +not the size, okay? However, the transform which + +1180 +01:00:21,552 --> 01:00:26,355 +views have is settable. So you can rotate things, okay? + +1181 +01:00:26,357 --> 01:00:31,293 +And scale them, things like that, as part of the animation + +1182 +01:00:31,295 --> 01:00:35,464 +as well. So, this like I said, is usually a UIView but + +1183 +01:00:35,466 --> 01:00:37,899 +you could actually animate off screen things or + +1184 +01:00:37,901 --> 01:00:40,469 +things that you draw on screen using sprites or + +1185 +01:00:40,471 --> 01:00:45,741 +something else, using this whole mechanism as well, okay. + +1186 +01:00:45,743 --> 01:00:48,243 +But in this class you are only gonna do UIViews, + +1187 +01:00:48,245 --> 01:00:51,213 +it's the most straightforward obvious way to do it. + +1188 +01:00:51,215 --> 01:00:53,248 +Now if you think about these being UIViews, and + +1189 +01:00:53,250 --> 01:00:55,250 +they've been added to all these behaviors. And + +1190 +01:00:55,252 --> 01:00:57,719 +gravity is pulling on them, and they're colliding on, + +1191 +01:00:57,721 --> 01:01:00,088 +off each other and bouncing and moving all around. + +1192 +01:01:00,090 --> 01:01:02,591 +Maybe they're spinning around because they hit a corner or + +1193 +01:01:02,593 --> 01:01:05,327 +something. Their transform is being changed. + +1194 +01:01:05,329 --> 01:01:08,296 +If you want to change any of those views, if you want to + +1195 +01:01:08,298 --> 01:01:12,100 +change their transform or center, okay. Then you have to + +1196 +01:01:12,102 --> 01:01:15,270 +let the animator know, otherwise, it's gonna be + +1197 +01:01:15,272 --> 01:01:17,939 +changing them to something else. And you do that + +1198 +01:01:17,941 --> 01:01:20,442 +by sending this message to the animator which is + +1199 +01:01:20,444 --> 01:01:23,578 +updateItemUsingCurrentState. When you pass the item, this + +1200 +01:01:23,580 --> 01:01:27,115 +would be a UIView, right, cuz UIView implements in protocol. + +1201 +01:01:27,117 --> 01:01:30,485 +And, then it will pick up whatever the current state is. + +1202 +01:01:30,487 --> 01:01:33,622 +So if you move the view to a certain spot the animator + +1203 +01:01:33,624 --> 01:01:36,291 +which moved the item to the spot in its world and + +1204 +01:01:36,293 --> 01:01:40,395 +then keep applying all the behaviors to it, okay? But + +1205 +01:01:40,397 --> 01:01:41,229 +it you don't do this, + +1206 +01:01:41,231 --> 01:01:43,665 +you're gonna be fighting the animator. Okay, + +1207 +01:01:43,667 --> 01:01:46,902 +so don't fight the animator, work with the animator. + +1208 +01:01:47,638 --> 01:01:49,471 +Okay, so let's talk about some of these behaviors in + +1209 +01:01:49,473 --> 01:01:54,276 +detail here. Gravity behavior, so gravity isn't always down. + +1210 +01:01:54,278 --> 01:01:56,978 +Okay, gravity can mean any direction you want. Okay, + +1211 +01:01:56,980 --> 01:02:00,415 +you specify the direction with this angle right here, + +1212 +01:02:00,417 --> 01:02:05,020 +angles in radians, 0 is off to the right. So if you set your + +1213 +01:02:05,022 --> 01:02:08,056 +gravity angle to 0 and put some views on there, as long + +1214 +01:02:08,058 --> 01:02:10,025 +as your magnitude is greater than 0 everything starts + +1215 +01:02:10,027 --> 01:02:13,528 +sliding off, accelerating off, cuz gravity is acceleration. + +1216 +01:02:13,530 --> 01:02:14,529 +Right everyone know what gravity is? + +1217 +01:02:14,531 --> 01:02:17,432 +It's acceleration of gravity, 9.8 meters per second squared, + +1218 +01:02:17,434 --> 01:02:19,634 +right? So it's gonna start accelerating + +1219 +01:02:19,636 --> 01:02:22,237 +off to the right. So if you wanted it going down, + +1220 +01:02:22,239 --> 01:02:25,507 +let's say, down towards the home button, + +1221 +01:02:25,509 --> 01:02:29,978 +then you would want it to be what, three pi over two or + +1222 +01:02:29,980 --> 01:02:32,147 +something like that? Yeah, three pi over two I guess, + +1223 +01:02:32,149 --> 01:02:34,549 +I know my radians. Cuz you want it pointing all the way + +1224 +01:02:34,551 --> 01:02:38,653 +to down, okay. We're gonna talk about next week, + +1225 +01:02:38,655 --> 01:02:42,090 +what if you wanted it pointing where real gravity was. And + +1226 +01:02:42,092 --> 01:02:43,792 +once you know core motion, and you know how to use + +1227 +01:02:43,794 --> 01:02:46,061 +the accelerometer that's in the device you could actually + +1228 +01:02:46,063 --> 01:02:49,631 +be constantly setting this gravity to be actual gravity. + +1229 +01:02:49,633 --> 01:02:51,166 +And so all your things could fall and + +1230 +01:02:51,168 --> 01:02:52,067 +no matter way they turn their phone, + +1231 +01:02:52,069 --> 01:02:55,871 +things could fall down towards the Earth. And then magnitude + +1232 +01:02:55,873 --> 01:02:59,574 +is how, how fast the acceleration is happening. + +1233 +01:02:59,576 --> 01:03:00,375 +What's interesting is 1.0, + +1234 +01:03:00,377 --> 01:03:05,580 +the magnitude of 1.0 is 1000 points per second squared. + +1235 +01:03:05,582 --> 01:03:07,883 +Okay, it's accelerating 1000 points a second, + +1236 +01:03:07,885 --> 01:03:10,819 +per second, that's how fast it's accelerating. + +1237 +01:03:10,821 --> 01:03:15,423 +This looks amazingly like 9.8 meters per second squared. + +1238 +01:03:15,425 --> 01:03:17,959 +Okay, if you put something the top of your screen and + +1239 +01:03:17,961 --> 01:03:20,595 +let it fall at this magnitude, it'll fall + +1240 +01:03:20,597 --> 01:03:23,632 +very similar to how a real object would fall in space. + +1241 +01:03:23,634 --> 01:03:26,101 +And it's amazing that this round number is so + +1242 +01:03:26,103 --> 01:03:30,906 +close to 9.8 meters per second squared. But it's not, + +1243 +01:03:30,908 --> 01:03:34,309 +it's not the same thing, but it's close. All right, + +1244 +01:03:34,311 --> 01:03:36,945 +UI attachment behaviors. So what is this behavior? + +1245 +01:03:36,947 --> 01:03:40,749 +This behavior allows you to take two items or an item and + +1246 +01:03:40,751 --> 01:03:43,351 +a point and attach them. Basically attach + +1247 +01:03:43,353 --> 01:03:45,253 +them with like an iron bar between them. But + +1248 +01:03:45,255 --> 01:03:49,157 +the bar can pivot at either side, either at the point or + +1249 +01:03:49,159 --> 01:03:51,793 +at the item or at the two items can pivot. + +1250 +01:03:51,795 --> 01:03:53,762 +So basically if you wanna think about two items, + +1251 +01:03:53,764 --> 01:03:56,164 +those two items will always stay the same distance apart + +1252 +01:03:56,166 --> 01:03:59,467 +no matter what's happening to them. Okay? Now, if you had + +1253 +01:03:59,469 --> 01:04:02,604 +a point, a fixed point, in an item, and this item had + +1254 +01:04:02,606 --> 01:04:05,507 +gravity and an attachment behavior going onto it, + +1255 +01:04:05,509 --> 01:04:09,511 +it would fall down and swing. See why? Cuz it's always + +1256 +01:04:09,513 --> 01:04:11,847 +attached to this point, but gravity is pulling it down, + +1257 +01:04:11,849 --> 01:04:15,851 +and eventually it would settle down. That make sense? So + +1258 +01:04:15,853 --> 01:04:18,086 +attachment is basically a way to attach two things, or + +1259 +01:04:18,088 --> 01:04:19,788 +attach something to a point. Now, what's + +1260 +01:04:19,790 --> 01:04:23,558 +really cool about it is, while things are happening, you can + +1261 +01:04:23,560 --> 01:04:26,328 +change the length of that attachment. Okay? + +1262 +01:04:26,330 --> 01:04:29,231 +Right, right in the middle, so it's falling down, + +1263 +01:04:29,233 --> 01:04:32,534 +you could just pull it up in close. Like a yo-yo. Right? + +1264 +01:04:32,536 --> 01:04:34,502 +If you're doing yo-yo, you throw it around, and + +1265 +01:04:34,504 --> 01:04:37,772 +you start pulling in, while it's still turning? Okay. + +1266 +01:04:37,774 --> 01:04:38,039 +You can do the same thing. + +1267 +01:04:38,041 --> 01:04:41,977 +You could build Yoyo quite easily here, by changing + +1268 +01:04:41,979 --> 01:04:45,981 +the length of the attachment. Okay, the anchor point, okay, + +1269 +01:04:45,983 --> 01:04:48,083 +if you have a point and an item, that can also change. + +1270 +01:04:48,085 --> 01:04:50,085 +It's like maybe it's attached to the finger, + +1271 +01:04:50,087 --> 01:04:52,821 +using a gesture. And you're moving your finger around and + +1272 +01:04:52,823 --> 01:04:55,790 +the attachment changing, is pulling the thing around with + +1273 +01:04:55,792 --> 01:04:57,893 +it. Okay, and I'm actually going to show that. + +1274 +01:04:57,895 --> 01:05:00,795 +In the demo on Wednesday. So there's a lot of power in + +1275 +01:05:00,797 --> 01:05:04,232 +an attachment behavior. Collision behaviors. + +1276 +01:05:04,234 --> 01:05:06,468 +Another thing,obviously, that you want. Right? + +1277 +01:05:06,470 --> 01:05:09,237 +Let's say you're gonna build your homework six which is + +1278 +01:05:09,239 --> 01:05:11,706 +a breakout game. Okay? Obviously the breakout game + +1279 +01:05:11,708 --> 01:05:14,175 +wants to collide with the bricks and knock them out, and + +1280 +01:05:14,177 --> 01:05:16,411 +wants to bounce of the edge and bounce off the paddle. + +1281 +01:05:16,413 --> 01:05:19,814 +So you need these collisions, right? There you can either + +1282 +01:05:19,816 --> 01:05:22,317 +have things colliding off of boundaries so + +1283 +01:05:22,319 --> 01:05:25,053 +like in your breakout game the bricks would probably be these + +1284 +01:05:25,055 --> 01:05:27,422 +fixed boundaries. Okay your paddle's probably + +1285 +01:05:27,424 --> 01:05:29,791 +a boundary that you're moving all right or + +1286 +01:05:29,793 --> 01:05:32,427 +it can bounce off other things that are being animated. + +1287 +01:05:32,429 --> 01:05:34,996 +Although you wouldn't want your bricks to do that because + +1288 +01:05:34,998 --> 01:05:36,331 +your bricks when you hit them they disappear. + +1289 +01:05:36,333 --> 01:05:39,467 +They don't go flying off the screen okay they They despair + +1290 +01:05:39,469 --> 01:05:42,270 +well maybe would have a flat screen, I don't know. + +1291 +01:05:42,272 --> 01:05:46,741 +So collision lets you set up collisions between boundaries + +1292 +01:05:46,743 --> 01:05:51,379 +or between items, okay. You can have as many items as you + +1293 +01:05:51,381 --> 01:05:52,981 +want in there, things all bouncing off each other, + +1294 +01:05:52,983 --> 01:05:54,582 +the demo I'm going to do on Wednesday we're gonna have + +1295 +01:05:54,584 --> 01:05:57,352 +a lot of things colliding with each other. + +1296 +01:05:57,354 --> 01:05:58,320 +There's a nice little var here, + +1297 +01:05:58,322 --> 01:06:01,423 +a bool translates reference bounce into boundary. And + +1298 +01:06:01,425 --> 01:06:04,693 +what that'll do it'll make a boundary which is the edge + +1299 +01:06:04,695 --> 01:06:06,828 +of your animator's reference view right? + +1300 +01:06:06,830 --> 01:06:09,264 +So the reference view remember at the beginning of this that + +1301 +01:06:09,266 --> 01:06:10,899 +kind of contains the whole space. + +1302 +01:06:10,901 --> 01:06:13,134 +You can make it so that it's basically a box. So everything + +1303 +01:06:13,136 --> 01:06:16,104 +that happens in the animation world as long as you add it to + +1304 +01:06:16,106 --> 01:06:21,676 +this collision behavior will stay inside that box okay? + +1305 +01:06:22,579 --> 01:06:25,280 +One thing that's nice to know about the collision is when + +1306 +01:06:25,282 --> 01:06:27,882 +a collision happens. And the collision behavior has + +1307 +01:06:27,884 --> 01:06:31,886 +a delegate, okay, which lets you find out when a collision + +1308 +01:06:31,888 --> 01:06:34,689 +happens. So you get this delegate method sent to you + +1309 +01:06:34,691 --> 01:06:37,926 +collision behavior. Here's the behavior that sent me to you. + +1310 +01:06:37,928 --> 01:06:41,162 +And it'll tell you that contact began or ended for + +1311 +01:06:41,164 --> 01:06:45,000 +an item with a boundary, or for an item with another item. + +1312 +01:06:45,002 --> 01:06:48,837 +So there's the thing with item as well. Notice + +1313 +01:06:48,839 --> 01:06:54,009 +the type of this with boundary identifier. NScopying okay. + +1314 +01:06:54,011 --> 01:06:59,614 +NScopying is there for historical reasons but + +1315 +01:06:59,616 --> 01:07:01,216 +suffice it to say NSstring and + +1316 +01:07:01,218 --> 01:07:05,387 +NSnumber are what's intended to be passed there. And + +1317 +01:07:05,389 --> 01:07:07,789 +we know that those are bridged to string and Int and + +1318 +01:07:07,791 --> 01:07:10,892 +Double, nicely bridged. So you can pass strings and doubles, + +1319 +01:07:10,894 --> 01:07:14,829 +the only tricky thing is that you're gonna have to use as + +1320 +01:07:14,831 --> 01:07:18,133 +to cast this to be a string or an Int or a Double okay + +1321 +01:07:18,135 --> 01:07:24,139 +because it's an NSCopying. Small quirk of the API there. + +1322 +01:07:24,141 --> 01:07:27,242 +Next behavior is SnapBehavior. This is how you move something + +1323 +01:07:27,244 --> 01:07:29,944 +to a new location. So, you got something sitting there and + +1324 +01:07:29,946 --> 01:07:31,813 +you want it, move it over here, okay. + +1325 +01:07:31,815 --> 01:07:35,316 +And, it's called SnapBehavior because it moves over there + +1326 +01:07:35,318 --> 01:07:38,219 +but when it gets there it's like it's attached with + +1327 +01:07:38,221 --> 01:07:41,022 +four springs to its corners so that it gets there and + +1328 +01:07:41,024 --> 01:07:44,359 +goes [NOISE]. It vibrates a little bit. It doesn't just + +1329 +01:07:44,361 --> 01:07:48,863 +slide up and get stuck. It slides kind of softly. + +1330 +01:07:48,865 --> 01:07:51,566 +You can say how much the springs are dampened, + +1331 +01:07:51,568 --> 01:07:53,334 +whether it really shakes when it gets there, or + +1332 +01:07:53,336 --> 01:07:56,738 +if you get a slight shake or whatever. But snap behavior's + +1333 +01:07:56,740 --> 01:07:59,741 +kinda the preferred way to move something from one place + +1334 +01:07:59,743 --> 01:08:02,811 +to another, okay. Now a lot of things might be moving cuz + +1335 +01:08:02,813 --> 01:08:05,213 +they have gravity and other things bouncing on them. But + +1336 +01:08:05,215 --> 01:08:06,714 +sometimes you have a stationary thing that you want + +1337 +01:08:06,716 --> 01:08:10,151 +to move and snap behavior is a good way to do that. + +1338 +01:08:10,153 --> 01:08:13,588 +Then there's push behavior, okay. Push behavior means push + +1339 +01:08:13,590 --> 01:08:16,891 +on this thing, okay, and you can either push it once and + +1340 +01:08:16,893 --> 01:08:20,829 +see what happens to it or you can continue to push on it, + +1341 +01:08:20,831 --> 01:08:25,633 +okay. So that's continuous versus instantaneous pushing. + +1342 +01:08:25,635 --> 01:08:27,502 +And you just specify the direction or + +1343 +01:08:27,504 --> 01:08:30,472 +you can do an angle and a magnitude kind of like you + +1344 +01:08:30,474 --> 01:08:33,007 +do with gravity and it's going to push in that direction. + +1345 +01:08:33,009 --> 01:08:34,843 +So, for example, let's say you had a view, and + +1346 +01:08:34,845 --> 01:08:36,878 +gravity is working on it, so it's falling down the screen, + +1347 +01:08:36,880 --> 01:08:39,447 +and you pushed up on it with a certain amount of force. + +1348 +01:08:39,449 --> 01:08:42,684 +It would fly back up, but then gravity would still be working + +1349 +01:08:42,686 --> 01:08:43,585 +on it, so it would come back down. + +1350 +01:08:43,587 --> 01:08:46,888 +See what I mean? So pushing imparts a certain + +1351 +01:08:46,890 --> 01:08:50,492 +force to it, but if it's an instantaneous push it's not + +1352 +01:08:50,494 --> 01:08:52,694 +going to apply that force after the initial push and + +1353 +01:08:52,696 --> 01:08:57,065 +other forces are going to continue to work on it. Right. + +1354 +01:08:57,067 --> 01:08:57,565 +Okay? + +1355 +01:08:57,567 --> 01:09:01,669 +Now it's an interesting about push behaviors is that if + +1356 +01:09:01,671 --> 01:09:05,140 +they're instantaneous once you push on them you kind of want + +1357 +01:09:05,142 --> 01:09:07,208 +to remove them as behaviors cuz they're dead. + +1358 +01:09:07,210 --> 01:09:09,077 +They're never gonna push again. And + +1359 +01:09:09,079 --> 01:09:10,378 +instance behavior only and + +1360 +01:09:10,380 --> 01:09:12,147 +instantaneous behavior only pushes one and + +1361 +01:09:12,149 --> 01:09:15,650 +then it's done so you want to really remove that behavior. + +1362 +01:09:15,652 --> 01:09:18,887 +And doing that you kind of do that in an unusual way. + +1363 +01:09:18,889 --> 01:09:20,255 +And I'm gonna talk about that in a few slides, + +1364 +01:09:20,257 --> 01:09:25,193 +after I talk about a different method in a second. Then + +1365 +01:09:25,195 --> 01:09:27,695 +there's this behavior. Okay, we're talking about behaviors, + +1366 +01:09:27,697 --> 01:09:28,863 +right, for gravity and collisions. + +1367 +01:09:28,865 --> 01:09:30,965 +Here's one called UIDynamicItemBehavior. + +1368 +01:09:30,967 --> 01:09:33,635 +And this is kind of a meta behavior, okay. + +1369 +01:09:33,637 --> 01:09:37,038 +This has a bunch of vars like allowsRotation, friction, + +1370 +01:09:37,040 --> 01:09:41,209 +elasticity. These are settings that you make, okay, that, so + +1371 +01:09:41,211 --> 01:09:43,845 +all the items that are added to this behavior will kind of + +1372 +01:09:43,847 --> 01:09:48,416 +have these attributes. Okay. They'll be allowed to rotate, + +1373 +01:09:48,418 --> 01:09:48,650 +they'll have a certain friction. + +1374 +01:09:48,652 --> 01:09:52,220 +They'll have a certain elasticity when they bounce of + +1375 +01:09:52,222 --> 01:09:56,191 +other things, okay? So these are really kind of effect, + +1376 +01:09:56,193 --> 01:10:01,196 +affecting other behaviors. Behaviors. + +1377 +01:10:01,198 --> 01:10:04,632 +So you can think of this as a configuration behavior. + +1378 +01:10:04,634 --> 01:10:08,169 +You really are probably only going to have one. + +1379 +01:10:08,171 --> 01:10:10,338 +Each item will in one item behavior. + +1380 +01:10:10,340 --> 01:10:12,974 +It is actually legal to have multiple item + +1381 +01:10:12,976 --> 01:10:16,144 +behaviors on same items. But you better be sure that you + +1382 +01:10:16,146 --> 01:10:18,846 +understand how they are interacting with each other. + +1383 +01:10:18,848 --> 01:10:22,951 +Generally though we think of them as just settings. For + +1384 +01:10:22,953 --> 01:10:25,286 +the items, how they're gonna behave with collisions and + +1385 +01:10:25,288 --> 01:10:28,356 +all these other things. The UIDynamicItemBehavior, + +1386 +01:10:28,358 --> 01:10:29,424 +you almost always have one, by the way, + +1387 +01:10:29,426 --> 01:10:32,026 +cuz you want to set these things. It's also really cool, + +1388 +01:10:32,028 --> 01:10:34,596 +because you can ask the dynamic item behavior for + +1389 +01:10:34,598 --> 01:10:36,731 +any item that's added to that behavior. + +1390 +01:10:36,733 --> 01:10:40,735 +You can say, what's its current linear velocity? + +1391 +01:10:40,737 --> 01:10:43,671 +I got some viewage bouncing along the screen because it + +1392 +01:10:43,673 --> 01:10:46,441 +collided and gravity's pulling on it and + +1393 +01:10:46,443 --> 01:10:47,675 +I want to know what's it's velocity? + +1394 +01:10:47,677 --> 01:10:50,278 +Right now at this instant, how fast is it moving and in what + +1395 +01:10:50,280 --> 01:10:53,681 +direction? Okay, so that's really nice to know especially + +1396 +01:10:53,683 --> 01:10:56,818 +if you're gonna pause your game. Or pause what's going on + +1397 +01:10:56,820 --> 01:11:00,388 +and then continue. You want to grab its linear velocity, + +1398 +01:11:00,390 --> 01:11:03,324 +stop the animation and when it starts again set the linear + +1399 +01:11:03,326 --> 01:11:06,527 +velocity back to what it was, cause you can set it as well, + +1400 +01:11:06,529 --> 01:11:08,263 +by adding linear velocity back in. + +1401 +01:11:08,265 --> 01:11:11,099 +You can also find angular velocity, if the thing is + +1402 +01:11:11,101 --> 01:11:14,269 +spinning, k how fast it's spinning, spinning really fast + +1403 +01:11:14,271 --> 01:11:19,274 +or just kind of slowly rotating, whatever okay. + +1404 +01:11:20,110 --> 01:11:23,177 +UI dynamic behavior as opposed to UI dynamic + +1405 +01:11:23,179 --> 01:11:25,680 +item behavior the last I was here UI dynamic item behavior. + +1406 +01:11:25,682 --> 01:11:28,650 +This is UI dynamic behavior. This is the super class of all + +1407 +01:11:28,652 --> 01:11:33,621 +behaviors okay? And you can create your own behaviors as + +1408 +01:11:33,623 --> 01:11:38,393 +a composite of other behaviors by using this addChildBehavior + +1409 +01:11:38,395 --> 01:11:40,895 +method and UIDynamicBehavior. So you simply + +1410 +01:11:40,897 --> 01:11:44,699 +subclass UIDynamicBehavior, addChildBehavior for + +1411 +01:11:44,701 --> 01:11:47,402 +all the composite behaviors you want. The gravity and + +1412 +01:11:47,404 --> 01:11:50,605 +the dynamic item behaviors and collision, whatever. + +1413 +01:11:50,607 --> 01:11:51,639 +You add all those child behaviors. + +1414 +01:11:51,641 --> 01:11:55,543 +And then add any items to all of those behaviors, and you've + +1415 +01:11:55,545 --> 01:11:59,213 +created a composite new kind of behavior, which collects + +1416 +01:11:59,215 --> 01:12:02,250 +all those into one. And if we have some set of behaviors + +1417 +01:12:02,252 --> 01:12:05,119 +that's operating on a whole bunch of items, we are very + +1418 +01:12:05,121 --> 01:12:08,056 +often going to create our own little composite subclass. + +1419 +01:12:08,058 --> 01:12:11,159 +And I'll do that in the demo cuz it's pretty common, okay? + +1420 +01:12:11,161 --> 01:12:14,962 +One thing that's cool about UIDynamicBehavior is it has + +1421 +01:12:14,964 --> 01:12:17,999 +a var called DynamicAnimator, which will get you + +1422 +01:12:18,001 --> 01:12:21,102 +the UIDynamicAnimator that this behavior is in. + +1423 +01:12:21,104 --> 01:12:23,971 +Because remember we add behaviors to dynamic animators + +1424 +01:12:23,973 --> 01:12:25,773 +as like the second slide I showed you. + +1425 +01:12:25,775 --> 01:12:27,342 +So you can find out what it is. And + +1426 +01:12:27,344 --> 01:12:30,311 +in fact it'll even tell you if you move to an animator. + +1427 +01:12:30,313 --> 01:12:33,348 +That's usually you, the animator being taken away from + +1428 +01:12:33,350 --> 01:12:35,316 +you because they wanna stop animation, or + +1429 +01:12:35,318 --> 01:12:37,885 +add it back to you to continue animation, okay? So + +1430 +01:12:37,887 --> 01:12:42,090 +that's a good way to find out that that's happening. Okay, + +1431 +01:12:42,092 --> 01:12:46,561 +UIDynamicBehavior also has a really cool var + +1432 +01:12:46,563 --> 01:12:50,965 +called action which is a closure, okay? + +1433 +01:12:50,967 --> 01:12:54,402 +You can set this closure to anything you want and + +1434 +01:12:54,404 --> 01:12:56,671 +every time this behavior does anything, + +1435 +01:12:56,673 --> 01:13:00,575 +it's gonna call this closure. So some behaviors call this + +1436 +01:13:00,577 --> 01:13:03,811 +thing all the time cuz they're always acting on + +1437 +01:13:03,813 --> 01:13:07,382 +the particular items, okay? So you wawnna be careful to make + +1438 +01:13:07,384 --> 01:13:09,917 +sure whatever's in this closure is really efficient. + +1439 +01:13:09,919 --> 01:13:12,787 +This is one of those cases where you do wanna kinda + +1440 +01:13:12,789 --> 01:13:15,990 +think about optimizing prematurely here because + +1441 +01:13:15,992 --> 01:13:16,824 +this could be called a lot. + +1442 +01:13:16,826 --> 01:13:18,960 +So you don't wanna do anything expensive in here. + +1443 +01:13:18,962 --> 01:13:22,296 +Okay, but it's really kinda cool because you can then + +1444 +01:13:22,298 --> 01:13:25,433 +do things as the animation is happening, finding as things + +1445 +01:13:25,435 --> 01:13:28,970 +are happening in the animation you can be getting involved. + +1446 +01:13:28,972 --> 01:13:31,072 +Okay, so it's really kind of a cool method. + +1447 +01:13:31,074 --> 01:13:32,407 +Now one of the uses we can do for + +1448 +01:13:32,409 --> 01:13:33,875 +this is that push behavior conundrum, + +1449 +01:13:33,877 --> 01:13:37,011 +you got an instantaneous push, it's already pushed. Now you + +1450 +01:13:37,013 --> 01:13:39,147 +wanna remove it. Well this would be a great way to do it. + +1451 +01:13:39,149 --> 01:13:43,017 +Just have an action on that push behavior then set + +1452 +01:13:43,019 --> 01:13:46,220 +the push behavior to remove itself when you're done and + +1453 +01:13:46,222 --> 01:13:49,357 +this is what it would look like. Oops, no, sorry. + +1454 +01:13:49,359 --> 01:13:51,826 +One more thing before I talk about that. This is + +1455 +01:13:51,828 --> 01:13:54,962 +the dynamic animator also has a delegate. And it'll tell + +1456 +01:13:54,964 --> 01:13:59,267 +you when the animator paused or resumed. Now what causes + +1457 +01:13:59,269 --> 01:14:03,137 +the animator to pause? It's when all the objects reach + +1458 +01:14:03,139 --> 01:14:06,707 +stasis. In other words, none of the behaviors are causing + +1459 +01:14:06,709 --> 01:14:09,410 +any of the objects to change, okay? Then it pauses. + +1460 +01:14:09,412 --> 01:14:13,147 +As soon as a push comes in or something like that, + +1461 +01:14:13,149 --> 01:14:16,250 +causes things to start moving again, it will resume. So you + +1462 +01:14:16,252 --> 01:14:20,087 +can find out when things have reached a steady state and + +1463 +01:14:20,089 --> 01:14:23,157 +when they resume, using these delegate methods + +1464 +01:14:23,159 --> 01:14:26,594 +of the dynamic animator, okay? All right, back to that push + +1465 +01:14:26,596 --> 01:14:28,463 +state that I was talking about. All right, so + +1466 +01:14:28,465 --> 01:14:30,631 +here I've created a push behavior with a certain + +1467 +01:14:30,633 --> 01:14:33,267 +magnitude and angle, right? And look what I've got. + +1468 +01:14:33,269 --> 01:14:36,237 +I've set the push behavior's action to be, + +1469 +01:14:36,239 --> 01:14:40,241 +remove this pushBehavaior from the dynamic animator. + +1470 +01:14:40,243 --> 01:14:45,046 +You see that? And since it's instantaneous, + +1471 +01:14:45,048 --> 01:14:47,748 +see how its mode is instantaneous? This is fine. + +1472 +01:14:47,750 --> 01:14:49,817 +I want this thing removed. I don't want it sitting around + +1473 +01:14:49,819 --> 01:14:52,820 +there collecting dust because it's not gonna fire ever + +1474 +01:14:52,822 --> 01:14:56,057 +again. It fired, the action method got called, + +1475 +01:14:56,059 --> 01:14:57,792 +I put this closure method in here to do this. But + +1476 +01:14:57,794 --> 01:15:01,963 +of course this has a memory cycle, a really bad one, okay? + +1477 +01:15:01,965 --> 01:15:06,534 +Because, this push behavior has a var + +1478 +01:15:06,536 --> 01:15:11,105 +action which is a closure. So, it has a strong pointer to + +1479 +01:15:11,107 --> 01:15:13,841 +this closure. Push behavior's action is a strong pointer to + +1480 +01:15:13,843 --> 01:15:17,979 +this closure. And this closure references the pushBehavior, + +1481 +01:15:17,981 --> 01:15:21,282 +so it has a strong pointer back to the pushBehavior. So + +1482 +01:15:21,284 --> 01:15:22,583 +this will happen just fine and + +1483 +01:15:22,585 --> 01:15:25,419 +now the only people pointing to this pushBehavior, + +1484 +01:15:25,421 --> 01:15:28,623 +since it got removed from the dynamicAnimator, the only + +1485 +01:15:28,625 --> 01:15:33,361 +thing pointing to it is this closure. And it's pointing to + +1486 +01:15:33,363 --> 01:15:36,964 +closure, so they're keeping each other in the heap, okay? + +1487 +01:15:36,966 --> 01:15:39,767 +So this is our classic memory cycle. + +1488 +01:15:39,769 --> 01:15:41,669 +And just to remind how we break it here, + +1489 +01:15:41,671 --> 01:15:44,872 +we're just gonna put unowned pushBehavior in here. Cuz we + +1490 +01:15:44,874 --> 01:15:48,476 +know that this can never be out of the heap when action is + +1491 +01:15:48,478 --> 01:15:52,013 +called by definition. Okay, action is only called when his + +1492 +01:15:52,015 --> 01:15:55,216 +pushBehavior does anything. So it has to clearly still be in + +1493 +01:15:55,218 --> 01:15:57,251 +the heap [INAUDIBLE] done anything, okay? + +1494 +01:15:57,253 --> 01:15:59,420 +So we can just put out known pushBehavior, boom, + +1495 +01:15:59,422 --> 01:16:02,924 +breaks our cycle. This will be just a refresher course in + +1496 +01:16:02,926 --> 01:16:08,262 +breaking the recycles. Okay, I made it. Okay, so as before, + +1497 +01:16:08,264 --> 01:16:10,698 +here's what we're doing coming up. If you have any + +1498 +01:16:10,700 --> 01:16:13,801 +questions I will be here as usual. + +1499 +01:16:14,771 --> 01:16:15,036 +>> For more, + +1500 +01:16:15,038 --> 01:16:15,069 +please visit us at stanford.edu + diff --git a/subtitles/14. Animation and Core Motion.srt b/subtitles/14. Animation and Core Motion.srt new file mode 100644 index 0000000..cb91f6b --- /dev/null +++ b/subtitles/14. Animation and Core Motion.srt @@ -0,0 +1,5492 @@ +1 +00:00:00,001 --> 00:00:03,635 +[MUSIC] + +2 +00:00:03,637 --> 00:00:08,774 +Stanford University. >> Okay well welcome + +3 +00:00:08,776 --> 00:00:13,379 +then to Lecture 14 of CS Stanford CS193P, + +4 +00:00:13,381 --> 00:00:18,384 +Spring of 2016. Today, we have two topics. One is, + +5 +00:00:18,386 --> 00:00:21,587 +I'm gonna continue the dynamic animation we talked about in + +6 +00:00:21,589 --> 00:00:24,456 +the last lecture and slides with a big ol' demo. Okay, + +7 +00:00:24,458 --> 00:00:28,660 +that really shows a lot of dynamic, animation in action + +8 +00:00:28,662 --> 00:00:31,897 +and homework Assignment Six is all about dynamic animation, + +9 +00:00:31,899 --> 00:00:34,433 +so be preparing you for that. And then I'm gonna do a new + +10 +00:00:34,435 --> 00:00:37,336 +topic. I had said last time it was probably gonna be Alerts, + +11 +00:00:37,338 --> 00:00:40,172 +but actually I'm gonna do CoreMotion now, okay. + +12 +00:00:40,174 --> 00:00:43,842 +And we'll, I'm gonna redo some slides on CoreMation, + +13 +00:00:43,844 --> 00:00:46,645 +Core Motion, and then I'll also do a demo. Hopefully I'll + +14 +00:00:46,647 --> 00:00:50,849 +have enough time to do all of that today, all right. Okay, + +15 +00:00:50,851 --> 00:00:54,386 +so let's dive right into this demo. It's called Dropit. It's + +16 +00:00:54,388 --> 00:00:57,756 +basically as if I were gonna go write a Tetris app, okay, + +17 +00:00:57,758 --> 00:01:00,259 +with the little falling blocks that you put in place and + +18 +00:01:00,261 --> 00:01:02,761 +then you complete a row and the row would disappear and + +19 +00:01:02,763 --> 00:01:04,730 +then more blocks would come down. Kinda like that, + +20 +00:01:04,732 --> 00:01:06,732 +but this is a demo. We're starting from scratch. + +21 +00:01:06,734 --> 00:01:08,300 +So we're just gonna have little individuals + +22 +00:01:08,302 --> 00:01:11,070 +blocks come down and when they all make a row then it'll + +23 +00:01:11,072 --> 00:01:14,606 +disappear. So we're not gonna do the L-shaped and T-shaped + +24 +00:01:14,608 --> 00:01:17,509 +blocks from Tetris. We're just gonna do squares only. Okay, + +25 +00:01:17,511 --> 00:01:20,279 +so it's kind of like we're getting started on Tetris. + +26 +00:01:20,281 --> 00:01:23,515 +So I'm not calling it Tetris because it doesn't look enough + +27 +00:01:23,517 --> 00:01:23,782 +like Tetris for that. + +28 +00:01:23,784 --> 00:01:25,984 +I'll call it DropIt because we're gonna dropping, + +29 +00:01:25,986 --> 00:01:30,055 +little squares. Okay, so I'm gonna create a new project + +30 +00:01:30,057 --> 00:01:34,426 +here. It's an iOS application as always. Single view.. + +31 +00:01:34,428 --> 00:01:39,531 +I'm gonna call it Dropit. Okay, we don't need core data. + +32 +00:01:39,533 --> 00:01:40,766 +Okay it can be universal app, + +33 +00:01:40,768 --> 00:01:42,267 +I don't see any reason why this app wouldn't be + +34 +00:01:42,269 --> 00:01:45,270 +universal as you'll see. Okay. So here's Dropit, + +35 +00:01:45,272 --> 00:01:48,640 +we'll put it where we always put everything. Here it is. + +36 +00:01:48,642 --> 00:01:51,009 +Now what's interesting about Dropit is I'm gonna build + +37 +00:01:51,011 --> 00:01:55,380 +the entire user interface in code. So my story board all + +38 +00:01:55,382 --> 00:01:58,984 +it's gonna have is one custom view. Okay, and then I'm + +39 +00:01:58,986 --> 00:02:01,587 +gonna do all in code because we're gonna use the animator. + +40 +00:02:01,589 --> 00:02:03,722 +We're gonna have a lot of animated views going on. + +41 +00:02:03,724 --> 00:02:06,992 +That's what's gonna be the entire UI. So,um, + +42 +00:02:06,994 --> 00:02:09,428 +I don't really want this generic ViewController here. + +43 +00:02:09,430 --> 00:02:12,965 +So I'm just gonna take this generic ViewController and + +44 +00:02:12,967 --> 00:02:15,501 +delete it, okay, move it to the trash. And + +45 +00:02:15,503 --> 00:02:18,470 +then I'm going to do the thing we always do here where we + +46 +00:02:18,472 --> 00:02:21,306 +take these little guys and move them off into supporting + +47 +00:02:21,308 --> 00:02:26,111 +files because we don't need to do anything, supporting files, + +48 +00:02:26,113 --> 00:02:28,914 +because we don't really need to do anything with them. And + +49 +00:02:28,916 --> 00:02:32,284 +so I'm gonna right off the bat create a custom ViewController + +50 +00:02:32,286 --> 00:02:36,522 +for this view controller that I have here in my storyboard. + +51 +00:02:36,524 --> 00:02:38,323 +And I'm also gonna create a custom UIView. + +52 +00:02:38,325 --> 00:02:41,360 +And that UIView is really where the logic of my game is, + +53 +00:02:41,362 --> 00:02:43,862 +you can almost think of it as like a gameView. Right, and + +54 +00:02:43,864 --> 00:02:47,099 +I could actually put this view anywhere in any UI and + +55 +00:02:47,101 --> 00:02:47,332 +it would play this game, + +56 +00:02:47,334 --> 00:02:51,436 +the Tetris-like game we gonna call DropIt. So let's go and + +57 +00:02:51,438 --> 00:02:54,973 +create those two classes. The UI view controller and + +58 +00:02:54,975 --> 00:02:59,878 +UI view. So here's to UI view, we'll call it DropItView. + +59 +00:02:59,880 --> 00:03:00,879 +Okay, it's gonna be the DropItView. + +60 +00:03:00,881 --> 00:03:04,650 +I'll put it in the same place here not in supporting files. + +61 +00:03:04,652 --> 00:03:09,188 +I'm gonna put where all the rest of the things are. Hey, + +62 +00:03:09,190 --> 00:03:09,855 +there's my DropItView. + +63 +00:03:09,857 --> 00:03:13,625 +My DropItView actually is not gonna implement DrawRect, + +64 +00:03:13,627 --> 00:03:15,894 +okay, it's gonna implement its entire existence with + +65 +00:03:15,896 --> 00:03:20,098 +subviews. Okay, so it's not even gonna have, a DrawRect in + +66 +00:03:20,100 --> 00:03:24,836 +my DropItView. And then I also need, my controller, okay. + +67 +00:03:24,838 --> 00:03:27,873 +So same thing here. But this is gonna be UIViewController, + +68 +00:03:27,875 --> 00:03:30,909 +and I'm gonna call it my DropItViewController, okay. + +69 +00:03:30,911 --> 00:03:35,147 +Same place. Okay, there's my DropItViewController, + +70 +00:03:35,149 --> 00:03:40,152 +you're gonna clear all this stuff out. All right, now that + +71 +00:03:40,154 --> 00:03:42,754 +I have these two classes, I'm gonna make my storyboard + +72 +00:03:42,756 --> 00:03:46,458 +just make it so that this ViewController that I have, + +73 +00:03:46,460 --> 00:03:49,494 +I'm gonna go to the Identity Inspector over here and + +74 +00:03:49,496 --> 00:03:51,563 +instead of having it be just + +75 +00:03:51,565 --> 00:03:52,097 +plain ViewController, + +76 +00:03:52,099 --> 00:03:54,700 +it's gonna be a DropItViewController. + +77 +00:03:54,702 --> 00:03:58,870 +Okay, and same thing inside here I'm just gonna put a view + +78 +00:03:58,872 --> 00:04:02,441 +a generic UI view, so let's scroll down and find that, + +79 +00:04:02,443 --> 00:04:06,044 +where that is. Where is that? Right here it is. Okay, + +80 +00:04:06,046 --> 00:04:07,746 +generic UI view I'm gonna put in here and + +81 +00:04:07,748 --> 00:04:13,185 +I'm gonna change its identify to be DropItView. Okay. + +82 +00:04:13,187 --> 00:04:16,288 +Now I'm gonna have, use constraints here to have this + +83 +00:04:16,290 --> 00:04:20,025 +fill my entire view controller here. You're gonna put + +84 +00:04:20,027 --> 00:04:22,694 +it right there. Use the blue lines to put it on the edges + +85 +00:04:22,696 --> 00:04:27,399 +then we'll go down to here, oops, down to here, + +86 +00:04:27,401 --> 00:04:29,735 +and we'll say reset to suggested constraints. + +87 +00:04:29,737 --> 00:04:32,304 +I always like to look in the Size Inspector, make sure it + +88 +00:04:32,306 --> 00:04:36,074 +did what I wanted, which it looks like it did. Okay. So + +89 +00:04:36,076 --> 00:04:38,844 +I've got this DropItView in here inside my + +90 +00:04:38,846 --> 00:04:41,880 +DropItViewController. I'm also gonna create an outlet from + +91 +00:04:41,882 --> 00:04:45,050 +one to the other. Okay? Okay, so I'm just gonna control drag + +92 +00:04:45,052 --> 00:04:47,452 +into my DropItViewController to create this view. + +93 +00:04:47,454 --> 00:04:51,323 +I'm gonna call it my gameView. You can see there's of type + +94 +00:04:51,325 --> 00:04:54,393 +DropItView, which is good. It's what I want. Okay, so + +95 +00:04:54,395 --> 00:04:56,795 +I've got my gameView. So this is my basic setup of + +96 +00:04:56,797 --> 00:05:00,132 +my game, all right. And really all the controller's gonna do, + +97 +00:05:00,134 --> 00:05:02,968 +maybe set up some gestures, possibly a little bit + +98 +00:05:02,970 --> 00:05:05,370 +of ViewController life cycle here and there, but most + +99 +00:05:05,372 --> 00:05:10,075 +of the logic is going to be inside this DropItView class. + +100 +00:05:10,077 --> 00:05:16,148 +Okay. So Let's make our screen bigger here. All right. + +101 +00:05:16,150 --> 00:05:19,951 +So let's dive right in to this DropItView. I'm gonna have my + +102 +00:05:19,953 --> 00:05:24,489 +DropItView start by being able to put a little square. Okay, + +103 +00:05:24,491 --> 00:05:27,326 +these things that are gonna fall down like Tetric, Tetris, + +104 +00:05:27,328 --> 00:05:28,260 +except for there's gonna be squares. + +105 +00:05:28,262 --> 00:05:31,063 +I'm gonna have a little method that puts a square there. + +106 +00:05:31,065 --> 00:05:33,899 +Okay so I'm gonna need a little bit of some private + +107 +00:05:33,901 --> 00:05:39,438 +data here. How about Private let dropsPerRow = 10. + +108 +00:05:39,440 --> 00:05:42,941 +So this is how many of these little drops that are gonna + +109 +00:05:42,943 --> 00:05:45,577 +fall down will fit across the top of my view, + +110 +00:05:45,579 --> 00:05:47,846 +they're falling down from the top, right? So + +111 +00:05:47,848 --> 00:05:50,048 +this is how many. So ten across is a good number, + +112 +00:05:50,050 --> 00:05:53,752 +I think. And then I'm gonna have a dropSize, okay, + +113 +00:05:53,754 --> 00:05:56,888 +which is gonna be a CGSize. That's gonna be the size + +114 +00:05:56,890 --> 00:05:58,790 +of each of the little things that falls down. + +115 +00:05:58,792 --> 00:06:01,993 +And I'm gonna have that be calculated. Kay? + +116 +00:06:01,995 --> 00:06:03,628 +And I'm gonna calculate it by having the size, + +117 +00:06:03,630 --> 00:06:07,232 +have it be square. And we'll have the size be the width, + +118 +00:06:07,234 --> 00:06:10,168 +whatever our width is at the time we ask this, + +119 +00:06:10,170 --> 00:06:13,805 +divided by the number of drops per row. Right, so + +120 +00:06:13,807 --> 00:06:17,242 +I'm gonna have the size be so that they'll fit across + +121 +00:06:17,244 --> 00:06:20,011 +the width of our view. Now, by the way, + +122 +00:06:20,013 --> 00:06:22,714 +our app might rotate and this width might change, so + +123 +00:06:22,716 --> 00:06:25,317 +the drops might actually change as we rotate and stuff. + +124 +00:06:25,319 --> 00:06:28,453 +But we can decide if that's what we wanted or not, but + +125 +00:06:28,455 --> 00:06:29,421 +this is perfectly fine. + +126 +00:06:29,423 --> 00:06:32,891 +So, now I'm just gonna create a CG size here whose width + +127 +00:06:32,893 --> 00:06:36,328 +is the size and whose height is the size. So it's square, + +128 +00:06:36,330 --> 00:06:38,230 +basically. So this is gonna be the size of a drop, + +129 +00:06:38,232 --> 00:06:40,232 +a square that fits ten across the top. + +130 +00:06:40,234 --> 00:06:44,035 +Now I'm gonna have a function called addDrop, that just + +131 +00:06:44,037 --> 00:06:47,305 +adds one of these things. One of these little squares that's + +132 +00:06:47,307 --> 00:06:49,975 +gonna fall down from the top to the view. So, of course, + +133 +00:06:49,977 --> 00:06:53,078 +we need the size of this drop, to be put into a frame. + +134 +00:06:53,080 --> 00:06:56,782 +So I'm gonna create a frame which is CGRect. The origin + +135 +00:06:56,784 --> 00:07:00,752 +of the frame is gonna be at CGPoint.zero to start. + +136 +00:07:00,754 --> 00:07:02,287 +I'm gonna put it up in the upper left hand corner and + +137 +00:07:02,289 --> 00:07:05,023 +then I'm gonna move it over into one of the slots along + +138 +00:07:05,025 --> 00:07:08,894 +the top. And the size of course is the dropSize. So + +139 +00:07:08,896 --> 00:07:11,329 +let's do that frame movement. So I am gonna move + +140 +00:07:11,331 --> 00:07:16,435 +the origin.x = and really what I want here is a random + +141 +00:07:16,437 --> 00:07:21,373 +float somewhere between 0 and the drops per row. Okay, + +142 +00:07:21,375 --> 00:07:24,242 +that's pretty much where I am going to put it. + +143 +00:07:24,244 --> 00:07:27,512 +So, if I like to sometimes, if I want to have a function on + +144 +00:07:27,514 --> 00:07:30,816 +CG float called random I'll actually make extensions and + +145 +00:07:30,818 --> 00:07:34,119 +so I've made some extensions, here they are right here, + +146 +00:07:34,121 --> 00:07:38,089 +UIKitExtensions.swift which I'm gonna copy in here. And + +147 +00:07:38,091 --> 00:07:41,493 +these extensions are just kinda some convenient things + +148 +00:07:41,495 --> 00:07:43,929 +that I've created that are gonna help my demo go + +149 +00:07:43,931 --> 00:07:47,098 +quicker. So you can see I have created this random function + +150 +00:07:47,100 --> 00:07:50,302 +on CGFloat. I've created a random function on UIColor + +151 +00:07:50,304 --> 00:07:54,439 +which gives me a random color. Kind of fun, right? + +152 +00:07:54,441 --> 00:07:57,476 +And then some CGRect things here, other stuff, + +153 +00:07:57,478 --> 00:08:01,146 +so you can look through this later at your leisure. + +154 +00:08:01,148 --> 00:08:03,849 +But I'm going to use one of here, + +155 +00:08:03,851 --> 00:08:08,253 +which is this CGFloat.random That takes an int, + +156 +00:08:08,255 --> 00:08:13,325 +dropsPerRow. Okay, and so that's gonna create a random + +157 +00:08:13,327 --> 00:08:16,228 +float between 0 and dropsPerRow, and + +158 +00:08:16,230 --> 00:08:20,599 +then I'm going to multiply that times our dropSize width. + +159 +00:08:20,601 --> 00:08:25,070 +So I've picked a spot across the top a random spot across + +160 +00:08:25,072 --> 00:08:27,539 +the top there. So now, I'm gonna create the drop. + +161 +00:08:27,541 --> 00:08:31,309 +I'm just gonna say it's a UIView a generic UIView + +162 +00:08:31,311 --> 00:08:34,646 +whose frame is frame. Okay, that this frame I just created + +163 +00:08:34,648 --> 00:08:39,117 +right here. So I got the drop. And let's set the drops back + +164 +00:08:39,119 --> 00:08:42,254 +color to a random color equals UIColor, that random. + +165 +00:08:42,256 --> 00:08:44,589 +Yeah, that's one of my UI kit extensions that I created + +166 +00:08:44,591 --> 00:08:48,360 +there And then we're gonna add sub-view, the drop, okay? + +167 +00:08:48,362 --> 00:08:52,330 +Just put it, on screen, okay? Make sense? Now, + +168 +00:08:52,332 --> 00:08:56,835 +I'm gonna cause this add drop to happen whenever I tap, so + +169 +00:08:56,837 --> 00:08:58,870 +I'm gonna put a gesture recognizer back here at my + +170 +00:08:58,872 --> 00:09:01,273 +control. A lot of this, by the way, is review hopefully for + +171 +00:09:01,275 --> 00:09:05,544 +you guys, but I'm going to, when my game view gets set + +172 +00:09:05,546 --> 00:09:08,747 +here I'm gonna add a gesture recognizer. So + +173 +00:09:08,749 --> 00:09:12,551 +I'm just gonna say gameView.addGestureRecognizer. + +174 +00:09:12,553 --> 00:09:15,620 +It's gonna be a tap. UITapGestureRecognizer. + +175 +00:09:15,622 --> 00:09:19,658 +The target: is gonna be my self, + +176 +00:09:19,660 --> 00:09:22,827 +and the action: will be, let's say a #selector. + +177 +00:09:22,829 --> 00:09:25,997 +We'll call it addDrop. This one has an argument. Okay? + +178 +00:09:25,999 --> 00:09:29,434 +Cuz it's a gesture recognizer. Okay, so we'll just do that. + +179 +00:09:29,436 --> 00:09:33,104 +And then, I'm gonna have a little func here. Add drop, + +180 +00:09:33,106 --> 00:09:37,876 +which takes a recognizer which is a UITapGestureRecognizer. + +181 +00:09:37,878 --> 00:09:39,978 +What did I do here that's no good? That's good. + +182 +00:09:39,980 --> 00:09:43,949 +We fix that. All right, so when we have TapGesture + +183 +00:09:43,951 --> 00:09:47,352 +we basically wanna check to see if the recognizer state + +184 +00:09:47,354 --> 00:09:52,390 +has moved to ended if it does then there was a tap. And + +185 +00:09:52,392 --> 00:09:54,059 +now, I'm just gonna tell my game view, + +186 +00:09:54,061 --> 00:09:58,730 +okay go ahead and add one of those drops. Okay everybody + +187 +00:09:58,732 --> 00:10:01,666 +see what I did there? Just create a little tap gesture, + +188 +00:10:01,668 --> 00:10:05,136 +just gonna call this method addDrop over in my drop it + +189 +00:10:05,138 --> 00:10:08,273 +view. So let's switch over to the DropItView it again. + +190 +00:10:08,275 --> 00:10:11,076 +It's gonna call it, cause this add drop to happen right here. + +191 +00:10:11,078 --> 00:10:13,411 +All right, so let's go ahead and run, + +192 +00:10:13,413 --> 00:10:18,116 +we'll run on iPhone 6 here. So now, when we tap, + +193 +00:10:18,118 --> 00:10:24,422 +it should put a random color block along the top. Okay, + +194 +00:10:24,424 --> 00:10:28,293 +so tap, there it is, a green one, purple, okay, excellent. + +195 +00:10:28,295 --> 00:10:28,793 +You see, as I click, + +196 +00:10:28,795 --> 00:10:31,463 +it puts more along the top. Now of course, we want these + +197 +00:10:31,465 --> 00:10:34,366 +things to fall down. Okay, we want them to fall down to + +198 +00:10:34,368 --> 00:10:36,968 +the bottom and we know how to do that with Dynamic Animator. + +199 +00:10:36,970 --> 00:10:39,104 +We're just gonna create a gravity behavior, okay, and + +200 +00:10:39,106 --> 00:10:42,240 +the default gravity behavior is downward gravity at 1,000 + +201 +00:10:42,242 --> 00:10:45,977 +points per second squared. So that's exactly what we want. + +202 +00:10:45,979 --> 00:10:48,913 +So that's all we need to do is create a gravity behavior and + +203 +00:10:48,915 --> 00:10:49,180 +add it to an animator. + +204 +00:10:49,182 --> 00:10:53,518 +So let's do that. Up here, we're gonna create a private + +205 +00:10:53,520 --> 00:10:58,990 +let gravity equal a ui gravity behavior, okay? + +206 +00:10:58,992 --> 00:11:01,760 +And of course, I also need an animator so I'm gonna say + +207 +00:11:01,762 --> 00:11:06,297 +private let animator which is gonna be a ui dynamic + +208 +00:11:06,299 --> 00:11:12,037 +animator. And actually, let's just create one right here. + +209 +00:11:12,039 --> 00:11:14,506 +You and I dynamic animator. And we know that when + +210 +00:11:14,508 --> 00:11:16,875 +we created dynamic animator that's gonna be animating + +211 +00:11:16,877 --> 00:11:20,712 +views. We wanna say what the reference view is. Okay. Which + +212 +00:11:20,714 --> 00:11:25,083 +in this case is, self. Okay. Where Drop it view is a view. + +213 +00:11:25,085 --> 00:11:28,486 +So referring to yourself. Now, we have an error here. + +214 +00:11:28,488 --> 00:11:33,091 +Anyone know what the problem here is? Okay, + +215 +00:11:33,093 --> 00:11:37,328 +what are we doing right here? Initializing, right? + +216 +00:11:37,330 --> 00:11:40,231 +We're initializing. Can we refer to self when we're + +217 +00:11:40,233 --> 00:11:44,669 +initializing? No, because self is not fully initialized yet. + +218 +00:11:44,671 --> 00:11:47,405 +So we can get around this though with our favorite + +219 +00:11:47,407 --> 00:11:51,943 +lazy var. Okay. So now, it's not gonna initialize this + +220 +00:11:51,945 --> 00:11:53,044 +until someone ask for the animator. + +221 +00:11:53,046 --> 00:11:54,879 +And that's not gonna happen until we're finish the slide. + +222 +00:11:54,881 --> 00:12:00,485 +So we're winning, right? Okay. So we got that. Now, I'm gonna + +223 +00:12:00,487 --> 00:12:04,589 +actually make a public var called here called animating, + +224 +00:12:04,591 --> 00:12:07,258 +which is gonna be a boll, and we start it out equal + +225 +00:12:07,260 --> 00:12:11,696 +to false. And this is gonna be basically how we turn on and + +226 +00:12:11,698 --> 00:12:13,465 +off the animating. If you say, animating = true, + +227 +00:12:13,467 --> 00:12:15,934 +then we're gonna have these blocks animating. If you say, + +228 +00:12:15,936 --> 00:12:18,770 +animating = false, they'll stop animating. Okay, so + +229 +00:12:18,772 --> 00:12:22,373 +it's kind of like the on/off switch for our DropItView. So + +230 +00:12:22,375 --> 00:12:25,910 +what are we gonna do here? I'm gonna say if someone sets + +231 +00:12:25,912 --> 00:12:30,982 +this, then if they set it to true, then I'm going + +232 +00:12:30,984 --> 00:12:34,619 +to animate this. Which all I need to do to animate, is + +233 +00:12:34,621 --> 00:12:38,423 +to take the animator and add the behavior of the gravity. + +234 +00:12:38,425 --> 00:12:40,959 +Okay? As soon as you add the behavior + +235 +00:12:40,961 --> 00:12:43,061 +to the animator it's going to start animating it. + +236 +00:12:43,063 --> 00:12:47,465 +Okay? And similarly if they turn animating off, + +237 +00:12:47,467 --> 00:12:50,135 +then I'm just going to do the opposite, I'm going to remove + +238 +00:12:50,137 --> 00:12:55,373 +That gravity behaviour. Okay, and that's going to stop + +239 +00:12:56,176 --> 00:13:01,446 +it animating. Okay, got that? Let's go ahead and set this. + +240 +00:13:01,448 --> 00:13:03,148 +We're going to set this in our controllers. + +241 +00:13:03,150 --> 00:13:05,817 +I'm going to go back to our controller right here, and + +242 +00:13:05,819 --> 00:13:07,819 +let's do this in our view controller live cycle. So + +243 +00:13:07,821 --> 00:13:11,556 +how about in View Did Appear? As soon as View Did Appear + +244 +00:13:11,558 --> 00:13:17,996 +happens, let's go ahead and set this gameView's animating + +245 +00:13:18,465 --> 00:13:21,933 +To true. Okay, so that's gonna start it animating. + +246 +00:13:21,935 --> 00:13:28,439 +And similarly, on viewWillDissapear, We + +247 +00:13:28,441 --> 00:13:31,943 +will turn the animation off. Cuz we really don't want this + +248 +00:13:31,945 --> 00:13:36,114 +thing animating while we're not even on screen. So. It's + +249 +00:13:36,116 --> 00:13:40,685 +a good place to turn it on and off. Everyone understand that? + +250 +00:13:40,687 --> 00:13:42,987 +Okay. If you don't understand anything I'm saying, + +251 +00:13:42,989 --> 00:13:45,824 +feel free to stop me. Okay? All right. So + +252 +00:13:45,826 --> 00:13:48,927 +that turns it on and off. We got this thing going. The only + +253 +00:13:48,929 --> 00:13:52,397 +thing we need to do here is this behavior, currently there + +254 +00:13:52,399 --> 00:13:54,599 +are no items that have been added to this behavior. + +255 +00:13:54,601 --> 00:13:57,268 +So nothing, this gravity is not affecting anything. + +256 +00:13:57,270 --> 00:14:00,572 +So of course, every time we add a br-, a drop down here, + +257 +00:14:00,574 --> 00:14:03,308 +we're gonna want to add it to the behavior, + +258 +00:14:03,310 --> 00:14:06,144 +gravity.addItem this (drop). Okay, and + +259 +00:14:06,146 --> 00:14:10,715 +that makes that gravity start affecting that drop. + +260 +00:14:11,184 --> 00:14:13,685 +We've got all that? So that's, we've seen all the steps now, + +261 +00:14:13,687 --> 00:14:15,353 +dynamic animation of making it work, right? + +262 +00:14:15,355 --> 00:14:18,156 +We created the animator, we created our behavior, we added + +263 +00:14:18,158 --> 00:14:20,425 +the behavior to the animator, and then we added items that + +264 +00:14:20,427 --> 00:14:22,694 +we wanted affected by that behavior to the behavior. + +265 +00:14:22,696 --> 00:14:26,231 +All right, so let's go see this work. + +266 +00:14:33,440 --> 00:14:35,406 +Okay, so here we go, let's run, + +267 +00:14:35,408 --> 00:14:36,307 +let's try tap this user or + +268 +00:14:36,309 --> 00:14:40,111 +tap just just to here, and look they're falling down. + +269 +00:14:40,113 --> 00:14:42,680 +See they all fall and we can click as many as we want and + +270 +00:14:42,682 --> 00:14:46,184 +they all fall. Now the problem with this from a Tetris point + +271 +00:14:46,186 --> 00:14:47,819 +of view is they just fall off the bottom and + +272 +00:14:47,821 --> 00:14:51,789 +we really want them to hit the bottom and stop, right? And + +273 +00:14:51,791 --> 00:14:53,324 +pile up so that they will make rows and + +274 +00:14:53,326 --> 00:14:56,427 +we can clear the rows out. Right? So the next thing we're + +275 +00:14:56,429 --> 00:14:58,396 +going to do is put a boundary and we're going to put + +276 +00:14:58,398 --> 00:15:01,065 +the boundary all the way around this thing. Okay. + +277 +00:15:01,067 --> 00:15:03,801 +It's a real simple way to create a collision boundary + +278 +00:15:03,803 --> 00:15:05,703 +all the way around this reference view right here. + +279 +00:15:05,705 --> 00:15:10,742 +So let's do that. All right? Go back over here. + +280 +00:15:10,744 --> 00:15:13,678 +So do that we need to create another behavior like + +281 +00:15:13,680 --> 00:15:17,749 +the gravity behavior. And this one I'm gonna call my collider + +282 +00:15:17,751 --> 00:15:22,420 +and it's gonna be UICollisionBehavior. Okay? + +283 +00:15:22,422 --> 00:15:25,290 +Now I could just do that. The problem is I need to + +284 +00:15:25,292 --> 00:15:28,092 +configure this, cuz I wanna tell this collision behavior, + +285 +00:15:28,094 --> 00:15:32,230 +make the bounds of the reference view be a boundary. + +286 +00:15:32,232 --> 00:15:34,599 +So I'm gonna create this in kind of a cool way, + +287 +00:15:34,601 --> 00:15:37,035 +hopefully you'll remember that you can do this. + +288 +00:15:37,037 --> 00:15:38,870 +I'm gonna do it with a closure. + +289 +00:15:38,872 --> 00:15:42,473 +I'm gonna initialize this variable by executing + +290 +00:15:42,475 --> 00:15:47,412 +this closure right here, and remember that we can do that. + +291 +00:15:47,414 --> 00:15:49,614 +So I'm going to create a little local variable here. + +292 +00:15:49,616 --> 00:15:51,015 +Happens to be called the same thing but + +293 +00:15:51,017 --> 00:15:54,185 +wouldn't have to be of the same thing as a variable. + +294 +00:15:54,187 --> 00:15:56,554 +This is just a local inside this enclosure. And + +295 +00:15:56,556 --> 00:16:02,060 +I'm gonna set the collider to translateReferenceBoundsIntoB- + +296 +00:16:02,062 --> 00:16:04,262 +oundary = true. And if you do that, + +297 +00:16:04,264 --> 00:16:08,132 +the UICollisionBehavior will automatically have the bounds + +298 +00:16:08,134 --> 00:16:11,035 +of the reference view be a collision boundary. + +299 +00:16:11,037 --> 00:16:14,706 +Then, we'll return the collider here, okay? + +300 +00:16:14,708 --> 00:16:17,041 +Make sense? Now, this collider, + +301 +00:16:17,043 --> 00:16:21,412 +just like the gravity, here, sorry. If you do this when you + +302 +00:16:21,414 --> 00:16:24,916 +make a closure, don't forget that you have to explicitly + +303 +00:16:24,918 --> 00:16:30,888 +type the var here, and that's because it wants to be + +304 +00:16:30,890 --> 00:16:34,225 +able to check to make sure the return value here matches what + +305 +00:16:34,227 --> 00:16:37,729 +you want it to assign to here. Okay, so + +306 +00:16:37,731 --> 00:16:39,197 +just like we added the gravity behavior, + +307 +00:16:39,199 --> 00:16:41,132 +we're gonna have to add the collider as well, so + +308 +00:16:41,134 --> 00:16:45,570 +just like, here's the gravity, we're gonna do collider, and + +309 +00:16:45,572 --> 00:16:47,538 +same thing obviously when we stop animating, + +310 +00:16:47,540 --> 00:16:50,975 +we want to remove the collider. Okay, and also down + +311 +00:16:50,977 --> 00:16:53,845 +here, we want gravity to work on the drops, we also want + +312 +00:16:53,847 --> 00:16:56,848 +the collider to work on the drops. If I didn't do this, + +313 +00:16:56,850 --> 00:17:00,385 +then the drops would still keep falling off the end, + +314 +00:17:00,387 --> 00:17:03,121 +because the collider would not be behaving, + +315 +00:17:03,123 --> 00:17:06,557 +the collider behavior would not apply to them, okay? + +316 +00:17:06,559 --> 00:17:13,564 +Everybody got that? So let's see if that works. All right, + +317 +00:17:13,566 --> 00:17:15,633 +here we go, drop, and, sure enough, look, + +318 +00:17:15,635 --> 00:17:21,039 +they're piling up. And here when, no, we're never gonna + +319 +00:17:21,041 --> 00:17:24,409 +get a completed row there, how are we gonna do that? + +320 +00:17:24,411 --> 00:17:28,546 +All right, well, we obviously need more behaviors here than + +321 +00:17:28,548 --> 00:17:31,349 +we have. And the next behavior we want to do is a behavior + +322 +00:17:31,351 --> 00:17:33,818 +that makes it so that those things don't rotate like that, + +323 +00:17:33,820 --> 00:17:37,021 +okay, they don't tip over and start piling on top of each + +324 +00:17:37,023 --> 00:17:40,258 +other right there. We want them to stay in nice rows, so + +325 +00:17:40,260 --> 00:17:42,560 +we want to turn rotation off. And to do that, + +326 +00:17:42,562 --> 00:17:45,029 +we need a dynamic item behavior, which I talked about + +327 +00:17:45,031 --> 00:17:47,632 +in lecture. But it's starting to get to a point where I've + +328 +00:17:47,634 --> 00:17:50,435 +kinda got a lot of messy code cuz I'm adding behavior, + +329 +00:17:50,437 --> 00:17:51,636 +behavior, behavior, another one. + +330 +00:17:51,638 --> 00:17:54,372 +I'm gonna add, add, add, remove, remove, add item, + +331 +00:17:54,374 --> 00:17:57,075 +add item. So, I'm gonna do the thing I talk about in lecture + +332 +00:17:57,077 --> 00:17:59,811 +where I create a new behavior which is all these other + +333 +00:17:59,813 --> 00:18:04,415 +behaviors combined, like a composite behavior, okay. So + +334 +00:18:04,417 --> 00:18:07,652 +let's go, File > New up here. + +335 +00:18:07,654 --> 00:18:11,923 +Okay, it's a Cocoa Touch Class. This one is a subclass + +336 +00:18:11,925 --> 00:18:16,861 +of UIDynamicBehavior, okay. And I'm gonna call this + +337 +00:18:16,863 --> 00:18:20,264 +the FallingObjectBehavior, okay, cuz that's what it is, + +338 +00:18:20,266 --> 00:18:24,502 +this is a a thing falling down, a FallingObjectBehavior. + +339 +00:18:24,504 --> 00:18:26,671 +Okay, I don't wanna put it in the top level, + +340 +00:18:26,673 --> 00:18:28,573 +drop it here, I wanna put it down here, + +341 +00:18:28,575 --> 00:18:30,007 +where all the rest of my classes are. + +342 +00:18:30,009 --> 00:18:32,510 +I notice some of you sometimes make that mistake in your + +343 +00:18:32,512 --> 00:18:36,247 +homework. Really nice to keep your files together there. + +344 +00:18:36,249 --> 00:18:38,116 +Okay, so here's my FallingObjectBehavior, + +345 +00:18:38,118 --> 00:18:42,253 +it's a UIDynamicBehavior. And I'm just gonna go and copy and + +346 +00:18:42,255 --> 00:18:45,123 +paste those two behaviors I already have, + +347 +00:18:45,125 --> 00:18:49,627 +these two guys right here, out of here, and over into here, + +348 +00:18:49,629 --> 00:18:52,763 +okay. Cuz now, cuz I want this falling object behavior to + +349 +00:18:52,765 --> 00:18:56,701 +have these two behaviors right here. The other thing + +350 +00:18:56,703 --> 00:18:59,036 +we do when we create a DynamicBehavior subclass is, + +351 +00:18:59,038 --> 00:19:02,607 +we're obviously going to have an init. So I'm gonna override + +352 +00:19:02,609 --> 00:19:05,443 +the init that comes with UIDynamicBehavior, + +353 +00:19:05,445 --> 00:19:08,646 +call super.init, okay, because I, I need to that, from + +354 +00:19:08,648 --> 00:19:10,615 +the rules of init. We haven't talked a lot about inits, + +355 +00:19:10,617 --> 00:19:13,918 +by the way. Again, hopefully you haven't needed them too + +356 +00:19:13,920 --> 00:19:17,054 +much in your, your homeworks. And hopefully you understood + +357 +00:19:17,056 --> 00:19:19,924 +what the reading assignment said about inits. But anyway, + +358 +00:19:19,926 --> 00:19:22,059 +you need to call super.init before you can do stuff. + +359 +00:19:22,061 --> 00:19:25,062 +So I'm going to then add a child behavior, + +360 +00:19:25,064 --> 00:19:29,867 +which is gravity, and I'm gonna add a child behavior, + +361 +00:19:29,869 --> 00:19:31,169 +which is the collider. + +362 +00:19:31,171 --> 00:19:33,971 +Okay, so this is how you build these composites. + +363 +00:19:33,973 --> 00:19:37,108 +You add children behavior, okay. Now, + +364 +00:19:37,110 --> 00:19:41,179 +another nice thing to do is to have a func addItem, okay, + +365 +00:19:41,181 --> 00:19:44,815 +which takes an item which would be a UIDynamicItem, + +366 +00:19:44,817 --> 00:19:47,885 +okay? Remember that UIView implements this protocol. + +367 +00:19:47,887 --> 00:19:51,088 +This is a protocol, okay, UIView implements it. + +368 +00:19:51,090 --> 00:19:53,891 +And here, I just want to make sure that I add this item to + +369 +00:19:53,893 --> 00:19:58,863 +all of my sub, my children, basically, behaviors. So + +370 +00:19:58,865 --> 00:20:04,802 +let's do that. And collider. Okay, and similarly, + +371 +00:20:04,804 --> 00:20:07,371 +we probably, we don't need it for this demo, but + +372 +00:20:07,373 --> 00:20:11,709 +to be complete, we probably want a removeItem as well. + +373 +00:20:13,379 --> 00:20:16,681 +Okay, so now, we've created this new behavior that + +374 +00:20:16,683 --> 00:20:19,884 +we can add items to and that this behavior can be added + +375 +00:20:19,886 --> 00:20:23,854 +to an animator to cause this group of behaviors to happen. + +376 +00:20:23,856 --> 00:20:26,657 +So now let's go back to our DropItView, + +377 +00:20:26,659 --> 00:20:30,094 +and instead having these individual behaviors, + +378 +00:20:30,096 --> 00:20:34,932 +let's create a new behavior, we'll call it dropBehavior, + +379 +00:20:34,934 --> 00:20:38,436 +which is a FallingObjectBehavior. + +380 +00:20:38,438 --> 00:20:41,105 +Okay, so this is one behavior encapsulate all those + +381 +00:20:41,107 --> 00:20:46,077 +behaviors. So now we can put that instead of all these + +382 +00:20:46,079 --> 00:20:50,348 +details. Okay, same thing down here. + +383 +00:20:52,218 --> 00:20:55,486 +All right? So see how this code has gotten so + +384 +00:20:55,488 --> 00:20:58,589 +simple now it fits on one page to do this. And + +385 +00:20:58,591 --> 00:21:01,359 +the actual behavior, the dynamic behavior is now + +386 +00:21:01,361 --> 00:21:05,663 +encapsulated over here in this FallingObjectBehavior instead. + +387 +00:21:05,965 --> 00:21:08,032 +All right? Okay, let's run this and + +388 +00:21:08,034 --> 00:21:10,301 +make sure we haven't broken anything by doing that. + +389 +00:21:10,303 --> 00:21:12,103 +Okay, haven't really changed anything, + +390 +00:21:12,105 --> 00:21:14,939 +I've just moved the code for a different encapsulation. + +391 +00:21:14,941 --> 00:21:17,575 +Here it is, we click, hopefully these things will + +392 +00:21:17,577 --> 00:21:21,112 +still hit the bottom, they do, okay? So all is well. Now, + +393 +00:21:21,114 --> 00:21:25,249 +they're still, can be tippy. See there, they're starting to + +394 +00:21:25,251 --> 00:21:26,450 +tip over. No, they're tipping over, okay. + +395 +00:21:26,452 --> 00:21:29,020 +So they're still tipping, so we need to fix the tippiness. + +396 +00:21:29,022 --> 00:21:31,355 +But now we're gonna fix this tippiness here in + +397 +00:21:31,357 --> 00:21:34,792 +our FallingObjectBehavior. And we're gonna do that by adding + +398 +00:21:34,794 --> 00:21:38,296 +another behavior, okay? This is gonna be the itemBehavior. + +399 +00:21:38,298 --> 00:21:41,599 +This is gonna describe how each of these items behaves + +400 +00:21:41,601 --> 00:21:45,870 +when it goes in all the other behaviors. And we do that with + +401 +00:21:45,872 --> 00:21:48,239 +a UIDynamicItemBehavior, okay, and + +402 +00:21:48,241 --> 00:21:52,643 +I'm gonna initialize this in the same way that I did here, + +403 +00:21:52,645 --> 00:21:57,248 +okay, with a closure. So let's let dib, + +404 +00:21:57,250 --> 00:22:03,120 +a dynamic item behavior, equal a UIDynamicItemBehavior. + +405 +00:22:03,122 --> 00:22:07,024 +And now we can set all kinds of things that dib, this dib, + +406 +00:22:07,026 --> 00:22:09,026 +UIDynamicItemBehavior, knows how to do. + +407 +00:22:09,028 --> 00:22:13,564 +For example, allows rotation? No, so now, our block won't + +408 +00:22:13,566 --> 00:22:17,268 +rotate. We could also do stuff like friction and + +409 +00:22:17,270 --> 00:22:21,238 +also elasticity. So I'm gonna do elasticity of 0.75. + +410 +00:22:21,240 --> 00:22:23,407 +Elasticity of 1 is perfect elasticity. + +411 +00:22:23,409 --> 00:22:26,677 +In other words, no energy is lost by the collision. + +412 +00:22:26,679 --> 00:22:26,977 +They bounce off each other. + +413 +00:22:26,979 --> 00:22:30,281 +So 0.75 is a little energy lost. But, you know, so + +414 +00:22:30,283 --> 00:22:33,417 +I'm not sure what the default elasticity is. But it was low, + +415 +00:22:33,419 --> 00:22:34,752 +because those things came down to the bottom, + +416 +00:22:34,754 --> 00:22:38,155 +they didn't bounce much. They kind of just sat there. + +417 +00:22:38,157 --> 00:22:40,691 +So I'll do that. And now let's return dib. + +418 +00:22:40,693 --> 00:22:44,061 +And of course we need to do the same thing here, + +419 +00:22:44,063 --> 00:22:48,933 +add this child behavior or item behavior. And + +420 +00:22:48,935 --> 00:22:53,270 +same thing here, we want to be able to add items to this. And + +421 +00:22:53,272 --> 00:23:01,011 +we want to be able to remove items as well, okay? So + +422 +00:23:01,013 --> 00:23:03,581 +we've just added this behavior now. These things are all + +423 +00:23:03,583 --> 00:23:06,751 +going to have this kind of behavior as they bounce and + +424 +00:23:06,753 --> 00:23:09,453 +are affected by gravity and things like that. And + +425 +00:23:09,455 --> 00:23:12,823 +notice that to add this stuff, we didn't touch DropItView. + +426 +00:23:12,825 --> 00:23:15,559 +DropItView has not changed, okay? We didn't change + +427 +00:23:15,561 --> 00:23:17,361 +anything there. We're only changing this in + +428 +00:23:17,363 --> 00:23:20,498 +this custom behavior that we've built. Okay, so let's go + +429 +00:23:20,500 --> 00:23:24,301 +ahead and run. See what those changes did, what having no + +430 +00:23:24,303 --> 00:23:26,771 +rotation elasticity did. So here it comes like this, so + +431 +00:23:26,773 --> 00:23:29,407 +here we go. Look, they're much bouncier. And + +432 +00:23:29,409 --> 00:23:31,742 +notice how they'll bounce into each other, okay? + +433 +00:23:31,744 --> 00:23:33,978 +They behave like real objects in the real world. + +434 +00:23:33,980 --> 00:23:36,747 +They're bouncing, and they're not rotating, so they're not + +435 +00:23:36,749 --> 00:23:39,016 +tipping over anymore. They're still bouncing up and down, + +436 +00:23:39,018 --> 00:23:41,619 +though, see? When something lands on a row, it causes them + +437 +00:23:41,621 --> 00:23:45,489 +to bounce up a little bit. But now we're on track for Tetris, + +438 +00:23:45,491 --> 00:23:49,527 +because now we're getting completed rows that we can + +439 +00:23:49,529 --> 00:23:51,529 +have them, have the rows remove. + +440 +00:23:51,531 --> 00:23:54,732 +Now, the code for removing, for kind of removing a row, + +441 +00:23:54,734 --> 00:23:57,802 +it's a little tedious for a demo here. I'm really just + +442 +00:23:57,804 --> 00:24:01,005 +gonna go across the row and do what's called a hit test. + +443 +00:24:01,007 --> 00:24:02,940 +In UI view, it has a hit test, which basically I'm + +444 +00:24:02,942 --> 00:24:04,375 +just looking to see if there's a view there. + +445 +00:24:04,377 --> 00:24:07,077 +So I'm gonna go all the way across each row looking to see + +446 +00:24:07,079 --> 00:24:09,547 +if they're view. And if there's a view in every single + +447 +00:24:09,549 --> 00:24:12,149 +spot, then I'm gonna assume that row is complete and + +448 +00:24:12,151 --> 00:24:14,752 +I'm gonna remove all those views. Okay, so + +449 +00:24:14,754 --> 00:24:18,889 +I wrote that code outside, let's go take a look at it. + +450 +00:24:18,891 --> 00:24:22,827 +We'll put it, let's put it right here. Okay, + +451 +00:24:22,829 --> 00:24:24,128 +it's called removeCompletedRow. + +452 +00:24:24,130 --> 00:24:28,232 +It's just this one method right here, okay? + +453 +00:24:28,234 --> 00:24:30,801 +You can see it goes through, it's doing this hit testing, + +454 +00:24:30,803 --> 00:24:33,571 +it's trying to find the drops to remove. If it finds + +455 +00:24:33,573 --> 00:24:36,974 +the whole row, then it goes through each of the drops and + +456 +00:24:36,976 --> 00:24:37,441 +the drops removed, and + +457 +00:24:37,443 --> 00:24:41,378 +look what it does. It removes it from the drop behavior and + +458 +00:24:41,380 --> 00:24:42,413 +then removes it from superview, so + +459 +00:24:42,415 --> 00:24:44,748 +it just takes that drop right out of there. Okay? + +460 +00:24:44,750 --> 00:24:48,652 +So we're literally just throwing it away, okay? Now, + +461 +00:24:48,654 --> 00:24:52,857 +the question is, when do we call remove completed row? + +462 +00:24:53,426 --> 00:24:56,760 +Okay, do we just kind of call it randomly with an NS timer + +463 +00:24:56,762 --> 00:25:00,831 +or something? No, we're gonna call remove completed row + +464 +00:25:00,833 --> 00:25:06,103 +when all the bouncing stops. Okay, when our + +465 +00:25:06,105 --> 00:25:09,807 +dynamic animation engine pauses, then we're gonna try + +466 +00:25:09,809 --> 00:25:12,376 +to remove a row. Cuz if things are still bouncing, you can't + +467 +00:25:12,378 --> 00:25:14,478 +really be removing rows while things are still bouncing. + +468 +00:25:14,480 --> 00:25:15,145 +So when things have settled down, + +469 +00:25:15,147 --> 00:25:18,148 +then we'll try and remove a complete row if we can. + +470 +00:25:18,150 --> 00:25:19,517 +So, if you remember from lecture, + +471 +00:25:19,519 --> 00:25:21,952 +how do we find out the things have stopped? + +472 +00:25:21,954 --> 00:25:25,656 +We use a dynamic animators delegate, the dynamic animator + +473 +00:25:25,658 --> 00:25:27,858 +will tell it's delegate when things have paused. + +474 +00:25:27,860 --> 00:25:30,928 +When things have stasis, okay? So we're gonna have to do + +475 +00:25:30,930 --> 00:25:34,298 +the same trick here that we did with these other ones, and + +476 +00:25:34,300 --> 00:25:37,001 +use a closure Create this because we just have + +477 +00:25:37,003 --> 00:25:39,670 +the delegates of it. So let's go here and + +478 +00:25:39,672 --> 00:25:43,607 +we'll create a little let animator equal this thing. + +479 +00:25:43,609 --> 00:25:48,846 +And we are just going to set the animator's delegate + +480 +00:25:48,848 --> 00:25:51,916 +to self and return animator. + +481 +00:25:53,686 --> 00:25:56,353 +Okay, and we can use self in here because this is lazy. + +482 +00:25:56,355 --> 00:26:00,190 +Okay. Eh, right? You do that but there is as error here. + +483 +00:26:00,192 --> 00:26:03,527 +What's this error? Can't assign the DropItView to + +484 +00:26:03,529 --> 00:26:06,630 +UIDynamicDeleg eh,DynamicAnimatorDelegate so + +485 +00:26:06,632 --> 00:26:09,366 +we need to go here and say we are a UIDynamic. + +486 +00:26:09,368 --> 00:26:13,504 +Animator delegate, okay? Say we implement this + +487 +00:26:13,506 --> 00:26:16,440 +protocol. Now they're all optional so we don't have to + +488 +00:26:16,442 --> 00:26:18,776 +actually implement any, there's no errors here, but + +489 +00:26:18,778 --> 00:26:21,045 +the one we want is that it will pause. + +490 +00:26:21,047 --> 00:26:23,781 +And that we'll just start typing dynamicAnimator, and + +491 +00:26:23,783 --> 00:26:25,182 +you can se it's actually the very first one. + +492 +00:26:25,184 --> 00:26:27,585 +Here's resume and here's pause. So let's go ahead and + +493 +00:26:27,587 --> 00:26:30,120 +do the pause. So this gets called whenever everything + +494 +00:26:30,122 --> 00:26:33,123 +reach stasis and I'm just going to removeCompletedRow. + +495 +00:26:33,125 --> 00:26:36,026 +If there are no completed rows removeCompletedRow does + +496 +00:26:36,028 --> 00:26:37,828 +nothing, it only removes completed rows + +497 +00:26:37,830 --> 00:26:42,333 +if there are some. Okay, so let's try it see if it works. + +498 +00:26:42,335 --> 00:26:47,371 +Could it really be that easy? Yes. All right here we go. + +499 +00:26:47,373 --> 00:26:49,306 +Drops them down here. Okay, we'll let it + +500 +00:26:49,308 --> 00:26:53,811 +reach stasis where there's no completed row. Okay, + +501 +00:26:53,813 --> 00:26:57,448 +nothing removed, okay, let's add a whole bunch more, + +502 +00:26:57,450 --> 00:27:03,253 +bad enough so that something becomes complete here. Okay, + +503 +00:27:03,255 --> 00:27:05,522 +oops, nope, still need one more, + +504 +00:27:05,524 --> 00:27:05,889 +this column right here, so + +505 +00:27:05,891 --> 00:27:08,926 +we'll keep clicking until we get something in that column. + +506 +00:27:09,261 --> 00:27:12,162 +There it is. Okay, here we go. + +507 +00:27:13,666 --> 00:27:18,402 +Cross your fingers. Boom. Now, notice that + +508 +00:27:18,404 --> 00:27:21,839 +when I remove those views, the animator leapt into action + +509 +00:27:21,841 --> 00:27:24,908 +again. Because it noticed, woah, gravity can now work on + +510 +00:27:24,910 --> 00:27:26,944 +these ones that are not blocked by the other ones. + +511 +00:27:26,946 --> 00:27:29,947 +Okay? And same thing here. And this will happen repeatedly. + +512 +00:27:29,949 --> 00:27:34,518 +Yeah, question. >> Yeah, so the last row or so + +513 +00:27:34,520 --> 00:27:37,755 +sometimes the bottom squares are like a little bit + +514 +00:27:37,757 --> 00:27:38,689 +off the ground. >> Mm-hm. + +515 +00:27:38,691 --> 00:27:39,390 +>> What's going on there? + +516 +00:27:39,392 --> 00:27:39,957 +>> Yeah, you see a little + +517 +00:27:39,959 --> 00:27:40,391 +>> Little bit of white in + +518 +00:27:40,393 --> 00:27:45,095 +there. I'm not 100% sure what that is, but I think + +519 +00:27:45,097 --> 00:27:48,866 +it's just an artifact that all this animation stuff happened, + +520 +00:27:48,868 --> 00:27:52,603 +is happening, in CGFloat space, right? + +521 +00:27:52,605 --> 00:27:54,538 +It's not happening on integer boundaries. And so + +522 +00:27:54,540 --> 00:27:57,675 +it might be that these things landing, maybe they're 0.01, + +523 +00:27:57,677 --> 00:28:00,711 +and so the, it's up enough, round enough so + +524 +00:28:00,713 --> 00:28:01,712 +that it shows the one pixel there. + +525 +00:28:01,714 --> 00:28:04,415 +I'm not really 100% sure why it's not exactly on there. + +526 +00:28:04,417 --> 00:28:06,917 +Remember that, you know, the physics you got a lot + +527 +00:28:06,919 --> 00:28:09,086 +of things bouncing here, off of each other. + +528 +00:28:09,088 --> 00:28:10,954 +Different, amounts and stuff like that. + +529 +00:28:10,956 --> 00:28:12,356 +And these things, and when they could rotate, + +530 +00:28:12,358 --> 00:28:14,958 +you saw, they started tipping over even, and nicking into + +531 +00:28:14,960 --> 00:28:17,895 +each other. So this stuff is not all happening on integer + +532 +00:28:17,897 --> 00:28:20,864 +boundaries, I think that's the bottom line on that. + +533 +00:28:20,866 --> 00:28:23,634 +But I'm not 100% certain. All right, so anyway, this + +534 +00:28:23,636 --> 00:28:27,871 +is working great, okay? We got our tetris engine really + +535 +00:28:27,873 --> 00:28:30,774 +ready to go here, if we just made these not be squares. + +536 +00:28:30,776 --> 00:28:35,245 +And I don't have time to make them be actual you know, + +537 +00:28:35,247 --> 00:28:35,713 +L shapes and all that stuff. + +538 +00:28:35,715 --> 00:28:38,515 +But you get the idea. And you understand how this works. + +539 +00:28:38,517 --> 00:28:42,953 +So, I'm going to Let's turn the rotation back on. + +540 +00:28:42,955 --> 00:28:46,423 +I want to show you something fun here. + +541 +00:28:46,425 --> 00:28:51,495 +Let's make the rotation be true again. Run. + +542 +00:28:54,834 --> 00:28:59,269 +Okay, so put it in here. And these things are gonna bounce + +543 +00:28:59,271 --> 00:29:00,537 +off each other. Uhp! No! No!. No! But, let's + +544 +00:29:00,539 --> 00:29:02,840 +see if removeCompletedRow can work here. Because, actually, + +545 +00:29:02,842 --> 00:29:05,843 +some of these rows still might have a in every slot. + +546 +00:29:05,845 --> 00:29:09,513 +Let's see. There we go! Remove that row. So + +547 +00:29:09,515 --> 00:29:16,186 +it doesn't work quite as well, but it can kind of work. + +548 +00:29:16,188 --> 00:29:19,857 +There we go. Okay? All right. + +549 +00:29:19,859 --> 00:29:23,060 +What's next? Next I'm gonna make it so + +550 +00:29:23,062 --> 00:29:26,463 +that just to show you how the collide, collisions work cuz w + +551 +00:29:26,465 --> 00:29:27,698 +only have collisions with the edges. + +552 +00:29:27,700 --> 00:29:31,401 +I'm gonna put a little round thing in the middle, okay? + +553 +00:29:31,403 --> 00:29:34,838 +That this squares are gonna collide against. Just a little + +554 +00:29:34,840 --> 00:29:36,940 +round circles. So the bottom, there's squeezing him down and + +555 +00:29:36,942 --> 00:29:39,710 +boop bounce of a bit. With just a little round boundary, + +556 +00:29:39,712 --> 00:29:42,279 +okay? Cuz you can put, with these, with the collision + +557 +00:29:42,281 --> 00:29:45,883 +behavior you can put any arbitrary Bezier path as a, + +558 +00:29:45,885 --> 00:29:46,617 +as a boundary anywhere. + +559 +00:29:46,619 --> 00:29:47,551 +And when you're doing your breakout game. + +560 +00:29:47,553 --> 00:29:49,486 +You know, you're probably gonna use those boundaries for + +561 +00:29:49,488 --> 00:29:52,923 +the bricks, for example, okay? And maybe for your paddle + +562 +00:29:52,925 --> 00:29:54,424 +even. You'll be moving the boundary constantly, + +563 +00:29:54,426 --> 00:29:56,593 +because the bricks and the paddle, they don't go flying + +564 +00:29:56,595 --> 00:29:58,896 +around when you hit them they disappear or whatever and + +565 +00:29:58,898 --> 00:30:00,998 +the paddle, when you hit it nothing happens to it, + +566 +00:30:01,000 --> 00:30:04,067 +it stays perfectly the same. Okay, so let's go ahead and + +567 +00:30:04,069 --> 00:30:06,069 +do that. We're just going to put a little round circle + +568 +00:30:06,071 --> 00:30:10,374 +here that is a collision. So, to do that I'm going to go + +569 +00:30:10,376 --> 00:30:12,676 +in my Falling Object behavior here. + +570 +00:30:12,678 --> 00:30:13,644 +And I'm going to make this, + +571 +00:30:13,646 --> 00:30:16,547 +unfortunately my collider is private. And I actually like + +572 +00:30:16,549 --> 00:30:19,683 +to keep it private in my little dynamic behavior here. + +573 +00:30:19,685 --> 00:30:21,985 +But I am going to allow people to add a barrier. + +574 +00:30:21,987 --> 00:30:25,756 +So, I'm gonna create a public function addBarrier. And + +575 +00:30:25,758 --> 00:30:29,126 +you can specify any path you want, a UIBezierPath, that you + +576 +00:30:29,128 --> 00:30:32,296 +want to be the barrier. And let's go ahead and you can + +577 +00:30:32,298 --> 00:30:35,866 +name it as well. So, it will let you give it a name. + +578 +00:30:35,868 --> 00:30:39,236 +And that's because when you put these barriers into + +579 +00:30:39,238 --> 00:30:41,238 +the collider, you name them there as well. + +580 +00:30:41,240 --> 00:30:44,141 +That's how you know which Barrier got hit, okay, and + +581 +00:30:44,143 --> 00:30:47,077 +which barrier you're gonna add or remove or change. So those + +582 +00:30:47,079 --> 00:30:51,982 +are all named. And you just do this with a collider, method. + +583 +00:30:51,984 --> 00:30:57,788 +AddBoundaryWithIdentifier. Okay, here it is, and + +584 +00:30:57,790 --> 00:31:00,757 +so the identifier is the name, and the path is the path that + +585 +00:31:00,759 --> 00:31:03,660 +was passed along in here. If someone calls us, by the way, + +586 +00:31:03,662 --> 00:31:08,665 +I'm also going to conveniently remove any old boundary with + +587 +00:31:08,667 --> 00:31:12,769 +that name. Okay? So if you call this repeatedly, + +588 +00:31:12,771 --> 00:31:17,174 +it'll move the barrier around, just for convenience here. + +589 +00:31:17,810 --> 00:31:19,743 +Okay? So this is a nice public function for + +590 +00:31:19,745 --> 00:31:23,113 +adding a barrier. Let's use that in our drop it view to + +591 +00:31:23,115 --> 00:31:28,518 +add a little barrier in the middle. Now, Where do I + +592 +00:31:28,520 --> 00:31:31,455 +want to put the code that adds that little thing? Well, I + +593 +00:31:31,457 --> 00:31:34,224 +don't know where the middle of my bounds are until my bounds + +594 +00:31:34,226 --> 00:31:37,494 +is set, so I certainly have to wait until my bounds are set, + +595 +00:31:37,496 --> 00:31:39,863 +and actually my bounds could change, right? + +596 +00:31:39,865 --> 00:31:42,432 +They could get rotated. Now my middle is in a different + +597 +00:31:42,434 --> 00:31:45,702 +place, and I want the barrier to always be in the middle. So + +598 +00:31:45,704 --> 00:31:46,737 +you'll remember from our last + +599 +00:31:46,739 --> 00:31:50,540 +demo That when a UI views bounds change, + +600 +00:31:50,542 --> 00:31:53,543 +what gets called? Layout subviews. + +601 +00:31:53,545 --> 00:31:55,846 +All right, it doesn't have a view did layout subviews, it + +602 +00:31:55,848 --> 00:31:58,248 +has the actual layout subviews that lays the subviews out. + +603 +00:31:58,250 --> 00:32:00,517 +So that's a good place to put this thing in the middle. + +604 +00:32:00,519 --> 00:32:03,553 +Because layout subviews gonna get called every single time. + +605 +00:32:03,555 --> 00:32:06,490 +The bounds change. So, that's layoutSubviews. + +606 +00:32:06,492 --> 00:32:11,161 +I'm just gonna subclass else. Super.layoutSubviews. And + +607 +00:32:11,163 --> 00:32:14,298 +all I'm gonna do here in layoutSubviews is to + +608 +00:32:14,300 --> 00:32:18,302 +create a round path, so let path equal UIBezierPath. + +609 +00:32:18,304 --> 00:32:22,739 +And there happens to be a BezierPath ovalInRect + +610 +00:32:22,741 --> 00:32:24,975 +thing to create them. And so + +611 +00:32:24,977 --> 00:32:28,712 +let's have this rect be a CGRect whose center, + +612 +00:32:28,714 --> 00:32:32,582 +this is one of my little UI kit extensions is a, + +613 +00:32:32,584 --> 00:32:35,552 +is a CGRect has a center initializer + +614 +00:32:35,554 --> 00:32:39,022 +will be bounds.mid. That's my mid point of my bounds, + +615 +00:32:39,024 --> 00:32:42,159 +that's also a little extension that I did there. And + +616 +00:32:42,161 --> 00:32:45,929 +we'll have the size of it be the dropSize. Okay so + +617 +00:32:45,931 --> 00:32:47,164 +we're gonna put a little round circle, + +618 +00:32:47,166 --> 00:32:50,367 +the same size as a drop right in the middle. So we have that + +619 +00:32:50,369 --> 00:32:53,737 +path. Let's just call on our drop behavior. We'll add + +620 +00:32:53,739 --> 00:32:57,841 +this barrier with this path. We need to give it a name. + +621 +00:32:57,843 --> 00:33:00,043 +So let's be good programmers here and + +622 +00:33:00,045 --> 00:33:03,046 +do private struct pathNames, we'll call it. + +623 +00:33:03,048 --> 00:33:06,883 +Static let this one we'll call our MiddleBarrier and + +624 +00:33:06,885 --> 00:33:11,121 +we can use any string we want here, just has to be unique so + +625 +00:33:11,123 --> 00:33:15,325 +we'll call it MiddleBarrier. Okay, so + +626 +00:33:15,327 --> 00:33:19,930 +this is PathNames.MiddleBarrier. Okay, + +627 +00:33:19,932 --> 00:33:25,202 +so I'm just adding this named barrier here, to my + +628 +00:33:25,204 --> 00:33:30,507 +to my collision behavior in my drop behavior. All right, + +629 +00:33:30,509 --> 00:33:36,980 +so let's go try it, see what this looks like. All right, + +630 +00:33:36,982 --> 00:33:40,751 +we're dropping them here. Whoop! See that? If we drop + +631 +00:33:40,753 --> 00:33:45,022 +one in the middle, right? Aah, give me a middle one. + +632 +00:33:45,024 --> 00:33:47,224 +There one, see? They're hitting off the middle. + +633 +00:33:47,226 --> 00:33:49,593 +Now this is a little hard to see. See, + +634 +00:33:49,595 --> 00:33:51,228 +you see that it's hitting the barrier, but + +635 +00:33:51,230 --> 00:33:53,096 +you can't actually see the barrier. So + +636 +00:33:53,098 --> 00:33:56,099 +how could we draw that barrier there? Well, + +637 +00:33:56,101 --> 00:34:00,070 +we could implement DrawRect, okay? Our own DrawRect and + +638 +00:34:00,072 --> 00:34:03,573 +draw it, okay, just using just stroke, stroking the thing. + +639 +00:34:03,575 --> 00:34:05,675 +But actually, I'm gonna do something kinda fun. And + +640 +00:34:05,677 --> 00:34:09,012 +this is, really I'm doing it this way to show you, always + +641 +00:34:09,014 --> 00:34:12,215 +think object-oriented when you're building an iOS, okay? + +642 +00:34:12,217 --> 00:34:14,985 +What I'm gonna do instead to draw all that little circle, + +643 +00:34:14,987 --> 00:34:17,854 +is I'm gonna create a new UIView okay, + +644 +00:34:17,856 --> 00:34:22,025 +a new UIView subclass. And all this UIView subclass I'm gonna + +645 +00:34:22,027 --> 00:34:26,663 +create does is it knows how to draw a Bezier Path in itself. + +646 +00:34:26,665 --> 00:34:29,800 +It's just a generic Bezier path-drawing view. And + +647 +00:34:29,802 --> 00:34:33,970 +I'm gonna call it what did I call it? NamedBezierPathsView, + +648 +00:34:33,972 --> 00:34:37,507 +okay, cuz that's what it does. It's gonna have + +649 +00:34:37,509 --> 00:34:40,210 +a dictionary of Bezier paths and it just draws them. + +650 +00:34:40,212 --> 00:34:42,979 +It's really generic. It has nothing to do with DropIt. + +651 +00:34:42,981 --> 00:34:45,849 +I could well end up using this in some other app. Okay, and + +652 +00:34:45,851 --> 00:34:49,686 +this is what this Named BezierPathsView is gonna have. + +653 +00:34:49,688 --> 00:34:54,357 +It's gonna have public var called bezierPaths, okay, + +654 +00:34:54,359 --> 00:34:56,660 +which is going to be a dictionary, + +655 +00:34:56,662 --> 00:35:00,931 +which is String as the key, which is an arbitrary name, + +656 +00:35:00,933 --> 00:35:06,369 +and a UIBezierPath as the value, okay? And that's public + +657 +00:35:06,371 --> 00:35:09,272 +and anybody who wants to use this can just add something to + +658 +00:35:09,274 --> 00:35:13,610 +that, and when they do I'm gonna watch didSet and + +659 +00:35:13,612 --> 00:35:17,114 +do setNeedsDisplay, okay? + +660 +00:35:17,116 --> 00:35:19,249 +So if anyone adds a Bezier path to this, + +661 +00:35:19,251 --> 00:35:22,252 +then I'm going to NeedsDisplay and in my drawRect I'm gonna + +662 +00:35:22,254 --> 00:35:25,689 +draw all these Bezier paths that are in this dictionary. + +663 +00:35:25,691 --> 00:35:29,159 +Which is super simple to do, okay? I'm just gonna say for + +664 +00:35:29,161 --> 00:35:32,863 +_, path) because I don't really care what the names of + +665 +00:35:32,865 --> 00:35:35,298 +them are where I'm drawing them. That's + +666 +00:35:35,300 --> 00:35:38,034 +only w, if someone who's using it wants to replace one that's + +667 +00:35:38,036 --> 00:35:41,938 +already there, they can use the same name. In bezierPaths, + +668 +00:35:41,940 --> 00:35:44,608 +so I'm just enumerating my bezierPath keys and + +669 +00:35:44,610 --> 00:35:47,377 +values, and I don't care about the keys. And I'm just gonna + +670 +00:35:47,379 --> 00:35:51,281 +say path.stroke. So here I've created the world's simplest + +671 +00:35:51,283 --> 00:35:54,084 +little class but it's very powerful drawing class, okay, + +672 +00:35:54,086 --> 00:35:57,287 +cuz it, it, it draws arbitrary Bezier paths. Now if I really + +673 +00:35:57,289 --> 00:35:59,589 +were creating this, I'd probably maybe let you + +674 +00:35:59,591 --> 00:36:02,926 +set the line width and color and other kinds of things, but + +675 +00:36:02,928 --> 00:36:05,061 +here we're just gonna do the, the bar, + +676 +00:36:05,063 --> 00:36:09,065 +bare bones of it here. Okay, now how can I use this + +677 +00:36:09,067 --> 00:36:13,270 +in my DropIt? Anyone have an idea how I could really easily + +678 +00:36:13,272 --> 00:36:17,374 +use this UIView to draw that circle in my DropIt? + +679 +00:36:20,512 --> 00:36:26,449 +How's about if we make DropItView inherit from it? + +680 +00:36:27,853 --> 00:36:31,521 +Now all of a sudden, DropItView has a new instance + +681 +00:36:31,523 --> 00:36:35,225 +variable called BezierPaths which it can set to any + +682 +00:36:35,227 --> 00:36:39,896 +BezierPaths it wants and it'll be drawn in itself, okay? + +683 +00:36:39,898 --> 00:36:42,999 +Everyone got that? So let's do that, okay? + +684 +00:36:43,001 --> 00:36:46,503 +When we set this barrier, let's go ahead and + +685 +00:36:46,505 --> 00:36:49,439 +set our own Bezier paths okay? This Bezier path is, + +686 +00:36:49,441 --> 00:36:53,143 +this is the dictionary that we inherited from that class we + +687 +00:36:53,145 --> 00:36:56,980 +just created. And let's call it middle barrier again. + +688 +00:36:56,982 --> 00:37:01,117 +PathNames.MiddleBarrier, okay, we can give any name we want. + +689 +00:37:01,119 --> 00:37:06,456 +And it's equal to that path we just created. Let's go + +690 +00:37:06,458 --> 00:37:14,064 +take a look at this. And sure enough, there it is. Okay, + +691 +00:37:14,066 --> 00:37:17,767 +now it's stroked with line with one black color fine, but + +692 +00:37:17,769 --> 00:37:19,569 +there it is. And we drop things now, + +693 +00:37:19,571 --> 00:37:23,139 +it's easier to see the things banging off of it. + +694 +00:37:24,009 --> 00:37:27,143 +Okay, and this barrier, of course, if we pile up enough + +695 +00:37:27,145 --> 00:37:30,780 +stuff, the things will start piling up around this barrier, + +696 +00:37:30,782 --> 00:37:33,817 +because everything bounces off of this barrier. + +697 +00:37:33,819 --> 00:37:35,885 +It's causes collision. By the way, + +698 +00:37:35,887 --> 00:37:37,721 +if we put something inside that barrier, okay, + +699 +00:37:37,723 --> 00:37:42,993 +it would bounce around in the inside of the barrier. Okay, + +700 +00:37:42,995 --> 00:37:46,363 +you got that? No remove completed? + +701 +00:37:46,365 --> 00:37:49,766 +Ruh, okay, there we go. There we go. + +702 +00:37:49,768 --> 00:37:52,535 +All right, so that's showing you a little bit there. + +703 +00:37:52,537 --> 00:37:56,640 +Okay the next one I'm gonna do is an attachment behavior. So + +704 +00:37:56,642 --> 00:38:00,677 +I'm gonna allow myself, when a thing drops here, + +705 +00:38:00,679 --> 00:38:03,747 +to grab onto a drop, okay, with my mouse, + +706 +00:38:03,749 --> 00:38:07,317 +or with my finger, if it was on a device and I'd make + +707 +00:38:07,319 --> 00:38:09,886 +an attachment to it. And remember an attachment is like + +708 +00:38:09,888 --> 00:38:13,990 +an iron bar that hooks up from either a point to an item or + +709 +00:38:13,992 --> 00:38:16,092 +between two items. In this case it's gonna be a point, + +710 +00:38:16,094 --> 00:38:19,796 +to point my finger is. And what also cool is, as my, I'm + +711 +00:38:19,798 --> 00:38:22,632 +gonna do a pan gesture and, as my finger moves around, + +712 +00:38:22,634 --> 00:38:24,934 +I'm gonna keep moving that attachment point. And + +713 +00:38:24,936 --> 00:38:28,638 +that bar is gonna be dragged around with it and + +714 +00:38:28,640 --> 00:38:30,507 +the item too, okay? + +715 +00:38:30,509 --> 00:38:33,343 +So that's what we're gonna do. Let's do that attachment + +716 +00:38:33,345 --> 00:38:36,179 +behavior. So, to do the attachment behavior, + +717 +00:38:36,181 --> 00:38:38,748 +I certainly need an attachment behavior. + +718 +00:38:38,750 --> 00:38:43,453 +So I'm gonna create a private var, which is attachment, + +719 +00:38:43,455 --> 00:38:47,624 +UIAttachmentBehavior, okay? Actually we'll have it be + +720 +00:38:47,626 --> 00:38:50,827 +an optional, because we might not have an attachment yet. We + +721 +00:38:50,829 --> 00:38:54,698 +don't have an attachment until we put our finger down on it, + +722 +00:38:54,700 --> 00:39:00,103 +to grab onto it. And when this attachment behavior + +723 +00:39:00,105 --> 00:39:04,674 +gets set to something we need to obviously add + +724 +00:39:04,676 --> 00:39:08,678 +the behavior to our animator, otherwise this attachment + +725 +00:39:08,680 --> 00:39:12,382 +won't do anything, okay? So what do we need to do that? + +726 +00:39:12,384 --> 00:39:16,319 +I'm just going to say if this attachment is not nil, okay, + +727 +00:39:16,321 --> 00:39:19,222 +if someone has set the attachment to be something + +728 +00:39:19,224 --> 00:39:24,728 +other than nil, then animator, addBehavior this attachment. + +729 +00:39:25,464 --> 00:39:27,230 +Okay, everyone understand that? Now, one thing, + +730 +00:39:27,232 --> 00:39:30,500 +by the way, I also am gonna do something we haven't done in + +731 +00:39:30,502 --> 00:39:34,437 +a demo, which is willSet. And willSet happens before the new + +732 +00:39:34,439 --> 00:39:36,973 +value gets set. And what do I wanna do here? + +733 +00:39:36,975 --> 00:39:40,143 +Here I wanna say if my current attachment, + +734 +00:39:40,145 --> 00:39:46,116 +before I've set it, is not nil, then I want to remove it. + +735 +00:39:48,787 --> 00:39:50,186 +Okay, you see why I'm doing this? + +736 +00:39:50,188 --> 00:39:52,789 +Right, if someone sets the attachment to something new, + +737 +00:39:52,791 --> 00:39:55,625 +if there was an old attachment I wanna remove it, okay? So, + +738 +00:39:55,627 --> 00:39:58,828 +here I'm just making sure that every time I set attachment, + +739 +00:39:58,830 --> 00:40:00,997 +the old one gets removed, a new one gets added. + +740 +00:40:00,999 --> 00:40:04,701 +All right with that. Okay, so we've got this attachment,how + +741 +00:40:04,703 --> 00:40:05,969 +are we gonna set this attachment? + +742 +00:40:05,971 --> 00:40:09,706 +We gonna set it to something. I am only gonna allow you to + +743 +00:40:09,708 --> 00:40:12,442 +grab onto the last drop that was dropped. + +744 +00:40:12,444 --> 00:40:15,278 +This cause that you can drop a lot of drops,only the last one + +745 +00:40:15,280 --> 00:40:18,681 +you dropped can you drag grab onto with this pan gesture. + +746 +00:40:18,683 --> 00:40:21,151 +So I'm gonna need a var for the last drop. + +747 +00:40:21,153 --> 00:40:23,853 +So let's go ahead and put a var, I don't know, + +748 +00:40:23,855 --> 00:40:29,692 +we'll put it down here. private var lastDrop, okay, + +749 +00:40:30,061 --> 00:40:33,930 +which is a UIView, okay, and it also could be null, + +750 +00:40:33,932 --> 00:40:35,465 +it might not have dropped anything. And + +751 +00:40:35,467 --> 00:40:39,869 +every time we add a drop, I'm just gonna set the lastDrop + +752 +00:40:39,871 --> 00:40:44,207 +equal to the drop. [INAUDIBLE] understand there, that's just + +753 +00:40:44,209 --> 00:40:47,143 +grabbing the last drop. So, now, I have the last drop, + +754 +00:40:47,145 --> 00:40:51,848 +okay? And I get my finger down, I need to grab onto it, + +755 +00:40:51,850 --> 00:40:52,949 +okay? And create this attachment behavior. + +756 +00:40:52,951 --> 00:40:56,252 +So, how am I gonna do that? All right, let's go here and + +757 +00:40:56,254 --> 00:41:00,557 +create a function called grabDrop which is going to be + +758 +00:41:00,559 --> 00:41:05,795 +a hand gesture Handler, okay. Cuz we're gonna have a pan + +759 +00:41:05,797 --> 00:41:10,967 +gesture be how we grab onto this following drop. Okay, + +760 +00:41:10,969 --> 00:41:13,937 +so first I'm just gonna get the point of the gesture, or + +761 +00:41:13,939 --> 00:41:19,042 +gesturePoint, that's the recognizer locationInView, or + +762 +00:41:19,044 --> 00:41:22,679 +self. Okay, so now we know where that hand gesture is, + +763 +00:41:22,681 --> 00:41:25,415 +either at the start or as we're moving around we know + +764 +00:41:25,417 --> 00:41:28,418 +where it is. So now let's handle these pan + +765 +00:41:28,420 --> 00:41:32,388 +gesture states, okay, recognizer.state. + +766 +00:41:32,390 --> 00:41:36,593 +If it's Began, right, if this thing just began, + +767 +00:41:36,595 --> 00:41:41,197 +then we need to, you know, create the attachment. Okay, + +768 +00:41:41,199 --> 00:41:44,767 +if it's C=changed, okay, person moved the attachment + +769 +00:41:44,769 --> 00:41:49,205 +around, now we need to change the attachments Anchor point. + +770 +00:41:49,207 --> 00:41:51,708 +Okay, cuz remember I said the attachment is gonna attach + +771 +00:41:51,710 --> 00:41:55,645 +a point to that drop and so as we pan around. We're gonna + +772 +00:41:55,647 --> 00:41:58,214 +keep moving the point that it's attached to and that's + +773 +00:41:58,216 --> 00:42:02,051 +gonna drag the trop around with it by the iron bar, okay, + +774 +00:42:02,053 --> 00:42:06,489 +by the stiff bar. Otherwise, I'm just gonna set + +775 +00:42:06,491 --> 00:42:11,327 +the attachment to nil. Okay, because if it's not begin or + +776 +00:42:11,329 --> 00:42:13,263 +change, then it's either ended or some failure, + +777 +00:42:13,265 --> 00:42:16,232 +something like that, I want this attachment to go away. + +778 +00:42:16,234 --> 00:42:16,933 +Okay. If there is an attachment, + +779 +00:42:16,935 --> 00:42:18,801 +I want it to go away so that's the end of the line. + +780 +00:42:18,803 --> 00:42:24,440 +All right. This one's easy, okay. Create the attachment's + +781 +00:42:24,442 --> 00:42:28,211 +anchor point. That's super easy. That's just attachments. + +782 +00:42:28,213 --> 00:42:32,849 +If we have one. AnchorPoint = gesturePoint, okay? + +783 +00:42:32,851 --> 00:42:36,452 +That's it. Okay? Remember, the attachment is just a behavior, + +784 +00:42:36,454 --> 00:42:38,388 +it's an object. It's got a var on it, + +785 +00:42:38,390 --> 00:42:41,524 +which is the anchor point. If it's a point to, + +786 +00:42:41,526 --> 00:42:43,993 +a point connection to a item, it's got an anchor point. + +787 +00:42:43,995 --> 00:42:45,795 +And then we're just gonna change, as you drag around + +788 +00:42:45,797 --> 00:42:47,730 +with the pan, we're just gonna keep changing that. And + +789 +00:42:47,732 --> 00:42:49,933 +the animation system's automatically gonna react to + +790 +00:42:49,935 --> 00:42:50,833 +that. We don't have to do anything. + +791 +00:42:50,835 --> 00:42:53,636 +Just automatically it's going to notice that change and + +792 +00:42:53,638 --> 00:42:57,507 +deal with it. How about creating the attachment? Well, + +793 +00:42:57,509 --> 00:43:01,044 +here we better make sure we have a drop to attach to. + +794 +00:43:01,046 --> 00:43:05,915 +So I'm gonna say if the drop to drop To + +795 +00:43:05,917 --> 00:43:09,886 +attachTo equals the lastDrop. Okay, so in other words, + +796 +00:43:09,888 --> 00:43:12,822 +if we have a lastDrop, cuz we might've just started and + +797 +00:43:12,824 --> 00:43:14,290 +obviously if we start panning when + +798 +00:43:14,292 --> 00:43:16,492 +there's nothing dropping, we can't do it. And + +799 +00:43:16,494 --> 00:43:22,999 +also wanna make sure that that dropToAttachTo is in the view + +800 +00:43:23,001 --> 00:43:29,205 +hierarchy. Okay? So I want to make sure it hasn't + +801 +00:43:29,207 --> 00:43:33,242 +been removed from super view by, remove completed row or + +802 +00:43:33,244 --> 00:43:37,013 +any other way. So if I got a draft drop, I'm just gonna + +803 +00:43:37,015 --> 00:43:42,285 +create an attachment by saying it equals a UI attachment. + +804 +00:43:44,155 --> 00:43:46,856 +Attachment behavior Oops, + +805 +00:43:46,858 --> 00:43:51,594 +we forget attach. Attachment, + +806 +00:43:51,596 --> 00:43:53,896 +UIAttachmentBehavior. And you can see, + +807 +00:43:53,898 --> 00:43:56,332 +here's the different kinds of attachments you can create, + +808 +00:43:56,334 --> 00:43:59,736 +attach to an anchor, an item attached to another item. + +809 +00:43:59,738 --> 00:44:01,671 +You can even attach items to anchors or + +810 +00:44:01,673 --> 00:44:03,606 +other items offsetFromCenter. In other words, + +811 +00:44:03,608 --> 00:44:05,875 +the attachment doesn't have to be in the center of the thing, + +812 +00:44:05,877 --> 00:44:08,645 +it could be on a corner. If you do that Then as you pull + +813 +00:44:08,647 --> 00:44:10,880 +it around that thing's gonna be spinning around because, + +814 +00:44:10,882 --> 00:44:12,849 +you know if you have the corner of a rectangle and you + +815 +00:44:12,851 --> 00:44:16,185 +pull on it its gonna rotate as long as you allow rotation. + +816 +00:44:16,187 --> 00:44:18,755 +Okay? But here I want attached to anchor obviously. I'm + +817 +00:44:18,757 --> 00:44:21,724 +gonna attach it to the anchor which is the pan. The item + +818 +00:44:21,726 --> 00:44:27,730 +is the droptoattachto and the anchor is the gesturePoint. + +819 +00:44:27,732 --> 00:44:30,667 +Okay where the pan gesture went on. + +820 +00:44:30,669 --> 00:44:33,836 +By the way I'm gonna make my game so that once you drab, + +821 +00:44:33,838 --> 00:44:36,706 +grab onto this thing, you can't grab onto it again. + +822 +00:44:36,708 --> 00:44:38,074 +If you grab on and you let it go, + +823 +00:44:38,076 --> 00:44:41,644 +you can't grab it again. So last drop to nil in the case + +824 +00:44:41,646 --> 00:44:46,482 +where I create an attachment. Okay? We have to obviously + +825 +00:44:46,484 --> 00:44:50,286 +add the GestureRecognizer that call this handler, so + +826 +00:44:50,288 --> 00:44:53,256 +we were gonna do that obviously in our controller. + +827 +00:44:53,258 --> 00:44:55,892 +Okay, just like we added this TapGesture, let's go + +828 +00:44:55,894 --> 00:45:01,731 +gameView.addGestureRecognizer, UIPanGesture this time. + +829 +00:45:01,733 --> 00:45:04,634 +The target this time is the gameView. + +830 +00:45:04,636 --> 00:45:11,607 +Okay, and the action is a selector which is + +831 +00:45:11,609 --> 00:45:18,881 +the DropItView.grabDrop with an argument. + +832 +00:45:18,883 --> 00:45:23,986 +Okay, everybody got that? All right, we'll go back here so + +833 +00:45:23,988 --> 00:45:26,422 +you can see this code on the screen at the same time. + +834 +00:45:26,424 --> 00:45:32,695 +To run that. All right, so here we drop it. + +835 +00:45:32,697 --> 00:45:34,997 +I didn't grab it. Okay. We're gonna drop another one. + +836 +00:45:34,999 --> 00:45:38,768 +I grabbed it. Okay, do you see what's happening? It's kind of + +837 +00:45:38,770 --> 00:45:42,004 +hard to see. Watch this. Boing! Okay? So this thing is + +838 +00:45:42,006 --> 00:45:46,776 +bouncing around. I'm dragging it around, ok, with my finger. + +839 +00:45:46,778 --> 00:45:49,579 +Look. I can even it bounce it on the iron bar. + +840 +00:45:49,581 --> 00:45:51,881 +Wooo. Now, it's kind of hard to see this. + +841 +00:45:51,883 --> 00:45:55,852 +Wouldn't it be cool if we could draw a line there? + +842 +00:45:55,854 --> 00:45:58,755 +Okay? So that we could see this iron bar, + +843 +00:45:58,757 --> 00:46:01,724 +that this attachment behavior is creating. And, of course, + +844 +00:46:01,726 --> 00:46:04,660 +we can do that because we inherit from a class that + +845 +00:46:04,662 --> 00:46:07,196 +knows how to draw arbitrary path. So + +846 +00:46:07,198 --> 00:46:09,766 +just like we drew this little one, let's draw that bar. + +847 +00:46:09,768 --> 00:46:13,269 +But it's a little tricky cuz that bar is always changing as + +848 +00:46:13,271 --> 00:46:16,205 +I drag it around with the pen, right? That think is always + +849 +00:46:16,207 --> 00:46:19,542 +changing. So how are we going to have a hook + +850 +00:46:19,544 --> 00:46:22,578 +to know when to draw it? This is where that really cool + +851 +00:46:22,580 --> 00:46:28,050 +UI dynamic behavior mechanism I was talking about is action. + +852 +00:46:28,052 --> 00:46:30,553 +All right. Action is a closure that you can set. + +853 +00:46:30,555 --> 00:46:34,323 +It could get called every time that behavior acts. Perfect. + +854 +00:46:34,325 --> 00:46:37,960 +So I'm gonna put that behavior on that attachment, so that + +855 +00:46:37,962 --> 00:46:41,664 +every time that attachment has any affect on something, + +856 +00:46:41,666 --> 00:46:44,066 +I'm gonna re-draw my line. + +857 +00:46:44,068 --> 00:46:47,136 +Okay. Perfect opportunity to do that. All right. So + +858 +00:46:47,138 --> 00:46:52,108 +I'm gonna do that. Where is a good place to put that? + +859 +00:46:52,110 --> 00:46:59,248 +Let's put it down in where we create the attachment I guess. + +860 +00:46:59,250 --> 00:47:00,183 +Or is that here it is. + +861 +00:47:00,185 --> 00:47:02,285 +Here is where we create the attachment. + +862 +00:47:02,287 --> 00:47:04,387 +This is where we are adding the behavior. + +863 +00:47:04,389 --> 00:47:07,323 +So I'm als, in addition to adding the behavior here, I'm + +864 +00:47:07,325 --> 00:47:12,328 +going to say the attachments. Attachment, I have trouble + +865 +00:47:12,330 --> 00:47:16,833 +typing that. The attachment to action equals some closure. + +866 +00:47:16,835 --> 00:47:21,270 +So in here this is where we wanna draw that line, okay. So + +867 +00:47:21,272 --> 00:47:23,506 +how are we gonna draw this line in here? + +868 +00:47:23,508 --> 00:47:26,409 +How about let's get the attach drop. Okay? + +869 +00:47:26,411 --> 00:47:29,779 +Cuz I wanna draw a line between the point, okay, + +870 +00:47:29,781 --> 00:47:33,482 +that the gestures out and where the attached drop is. + +871 +00:47:33,484 --> 00:47:35,518 +So I need to find that attached drop. So + +872 +00:47:35,520 --> 00:47:38,354 +how can I find the attached drop from the attachment. + +873 +00:47:38,356 --> 00:47:42,191 +Well, here' how we do that. We can get the attachments. Oops, + +874 +00:47:42,193 --> 00:47:47,697 +equals. Get the attach, attachments items. + +875 +00:47:47,699 --> 00:47:49,999 +Okay, that's all the items that it's attaching. + +876 +00:47:50,001 --> 00:47:52,835 +Now it's only gonna be having this one drop attached, + +877 +00:47:52,837 --> 00:47:55,905 +okay it only attaches one drop. But, so this is an array + +878 +00:47:55,907 --> 00:47:59,108 +of items, so I'm gonna get the first one out of there cuz + +879 +00:47:59,110 --> 00:48:02,378 +I know there's only gonna be one. So I've got this first + +880 +00:48:02,380 --> 00:48:05,281 +thing, and I'm gonna make sure it's a UIView, okay? + +881 +00:48:05,283 --> 00:48:08,651 +I just wanna be 100% sure it's a UIView, and I want this var + +882 +00:48:08,653 --> 00:48:11,754 +right here to be of type UIView. Here it's complaining + +883 +00:48:11,756 --> 00:48:14,390 +because this is a closure, and so we have to have self, + +884 +00:48:14,392 --> 00:48:16,092 +explicit self, cuz we're capturing self, + +885 +00:48:16,094 --> 00:48:18,828 +which is actually gonna be a huge problem here, by the way, + +886 +00:48:18,830 --> 00:48:21,330 +to capture self, we'll talk about that in a second, + +887 +00:48:21,332 --> 00:48:24,267 +all right? So now I've got the attached drop, + +888 +00:48:24,269 --> 00:48:30,907 +I just need to create a Bézier path, okay, UIBezierPath. + +889 +00:48:32,377 --> 00:48:36,812 +And I've got a nice lineFrom. Okay, + +890 +00:48:36,814 --> 00:48:42,184 +a UIBezierPath.lineFrom the attachment's anchor point. + +891 +00:48:42,186 --> 00:48:45,121 +Oops, not replacement, + +892 +00:48:45,123 --> 00:48:51,761 +anchorPoint to the attachedDrop.center. + +893 +00:48:52,797 --> 00:48:56,299 +Okay? See what I'm doing there? Okay, we also need some + +894 +00:48:56,301 --> 00:49:00,236 +self dot going on in here. We can do that, + +895 +00:49:00,238 --> 00:49:05,174 +cuz we know we're good on the attachment. What else do + +896 +00:49:05,176 --> 00:49:09,478 +we got here okay, and so we need to give this a name, + +897 +00:49:09,480 --> 00:49:11,247 +right, cuz bezierPath is a dictionary, so + +898 +00:49:11,249 --> 00:49:13,215 +we need give it a name. So let's go back down here and + +899 +00:49:13,217 --> 00:49:16,252 +create another named path, this one we'll call + +900 +00:49:16,254 --> 00:49:21,324 +Attachment. All right, so this is gonna be our + +901 +00:49:21,326 --> 00:49:25,795 +bezierPath[PathNames.Attachme- nt]. Maybe for + +902 +00:49:25,797 --> 00:49:28,631 +readability here, I'll put this on the next line. + +903 +00:49:28,633 --> 00:49:31,467 +Okay? So there, we've created the Bezier path + +904 +00:49:31,469 --> 00:49:35,438 +to show this attachment. Everybody cool with that? Now, + +905 +00:49:35,440 --> 00:49:37,306 +the other thing is, when we remove it, + +906 +00:49:37,308 --> 00:49:39,275 +we better remove that thing. So self dot, + +907 +00:49:39,277 --> 00:49:42,345 +we don't even need self here. We're not inside a closure. + +908 +00:49:42,347 --> 00:49:47,850 +BezierPaths[PathNames.Attachm- ent] = nil. + +909 +00:49:47,852 --> 00:49:51,153 +That's a way to remove something from a dictionary, + +910 +00:49:51,155 --> 00:49:52,989 +by the way, just set it to nil. Okay, + +911 +00:49:52,991 --> 00:49:57,593 +pretty cool with that? Now, as I mentioned we have a serious + +912 +00:49:57,595 --> 00:50:02,732 +problem here with self being captured. Okay, because this + +913 +00:50:02,734 --> 00:50:06,435 +cell, okay, this closure keeps self in the heap. And + +914 +00:50:06,437 --> 00:50:08,204 +self keeps the closure in the heap, + +915 +00:50:08,206 --> 00:50:12,108 +because self.attachment.action equals this closure. So + +916 +00:50:12,110 --> 00:50:13,676 +they each have strong pointers to each other, + +917 +00:50:13,678 --> 00:50:17,313 +they can never leave the heap. Now, this one we can fix with + +918 +00:50:17,315 --> 00:50:21,951 +unowned self. Because we know that this behavior + +919 +00:50:21,953 --> 00:50:26,022 +is gonna leave the heap as soon as self leaves the heap, + +920 +00:50:26,024 --> 00:50:29,759 +so it's perfectly safe here to say, unowned self to + +921 +00:50:29,761 --> 00:50:33,696 +break that loop. Okay, self will never be around when this + +922 +00:50:33,698 --> 00:50:39,068 +attachment behavior's around, still around. Okay, so + +923 +00:50:39,070 --> 00:50:44,340 +let's see if that works. All right, + +924 +00:50:44,342 --> 00:50:47,376 +let's drop a few down. Now I'm gonna grab the next one. + +925 +00:50:47,378 --> 00:50:48,677 +There it is. Okay, so + +926 +00:50:48,679 --> 00:50:52,281 +now we can see a lot better what we're doing here. So + +927 +00:50:52,283 --> 00:50:58,554 +we balance it. Okay? Got it. Make sense? + +928 +00:50:59,390 --> 00:51:03,659 +All right, so that is all I wanted to show you for + +929 +00:51:03,661 --> 00:51:06,529 +behaviors. Any questions about that stuff? I showed you + +930 +00:51:06,531 --> 00:51:08,564 +a lot of behaviors there, attachments, colliders, + +931 +00:51:08,566 --> 00:51:12,601 +item behaviors, gravity, okay, so that's plenty of stuff to + +932 +00:51:12,603 --> 00:51:17,106 +help you get started on your homework there. All right, + +933 +00:51:17,108 --> 00:51:20,676 +let's go back and look at some slides here. So + +934 +00:51:20,678 --> 00:51:24,480 +now I'm gonna talk about Core Motion, okay? Core Motion + +935 +00:51:24,482 --> 00:51:27,917 +is an object-oriented API to get at the motion + +936 +00:51:27,919 --> 00:51:29,285 +sensing hardware on your device. + +937 +00:51:29,287 --> 00:51:32,221 +So that's accelerometer, the gyro, magnetometer, + +938 +00:51:32,223 --> 00:51:36,025 +those kinds of things, all right? Not all devices have + +939 +00:51:36,027 --> 00:51:40,262 +all of this hardware, although in recent years they all do. + +940 +00:51:40,264 --> 00:51:43,499 +But if your app wants to run back on iPhone 4 or + +941 +00:51:43,501 --> 00:51:46,202 +something like that, it doesn't have a gyro, for + +942 +00:51:46,204 --> 00:51:49,839 +example, we kind of, for good programming technique, + +943 +00:51:49,841 --> 00:51:52,741 +wanna check to make sure that we have the hardware, and + +944 +00:51:52,743 --> 00:51:56,946 +you'll see that in a second. You get at all this stuff + +945 +00:51:56,948 --> 00:51:59,682 +via an instance of CMMotionManager. + +946 +00:51:59,684 --> 00:52:03,719 +Now, you really only wanna have one CMMotionManager in + +947 +00:52:03,721 --> 00:52:04,253 +your entire app, + +948 +00:52:04,255 --> 00:52:06,789 +because there's only one gyro in your entire + +949 +00:52:06,791 --> 00:52:09,792 +device, right? So it really makes no sense to have two + +950 +00:52:09,794 --> 00:52:12,228 +motion managers trying to, you know, cross over each + +951 +00:52:12,230 --> 00:52:14,930 +other. You need to coordinate it, so if you really had two + +952 +00:52:14,932 --> 00:52:18,300 +different places in your app where you were accessing + +953 +00:52:18,302 --> 00:52:21,871 +this hardware, then you would need to have a shared motion + +954 +00:52:21,873 --> 00:52:24,440 +manager either as a static on some class + +955 +00:52:24,442 --> 00:52:26,942 +somewhere or maybe part of your app delegate or something + +956 +00:52:26,944 --> 00:52:29,712 +like that, that is, you know, dealing with the fact that two + +957 +00:52:29,714 --> 00:52:33,315 +different people wanna look at the the hardware the same + +958 +00:52:33,317 --> 00:52:34,416 +time, okay? + +959 +00:52:34,418 --> 00:52:36,285 +So how do you use this motion manager to get this + +960 +00:52:36,287 --> 00:52:40,556 +information? Well, first it was two ways really, okay. One + +961 +00:52:40,558 --> 00:52:44,326 +way is by polling, and one way is by getting constant updates + +962 +00:52:44,328 --> 00:52:46,829 +about what's going on, okay. But in either case, first + +963 +00:52:46,831 --> 00:52:49,165 +you're gonna check to see if the hardware's available, and + +964 +00:52:49,167 --> 00:52:51,600 +I'll talk about how you do that. In the polling case, + +965 +00:52:51,602 --> 00:52:55,404 +you're then going to tell the motion manager, okay, I want + +966 +00:52:55,406 --> 00:52:59,275 +accelerometer updates. Okay, and that'll turn that on. And + +967 +00:52:59,277 --> 00:53:02,178 +then you just ask it, what's the current accelerometer, + +968 +00:53:02,180 --> 00:53:03,746 +what's the current accelerometer? + +969 +00:53:03,748 --> 00:53:04,680 +Any time, you can ask it, you want, + +970 +00:53:04,682 --> 00:53:08,117 +you're polling it, basically, asking it. So that's one way, + +971 +00:53:08,119 --> 00:53:11,453 +rare that you would do that way. The second way, again, + +972 +00:53:11,455 --> 00:53:13,088 +you check to see that hardware's available, + +973 +00:53:13,090 --> 00:53:15,758 +then you're gonna set the rate at which you want + +974 +00:53:15,760 --> 00:53:18,194 +the system to tell you about accelerometer or + +975 +00:53:18,196 --> 00:53:23,265 +gyro or magnetometer updates, okay. So five times a second, + +976 +00:53:23,267 --> 00:53:26,001 +30 times a second, probably not much more than that. + +977 +00:53:26,003 --> 00:53:28,771 +I mean, you can only draw it maybe 60 frames a second, + +978 +00:53:28,773 --> 00:53:31,974 +so you're probably not gonna need information much + +979 +00:53:31,976 --> 00:53:32,141 +But you're gonna tell it how often you want it, okay? + +980 +00:53:32,143 --> 00:53:34,910 +more than that. + +981 +00:53:34,912 --> 00:53:36,612 +Then you're gonna give it a closure, okay, + +982 +00:53:36,614 --> 00:53:39,381 +a block of code. And it's going to execute that closure + +983 +00:53:39,383 --> 00:53:42,017 +that many times. Five times a second, 30 times a second. And + +984 +00:53:42,019 --> 00:53:44,887 +that closure, the arguments to it are the current state of + +985 +00:53:44,889 --> 00:53:48,257 +the accelerometer or the current state of the gyro. + +986 +00:53:48,259 --> 00:53:51,794 +Okay, so those are the two ways to do it. So, let's fix, + +987 +00:53:51,796 --> 00:53:54,797 +see how all this works. Checking the availability. You + +988 +00:53:54,799 --> 00:53:58,367 +just ask the CMMotionManager accelerometer Available. + +989 +00:53:58,369 --> 00:54:00,736 +That's a Bool, okay, and it'll tell you yes or no, + +990 +00:54:00,738 --> 00:54:03,839 +or magnetometer available, and that's how you find out. Okay, + +991 +00:54:03,841 --> 00:54:06,475 +so it's as simple as that. So you always wanna check that, + +992 +00:54:06,477 --> 00:54:08,611 +though, because if it's not available and + +993 +00:54:08,613 --> 00:54:11,080 +you start asking for things, you're gonna get errors, + +994 +00:54:11,082 --> 00:54:14,750 +all right? Now, how do you, if you're doing the polling case, + +995 +00:54:14,752 --> 00:54:16,685 +how do you start this thing up? You just say, + +996 +00:54:16,687 --> 00:54:20,422 +start Accelerometer Updates, start Gyro Updates. + +997 +00:54:20,424 --> 00:54:22,424 +And it'll start looking at that hardware. Now, + +998 +00:54:22,426 --> 00:54:26,762 +this is not free. Okay, having this thing start listening to + +999 +00:54:26,764 --> 00:54:31,367 +these pieces of hardware costs battery especially, okay, and + +1000 +00:54:31,369 --> 00:54:33,068 +some CPU too, but it costs battery. + +1001 +00:54:33,070 --> 00:54:36,005 +So don't turn this on unless you're really ready to start + +1002 +00:54:36,007 --> 00:54:39,041 +getting the information, okay? You can ask + +1003 +00:54:39,043 --> 00:54:42,745 +the CMMotionManager whether it is currently, has that + +1004 +00:54:42,747 --> 00:54:46,015 +hardware fired up, basically, by saying, you know, + +1005 +00:54:46,017 --> 00:54:49,184 +Accelerometer active. And that's bool, yes or no. By + +1006 +00:54:49,186 --> 00:54:51,420 +the way, you're noticing all here, you see accelerometer, + +1007 +00:54:51,422 --> 00:54:54,623 +gyro, magnetometer. You also see this thing, deviceMotion. + +1008 +00:54:54,625 --> 00:54:58,761 +Okay, deviceMotion is kind of a special device. + +1009 +00:54:58,763 --> 00:55:01,730 +It's really a combination of the other three. Okay, + +1010 +00:55:01,732 --> 00:55:04,533 +an intelligent combination of the other three, and + +1011 +00:55:04,535 --> 00:55:08,437 +we'll talk about that in a moment here. And + +1012 +00:55:08,439 --> 00:55:09,338 +then to stop the hardware, + +1013 +00:55:09,340 --> 00:55:12,174 +to turn off the accelerometer, turn off the gyro, you just + +1014 +00:55:12,176 --> 00:55:16,845 +say stop whatever updates, okay, and that'll stop it. And + +1015 +00:55:16,847 --> 00:55:20,215 +you wanna do this as soon as you realize, I don't need it, + +1016 +00:55:20,217 --> 00:55:22,451 +even if you only don't need it for a little while and + +1017 +00:55:22,453 --> 00:55:24,887 +you're gonna go back and turn it back on, fine. But + +1018 +00:55:24,889 --> 00:55:26,755 +any time you don't need it, turn it off, okay, + +1019 +00:55:26,757 --> 00:55:29,258 +don't waste the user's battery by having this thing + +1020 +00:55:29,260 --> 00:55:32,861 +working when you're not actually using the data. Okay, + +1021 +00:55:32,863 --> 00:55:36,065 +so that's how you kind of control the hardware. + +1022 +00:55:36,067 --> 00:55:39,134 +Now, again, we're talking about polling here, + +1023 +00:55:39,136 --> 00:55:40,669 +how do I then say, okay, well, + +1024 +00:55:40,671 --> 00:55:42,371 +you got the accelerometer turned on, + +1025 +00:55:42,373 --> 00:55:45,474 +what is the current value of the accelerometer? And you + +1026 +00:55:45,476 --> 00:55:49,311 +just use this CMMotionManager var accelerometer data. + +1027 +00:55:49,313 --> 00:55:53,982 +And it gives you this struct, CMAccelerometerData struct, + +1028 +00:55:53,984 --> 00:55:57,219 +and it's got the acceleration data in x, y, and z, okay? + +1029 +00:55:57,221 --> 00:56:01,824 +So what is this x, y, and z? So here I have a device, okay, + +1030 +00:56:01,826 --> 00:56:05,561 +so, y Okay, y is this axis right here, + +1031 +00:56:05,563 --> 00:56:10,099 +pointing down through the home button, okay? + +1032 +00:56:10,101 --> 00:56:14,236 +So this is the y, okay? It's this vertical axis, okay? + +1033 +00:56:14,238 --> 00:56:18,440 +X is perpendicular to that, cross the device this way. + +1034 +00:56:18,442 --> 00:56:22,878 +So this is y, with the home button being down. This is x. + +1035 +00:56:22,880 --> 00:56:28,951 +Z is out the back. Okay, so if I put this on a table, + +1036 +00:56:28,953 --> 00:56:33,689 +z, what do, what do you think z value would be? + +1037 +00:56:33,691 --> 00:56:37,693 +1.0. Okay, why 1.0? Because x, y, and + +1038 +00:56:37,695 --> 00:56:41,029 +z here are in g. Everyone know what g is, right? 9.8 meters + +1039 +00:56:41,031 --> 00:56:43,966 +per second squared. That's what g is. So z would be 1 + +1040 +00:56:43,968 --> 00:56:47,603 +g if I sit it right there, okay? Because the acceleration + +1041 +00:56:47,605 --> 00:56:51,407 +due to gravity is operating on it. And it does tell you + +1042 +00:56:51,409 --> 00:56:52,741 +the acceleration is due to gravity, + +1043 +00:56:52,743 --> 00:56:54,610 +in addition to the acceleration due to the user + +1044 +00:56:54,612 --> 00:56:56,845 +moving the thing around, okay. Acceleration going all + +1045 +00:56:56,847 --> 00:56:59,882 +over the place, okay? But the acceleration due to gravity + +1046 +00:56:59,884 --> 00:57:04,853 +also counts, so that would be x and y 0, z 1.0. + +1047 +00:57:04,855 --> 00:57:08,157 +Similarly if I do this, this would be y 1.0, x and + +1048 +00:57:08,159 --> 00:57:13,529 +z zero. Okay, so that's the acceleration there. + +1049 +00:57:13,898 --> 00:57:16,298 +You get similar information for gyro, okay. + +1050 +00:57:16,300 --> 00:57:21,870 +The gyro is the rotation of the device, okay. What, what, + +1051 +00:57:21,872 --> 00:57:26,141 +how it's rotating, okay. And this is gonna tell you this in + +1052 +00:57:26,143 --> 00:57:29,378 +radians per second, same axes, okay, radians per second, + +1053 +00:57:29,380 --> 00:57:32,414 +how this thing is rotating. Now there's a bias in here. + +1054 +00:57:32,416 --> 00:57:35,083 +I don't know if people know what a gyro bias is, but + +1055 +00:57:35,085 --> 00:57:36,385 +one simple way to think about it is, + +1056 +00:57:36,387 --> 00:57:40,088 +if I'm moving like this, what if I'm also moving like this? + +1057 +00:57:40,090 --> 00:57:42,658 +Okay, you can see how that might make the gyro think this + +1058 +00:57:42,660 --> 00:57:45,394 +is moving faster than it is, because it's moving this way + +1059 +00:57:45,396 --> 00:57:48,197 +in addition to this. So there's a bias in there. And + +1060 +00:57:48,199 --> 00:57:53,769 +also just the the gyro equipment has a bias built + +1061 +00:57:53,771 --> 00:57:55,637 +into it. Now I'm gonna show you in a way, in a second, + +1062 +00:57:55,639 --> 00:57:59,107 +a way to get this rotation as pure rotation without + +1063 +00:57:59,109 --> 00:58:02,277 +that bias, okay? And also a way to get the accelerometer + +1064 +00:58:02,279 --> 00:58:07,115 +data without gravity. The magnetometer is measuring + +1065 +00:58:07,117 --> 00:58:10,285 +magnetic field, right? This is a thing that can find, you can + +1066 +00:58:10,287 --> 00:58:13,689 +find true north. You can basically find out which way + +1067 +00:58:13,691 --> 00:58:17,526 +each of those axes is pointing relative to true north, + +1068 +00:58:17,528 --> 00:58:20,863 +by measuring the magnetic field around your device, + +1069 +00:58:20,865 --> 00:58:25,834 +okay. Now, I talked about the bias and acceleration due to + +1070 +00:58:25,836 --> 00:58:28,370 +gravity. Here's how you get that out of there. + +1071 +00:58:28,372 --> 00:58:31,974 +Instead of using CMAccelerometer, okay, or + +1072 +00:58:31,976 --> 00:58:36,645 +CMGyro, you use this device CMDeviceMotion. + +1073 +00:58:36,647 --> 00:58:38,313 +And that's the one that's the combination of the other + +1074 +00:58:38,315 --> 00:58:41,316 +three. And by combining them and using the data from all of + +1075 +00:58:41,318 --> 00:58:44,486 +them, it can tell you the part of the acceleration that is + +1076 +00:58:44,488 --> 00:58:48,123 +gravity, and the part of it is the user moving it. Okay, + +1077 +00:58:48,125 --> 00:58:52,928 +because it has the gyro, you see? So it knows from the gyro + +1078 +00:58:52,930 --> 00:58:57,132 +what's going on there. Similar, because it has + +1079 +00:58:57,134 --> 00:59:01,670 +the accelerometer, it can unbias the gyro and + +1080 +00:59:01,672 --> 00:59:06,275 +it reports the gyro to you like an airplane. Any of you + +1081 +00:59:06,277 --> 00:59:08,810 +pilots or anybody flown, piloting, know about it, + +1082 +00:59:08,812 --> 00:59:12,614 +okay. So imagine my iPad here is an airplane, + +1083 +00:59:12,616 --> 00:59:16,618 +okay. The way an airplane describes its motion is it + +1084 +00:59:16,620 --> 00:59:21,123 +has, roll. Roll is this, okay, this axis in the middle, + +1085 +00:59:21,125 --> 00:59:23,225 +how you're rolling. Okay, this is roll. So + +1086 +00:59:23,227 --> 00:59:25,994 +when airplanes turn, they roll and that causes them to turn, + +1087 +00:59:25,996 --> 00:59:29,765 +okay. Then there's pitch, that's up and down, right, + +1088 +00:59:29,767 --> 00:59:31,700 +airplane climbing and descending, + +1089 +00:59:31,702 --> 00:59:35,037 +okay. And then there's yaw. Yaw is when an airplane, + +1090 +00:59:35,039 --> 00:59:37,472 +let's say there's a fierce wind coming this way, + +1091 +00:59:37,474 --> 00:59:38,640 +the airplane wants to go that way but + +1092 +00:59:38,642 --> 00:59:42,644 +it actually has to turn this way to fight this wind. Okay, + +1093 +00:59:42,646 --> 00:59:45,647 +the amount it's turned along this axis is + +1094 +00:59:45,649 --> 00:59:50,552 +the yaw, okay. So you've got roll, pitch and yaw. Okay, + +1095 +00:59:50,554 --> 00:59:54,256 +so that's what we reported to you with CM device motion and + +1096 +00:59:54,258 --> 00:59:56,091 +that is independent of any motion, + +1097 +00:59:56,093 --> 00:59:58,460 +whether the airplane is going fast or sitting still, + +1098 +00:59:58,462 --> 01:00:01,129 +whatever, you're going to get that roll, pitch and yaw, + +1099 +01:00:01,131 --> 01:00:05,467 +okay. So that's device motion, really powerful mechanism. + +1100 +01:00:05,469 --> 01:00:07,302 +And if you're doing anything with a gyro you're probably + +1101 +01:00:07,304 --> 01:00:11,306 +gonna be using Device Motion instead of CM Gyro. Okay, + +1102 +01:00:11,308 --> 01:00:14,142 +magnetic field, with the CM Device Motion, + +1103 +01:00:14,144 --> 01:00:20,048 +it can tell you the accuracy of the magnetic field, okay. + +1104 +01:00:20,684 --> 01:00:23,485 +All right, so, that, we talked about how to poll. + +1105 +01:00:23,487 --> 01:00:25,988 +You just ask for the information you want. + +1106 +01:00:25,990 --> 01:00:28,890 +How about if you wanna be notified 5 times a second, + +1107 +01:00:28,892 --> 01:00:32,594 +or 30 times a second of what's going on, very easy. + +1108 +01:00:32,596 --> 01:00:35,230 +You just call startAccelerometer updates or + +1109 +01:00:35,232 --> 01:00:38,667 +startGyro updates or startdevicemotion updates to + +1110 +01:00:38,669 --> 01:00:39,901 +queue. And you give it a queue, + +1111 +01:00:39,903 --> 01:00:43,505 +this is not a dispatc_queueT, this is an nsoperation queue, + +1112 +01:00:43,507 --> 01:00:46,408 +the object oriented version I talked about. But + +1113 +01:00:46,410 --> 01:00:48,910 +probably you're gonna be passing NSoperationmainqueue, + +1114 +01:00:48,912 --> 01:00:51,546 +or maybe you'll use NSoperationcurrentqueue if + +1115 +01:00:51,548 --> 01:00:54,383 +you're on a different queue. You don't really wanna do this + +1116 +01:00:54,385 --> 01:00:56,618 +on the main queue if you're gonna be doing it at a very + +1117 +01:00:56,620 --> 01:00:59,554 +high rate, like 30 frames a sec, 30 calls a second unless + +1118 +01:00:59,556 --> 01:01:03,258 +you're doing something really simple. Just think about it, + +1119 +01:01:03,260 --> 01:01:05,227 +you don't want the main queue busy doing that. + +1120 +01:01:05,229 --> 01:01:08,296 +But if you're doing 4 or 5 frames a second, absolutely, + +1121 +01:01:08,298 --> 01:01:10,866 +doing something simple, you can do that. + +1122 +01:01:10,868 --> 01:01:13,268 +Then you give it a handler. This is just a block, + +1123 +01:01:13,270 --> 01:01:16,271 +a closure, and you can see that closure as two arguments. + +1124 +01:01:16,273 --> 01:01:18,840 +One is that same CMAccelerometerData we + +1125 +01:01:18,842 --> 01:01:22,811 +saw from before, the x, y and z, and g, that thing, + +1126 +01:01:22,813 --> 01:01:25,480 +okay, and also an error possibly. + +1127 +01:01:25,482 --> 01:01:26,448 +Okay, these are optionals, + +1128 +01:01:26,450 --> 01:01:29,551 +probably if one's nil the other one's not, vice-versa. + +1129 +01:01:29,553 --> 01:01:31,453 +Okay, so this is just closure and inside that closure, + +1130 +01:01:31,455 --> 01:01:34,489 +you can do anything you want with the AccelerometerData. + +1131 +01:01:34,491 --> 01:01:38,427 +All right, similar with the gyro, startGyroUpdatesToQueue, + +1132 +01:01:38,429 --> 01:01:40,495 +you're gonna get the gyro data. + +1133 +01:01:40,497 --> 01:01:43,498 +StartMagnetometerUpdatesToQu- eue, you're gonna get + +1134 +01:01:43,500 --> 01:01:45,600 +the magnetometer data. And of course, + +1135 +01:01:45,602 --> 01:01:49,471 +startDeviceMotionUpdatesToQu- eue, okay. You get the CM, + +1136 +01:01:49,473 --> 01:01:53,108 +CM button DeviceMotion, that's that thing that has vars like + +1137 +01:01:53,110 --> 01:01:57,713 +gravity and attitude for the roll, pitch and yaw, that kind + +1138 +01:01:57,715 --> 01:02:01,316 +of stuff. Just to talk a little bit about the errors, + +1139 +01:02:01,318 --> 01:02:03,251 +you're, of course, gonna want to look in the documentation, + +1140 +01:02:03,253 --> 01:02:06,788 +but some of the errors you can get are like you can't find + +1141 +01:02:06,790 --> 01:02:09,991 +true north maybe, too much interference. + +1142 +01:02:09,993 --> 01:02:12,394 +Maybe this activity's not authorized. Okay, + +1143 +01:02:12,396 --> 01:02:15,997 +maybe user, you're not authorized to actually measure + +1144 +01:02:15,999 --> 01:02:17,999 +the device's motion. Okay, that could be too. + +1145 +01:02:18,001 --> 01:02:20,068 +So you do wanna be able to check for these errors to make + +1146 +01:02:20,070 --> 01:02:24,940 +sure you're actually getting good data. All right, so + +1147 +01:02:24,942 --> 01:02:28,443 +how often you get these closures, called, is set with + +1148 +01:02:28,445 --> 01:02:31,513 +these vars in motion manager, okay. Update interval, + +1149 +01:02:31,515 --> 01:02:34,149 +this is just the number of seconds between calls. + +1150 +01:02:34,151 --> 01:02:38,854 +So like 0.25 would be four times a second, okay? It is + +1151 +01:02:38,856 --> 01:02:42,724 +okay to, to have multiple, closures registered. You could + +1152 +01:02:42,726 --> 01:02:46,328 +say startAccelerometer updates with handler and then call + +1153 +01:02:46,330 --> 01:02:48,029 +it again with another handler. But understand, + +1154 +01:02:48,031 --> 01:02:50,766 +they're all gonna be called at this same interval cuz there's + +1155 +01:02:50,768 --> 01:02:53,869 +only this one motion manager that you're gonna create for + +1156 +01:02:53,871 --> 01:02:54,503 +your whole app, okay. + +1157 +01:02:54,505 --> 01:02:56,505 +All right, so let's take a look at this. + +1158 +01:02:56,507 --> 01:02:59,641 +Let's take DropIt, and let's make the gravity that's in + +1159 +01:02:59,643 --> 01:03:03,979 +DropIt be real gravity, okay. Right now the gravity just + +1160 +01:03:03,981 --> 01:03:06,281 +goes down towards the home button, but let's make it so + +1161 +01:03:06,283 --> 01:03:08,683 +that it's actual gravity. So as I move my thing around, + +1162 +01:03:08,685 --> 01:03:12,921 +those blocks are gonna start swinging towards real gravity. + +1163 +01:03:13,357 --> 01:03:18,760 +All right, so how are we gonna do that? I'm going to + +1164 +01:03:18,762 --> 01:03:25,767 +go to my DropIt view right here, I'm gonna add a new var, + +1165 +01:03:25,769 --> 01:03:31,273 +public var called realGravity, and it's gonna be a Bool, + +1166 +01:03:31,275 --> 01:03:35,410 +okay? I'll start it out being false. And if this is on, + +1167 +01:03:35,412 --> 01:03:38,313 +then I'm gonna use real gravity in my DropIt. + +1168 +01:03:38,315 --> 01:03:40,515 +If it's off, I'm gonna use fake gravity, + +1169 +01:03:40,517 --> 01:03:44,452 +the gravity I already have basically, all right? And so + +1170 +01:03:44,454 --> 01:03:47,455 +let's go back to our controller and + +1171 +01:03:47,457 --> 01:03:48,824 +set this to be true, so + +1172 +01:03:48,826 --> 01:03:52,394 +I'm just gonna do it here in the didSet here, + +1173 +01:03:52,396 --> 01:03:57,599 +gameView.realgravity. Gravity and real, + +1174 +01:03:57,601 --> 01:04:01,870 +realGravity equals true. Okay, so + +1175 +01:04:01,872 --> 01:04:05,006 +we've got realGravity turned on. And how am I gonna make + +1176 +01:04:05,008 --> 01:04:08,743 +this real gravity work? Well anytime someone changes this, + +1177 +01:04:08,745 --> 01:04:11,446 +I'm gonna call some method update real gravity or + +1178 +01:04:11,448 --> 01:04:14,883 +something, and this is the method that's gonna have to + +1179 +01:04:14,885 --> 01:04:17,853 +turn the accelerometer on to start using it. Okay? + +1180 +01:04:17,855 --> 01:04:22,557 +So that's a private funk update real gravity. + +1181 +01:04:22,559 --> 01:04:23,625 +Okay, so this is going to be the guts. + +1182 +01:04:23,627 --> 01:04:26,494 +This is going to be the thing that's actually doing + +1183 +01:04:26,496 --> 01:04:27,729 +the work here. All right, so + +1184 +01:04:27,731 --> 01:04:30,465 +what do update real gravity going to do? Well, + +1185 +01:04:30,467 --> 01:04:32,434 +it's going to do something with the accelerometer. And + +1186 +01:04:32,436 --> 01:04:34,669 +we to use the accelerometer to get the gravity. + +1187 +01:04:34,671 --> 01:04:35,804 +I'm not going to use device motion, + +1188 +01:04:35,806 --> 01:04:40,075 +okay, just to make it simple, we'll use the accelerometer. + +1189 +01:04:40,077 --> 01:04:43,211 +We want the real gravity anyway so we'll use that. So I + +1190 +01:04:43,213 --> 01:04:46,281 +need a private var here which is that motion manager. As I + +1191 +01:04:46,283 --> 01:04:48,984 +told you, you need a motion manager to do any of this. So, + +1192 +01:04:48,986 --> 01:04:52,087 +we'll just say that equals CMMotionManager. + +1193 +01:04:52,089 --> 01:04:54,122 +I'm not using any of this in + +1194 +01:04:54,124 --> 01:04:56,391 +any other part of my app. So I'm putting it here. + +1195 +01:04:56,393 --> 01:04:59,227 +Again, if I was using it in two different places, + +1196 +01:04:59,229 --> 01:05:02,964 +I'd have to make this be some sort of shared resource. + +1197 +01:05:02,966 --> 01:05:04,699 +Notice it is complaining right here, okay? + +1198 +01:05:04,701 --> 01:05:05,934 +Does never heard of a CMMotionManager and + +1199 +01:05:05,936 --> 01:05:08,003 +it doesn't know what the heck we're talking about. + +1200 +01:05:08,005 --> 01:05:11,039 +This is because this is in a different framework, + +1201 +01:05:11,041 --> 01:05:15,677 +import,CcoreMotion, okay? All this CoreMotion stuff you have + +1202 +01:05:15,679 --> 01:05:19,848 +to import CoreMotion. All right, so we have our + +1203 +01:05:19,850 --> 01:05:22,450 +motion manager right here. How are we going to use our + +1204 +01:05:22,452 --> 01:05:25,987 +motion manager to grab that accelerometer, information? + +1205 +01:05:25,989 --> 01:05:31,226 +So if we want real gravity, then we're going to do that. + +1206 +01:05:31,228 --> 01:05:32,928 +By the way, if we don't want real gravity, + +1207 +01:05:32,930 --> 01:05:35,997 +then I'm going to tell the motion manager to stop + +1208 +01:05:35,999 --> 01:05:40,001 +accelerometer updates. Again, I always want to stop that + +1209 +01:05:40,003 --> 01:05:43,939 +updating happening any time I don't want the updates, okay. + +1210 +01:05:43,941 --> 01:05:46,741 +So we try to keep that off as much as possible. But if we do + +1211 +01:05:46,743 --> 01:05:51,579 +want real gravity, then first I'm gonna check to see, if + +1212 +01:05:51,581 --> 01:05:57,886 +the motionManager accelerometer is available. + +1213 +01:05:57,888 --> 01:06:02,257 +Okay, as promised, this is first thing we need to do. + +1214 +01:06:02,259 --> 01:06:03,758 +Actually I'm also going to see here if + +1215 +01:06:03,760 --> 01:06:06,628 +the accelerometer is already active. Cuz maybe I already + +1216 +01:06:06,630 --> 01:06:09,364 +called updateRealGravity and it's already running. So + +1217 +01:06:09,366 --> 01:06:14,903 +I'm gonna actually say and the motionManager.accelerometerAc- + +1218 +01:06:14,905 --> 01:06:19,607 +tive is false. Okay? So if the accelerometer is available and + +1219 +01:06:19,609 --> 01:06:20,075 +it's not already running, + +1220 +01:06:20,077 --> 01:06:24,079 +then I need to fire this thing up, okay? So let's fire it up. + +1221 +01:06:24,081 --> 01:06:27,949 +Let's start with our update interval. So I'm going to have + +1222 +01:06:27,951 --> 01:06:30,919 +the accelerometer update interval be, I, + +1223 +01:06:30,921 --> 01:06:35,090 +maybe 0.25, 0.2 is probably enough. You know, gravity + +1224 +01:06:35,092 --> 01:06:38,193 +doesn't really need to change that much more often than that + +1225 +01:06:38,195 --> 01:06:40,161 +as I am moving my device around. This is a number + +1226 +01:06:40,163 --> 01:06:43,031 +I could play with. Again, this should probably, not probably, + +1227 +01:06:43,033 --> 01:06:45,600 +definitely be a constant but we're time constrained here so + +1228 +01:06:45,602 --> 01:06:50,872 +I'm not gonna do that. So now I'm just gonna have the motion + +1229 +01:06:50,874 --> 01:06:54,309 +manager start giving me updates to queue, + +1230 +01:06:54,311 --> 01:06:57,612 +okay? So this is how I started updating. Now, what queue am I + +1231 +01:06:57,614 --> 01:06:59,581 +gonna use? I'm gonna use the main cue here cuz + +1232 +01:06:59,583 --> 01:07:01,916 +I'm only doing it four times a second and I'm only just + +1233 +01:07:01,918 --> 01:07:04,052 +gonna set that gravity thing, that's all I'm gonna do, so + +1234 +01:07:04,054 --> 01:07:07,222 +that's really lightweight so I can just use the main queue. + +1235 +01:07:07,224 --> 01:07:11,059 +So, enter operation queue main queue. Okay, + +1236 +01:07:11,061 --> 01:07:14,362 +here's the handler, the CM handler. I always recommend + +1237 +01:07:14,364 --> 01:07:17,098 +double clicking on these things because it fills + +1238 +01:07:17,100 --> 01:07:21,603 +out really nicely. Your arguments and + +1239 +01:07:21,605 --> 01:07:25,106 +stuff like that. I'm also going to use the closing or + +1240 +01:07:25,108 --> 01:07:29,911 +the trailing closure syntax here to do this, all right. + +1241 +01:07:29,913 --> 01:07:32,747 +So I'm going to start this accelerometer, + +1242 +01:07:32,749 --> 01:07:34,616 +here is my closure that I have to do, + +1243 +01:07:34,618 --> 01:07:39,621 +okay? So, this accelerometer data, I'll call it data. This + +1244 +01:07:39,623 --> 01:07:44,459 +error I'll call error. Okay, so, how am I gonna do this? + +1245 +01:07:44,461 --> 01:07:48,630 +Well, this data might be nil, it's an optional. So, I'm + +1246 +01:07:48,632 --> 01:07:51,132 +gonna see if I can get the accelerometer data first. + +1247 +01:07:51,134 --> 01:07:54,702 +So, let's say if I can let, we'll call the x, + +1248 +01:07:54,704 --> 01:07:57,539 +I'm only caring about x and y. Don't care about z, okay, + +1249 +01:07:57,541 --> 01:08:01,242 +because I'm gonna have the my little drop it is two + +1250 +01:08:01,244 --> 01:08:03,244 +dimensional so it doesn't care about z. So + +1251 +01:08:03,246 --> 01:08:07,582 +if I can let dx equal the data acceleration in x, and + +1252 +01:08:07,584 --> 01:08:12,020 +also we can let dy equal the data's acceleration in y so + +1253 +01:08:12,022 --> 01:08:16,124 +then I'm just getting simultaneously getting and + +1254 +01:08:16,126 --> 01:08:19,794 +checking to be sure the data is not nil, so + +1255 +01:08:19,796 --> 01:08:21,062 +I've got the dx a new y. + +1256 +01:08:21,064 --> 01:08:28,803 +Let's first try to just set the drop behaviors gravity's, + +1257 +01:08:28,805 --> 01:08:33,808 +gravity direction, to just be a CG vector + +1258 +01:08:33,810 --> 01:08:37,812 +which is dx and dy, okay? So we're gonna try this first. + +1259 +01:08:37,814 --> 01:08:41,483 +Now, this is not gonna work because gravity is private. So + +1260 +01:08:41,485 --> 01:08:44,285 +let's just go over to our behavior, falling object + +1261 +01:08:44,287 --> 01:08:47,655 +behaviour here. I'm gonna make this not be private. Okay, + +1262 +01:08:47,657 --> 01:08:50,191 +just for expediency. Maybe we wanna make some other public + +1263 +01:08:50,193 --> 01:08:53,128 +API like we did with Glider here. I'm just gonna make this + +1264 +01:08:53,130 --> 01:08:57,932 +public. Make it a little, go a little faster. All right, so + +1265 +01:08:57,934 --> 01:09:01,669 +here we are, we're saving this, gravity here. + +1266 +01:09:02,305 --> 01:09:05,206 +Yeah good one, that's what, okay got it. + +1267 +01:09:05,208 --> 01:09:09,511 +Very good catch, bonus points, all right, so right. + +1268 +01:09:09,513 --> 01:09:13,848 +So there's that, one other thing I wanna be careful of + +1269 +01:09:13,850 --> 01:09:17,986 +here is memory cycle. Okay I've got this accelerometer, + +1270 +01:09:17,988 --> 01:09:20,655 +cuz motion manager has accelerometer that that + +1271 +01:09:20,657 --> 01:09:23,925 +thing has a hold of this closure, I have a hold of it. + +1272 +01:09:23,927 --> 01:09:25,426 +Okay I have a hold the of motion manger. And + +1273 +01:09:25,428 --> 01:09:29,597 +Motion manager has a hold of me, okay? So that's not good. + +1274 +01:09:29,599 --> 01:09:33,268 +Again, we can do unowned to solve this one. Oops don't put + +1275 +01:09:33,270 --> 01:09:37,505 +it there. Unowned goes over here. We can do unowned + +1276 +01:09:37,507 --> 01:09:42,177 +self here because as soon as self leaves the heap, + +1277 +01:09:42,179 --> 01:09:44,512 +this motionManager is gonna leave the heap with it, + +1278 +01:09:44,514 --> 01:09:46,915 +which means this closure is gonna go out too. + +1279 +01:09:46,917 --> 01:09:49,417 +So this closure will never get executed with self not in + +1280 +01:09:49,419 --> 01:09:52,787 +the heap. Once self leaves the heap, this guy goes with it. + +1281 +01:09:52,789 --> 01:09:56,224 +So we can do unowned here, to do that. The only other + +1282 +01:09:56,226 --> 01:10:00,562 +thing I want to do here is if, I, I want to try and turn this + +1283 +01:10:00,564 --> 01:10:04,299 +accelerator updates off as much as possible. So another + +1284 +01:10:04,301 --> 01:10:08,436 +time I want to turn it off is if I'm not animating, right? + +1285 +01:10:08,438 --> 01:10:11,940 +If I have my dropBehavior, okay, and it's not currently + +1286 +01:10:11,942 --> 01:10:15,243 +animating, I do not want to be continuing to do this. + +1287 +01:10:15,245 --> 01:10:19,814 +So, I'm gonna say only do this if my dropBehavior, + +1288 +01:10:19,816 --> 01:10:24,185 +it's dynamic animator is not nil. That's how you can tell + +1289 +01:10:24,187 --> 01:10:25,887 +whether a behaviour is currently being animated. + +1290 +01:10:25,889 --> 01:10:29,490 +If it has a dynamic animator, it's being animated. If not, + +1291 +01:10:29,492 --> 01:10:34,028 +it's not. So, if it's not nil, then we'll do this. Otherwise, + +1292 +01:10:34,030 --> 01:10:38,099 +I'm going to stop this motion manager, okay? + +1293 +01:10:38,101 --> 01:10:41,703 +Stop accelerometer updates in this motion manager. You see + +1294 +01:10:41,705 --> 01:10:45,039 +how I'm trying to stop this thing as much as possible? + +1295 +01:10:45,041 --> 01:10:46,407 +The only thing about this, though, + +1296 +01:10:46,409 --> 01:10:49,310 +is if I do stop it because I stop animating, then I better + +1297 +01:10:49,312 --> 01:10:51,646 +be sure that when I start animating up again. + +1298 +01:10:51,648 --> 01:10:53,181 +Remember this is that animating bar, + +1299 +01:10:53,183 --> 01:10:54,782 +you set it to true to start animating. + +1300 +01:10:54,784 --> 01:10:58,152 +I better update my real gravity here to make sure that + +1301 +01:10:58,154 --> 01:11:01,556 +I start the accelerometer back up again, okay? So + +1302 +01:11:01,558 --> 01:11:03,124 +that allows me to start and stop animating. + +1303 +01:11:03,126 --> 01:11:06,394 +It stops the accelerometers, every time I restart it, + +1304 +01:11:06,396 --> 01:11:09,264 +it starts them again, okay? So let's try this and + +1305 +01:11:09,266 --> 01:11:11,299 +see if it works. Now, this is the first time in this + +1306 +01:11:11,301 --> 01:11:12,200 +class where I'm having to actually, + +1307 +01:11:12,202 --> 01:11:15,903 +I can't do it in a simulator because the simulator has no, + +1308 +01:11:15,905 --> 01:11:17,505 +accelerometer or anything like that, so + +1309 +01:11:17,507 --> 01:11:21,376 +we're gonna be doing it here on this other device. + +1310 +01:11:21,378 --> 01:11:26,147 +Let me run over here and show you this. All right, so + +1311 +01:11:26,149 --> 01:11:30,551 +let's run this on our device here, here we go, + +1312 +01:11:30,553 --> 01:11:33,187 +it's coming up here, there it is, we see our little circle, + +1313 +01:11:33,189 --> 01:11:38,793 +if I tap, it's not working. What's going on here? + +1314 +01:11:38,795 --> 01:11:41,396 +Why wouldn't that be working? I got the gravity going on + +1315 +01:11:41,398 --> 01:11:46,501 +there, hm. Maybe if I turn my thing upside down, woah! + +1316 +01:11:46,503 --> 01:11:48,703 +That worked, I turned my iPad upside down, and + +1317 +01:11:48,705 --> 01:11:52,874 +all of a sudden gravity seems to be backwards here, okay? + +1318 +01:11:52,876 --> 01:11:57,111 +Now why would gravity be backwards? The answer is, + +1319 +01:11:57,113 --> 01:12:01,282 +because our drawing coordinate system has 0,0 in the upper + +1320 +01:12:01,284 --> 01:12:04,752 +left. So this is working fine, it's falling down toward zero, + +1321 +01:12:04,754 --> 01:12:08,022 +it's just that's in the upper left. So we need to add some + +1322 +01:12:08,024 --> 01:12:12,126 +code here that knows what the orientation of our device is, + +1323 +01:12:12,128 --> 01:12:16,297 +and adjusts, okay, for the fact that it's upside down, + +1324 +01:12:16,299 --> 01:12:19,567 +basically. Also, when we turn sideways, and + +1325 +01:12:19,569 --> 01:12:21,369 +we're looking at landscape mode, + +1326 +01:12:21,371 --> 01:12:24,172 +we wanna make sure that's doing the right thing as well. + +1327 +01:12:24,174 --> 01:12:28,843 +So let's put that in here. Okay, that goes right, so + +1328 +01:12:28,845 --> 01:12:32,613 +let's put that right in here. Okay, we've got our dx and dy. + +1329 +01:12:32,615 --> 01:12:36,751 +All I'm gonna do here is I'm gonna switch on my device's, + +1330 +01:12:36,753 --> 01:12:40,621 +this is how you get the current device's orientation, + +1331 +01:12:40,623 --> 01:12:43,124 +okay. This will return the orientation of the current + +1332 +01:12:43,126 --> 01:12:48,196 +device. And so for example, in the case of portrait, okay, + +1333 +01:12:48,198 --> 01:12:51,666 +we know that portrait is upside down, so + +1334 +01:12:51,668 --> 01:12:54,535 +I'm gonna say dy = -dy in portrait. + +1335 +01:12:54,537 --> 01:12:58,639 +In the case of portrait upside down, everything's fine. + +1336 +01:12:58,641 --> 01:13:00,875 +We know that that works, okay. Portrait upside down, + +1337 +01:13:00,877 --> 01:13:03,611 +we've got the right thing. How about LandscapeLeft, + +1338 +01:13:03,613 --> 01:13:07,715 +or LandscapeRight, let's say. In LandscapeRight, x and + +1339 +01:13:07,717 --> 01:13:11,819 +y are swapped, right, because I've turned it sideways, so + +1340 +01:13:11,821 --> 01:13:14,789 +now it's the x of my device that's down. So + +1341 +01:13:14,791 --> 01:13:17,759 +I need to swap them. There's actually a nice method here or + +1342 +01:13:17,761 --> 01:13:21,496 +function called swap which will swap two variables, okay. + +1343 +01:13:21,498 --> 01:13:29,370 +And then in LandscapeLeft, not only are they swapped, + +1344 +01:13:29,372 --> 01:13:34,675 +but also dy has to be -dy, okay? + +1345 +01:13:34,677 --> 01:13:38,279 +In other cases, there are other cases like FaceUp and + +1346 +01:13:38,281 --> 01:13:41,816 +FaceDown. Those are orientations. In those cases, + +1347 +01:13:41,818 --> 01:13:45,119 +there should be no gravity going on. So I'm gonna say dx + +1348 +01:13:45,121 --> 01:13:49,323 += 0, dy = 0. Okay, because my thing is flat or whatever. + +1349 +01:13:49,325 --> 01:13:52,827 +Now, notice I'm modifying dy and dx in here, but I said + +1350 +01:13:52,829 --> 01:13:57,298 +if let, just to remind you all you can change this to var, + +1351 +01:13:57,300 --> 01:14:01,502 +if var. Exactly the same as if let, it's just that + +1352 +01:14:01,504 --> 01:14:05,640 +these will now be vars that inside here you can modify. + +1353 +01:14:05,642 --> 01:14:10,545 +Okay, everybody got that? Okay, so + +1354 +01:14:10,547 --> 01:14:18,119 +let's try that. All right, + +1355 +01:14:18,121 --> 01:14:21,222 +here we go. Drop it, it's working! Look at this. + +1356 +01:14:21,224 --> 01:14:23,691 +Dropping some more things, I have my thing face up. + +1357 +01:14:23,693 --> 01:14:26,694 +Okay, now I'm going to turn my thing upside down. + +1358 +01:14:26,696 --> 01:14:30,531 +Let's see if they all fall down. And they do! Excellent. + +1359 +01:14:30,533 --> 01:14:36,003 +Okay, now I'm gonna turn it sideways. Bam. Okay, + +1360 +01:14:36,005 --> 01:14:41,042 +sideways around the other way. Okay. Now, + +1361 +01:14:41,044 --> 01:14:44,011 +one thing that's interesting about this is I actually have + +1362 +01:14:44,013 --> 01:14:47,648 +my rotation locked. If I unlock my rotation, + +1363 +01:14:47,650 --> 01:14:49,784 +then my view is gonna change. Watch this. + +1364 +01:14:49,786 --> 01:14:54,555 +See? So since it switched, all the views moved to the bottom. + +1365 +01:14:54,557 --> 01:14:57,291 +So it didn't actually do much. Now, I can try and + +1366 +01:14:57,293 --> 01:15:00,795 +move it around without changing my orientation, but + +1367 +01:15:00,797 --> 01:15:02,997 +as soon as my orientation changes, + +1368 +01:15:02,999 --> 01:15:07,368 +it's gonna jump around. Got that? + +1369 +01:15:07,370 --> 01:15:11,606 +Okay? All right, that's it for + +1370 +01:15:11,608 --> 01:15:14,342 +today. You have everything you need to know, I hope, + +1371 +01:15:14,344 --> 01:15:18,246 +to do your assignment six. If you have any questions, + +1372 +01:15:18,248 --> 01:15:20,781 +I'll be here as usual. >> For + +1373 +01:15:20,783 --> 01:15:20,814 +more, please visit us at Stanford.edu. + diff --git a/subtitles/15. Application Lifecycle, Alerts, CloudKit.srt b/subtitles/15. Application Lifecycle, Alerts, CloudKit.srt new file mode 100644 index 0000000..1515827 --- /dev/null +++ b/subtitles/15. Application Lifecycle, Alerts, CloudKit.srt @@ -0,0 +1,6580 @@ +1 +00:00:00,001 --> 00:00:08,173 +[SOUND] Stanford University. >> All right, + +2 +00:00:08,175 --> 00:00:13,145 +well welcome to lecture 15 CS193P Spring of 2016. + +3 +00:00:13,147 --> 00:00:16,915 +So today we have three major topics. + +4 +00:00:16,917 --> 00:00:18,350 +One is the Application Life Cycle. + +5 +00:00:18,352 --> 00:00:20,786 +Remember we talked about the View Controller Life Cycle. + +6 +00:00:20,788 --> 00:00:23,956 +How View Controller comes into existence and goes on and + +7 +00:00:23,958 --> 00:00:25,090 +off screen and all that stuff. Well, + +8 +00:00:25,092 --> 00:00:27,726 +an Application goes through a similar sort of life cycle. + +9 +00:00:27,728 --> 00:00:30,596 +And we're going to talk about that. And along the way I'm + +10 +00:00:30,598 --> 00:00:32,998 +also going to talk about NS Notification, which + +11 +00:00:33,000 --> 00:00:35,834 +is that radio station from the NBC that we talked about + +12 +00:00:35,836 --> 00:00:37,369 +at the very beginning of the Quarter. + +13 +00:00:37,371 --> 00:00:40,239 +And we're going to talk about alerts. And I'm going to + +14 +00:00:40,241 --> 00:00:41,974 +switch gears a little from what I had said and + +15 +00:00:41,976 --> 00:00:44,977 +talk today about Cloud Kit. Because quite a few of you + +16 +00:00:44,979 --> 00:00:46,645 +have come up to me in your final projects and said. + +17 +00:00:46,647 --> 00:00:50,582 +Well, I want to do a little light weight backend over + +18 +00:00:50,584 --> 00:00:50,716 +maybe something simple like, some sort of messaging or + +19 +00:00:50,718 --> 00:00:53,552 +the network, + +20 +00:00:53,554 --> 00:00:57,656 +something like that. and cloud kit is a pretty cool way and + +21 +00:00:57,658 --> 00:01:00,526 +pretty simple way, actually, to do that, especially for + +22 +00:01:00,528 --> 00:01:01,493 +something like your final project, + +23 +00:01:01,495 --> 00:01:07,199 +which is a proof of concept vehicle where you + +24 +00:01:07,201 --> 00:01:09,868 +just need something simple where you can make it work and + +25 +00:01:09,870 --> 00:01:11,103 +you can always replace it with something much + +26 +00:01:11,105 --> 00:01:13,605 +more powerful networking-wise later. All right. + +27 +00:01:13,607 --> 00:01:15,140 +So I'm gonna talk about those three things today. And + +28 +00:01:15,142 --> 00:01:20,579 +then on Wednesday I will demo all these things. All right? + +29 +00:01:20,581 --> 00:01:23,082 +All right. So let's talk about this in this notification + +30 +00:01:23,084 --> 00:01:25,851 +thing. If you remember back to the very first lecture or + +31 +00:01:25,853 --> 00:01:28,520 +the second lecture when I talked about MVC, + +32 +00:01:28,522 --> 00:01:31,924 +there was this little guy here on the model + +33 +00:01:31,926 --> 00:01:34,526 +that looked a little round thing right here. + +34 +00:01:34,528 --> 00:01:36,528 +Which I called a radio station model for + +35 +00:01:36,530 --> 00:01:40,499 +communication from the model to the controller usually. + +36 +00:01:40,501 --> 00:01:43,068 +Guess where it goes and so we're gonna talk about + +37 +00:01:43,070 --> 00:01:46,238 +actually how this little radio station works in code, + +38 +00:01:46,240 --> 00:01:47,973 +how we do this thing in code. Okay, + +39 +00:01:47,975 --> 00:01:51,376 +it's called NSNotification, all right? It's a radio + +40 +00:01:51,378 --> 00:01:54,113 +station, the radio station by the way is not only good for + +41 +00:01:54,115 --> 00:01:55,547 +the model communicating with the controller, + +42 +00:01:55,549 --> 00:01:59,084 +it's also good for the system IOS to communicate with your + +43 +00:01:59,086 --> 00:02:03,188 +app. So you'll see a lot of communication from IOS to your + +44 +00:02:03,190 --> 00:02:07,292 +app as a whole using these notifications as well. So + +45 +00:02:07,294 --> 00:02:09,995 +let's first of all talk about how you tune into a radio + +46 +00:02:09,997 --> 00:02:12,264 +station. In other words if you want to listen to what's being + +47 +00:02:12,266 --> 00:02:14,733 +broadcast on a radio station, how do you do that? It's + +48 +00:02:14,735 --> 00:02:17,970 +actually quite simple, you're gonna get this in instance of + +49 +00:02:17,972 --> 00:02:21,273 +this object right here the NS notification center by saying + +50 +00:02:21,275 --> 00:02:23,876 +NSNotificationCenter.defaultC- enter(), okay. + +51 +00:02:23,878 --> 00:02:27,379 +And this is gonna get to this shared NS notification center, + +52 +00:02:27,381 --> 00:02:28,680 +and then you're gonna send that + +53 +00:02:28,682 --> 00:02:33,485 +message right here addObserverForName, okay. So + +54 +00:02:33,487 --> 00:02:38,757 +addObserverForName Takes a string which is the name + +55 +00:02:38,759 --> 00:02:43,195 +of the radio station. And it takes a block down here, + +56 +00:02:43,197 --> 00:02:46,031 +the send this notification block which is the block + +57 +00:02:46,033 --> 00:02:49,067 +that's going to be executed when there are broadcasts on + +58 +00:02:49,069 --> 00:02:52,004 +the radio station. So it really couldn't be any + +59 +00:02:52,006 --> 00:02:56,642 +simpler. It returns something that's an NS object protocol. + +60 +00:02:56,644 --> 00:02:58,944 +Optional, okay, but basically it's just a cookie. + +61 +00:02:58,946 --> 00:03:01,914 +You can almost think of it as any object. You'll kind of + +62 +00:03:01,916 --> 00:03:06,418 +need the return value of this, so you can stop observing this + +63 +00:03:06,420 --> 00:03:08,820 +radio station because you're listening when you, + +64 +00:03:08,822 --> 00:03:11,156 +when you send this, to this default center there. + +65 +00:03:11,158 --> 00:03:12,824 +You start listening to the radio station, well, + +66 +00:03:12,826 --> 00:03:14,059 +you have to be able to stop listening and + +67 +00:03:14,061 --> 00:03:17,229 +to do that, you need this little return value of this + +68 +00:03:17,231 --> 00:03:18,163 +add observer. For + +69 +00:03:18,165 --> 00:03:21,767 +name, guy right there. Okay, what are the other two + +70 +00:03:21,769 --> 00:03:23,869 +arguments here besides the name of the radio station and + +71 +00:03:23,871 --> 00:03:28,040 +the block of code to execute? One is the senders, + +72 +00:03:28,042 --> 00:03:30,509 +okay, in other words, the broadcasters that you're + +73 +00:03:30,511 --> 00:03:32,911 +You're interested in. Now you can just specify nil here, + +74 +00:03:32,913 --> 00:03:35,714 +then you'll listen to any radio station with that name. + +75 +00:03:35,716 --> 00:03:38,784 +Anybody broadcasting on that radio station you're going to + +76 +00:03:38,786 --> 00:03:40,519 +listen to. But if you put an object here, + +77 +00:03:40,521 --> 00:03:43,188 +it would only be if that particular object is + +78 +00:03:43,190 --> 00:03:45,924 +broadcasting on that radio station. + +79 +00:03:45,926 --> 00:03:48,560 +Okay? So, it depends on the kind + +80 +00:03:48,562 --> 00:03:51,363 +of environment that you're listening here as to whether + +81 +00:03:51,365 --> 00:03:52,664 +it makes sense to put something there. + +82 +00:03:52,666 --> 00:03:53,799 +And I'll show you some examples. + +83 +00:03:53,801 --> 00:03:57,135 +It'll make more sense. Then there's this queue right here. + +84 +00:03:57,137 --> 00:03:59,137 +This queue is gonna be the queue, + +85 +00:03:59,139 --> 00:04:03,976 +that this closure is going to be executed on. Okay? So + +86 +00:04:03,978 --> 00:04:07,079 +often times if you're doing UI stuff in here you'll obviously + +87 +00:04:07,081 --> 00:04:09,982 +want to say NSOperationQueue.MainQueue. + +88 +00:04:09,984 --> 00:04:13,785 +Okay? You can also pass nil here. You can see the question + +89 +00:04:13,787 --> 00:04:16,355 +mark there, so this could be nil. If you pass mail here, + +90 +00:04:16,357 --> 00:04:20,058 +then it will execute this closure on the same queue + +91 +00:04:20,060 --> 00:04:23,061 +as the radio station broadcaster, + +92 +00:04:23,063 --> 00:04:24,062 +which is a little bit odd, okay, + +93 +00:04:24,064 --> 00:04:26,231 +because sometimes the radio station's broadcasting and + +94 +00:04:26,233 --> 00:04:28,767 +you're not really sure what queue they're on, but + +95 +00:04:28,769 --> 00:04:31,336 +that's what meant, so usually we're going to have NS + +96 +00:04:31,338 --> 00:04:34,806 +operation main queue in here when you're listening. Now, + +97 +00:04:34,808 --> 00:04:37,843 +inside this closure, you can see there is one argument. + +98 +00:04:37,845 --> 00:04:39,544 +The argument is an NSNotification. So, + +99 +00:04:39,546 --> 00:04:43,148 +an NSNotification encapsulates the data that's coming across + +100 +00:04:43,150 --> 00:04:46,418 +in a radio station broadcast. And, there's really only one + +101 +00:04:46,420 --> 00:04:48,620 +interesting thing inside, there's a few in here you + +102 +00:04:48,622 --> 00:04:51,356 +can look in the documentation, but the main interesting thing + +103 +00:04:51,358 --> 00:04:54,960 +in this notification, is this thing called it's userInfo, + +104 +00:04:54,962 --> 00:04:58,330 +notification.userInfo. That's a dictionary, okay, + +105 +00:04:58,332 --> 00:05:02,668 +keys are NSObjects the values are AnyObject, okay. And + +106 +00:05:02,670 --> 00:05:05,137 +in that dictionary is any information that the radio + +107 +00:05:05,139 --> 00:05:07,806 +station broadcaster wants you to have, okay. So they're + +108 +00:05:07,808 --> 00:05:10,609 +gonna have to let you know what the keys of this are so + +109 +00:05:10,611 --> 00:05:13,645 +you can look in there and then you can get certain values. + +110 +00:05:13,647 --> 00:05:16,181 +So everybody who broadcasts. On a radio station, + +111 +00:05:16,183 --> 00:05:17,983 +it's going to tell you the name of the radio station. + +112 +00:05:17,985 --> 00:05:20,819 +This string right here, addObserverForName(String. + +113 +00:05:20,821 --> 00:05:23,789 +And then they're going to tell you the keys that you can use + +114 +00:05:23,791 --> 00:05:27,225 +to look inside this notification.userinfo. Okay, + +115 +00:05:27,227 --> 00:05:29,394 +those are all things that the radio station broadcaster has + +116 +00:05:29,396 --> 00:05:32,564 +to tell you if you want to listen to that broadcast and + +117 +00:05:32,566 --> 00:05:36,068 +make any sense of it, okay. All right, so + +118 +00:05:36,070 --> 00:05:40,272 +here's an example of listening to a radio station. So + +119 +00:05:40,274 --> 00:05:43,775 +there happens to be a radio station that broadcasts + +120 +00:05:43,777 --> 00:05:46,712 +whenever the user goes into their setting and + +121 +00:05:46,714 --> 00:05:50,482 +sets their font size. This is, did you see on the right, + +122 +00:05:50,484 --> 00:05:52,484 +there's a screen in the general settings + +123 +00:05:52,486 --> 00:05:54,086 +app that's under accessibility I think, + +124 +00:05:54,088 --> 00:05:56,655 +font sizes or something like that. And you can see there's + +125 +00:05:56,657 --> 00:05:58,824 +this slider down here. You can make your fonts bigger or + +126 +00:05:58,826 --> 00:06:02,260 +smaller. Okay, well when you change this a radio station + +127 +00:06:02,262 --> 00:06:05,197 +broadcast goes out to all the apps saying the, + +128 +00:06:05,199 --> 00:06:08,734 +what's called, content size category did change. + +129 +00:06:08,736 --> 00:06:11,036 +So this is the name of the radio station, + +130 +00:06:11,038 --> 00:06:14,573 +UIContentSizeCategoryDidChang- eNotification. Okay, + +131 +00:06:14,575 --> 00:06:18,944 +that's a constant somewhere in IOS. And it is + +132 +00:06:18,946 --> 00:06:21,880 +a string that just finds the name of this radio station. + +133 +00:06:21,882 --> 00:06:24,983 +So if you wanted to find out when the user changes + +134 +00:06:24,985 --> 00:06:29,354 +their font size you would just do defaultcenter here, + +135 +00:06:29,356 --> 00:06:31,990 +addObserverForName listen to that radio station. + +136 +00:06:31,992 --> 00:06:35,260 +The sender is going to be the UI application when the system + +137 +00:06:35,262 --> 00:06:37,929 +talks to you it usually talks to you from UI application, + +138 +00:06:37,931 --> 00:06:41,266 +but you might put nill right here because if anybody wants + +139 +00:06:41,268 --> 00:06:43,969 +to tell you that the content size category did change, + +140 +00:06:43,971 --> 00:06:45,837 +you're probably interested so you might say nill for + +141 +00:06:45,839 --> 00:06:48,807 +the object there. And then main queue you're almost + +142 +00:06:48,809 --> 00:06:49,941 +certainly gonna be listening for + +143 +00:06:49,943 --> 00:06:52,778 +broadcast of this radio station, on your main queue, + +144 +00:06:52,780 --> 00:06:55,680 +because when the font size changes we are gonna do + +145 +00:06:55,682 --> 00:06:57,416 +some UI thing. You're gonna react to it and + +146 +00:06:57,418 --> 00:07:01,586 +of course we know you can only do UI on the main queue. Okay? + +147 +00:07:01,588 --> 00:07:04,656 +So here's my closure, and right here I see I'm getting + +148 +00:07:04,658 --> 00:07:08,093 +the notification user info, inside there is a key, again, + +149 +00:07:08,095 --> 00:07:12,297 +this broadcast that's, you know, in some IOS place there. + +150 +00:07:12,299 --> 00:07:15,767 +UI content size category new value key, and it'll tell you + +151 +00:07:15,769 --> 00:07:19,738 +the new value of this size category of the font, + +152 +00:07:19,740 --> 00:07:24,943 +okay? It could be for example, UIContentSizeCategorySmall. + +153 +00:07:24,945 --> 00:07:27,012 +That's one of the size categories. And + +154 +00:07:27,014 --> 00:07:29,548 +once you get that new category, then you can react + +155 +00:07:29,550 --> 00:07:33,952 +to it, okay. Redraw something, whatever you wanna do. + +156 +00:07:33,954 --> 00:07:35,854 +By the way, if you're using preferred font, + +157 +00:07:35,856 --> 00:07:39,391 +remember we switched to using system font in our early apps? + +158 +00:07:39,393 --> 00:07:42,294 +We started using preferred fonts like the body font and + +159 +00:07:42,296 --> 00:07:42,360 +You remember all that? Those fonts are really cool because + +160 +00:07:42,362 --> 00:07:45,096 +the headline font. + +161 +00:07:45,098 --> 00:07:48,900 +they automatically are going to adjust to this size change. + +162 +00:07:48,902 --> 00:07:50,802 +So if you have a UI label somewhere, and + +163 +00:07:50,804 --> 00:07:54,406 +you used a prefered body font, and the person cranks up their + +164 +00:07:54,408 --> 00:07:57,709 +size really big, cuz maybe their eyes are getting old, + +165 +00:07:57,711 --> 00:08:00,612 +age is getting up with, catching up with them Then + +166 +00:08:00,614 --> 00:08:03,949 +it's automatically going to change those for you. + +167 +00:08:03,951 --> 00:08:06,518 +So that's kind of cool feature. Okay, but + +168 +00:08:06,520 --> 00:08:08,820 +sometimes you might have something else that some other + +169 +00:08:08,822 --> 00:08:11,122 +part of the UI that depends on the size of font that you have + +170 +00:08:11,124 --> 00:08:13,825 +to adjust as well. And maybe I'll show that in a little bit + +171 +00:08:13,827 --> 00:08:18,864 +in my demo on Wednesday. Okay, now, what about broadcasting. + +172 +00:08:18,866 --> 00:08:21,500 +What if you want to be a radio station broadcaster? + +173 +00:08:21,502 --> 00:08:24,002 +How do youd do that? That's very easy too. + +174 +00:08:24,004 --> 00:08:26,238 +You just create one of these NSNotifications, + +175 +00:08:26,240 --> 00:08:29,307 +the same thing that is given to your closure when you're + +176 +00:08:29,309 --> 00:08:31,843 +a listener. You just create one of these things and + +177 +00:08:31,845 --> 00:08:34,513 +then you're gonna ask the NSNotification default center + +178 +00:08:34,515 --> 00:08:38,116 +to post that notification. Okay, and then it's going to + +179 +00:08:38,118 --> 00:08:40,585 +broadcast on that radio station. And the notification + +180 +00:08:40,587 --> 00:08:43,455 +of course has to have the name of the radio station. And + +181 +00:08:43,457 --> 00:08:44,823 +also, the object that is sending it. + +182 +00:08:44,825 --> 00:08:47,659 +That's usually gonna be self, right. Your post notification, + +183 +00:08:47,661 --> 00:08:49,427 +you're gonna usually have the self be the center. + +184 +00:08:49,429 --> 00:08:51,630 +And then here's that user info you get to provide, + +185 +00:08:51,632 --> 00:08:55,500 +okay. This is the information that's gonna go to people + +186 +00:08:55,502 --> 00:08:57,536 +who listen to your broadcast. Okay, + +187 +00:08:57,538 --> 00:08:58,904 +you just post this notification and + +188 +00:08:58,906 --> 00:09:02,007 +all the listeners will have their closures executed + +189 +00:09:02,009 --> 00:09:06,211 +with this notification object as the argument. Okay, + +190 +00:09:06,213 --> 00:09:09,180 +pretty simple, all right. Okay, so + +191 +00:09:09,182 --> 00:09:12,350 +that's it for notifications, now I'm gonna move on to, and + +192 +00:09:12,352 --> 00:09:14,152 +I'm gonna talk about notification more like in when + +193 +00:09:14,154 --> 00:09:15,554 +we talk about Cloud Kit a little later, + +194 +00:09:15,556 --> 00:09:17,589 +there's notifications involved there, so we'll talk about + +195 +00:09:17,591 --> 00:09:20,859 +this more that and then in the day we'll talk about this too + +196 +00:09:20,861 --> 00:09:22,460 +So now we're gonna do a little different topic here which + +197 +00:09:22,462 --> 00:09:26,698 +is the application lifecycle, okay. So this is what happens + +198 +00:09:26,700 --> 00:09:29,734 +to your application as it goes through its life, okay. + +199 +00:09:29,736 --> 00:09:32,737 +And it's really encapsulated in these boxes right here. + +200 +00:09:32,739 --> 00:09:37,642 +This green box right here is the kind of your application + +201 +00:09:37,644 --> 00:09:41,212 +when it's the user's focus of attention when they're running + +202 +00:09:41,214 --> 00:09:44,783 +your app. The blue box is your app is still around and + +203 +00:09:44,785 --> 00:09:47,352 +running but it's not the one the user's interacting with + +204 +00:09:47,354 --> 00:09:51,690 +right now. And then these other spaces are not that, + +205 +00:09:51,692 --> 00:09:54,859 +okay. It's not either of those cases. So let's look at this + +206 +00:09:54,861 --> 00:09:58,229 +green box this foreground box. Inside that green box there's + +207 +00:09:58,231 --> 00:10:00,932 +actually a little state here called inactive. + +208 +00:10:00,934 --> 00:10:05,036 +Okay that's when your app is running, it's the foreground, + +209 +00:10:05,038 --> 00:10:06,972 +but it's not receiving any UI events, okay. + +210 +00:10:06,974 --> 00:10:10,408 +So this is kind of like when it's just getting started up, + +211 +00:10:10,410 --> 00:10:13,411 +okay. And then it moves from there into this state + +212 +00:10:13,413 --> 00:10:17,215 +active where it's running and receiving events. Okay so + +213 +00:10:17,217 --> 00:10:19,751 +there are just two distinct states there, and you'll see + +214 +00:10:19,753 --> 00:10:23,855 +why we have those in a moment. And then down here, okay, + +215 +00:10:23,857 --> 00:10:26,891 +when you're in this background area, at the bottom, + +216 +00:10:26,893 --> 00:10:30,428 +your code might be running, for a short amount of time. + +217 +00:10:30,430 --> 00:10:33,565 +You don't usually run in the background for very long. Now, + +218 +00:10:33,567 --> 00:10:37,135 +there's a misconception that iOS, at least until recently, + +219 +00:10:37,137 --> 00:10:38,570 +is not a multitasking system. Because, + +220 +00:10:38,572 --> 00:10:41,306 +it seems like you only have one app running at a time. + +221 +00:10:41,308 --> 00:10:41,539 +in iOS nine, they introduced the ability to have two apps + +222 +00:10:41,541 --> 00:10:44,409 +Well of course, + +223 +00:10:44,411 --> 00:10:44,809 +running at the same time, + +224 +00:10:44,811 --> 00:10:47,979 +on the same screen at the same time. In on iPad, + +225 +00:10:47,981 --> 00:10:52,884 +side by side. But even before that, apps could run + +226 +00:10:52,886 --> 00:10:55,654 +at the same time. It just one would be or two or three would + +227 +00:10:55,656 --> 00:10:57,956 +be in the background and one would be in the foreground. + +228 +00:10:57,958 --> 00:11:00,759 +Of course, we know that iOS is just UNIX underneath and + +229 +00:11:00,761 --> 00:11:03,461 +UNIX is a complete multitasking operating + +230 +00:11:03,463 --> 00:11:03,528 +system so + +231 +00:11:03,530 --> 00:11:08,466 +The single tasking nature that it would appear that IOS had, + +232 +00:11:08,468 --> 00:11:12,504 +was more a UI decision for the user. The user could + +233 +00:11:12,506 --> 00:11:14,539 +concentrate on the one thing they're doing at the time and + +234 +00:11:14,541 --> 00:11:17,442 +I have a cluttered, trying to figure out what's going on, + +235 +00:11:17,444 --> 00:11:18,643 +which apps are running all the time. + +236 +00:11:18,645 --> 00:11:21,312 +So it's kind of a simplification of the UI. + +237 +00:11:21,314 --> 00:11:24,549 +Okay, but even then, apps were running in the background. + +238 +00:11:24,551 --> 00:11:27,152 +And we'll talk about why apps run in the back, + +239 +00:11:27,154 --> 00:11:30,388 +background and when and all that in a moment here, + +240 +00:11:30,390 --> 00:11:32,624 +okay. When you go down to the state + +241 +00:11:32,626 --> 00:11:36,127 +at the bottom, okay, your code, you are not running. + +242 +00:11:36,129 --> 00:11:39,664 +None of your, no code is being executed in your app at all. + +243 +00:11:39,666 --> 00:11:43,001 +You're in the suspended state. So your process still exists, + +244 +00:11:43,003 --> 00:11:44,369 +but it's not getting any cycles from the CPU. + +245 +00:11:44,371 --> 00:11:47,806 +It's just sitting there. So spend it. At any time in here, + +246 +00:11:47,808 --> 00:11:50,742 +you could be killed, okay, and you could be killed + +247 +00:11:50,744 --> 00:11:53,578 +without ever having a chance to run again. So + +248 +00:11:53,580 --> 00:11:54,279 +when you get into this state, + +249 +00:11:54,281 --> 00:11:57,949 +you wanna make sure you're ready to be killed, okay? + +250 +00:11:57,951 --> 00:12:00,585 +So that you don't have any data that's half written or + +251 +00:12:00,587 --> 00:12:03,555 +any kind of weird state, you have to be ready to be killed + +252 +00:12:03,557 --> 00:12:08,493 +down in this suspended state. Okay? And then of course, + +253 +00:12:08,495 --> 00:12:11,229 +y- you have the not running state at the top, and + +254 +00:12:11,231 --> 00:12:12,964 +how do we get out of this not running state? + +255 +00:12:12,966 --> 00:12:13,598 +So, the not running state, there's, + +256 +00:12:13,600 --> 00:12:16,534 +there's no process that's run in your app, and how do we get + +257 +00:12:16,536 --> 00:12:18,803 +out of that? Well, we getting out of it by launching. + +258 +00:12:18,805 --> 00:12:21,506 +And the launching process takes you from not running + +259 +00:12:21,508 --> 00:12:25,376 +into the foreground Thorough this inactive state and + +260 +00:12:25,378 --> 00:12:26,377 +then into active state. + +261 +00:12:26,379 --> 00:12:29,214 +Now it's also possible for you to be launched directly into + +262 +00:12:29,216 --> 00:12:32,517 +the background. Not really sure I am here but that's + +263 +00:12:32,519 --> 00:12:37,388 +possible as well. When you switch to another application. + +264 +00:12:37,390 --> 00:12:38,623 +So you are the primary application. + +265 +00:12:38,625 --> 00:12:40,592 +The user goes and switches to some other application. + +266 +00:12:40,594 --> 00:12:42,994 +Maybe by double clicking the home button or something like + +267 +00:12:42,996 --> 00:12:45,263 +that. Going back and picking something else. + +268 +00:12:45,265 --> 00:12:47,098 +What happens here is you go from the active state to + +269 +00:12:47,100 --> 00:12:50,568 +the inactive state and around to the background state. And + +270 +00:12:50,570 --> 00:12:53,905 +then after a little while, you moved to suspended, okay, + +271 +00:12:53,907 --> 00:12:56,374 +while this other app is running. Okay, so + +272 +00:12:56,376 --> 00:12:59,043 +if they go back to you, then you're gonna go back, okay, + +273 +00:12:59,045 --> 00:13:04,482 +the reverse here. Yes. I have mentioned this already. + +274 +00:13:04,484 --> 00:13:04,682 +When you're killed, + +275 +00:13:04,684 --> 00:13:06,217 +when you go through Suspended to Not running, + +276 +00:13:06,219 --> 00:13:09,387 +no code gets run in your app. So any preparation you have to + +277 +00:13:09,389 --> 00:13:11,990 +do for being killed has to happen before that. Now, + +278 +00:13:11,992 --> 00:13:14,692 +at each of these transitions happen, all these arrows, + +279 +00:13:14,694 --> 00:13:18,363 +okay, code gets executed in your application. Most notably + +280 +00:13:18,365 --> 00:13:21,366 +in your AppDelegate, okay? We know that AppDelegate file, + +281 +00:13:21,368 --> 00:13:24,469 +a file I always Move out of the way into supporting files + +282 +00:13:24,471 --> 00:13:28,339 +place that record data, and manage up the contexting was. + +283 +00:13:28,341 --> 00:13:30,875 +Okay, well, there's a bunch of methods in there since it is + +284 +00:13:30,877 --> 00:13:34,279 +the delegates UIApplication object not much methods + +285 +00:13:34,281 --> 00:13:36,481 +in there they're called as we transition through all + +286 +00:13:36,483 --> 00:13:38,783 +these states. So, we'll talk about those. So, + +287 +00:13:38,785 --> 00:13:42,453 +when you're going from not running to inactive, okay, or + +288 +00:13:42,455 --> 00:13:46,291 +this all time from not running into the background. + +289 +00:13:46,293 --> 00:13:49,060 +Okay, you could do this little path here + +290 +00:13:49,062 --> 00:13:53,198 +not running Inactive into the background. You get this + +291 +00:13:53,200 --> 00:13:55,066 +method right called in your AppDelegate called + +292 +00:13:55,068 --> 00:13:58,803 +ApplicationDidFinishLaunching- WithOption, okay, and + +293 +00:13:58,805 --> 00:14:01,840 +it's exactly what its sound. It's saying okay you have + +294 +00:14:01,842 --> 00:14:04,576 +launch, you're in the Inactive state, okay. + +295 +00:14:04,578 --> 00:14:08,079 +And here are some options and these options is a dictionary. + +296 +00:14:08,081 --> 00:14:09,380 +Okay and we'll talk about what's in the dictionary in + +297 +00:14:09,382 --> 00:14:12,951 +a second. You also are gonna get an NSNotification for + +298 +00:14:12,953 --> 00:14:15,820 +radio station broadcast on this radio station the + +299 +00:14:15,822 --> 00:14:19,057 +UIApplicationDidFinishLaunchi- ngNotification radio station. + +300 +00:14:19,059 --> 00:14:22,927 +And so if you observe on that you'll get your closer called + +301 +00:14:22,929 --> 00:14:26,397 +when the app reaches this inactive state right here. + +302 +00:14:26,399 --> 00:14:29,334 +Okay. Now, what's this dictionary all about right + +303 +00:14:29,336 --> 00:14:32,337 +here? Okay. So this dictionary is passed to you and + +304 +00:14:32,339 --> 00:14:34,939 +it tells you basically why you were launched. + +305 +00:14:34,941 --> 00:14:37,308 +Now, you always think of I get launched because someone + +306 +00:14:37,310 --> 00:14:40,311 +clicked on my icon. That's true. That's one way to get + +307 +00:14:40,313 --> 00:14:42,447 +launched but there's a lot other way to get launched. For + +308 +00:14:42,449 --> 00:14:45,950 +example, someone might want you to open URL. You might be + +309 +00:14:45,952 --> 00:14:50,421 +an app Like you're the Keynote app, okay, on iOS. And + +310 +00:14:50,423 --> 00:14:53,258 +you know how to open Keynote files. So when someone says, + +311 +00:14:53,260 --> 00:14:55,927 +I wanna open this Keynote file, the app is gonna launch + +312 +00:14:55,929 --> 00:14:59,264 +Keynote, okay. And so this is going to tell them + +313 +00:14:59,266 --> 00:15:03,601 +that that's why Keynote got launched. You might + +314 +00:15:03,603 --> 00:15:06,638 +do this because you enter a certain place in the world. + +315 +00:15:06,640 --> 00:15:06,871 +There's a way, + +316 +00:15:06,873 --> 00:15:09,607 +with core location which we haven't talked about, + +317 +00:15:09,609 --> 00:15:09,741 +to say hey, + +318 +00:15:09,743 --> 00:15:13,044 +if this person walks in this little area of the world, + +319 +00:15:13,046 --> 00:15:17,348 +these GPS coordinates, then wake my app up. Launch me, + +320 +00:15:17,350 --> 00:15:20,518 +because I want to do something when they walk into that area. + +321 +00:15:20,520 --> 00:15:23,154 +Okay? So you might get launched because of that. You + +322 +00:15:23,156 --> 00:15:25,957 +might be continuing activities started on another device. + +323 +00:15:25,959 --> 00:15:28,026 +How many people have used Da app + +324 +00:15:28,028 --> 00:15:30,828 +continuation where you start using an app like Safari or + +325 +00:15:30,830 --> 00:15:32,730 +something on your iPhone or something and + +326 +00:15:32,732 --> 00:15:34,632 +then you go over to your iPad and you just continue, + +327 +00:15:34,634 --> 00:15:36,401 +there's a little thing in the corner, okay, + +328 +00:15:36,403 --> 00:15:38,269 +only a couple of you are nodding your heads but + +329 +00:15:38,271 --> 00:15:40,438 +it's kind of a cool feature but if you go and + +330 +00:15:40,440 --> 00:15:43,074 +press that little continuation icon on your IOS and + +331 +00:15:43,076 --> 00:15:45,343 +of course it's going to launch you to continue what you were + +332 +00:15:45,345 --> 00:15:49,414 +doing on the device. Also a notification might have + +333 +00:15:49,416 --> 00:15:51,382 +arrived for you. Like push notification. + +334 +00:15:51,384 --> 00:15:54,652 +Who doesn't know what a push notification is? + +335 +00:15:54,654 --> 00:15:55,853 +Okay, so, everybody knows what that is. + +336 +00:15:55,855 --> 00:15:58,556 +It's little things that make the badges on your icon, + +337 +00:15:58,558 --> 00:16:01,059 +just basically when communication's coming from + +338 +00:16:01,061 --> 00:16:03,695 +servers out there in the world, things like that. + +339 +00:16:03,697 --> 00:16:07,065 +Well of course that might launch you. Maybe you have + +340 +00:16:07,067 --> 00:16:10,368 +some Bluetooth devi, Bluetooth device that is attached to + +341 +00:16:10,370 --> 00:16:13,771 +your computer and it wants to do something with your app, + +342 +00:16:13,773 --> 00:16:14,772 +it might launch your app to do that. + +343 +00:16:14,774 --> 00:16:17,408 +So you can see there's tons of examples and these, + +344 +00:16:17,410 --> 00:16:19,777 +this dictionary is gonna contain the information that + +345 +00:16:19,779 --> 00:16:23,915 +tells you For example, the URL it wants to open or that, + +346 +00:16:23,917 --> 00:16:26,718 +you know, that, you entered a certain place in the world or + +347 +00:16:26,720 --> 00:16:28,286 +things like that. So it's gonna give you information + +348 +00:16:28,288 --> 00:16:32,724 +about what happened that caused you to launch, okay. + +349 +00:16:33,893 --> 00:16:35,560 +One thing about this application to finish + +350 +00:16:35,562 --> 00:16:37,395 +launching with options. It used to be + +351 +00:16:37,397 --> 00:16:41,332 +that you actually built you UI here. Okay your primary UI. + +352 +00:16:41,334 --> 00:16:44,268 +Like a split view controller with a navigation controller + +353 +00:16:44,270 --> 00:16:46,471 +in the master with this view controller in it. And you + +354 +00:16:46,473 --> 00:16:50,942 +would actually build that in code inside of this. A method, + +355 +00:16:50,944 --> 00:16:54,145 +we no longer do that anymore, we use storyboards. But, + +356 +00:16:54,147 --> 00:16:55,913 +when you are doing your final project you are going to be + +357 +00:16:55,915 --> 00:16:59,417 +out searching on the internet for things and you are going + +358 +00:16:59,419 --> 00:17:01,152 +to find something and someone is going to say, Yeah, + +359 +00:17:01,154 --> 00:17:03,454 +you do this by putting code in your application to finish + +360 +00:17:03,456 --> 00:17:05,289 +launching with options. You create your split view there + +361 +00:17:05,291 --> 00:17:08,826 +and you set the delegates. Whoa don't do that That's old. + +362 +00:17:08,828 --> 00:17:12,063 +That's old IOS 7 kind of behavior but + +363 +00:17:12,065 --> 00:17:13,598 +you know sometimes on the internet when you're searching + +364 +00:17:13,600 --> 00:17:16,000 +you can't tell what's new and what's old. The good thing for + +365 +00:17:16,002 --> 00:17:19,370 +you guys is, if you search for Swift stuff, you're likely + +366 +00:17:19,372 --> 00:17:21,973 +gonna get new stuff. Swift's only been around since IOS 8 I + +367 +00:17:21,975 --> 00:17:27,045 +guess, maybe it was 9 I guess. I was eight, + +368 +00:17:27,047 --> 00:17:30,014 +I don't remember, whichever. So, so, it's new. + +369 +00:17:30,016 --> 00:17:32,717 +So you're not likely to see this stuff when you're looking + +370 +00:17:32,719 --> 00:17:37,255 +for Swift-based code. So that's good. Okay. All right, + +371 +00:17:37,257 --> 00:17:40,491 +so what about this transition right here? Okay. So you + +372 +00:17:40,493 --> 00:17:45,897 +are going out of the inactive of this, Active state into + +373 +00:17:45,899 --> 00:17:49,700 +inactive. So you were active, user was interacting with you. + +374 +00:17:49,702 --> 00:17:52,703 +And now you have been moved into the inactive state. + +375 +00:17:52,705 --> 00:17:55,239 +Now why is it important to know this state. + +376 +00:17:55,241 --> 00:18:01,245 +This I like to talk, about as the 'app is paused' state. + +377 +00:18:01,247 --> 00:18:04,082 +Okay? So for example, let's imagine a match in breakout. + +378 +00:18:04,084 --> 00:18:07,919 +Okay? This would be the you want to + +379 +00:18:07,921 --> 00:18:09,120 +pause the motion of the ball. + +380 +00:18:09,122 --> 00:18:12,757 +Remember it's Linear Velocity and Stop it. Okay, + +381 +00:18:12,759 --> 00:18:16,861 +in here. Now, you haven't gone to any of this other state, + +382 +00:18:16,863 --> 00:18:19,730 +you just move from Active to Inactive. Now, + +383 +00:18:19,732 --> 00:18:22,800 +why might you move from Active to Inactive? Well, you might + +384 +00:18:22,802 --> 00:18:25,670 +be in your way to being thrown in to the background and + +385 +00:18:25,672 --> 00:18:28,639 +then suspend it but maybe just a phone call came in., + +386 +00:18:28,641 --> 00:18:31,242 +Okay,if a phone call comes in you move to + +387 +00:18:31,244 --> 00:18:34,846 +the inactive foreground state. The phone call gets possessed. + +388 +00:18:34,848 --> 00:18:37,682 +When the person hangs up you go back to active. So, + +389 +00:18:37,684 --> 00:18:39,383 +if you had the bouncing ball in Breakout and + +390 +00:18:39,385 --> 00:18:41,719 +a phone call comes in, you wanna stop the ball. + +391 +00:18:41,721 --> 00:18:44,021 +When the call's over you wanna continue the ball right? + +392 +00:18:44,023 --> 00:18:46,757 +So this is the pause. Think about it as pause. + +393 +00:18:46,759 --> 00:18:50,027 +So, that's what you're gonna do in will resign active. And + +394 +00:18:50,029 --> 00:18:53,464 +again, there's a, radio station for it as well, okay, + +395 +00:18:53,466 --> 00:18:56,033 +as you can find out. The radio station is nice because + +396 +00:18:56,035 --> 00:18:59,137 +you can find out anywhere in your application if you just + +397 +00:18:59,139 --> 00:19:00,471 +went to this resign, okay? + +398 +00:19:00,473 --> 00:19:03,241 +You don't have to implement some method in app delegate, + +399 +00:19:03,243 --> 00:19:04,976 +you can find out anywhere in any view controller, + +400 +00:19:04,978 --> 00:19:10,915 +just sign up to listen to this radio station, okay. Now, + +401 +00:19:10,917 --> 00:19:13,050 +when you come back active again, okay, + +402 +00:19:13,052 --> 00:19:16,120 +maybe the phone call was over or maybe you're launching and + +403 +00:19:16,122 --> 00:19:19,457 +got to here. Okay or maybe you came out of the background. + +404 +00:19:19,459 --> 00:19:21,225 +For whatever reason when you come back here, + +405 +00:19:21,227 --> 00:19:21,926 +that's kind of the unpause. + +406 +00:19:21,928 --> 00:19:24,695 +Okay, that's where you're gonna put the ball back and + +407 +00:19:24,697 --> 00:19:29,000 +resume it's linear velocity to what it was. Okay? So this is + +408 +00:19:29,002 --> 00:19:32,069 +the pause and unpause capping between these two states right + +409 +00:19:32,071 --> 00:19:35,473 +here. And the great thing is, if you paused the ball and + +410 +00:19:35,475 --> 00:19:38,876 +you went to background, that's fine, it would be paused. And + +411 +00:19:38,878 --> 00:19:38,910 +when you come back, + +412 +00:19:38,912 --> 00:19:41,279 +whether it's come back from background or whatever reason, + +413 +00:19:41,281 --> 00:19:45,149 +you unpause and move the ball again. That's fine too. + +414 +00:19:45,151 --> 00:19:48,986 +All right? Now what about this state right here. Okay, + +415 +00:19:48,988 --> 00:19:51,189 +so here you were in the inactive state and + +416 +00:19:51,191 --> 00:19:53,090 +now you're moved into the background. Okay, + +417 +00:19:53,092 --> 00:19:55,826 +this is an important one right here, because when you move + +418 +00:19:55,828 --> 00:19:58,362 +into the background, you're only gonna get to run for + +419 +00:19:58,364 --> 00:20:00,398 +a short amount of time, about 30 seconds or so, + +420 +00:20:00,400 --> 00:20:02,767 +it's not actually guaranteed how long you get to run, + +421 +00:20:02,769 --> 00:20:06,304 +but practical matter, it's around 30 seconds. and + +422 +00:20:06,306 --> 00:20:08,606 +you'd better, in 30 seconds, you'd better hurry up, + +423 +00:20:08,608 --> 00:20:11,075 +and clean up. Because, after this, + +424 +00:20:11,077 --> 00:20:13,144 +you're probably gonna move down to the state suspended, + +425 +00:20:13,146 --> 00:20:16,714 +and then you can be killed at any time, okay? So, background + +426 +00:20:16,716 --> 00:20:19,550 +is really where you wanna batten down the hatches, okay? + +427 +00:20:19,552 --> 00:20:24,956 +Close files, you know, get rid of any stuff you're not using. + +428 +00:20:24,958 --> 00:20:28,926 +Things like that. Get your network state into the state + +429 +00:20:28,928 --> 00:20:31,162 +you want things like that because you might be, + +430 +00:20:31,164 --> 00:20:33,197 +this might be a prelude to being killed. + +431 +00:20:33,199 --> 00:20:34,098 +Maybe not but it might be so + +432 +00:20:34,100 --> 00:20:37,868 +you really wanna ask that here. Now it's possible to ask + +433 +00:20:37,870 --> 00:20:41,339 +the system for more time more if 30 seconds is not quite + +434 +00:20:41,341 --> 00:20:43,174 +enough, you can ask for a little bit more time but + +435 +00:20:43,176 --> 00:20:45,109 +eventually the system will get tired of you asking for + +436 +00:20:45,111 --> 00:20:48,613 +more time and they'll stop giving you more time. Okay. + +437 +00:20:48,615 --> 00:20:53,918 +Now, other applications, run in the background as well. + +438 +00:20:54,120 --> 00:20:56,988 +If not coming into this situation from here. + +439 +00:20:56,990 --> 00:20:59,890 +Whereas, user went to a different app or whatever. But + +440 +00:20:59,892 --> 00:21:02,026 +you can actually do things in the background. + +441 +00:21:02,028 --> 00:21:05,997 +And we'll talk about that in a second too. Okay. + +442 +00:21:05,999 --> 00:21:09,033 +Now when you come back okay, so you were in the background + +443 +00:21:09,035 --> 00:21:10,868 +okay or even suspended and then you went back + +444 +00:21:10,870 --> 00:21:13,070 +to the background and then the user made you active again. + +445 +00:21:13,072 --> 00:21:15,873 +Of course you come back up around here and you find out + +446 +00:21:15,875 --> 00:21:18,476 +here that application will enter foreground. You see + +447 +00:21:18,478 --> 00:21:20,945 +how you're coming out of the background into the green box + +448 +00:21:20,947 --> 00:21:24,382 +foreground there. Will tell you that you're back alive. + +449 +00:21:24,384 --> 00:21:26,150 +And now you can un-batten down the hatchets. + +450 +00:21:26,152 --> 00:21:29,453 +Undo what you did when you got into the background here. + +451 +00:21:29,455 --> 00:21:31,722 +You can open things back up. + +452 +00:21:32,258 --> 00:21:36,627 +All right, now, what other things can you do in + +453 +00:21:36,629 --> 00:21:40,064 +the AppDelegate besides these lifecycle methods? Tons of + +454 +00:21:40,066 --> 00:21:43,734 +things, okay. So not only can you handle push notifications + +455 +00:21:43,736 --> 00:21:46,771 +here, okay. You also have a local notification, which + +456 +00:21:46,773 --> 00:21:50,541 +are notification that you set to go up at a certain time. + +457 +00:21:50,543 --> 00:21:54,445 +Like reminders, okay, it's at 10:00pm every day, + +458 +00:21:54,447 --> 00:21:57,581 +have this local notification go up and wake my app up, and + +459 +00:21:57,583 --> 00:22:03,354 +go do something. Well, all that handled through the Also, + +460 +00:22:03,356 --> 00:22:05,589 +data protection, okay. + +461 +00:22:05,591 --> 00:22:09,593 +When your, when your app or your device is locked, + +462 +00:22:09,595 --> 00:22:12,663 +then a lot of the data, pretty much by default, + +463 +00:22:12,665 --> 00:22:15,166 +all of the data on your phone is encrypted. Okay. + +464 +00:22:15,168 --> 00:22:18,302 +That's why a locked phone, no one can get in there to your + +465 +00:22:18,304 --> 00:22:20,671 +data cuz it's encrypted, okay? And so + +466 +00:22:20,673 --> 00:22:24,208 +all the locking and unlocking and giving you access of files + +467 +00:22:24,210 --> 00:22:26,677 +where they're not encrypted when you're unlocked and + +468 +00:22:26,679 --> 00:22:27,611 +encrypted when they're locked, + +469 +00:22:27,613 --> 00:22:31,982 +that's all the AppDelegate. The AppDelegate also would get + +470 +00:22:31,984 --> 00:22:33,351 +called if you were already running and + +471 +00:22:33,353 --> 00:22:35,386 +someone said open this URL, like your keynote, + +472 +00:22:35,388 --> 00:22:38,589 +and someone said open this keynote file. You can also do + +473 +00:22:38,591 --> 00:22:41,359 +what's called background fetching which is kinda cool. + +474 +00:22:41,361 --> 00:22:41,592 +Let's say your some + +475 +00:22:41,594 --> 00:22:43,260 +social media app or something like that. + +476 +00:22:43,262 --> 00:22:47,832 +A news app and you want to kinda through out the day, + +477 +00:22:47,834 --> 00:22:49,433 +go often fetch the latest news. + +478 +00:22:49,435 --> 00:22:51,902 +So when the app runs you got the latest news right there. + +479 +00:22:51,904 --> 00:22:54,972 +You don't have to go fetch on the network at that time. And + +480 +00:22:54,974 --> 00:22:56,207 +you are actually allowed to do that, + +481 +00:22:56,209 --> 00:22:59,677 +so this background fetching Let your app launch and + +482 +00:22:59,679 --> 00:23:02,713 +run in the background for the little while again not too + +483 +00:23:02,715 --> 00:23:05,783 +long okay this is another one too many apps stealing cycles + +484 +00:23:05,785 --> 00:23:08,753 +from the foreground app but it will run in the background and + +485 +00:23:08,755 --> 00:23:10,020 +you can go do some network activity. + +486 +00:23:10,022 --> 00:23:10,855 +Pull down your data or whatever and + +487 +00:23:10,857 --> 00:23:14,525 +then go back to sleep and the system manages that and + +488 +00:23:14,527 --> 00:23:15,659 +you can go look at the documentation for + +489 +00:23:15,661 --> 00:23:19,597 +UI application to find out how you set this up. You have to + +490 +00:23:19,599 --> 00:23:22,533 +enable something in the capabilities of your app. + +491 +00:23:22,535 --> 00:23:22,900 +You set this up and + +492 +00:23:22,902 --> 00:23:25,369 +you can say kinda how often you wanna be woken up and + +493 +00:23:25,371 --> 00:23:28,873 +all those kinda things. If you abuse this, of course this so + +494 +00:23:28,875 --> 00:23:32,243 +we'll stop waking you up in the background. Other Other + +495 +00:23:32,245 --> 00:23:34,245 +reasons that you might wake up in the background. + +496 +00:23:34,247 --> 00:23:38,416 +You might be a VOIP app, right. A voice over IP app and + +497 +00:23:38,418 --> 00:23:41,218 +so you're using some other application in the foreground, + +498 +00:23:41,220 --> 00:23:43,954 +but you're talking on over VOIP to someone else. + +499 +00:23:43,956 --> 00:23:45,956 +Or you're a music playing app, okay. + +500 +00:23:45,958 --> 00:23:47,324 +And the person's got their headphones on, they're + +501 +00:23:47,326 --> 00:23:49,693 +listening to your music while they're using some other app. + +502 +00:23:49,695 --> 00:23:51,529 +Of course you're of course running in the background in + +503 +00:23:51,531 --> 00:23:53,864 +that case. So there are a lot of cases where you can run in + +504 +00:23:53,866 --> 00:23:56,100 +the background and you can look it all this up in your UI + +505 +00:23:56,102 --> 00:23:59,503 +application. Unfortunately, again from time constraints, + +506 +00:23:59,505 --> 00:24:00,538 +I don't have time to go thru and + +507 +00:24:00,540 --> 00:24:03,674 +show you all the Cool thing to know in the background but + +508 +00:24:03,676 --> 00:24:04,475 +these are some of them, and + +509 +00:24:04,477 --> 00:24:08,012 +almost all of this stuff happens with your AppDelegate. + +510 +00:24:08,014 --> 00:24:10,448 +Okay the methods in the AppDelegate. + +511 +00:24:11,117 --> 00:24:14,518 +All right, let's talk about UIApplication. The actual + +512 +00:24:14,520 --> 00:24:16,754 +object UIApplication is only one instance, + +513 +00:24:16,756 --> 00:24:19,957 +obviously in your app. You get it by calling this method + +514 +00:24:19,959 --> 00:24:24,328 +UIApplication.sharedapplica- tion Right there. Okay. + +515 +00:24:24,330 --> 00:24:28,666 +And it manages all the global behavior in your app. Mostly + +516 +00:24:28,668 --> 00:24:31,302 +it delegates things to its delegate, the app delegate, + +517 +00:24:31,304 --> 00:24:34,071 +so that's good, that's why we see so much behavior there. + +518 +00:24:34,073 --> 00:24:36,841 +But it does have some useful functionality of it's own. + +519 +00:24:36,843 --> 00:24:39,376 +For example, it has a method called openURL. + +520 +00:24:39,378 --> 00:24:41,645 +You saw this in your smashtag. Right, + +521 +00:24:41,647 --> 00:24:44,181 +this is how you could click on a URL and open it up. + +522 +00:24:44,183 --> 00:24:47,618 +You call this application method openURL okay. + +523 +00:24:47,620 --> 00:24:51,121 +You can register here for scheduling these + +524 +00:24:51,123 --> 00:24:53,591 +notifications. These local notifications, right, those + +525 +00:24:53,593 --> 00:24:56,427 +things I was telling you wake up every day at 10 o'clock and + +526 +00:24:56,429 --> 00:24:59,296 +run my app kind of things. You actually register and + +527 +00:24:59,298 --> 00:25:02,800 +schedule them here in UIApplication If + +528 +00:25:02,802 --> 00:25:05,202 +you are doing the background fetching thing I talked about. + +529 +00:25:05,204 --> 00:25:08,672 +You can set the minimum fetch interval. Okay, + +530 +00:25:08,674 --> 00:25:09,607 +so how often your background, + +531 +00:25:09,609 --> 00:25:12,243 +things gonna open up in the background in run? Here is + +532 +00:25:12,245 --> 00:25:15,713 +how you ask for more time if you're in the background. + +533 +00:25:15,715 --> 00:25:20,251 +Background task with expiration handler. Okay, + +534 +00:25:20,253 --> 00:25:23,153 +there's a little spinning wheel on the upper left + +535 +00:25:23,155 --> 00:25:26,023 +corner in the status bar of your iOS device. + +536 +00:25:26,025 --> 00:25:26,624 +I'm sure you've seen it, right, + +537 +00:25:26,626 --> 00:25:29,159 +that's supposed to represent network activity. You can turn + +538 +00:25:29,161 --> 00:25:32,563 +that on and off with this bool right here in UIApplication. + +539 +00:25:32,565 --> 00:25:34,798 +networkActivityIndicatorVis- ible equals true and + +540 +00:25:34,800 --> 00:25:38,702 +it'll on start spinning. Say false, it'll turn off. + +541 +00:25:38,704 --> 00:25:41,539 +Okay, and you generally should do this anytime you're + +542 +00:25:41,541 --> 00:25:45,009 +doing any network activity so that the user knows, app is + +543 +00:25:45,011 --> 00:25:49,046 +accessing the network right now. You can also find out + +544 +00:25:49,048 --> 00:25:51,582 +a lot of things, like remember that content sides category, + +545 +00:25:51,584 --> 00:25:54,051 +the fonts, big fonts on, you can find that out, + +546 +00:25:54,053 --> 00:25:55,786 +you can poll it, of course, you could also listen + +547 +00:25:55,788 --> 00:25:57,821 +to the radio station that tells you when it changes, but + +548 +00:25:57,823 --> 00:26:00,224 +you can poll it. You can also find out how much time + +549 +00:26:00,226 --> 00:26:03,160 +you've got remaining until you're gonna be suspended + +550 +00:26:03,162 --> 00:26:06,497 +from the background state. And you can even find out + +551 +00:26:06,499 --> 00:26:07,998 +what state you're in. Am I in the foreground? + +552 +00:26:08,000 --> 00:26:11,835 +Am I in the background etc. With this guy right there. + +553 +00:26:12,305 --> 00:26:15,639 +Okay? Now let's talk about Info.plist. + +554 +00:26:15,641 --> 00:26:16,941 +We've actually seen Info.plist. + +555 +00:26:16,943 --> 00:26:21,345 +Remember, that's where we went when we tried to access URLs, + +556 +00:26:21,347 --> 00:26:23,948 +and they were HTTP not HTTPS, right? And + +557 +00:26:23,950 --> 00:26:27,384 +we had to go in here and add something to our Info.plist + +558 +00:26:27,386 --> 00:26:32,957 +that allowed us to kind of unsecurely access URLs and + +559 +00:26:32,959 --> 00:26:35,593 +in general Info.plist is for things like that. + +560 +00:26:35,595 --> 00:26:38,262 +Little settings that you're gonna set to do things like + +561 +00:26:38,264 --> 00:26:41,599 +that. You can see that there's an, kind of a property list + +562 +00:26:41,601 --> 00:26:45,536 +editor right here. Lets you go through and edit values and + +563 +00:26:45,538 --> 00:26:48,973 +even you know, if the values are arrays okay, you can + +564 +00:26:48,975 --> 00:26:52,409 +edit that in there. You can also right-click on it and + +565 +00:26:52,411 --> 00:26:56,246 +change it to be an XML view, okay? I don't really recommend + +566 +00:26:56,248 --> 00:26:58,849 +this, cuz it's easy to make a syntax error in here, and + +567 +00:26:58,851 --> 00:27:00,050 +now your Info.plist can't be read. + +568 +00:27:00,052 --> 00:27:02,720 +So I'd stick with the other view. But actually, most of + +569 +00:27:02,722 --> 00:27:06,924 +the things in Info.plist you set In the general settings of + +570 +00:27:06,926 --> 00:27:09,994 +your project. Right? All these places where we said + +571 +00:27:09,996 --> 00:27:13,931 +things like, portrait upside down or landscape left. + +572 +00:27:13,933 --> 00:27:14,431 +Which one of those are allowed? + +573 +00:27:14,433 --> 00:27:17,301 +Those are info.p list things but we edit them here. + +574 +00:27:17,303 --> 00:27:21,805 +It's just nicer. And most of the common ones we can find in + +575 +00:27:22,241 --> 00:27:27,678 +here. Okay? Now, in addition to all, all the settings there + +576 +00:27:27,680 --> 00:27:31,982 +there's also some capabilities in your app that you have to + +577 +00:27:31,984 --> 00:27:35,719 +explicitly enable if you wanna use them, okay? And you do + +578 +00:27:35,721 --> 00:27:38,622 +this in the Capabilities tab in your Project Setting, + +579 +00:27:38,624 --> 00:27:39,690 +it looks like this. Okay. + +580 +00:27:39,692 --> 00:27:41,425 +This list is always always changing. But + +581 +00:27:41,427 --> 00:27:43,961 +you can see a lot of cool features in here like iCloud, + +582 +00:27:43,963 --> 00:27:47,031 +wich I'm gonna talk about a little later in this lecture, + +583 +00:27:47,033 --> 00:27:47,598 +and the Game Centre, + +584 +00:27:47,600 --> 00:27:51,201 +Apple Pay, here the background fetching thing, + +585 +00:27:51,203 --> 00:27:55,873 +right here, Data Protection down here, Home Kit and + +586 +00:27:55,875 --> 00:27:58,909 +Health Kit down at the bottom. If you wanna use any of these, + +587 +00:27:58,911 --> 00:28:01,812 +you have to turn it on by just going to this capabilities + +588 +00:28:01,814 --> 00:28:04,181 +tab in your project settings. And just clicking this + +589 +00:28:04,183 --> 00:28:07,184 +from off to on. And when you click it to on, there's going + +590 +00:28:07,186 --> 00:28:08,986 +to be various settings for that thing. Okay and + +591 +00:28:08,988 --> 00:28:12,222 +we'll see this all in detail when we do Cloud Kit. Okay, + +592 +00:28:12,224 --> 00:28:15,092 +you can also see from this how much stuff I just can't cover + +593 +00:28:15,094 --> 00:28:17,094 +in this class. In fact, of this whole list. + +594 +00:28:17,096 --> 00:28:19,863 +Only thing I'm gonna cover is the first one, I cloud. + +595 +00:28:19,865 --> 00:28:22,499 +Okay? The rest of the stuff, I just don't have time to get to + +596 +00:28:22,501 --> 00:28:25,803 +it all. When you go start looking through the doc and + +597 +00:28:25,805 --> 00:28:27,371 +you start looking at some of the things you might do, + +598 +00:28:27,373 --> 00:28:29,940 +you can know that you have to go here to turn things on. + +599 +00:28:29,942 --> 00:28:33,877 +Okay? All right, so + +600 +00:28:33,879 --> 00:28:36,580 +that's pretty much it for your application lifestyle, + +601 +00:28:36,582 --> 00:28:40,050 +life cycle, and kind of overall settings in your app. + +602 +00:28:40,052 --> 00:28:44,722 +The next topic I'm gonna do is alerts and action sheets okay. + +603 +00:28:44,724 --> 00:28:46,056 +So these are the pop up and + +604 +00:28:46,058 --> 00:28:49,793 +ask the user something UI okay. And they're very, + +605 +00:28:49,795 --> 00:28:54,965 +very similar the API for them is almost identical okay but + +606 +00:28:54,967 --> 00:28:56,066 +their UI is slightly different so + +607 +00:28:56,068 --> 00:28:58,702 +let's take a look at these alerts and action sheets. So + +608 +00:28:58,704 --> 00:29:01,138 +alerts, always pop up in the middle of the screen. + +609 +00:29:01,140 --> 00:29:03,474 +They grey out everything else behind it. Okay. + +610 +00:29:03,476 --> 00:29:05,476 +On this little screen. Both an iPad and iPhone. + +611 +00:29:05,478 --> 00:29:10,748 +*swallow* And, it usually asks a question that has + +612 +00:29:10,750 --> 00:29:11,582 +usually one or two answers. + +613 +00:29:11,584 --> 00:29:15,219 +Either you just click 'okay' or maybe 'okay, cancel' or + +614 +00:29:15,221 --> 00:29:19,156 +'yes, no'. Possibly a third answer. But usually it's only + +615 +00:29:19,158 --> 00:29:23,494 +two. Answers. This thing is very modal, + +616 +00:29:23,496 --> 00:29:24,995 +it kind of takes over your whole UI and + +617 +00:29:24,997 --> 00:29:26,430 +just puts up this little box, so you know, + +618 +00:29:26,432 --> 00:29:29,066 +you don't wanna use it unless you really can't proceed + +619 +00:29:29,068 --> 00:29:33,704 +without the user acknowledging this information or whatever. + +620 +00:29:33,706 --> 00:29:36,206 +Usually it's used when there are asynchronous problems, + +621 +00:29:36,208 --> 00:29:40,878 +some network connection fails. There's no place in the UI to + +622 +00:29:40,880 --> 00:29:43,347 +tell them that, so you kinda have to Take over for + +623 +00:29:43,349 --> 00:29:47,017 +a moment and say the network connection failed click OK or + +624 +00:29:47,019 --> 00:29:51,288 +click here to retry or whatever. Okay, this alerts + +625 +00:29:51,290 --> 00:29:56,293 +can have text fields in it as well. Okay, and the condition + +626 +00:29:56,295 --> 00:29:57,895 +just OK or cancel or whatever you cannot type full. + +627 +00:29:57,897 --> 00:30:01,899 +So you could use it for you know, access tonight. Enter + +628 +00:30:01,901 --> 00:30:05,903 +password Okay, you can use it for things like that. Okay? + +629 +00:30:05,905 --> 00:30:10,674 +I wouldn't use it as a general text of obtaining UI, however. + +630 +00:30:10,676 --> 00:30:13,677 +Okay? Again, it's only for exceptional circumstances. + +631 +00:30:13,679 --> 00:30:16,747 +Now an action sheet is very similar to an alert, but + +632 +00:30:16,749 --> 00:30:19,183 +it has more than two choices, usually three or + +633 +00:30:19,185 --> 00:30:22,886 +four choices. Okay? Instead of appearing in the middle, + +634 +00:30:22,888 --> 00:30:25,689 +it slides up from the bottom, on an iPhone, or + +635 +00:30:25,691 --> 00:30:30,994 +it appears in a popover on an iPad, okay? And you kind of + +636 +00:30:30,996 --> 00:30:34,798 +would think of, action sheet as a branching decision UI. + +637 +00:30:34,800 --> 00:30:37,968 +Okay, the user has reached a place in there Point in their + +638 +00:30:37,970 --> 00:30:41,004 +use of the UI where they have to branch and go do a certain + +639 +00:30:41,006 --> 00:30:42,673 +task, and go a different direction, they have two, + +640 +00:30:42,675 --> 00:30:46,877 +or three, or four different ways that they can go. Okay? + +641 +00:30:46,879 --> 00:30:50,047 +Now you've seen all these UI, these things in your app, + +642 +00:30:50,049 --> 00:30:51,515 +so I don't want to go too much into it, + +643 +00:30:51,517 --> 00:30:54,418 +but let's look a little bit about how we + +644 +00:30:54,420 --> 00:30:57,621 +do the code behind it. So Here is what they look like. + +645 +00:30:57,623 --> 00:30:59,923 +An action sheet comes up from the bottom. right. + +646 +00:30:59,925 --> 00:31:03,560 +It's got a tile right here and then also a little commentary + +647 +00:31:03,562 --> 00:31:06,997 +in there some explanation. And then it's got the buttons. + +648 +00:31:06,999 --> 00:31:11,602 +And alert is, comes up in the middle of the screen. + +649 +00:31:11,604 --> 00:31:13,670 +It's, you got one or two buttons usually and + +650 +00:31:13,672 --> 00:31:16,974 +possibly. Text, so here for example I've got + +651 +00:31:16,976 --> 00:31:21,178 +a Login Required to control my Cassini I guess here and + +652 +00:31:21,180 --> 00:31:23,881 +you got to type your guided system password to + +653 +00:31:23,883 --> 00:31:25,883 +be able to get control of Cassini. + +654 +00:31:25,885 --> 00:31:28,485 +While over in the Action Sheet I'm kind of + +655 +00:31:28,487 --> 00:31:31,288 +Cassini wants to go somewhere and we're picking a branch in + +656 +00:31:31,290 --> 00:31:33,190 +decision whether we're gonna Orbit Saturn or + +657 +00:31:33,192 --> 00:31:36,293 +E=xplore Titan, get a Closeup of the Sun. Or just cancel + +658 +00:31:36,295 --> 00:31:40,264 +that branching decision. Okay? So, how's the code for + +659 +00:31:40,266 --> 00:31:45,535 +this look? Well these things, like action sheet, are just + +660 +00:31:45,537 --> 00:31:48,572 +UI view controllers. Okay? They're presented motilly, + +661 +00:31:48,574 --> 00:31:50,974 +they just instead of taking over the whole screen, + +662 +00:31:50,976 --> 00:31:52,342 +they just get drawn like this, or + +663 +00:31:52,344 --> 00:31:53,777 +as a little square in the middle. + +664 +00:31:53,779 --> 00:31:55,379 +But they're basically just UI view controllers + +665 +00:31:55,381 --> 00:31:57,681 +presented motilly. I haven't really talked about motile + +666 +00:31:57,683 --> 00:32:00,484 +presentation. I hope to get that on Wednesday, but + +667 +00:32:00,486 --> 00:32:03,520 +modal just means you can't do anything else in that app + +668 +00:32:03,522 --> 00:32:07,391 +until you deal with this view controller. K, so these + +669 +00:32:07,393 --> 00:32:09,293 +are modal view controllers so you create them but + +670 +00:32:09,295 --> 00:32:11,828 +they are initially initialized to UI alert controller, + +671 +00:32:11,830 --> 00:32:14,131 +gonna create you one of these UI view controllers. + +672 +00:32:14,133 --> 00:32:16,600 +It's a sub class of UI view controller. All you need to + +673 +00:32:16,602 --> 00:32:19,770 +specify is this title right here like Redeploy Cassini. + +674 +00:32:19,772 --> 00:32:21,972 +And the message that goes in here + +675 +00:32:21,974 --> 00:32:24,107 +Issue commands to Cassini's guidance system. + +676 +00:32:24,109 --> 00:32:26,176 +Right here. And then, the style you want, + +677 +00:32:26,178 --> 00:32:29,646 +either action sheet or alert. Okay, so that's it, + +678 +00:32:29,648 --> 00:32:32,182 +that's how you create one of these view controllers. + +679 +00:32:32,184 --> 00:32:34,318 +The next step is we're gonna configure it and + +680 +00:32:34,320 --> 00:32:35,919 +then we're going to present it modally. + +681 +00:32:35,921 --> 00:32:38,355 +So let's do the configuration part. + +682 +00:32:38,357 --> 00:32:42,726 +Obviously configuring it, we need to add actions to it, + +683 +00:32:42,728 --> 00:32:45,295 +okay, these various buttons and we do that by sending + +684 +00:32:45,297 --> 00:32:50,033 +the method addAction, okay, to the alert and the addAction + +685 +00:32:50,035 --> 00:32:54,805 +takes one argument which is a UIAlertAction, okay. + +686 +00:32:54,807 --> 00:32:57,341 +They UIAlertAction has the following + +687 +00:32:57,343 --> 00:33:00,110 +initializer arguments The title that's gonna be + +688 +00:33:00,112 --> 00:33:02,713 +the title on the button okay like Orbit Saturn or + +689 +00:33:02,715 --> 00:33:05,449 +Explore Titan whatever. The style we'll talk about what + +690 +00:33:05,451 --> 00:33:08,118 +that style is in a second and then a handler and + +691 +00:33:08,120 --> 00:33:11,054 +this is just a closure that's gonna get executed when + +692 +00:33:11,056 --> 00:33:15,392 +this button gets pressed. Got it? So could be simpler. Okay + +693 +00:33:15,394 --> 00:33:18,662 +that's all there is. So let's look at some examples of this. + +694 +00:33:18,664 --> 00:33:19,997 +Here's orbit Saturn right here. + +695 +00:33:19,999 --> 00:33:23,433 +The title is Orbit Saturn, the style is the default style, + +696 +00:33:23,435 --> 00:33:26,370 +orbit Saturn explore Titan or default style buttons. We'll + +697 +00:33:26,372 --> 00:33:29,373 +talk about the other styles in a second. And in the closure, + +698 +00:33:29,375 --> 00:33:32,209 +obviously we're going to go into orbit around Saturn. + +699 +00:33:32,211 --> 00:33:33,010 +That's what we're going to do and + +700 +00:33:33,012 --> 00:33:36,446 +we'll do whatever code is necessary to do that there. + +701 +00:33:36,448 --> 00:33:38,048 +Okay, so here is Explore TItan, + +702 +00:33:38,050 --> 00:33:42,686 +almost exactly the same. Okay. Just that the, closure here is + +703 +00:33:42,688 --> 00:33:45,789 +a little different. Notice this closure says, okay, + +704 +00:33:45,791 --> 00:33:48,759 +if I'm going to Explorer TItan that's not part of Cassini's + +705 +00:33:48,761 --> 00:33:50,427 +mission, then, so I'm going to log, + +706 +00:33:50,429 --> 00:33:53,230 +make the person log in. Okay you can send him to Saturn, + +707 +00:33:53,232 --> 00:33:56,299 +send Cassini to Saturn evidently without a password. + +708 +00:33:56,301 --> 00:33:58,668 +But you need to enter a password for Titan. + +709 +00:33:58,670 --> 00:34:01,705 +So just has a little different action there, that's all. + +710 +00:34:01,707 --> 00:34:06,243 +Okay and these are both normal default style buttons. + +711 +00:34:06,245 --> 00:34:09,713 +Now let's take a look at closing, closer, go closeup to + +712 +00:34:09,715 --> 00:34:12,482 +the sun here, okay. Closeup to the sun's a little different. + +713 +00:34:12,484 --> 00:34:17,821 +Its style is not default, it's Destructive. So if you have a, + +714 +00:34:17,823 --> 00:34:20,924 +action sheet button that is of style of destructive, + +715 +00:34:20,926 --> 00:34:24,227 +it's gonna appear red, okay. Now you should always + +716 +00:34:24,229 --> 00:34:27,064 +pick destructive if the thing the users gonna do with this + +717 +00:34:27,066 --> 00:34:30,167 +button is going to do something permanent like + +718 +00:34:30,169 --> 00:34:30,500 +delete something, + +719 +00:34:30,502 --> 00:34:33,303 +delete an entry from a database that can't be undone, + +720 +00:34:33,305 --> 00:34:36,606 +or something like that. Okay so that is a destructive here. + +721 +00:34:36,608 --> 00:34:39,743 +A close up of the sun is probably destroy Cassini so + +722 +00:34:39,745 --> 00:34:41,978 +we made that destructive, alright but + +723 +00:34:41,980 --> 00:34:46,583 +otherwise it is still going to perform this action. Okay, + +724 +00:34:46,585 --> 00:34:50,020 +and what about cancel so cancel you notice it looks + +725 +00:34:50,022 --> 00:34:52,756 +a little different it is kind of separated. You see that? + +726 +00:34:52,758 --> 00:34:57,360 +Otherwise it looks the same. Maybe the font might be bold? + +727 +00:34:57,362 --> 00:35:01,331 +Hard to tell there, I think so. But otherwise, it's just + +728 +00:35:01,333 --> 00:35:03,934 +a normal button, okay? But it's of style cancel. + +729 +00:35:03,936 --> 00:35:06,369 +When we get to iPad, you're gonna see why it's very + +730 +00:35:06,371 --> 00:35:09,706 +important that we make our Cancel button be style. Cancel + +731 +00:35:09,708 --> 00:35:14,478 +be a different style than the other thing. Okay. So you add + +732 +00:35:14,480 --> 00:35:18,215 +all your actions there to do all the things you want to do. + +733 +00:35:18,217 --> 00:35:21,351 +And then you simply call this view controller method, + +734 +00:35:21,353 --> 00:35:23,854 +present view controller. Present view controller is + +735 +00:35:23,856 --> 00:35:27,757 +the Normal modal presentation method in view controller. + +736 +00:35:27,759 --> 00:35:30,594 +When I get talk, give you the lecture on mobile view + +737 +00:35:30,596 --> 00:35:32,529 +controllers, this is the method I'm gonna talk about. + +738 +00:35:32,531 --> 00:35:35,198 +You call this method, it takes a view controller, that's what + +739 +00:35:35,200 --> 00:35:38,335 +an alert is, right? Alert is alert controller which is + +740 +00:35:38,337 --> 00:35:39,202 +subclass UIController. + +741 +00:35:39,204 --> 00:35:42,639 +Takes one of these and it presents is modally. Okay, + +742 +00:35:42,641 --> 00:35:46,276 +this is whether it's going to animate the presentation. And + +743 +00:35:46,278 --> 00:35:48,044 +this is just a completion handler, they call it, + +744 +00:35:48,046 --> 00:35:51,381 +it gets called when it has finished presenting it. + +745 +00:35:51,383 --> 00:35:54,284 +Now when it goes away but when it finishes presenting so it's + +746 +00:35:54,286 --> 00:35:57,154 +on screen. Okay, we almost never use that, by the way. + +747 +00:35:57,156 --> 00:36:00,223 +All right, so the view controller, you do that, okay. + +748 +00:36:00,225 --> 00:36:03,426 +It puts the thing up, now when these buttons get pressed, + +749 +00:36:03,428 --> 00:36:05,262 +their closures get called. Okay, + +750 +00:36:05,264 --> 00:36:09,466 +when cancel gets pressed, it goes away, it dismisses. + +751 +00:36:10,102 --> 00:36:13,637 +That's it, that's how you use the Action sheet. Alright, + +752 +00:36:13,639 --> 00:36:18,608 +now, let's talk a little bit about iPad, okay. Because, + +753 +00:36:18,610 --> 00:36:22,679 +an iPad, this thing would look ridiculous if it came up from + +754 +00:36:22,681 --> 00:36:25,115 +the bottom. Either it would just be a tiny thing here, or + +755 +00:36:25,117 --> 00:36:28,151 +if it was as wide as the whole screen It will be gigantic, + +756 +00:36:28,153 --> 00:36:32,556 +okay? So we don't have these things come up from the bottom + +757 +00:36:32,558 --> 00:36:37,093 +on an iPad, instead we have them come up as pop-overs, + +758 +00:36:37,095 --> 00:36:40,197 +okay. See how this is the same thing, but it's over pop-over. + +759 +00:36:40,199 --> 00:36:43,733 +Notice, no cancel button, okay? Why do we + +760 +00:36:43,735 --> 00:36:45,302 +have no cancel button on iPad? + +761 +00:36:45,304 --> 00:36:48,572 +Because when a pop-over comes up, you click anywhere else, + +762 +00:36:48,574 --> 00:36:53,176 +it dismisses it. That's just like hitting cancel, okay. + +763 +00:36:53,178 --> 00:36:58,181 +In fact your cancel closure will get there, okay. So what + +764 +00:36:58,183 --> 00:37:03,353 +do we need to do to make this appear in a pop over, on iPad, + +765 +00:37:03,355 --> 00:37:05,522 +okay. Well we do need to do a little bit different code. + +766 +00:37:05,524 --> 00:37:08,024 +So here's our code from the iPhone. Okay. + +767 +00:37:08,026 --> 00:37:11,628 +First we're gonna add a little thing in here, which is, + +768 +00:37:11,630 --> 00:37:12,162 +we're gonna set the, + +769 +00:37:12,164 --> 00:37:16,700 +a View Controller's modal Presentation Style to Popover. + +770 +00:37:16,702 --> 00:37:18,368 +Okay, that says present this modally, + +771 +00:37:18,370 --> 00:37:22,639 +but in a Popover style, instead of up from the bottom + +772 +00:37:22,641 --> 00:37:27,177 +there. Okay? Then we just need to get the popover + +773 +00:37:27,179 --> 00:37:30,447 +Presentation Controller, which is just It's a class. + +774 +00:37:30,449 --> 00:37:31,681 +We're not gonna talk too much about it, + +775 +00:37:31,683 --> 00:37:34,718 +but it's the thing that controls presentation. + +776 +00:37:34,720 --> 00:37:37,554 +Okay? All view controllers, when they're presented, + +777 +00:37:37,556 --> 00:37:39,856 +have a presentation controller that presents them. + +778 +00:37:39,858 --> 00:37:42,559 +Well, pop-over ones have one called pop-over presentation + +779 +00:37:42,561 --> 00:37:45,295 +controller. You're just gonna get this thing if you look for + +780 +00:37:45,297 --> 00:37:47,364 +the UI for a pop-over presentation controller, + +781 +00:37:47,366 --> 00:37:50,767 +you'll see that it has. An argument bar button item, + +782 +00:37:50,769 --> 00:37:52,902 +it also has another argument wrecked. + +783 +00:37:52,904 --> 00:37:56,706 +Okay, and if you set the bar button item this just tells + +784 +00:37:56,708 --> 00:38:02,112 +the system where this pop over pops up from. So + +785 +00:38:02,114 --> 00:38:05,115 +here this redeploy bar button item is this little bar button + +786 +00:38:05,117 --> 00:38:07,651 +item in the upper right. And so we're just telling + +787 +00:38:07,653 --> 00:38:09,786 +the presentation controller that's gonna pop over, + +788 +00:38:09,788 --> 00:38:12,455 +pop this thing over, that this is the button that it + +789 +00:38:12,457 --> 00:38:15,759 +pops over from. And that's how it knows to put it up near it, + +790 +00:38:15,761 --> 00:38:17,460 +and to put that little triangle up there, + +791 +00:38:17,462 --> 00:38:20,196 +you see the triangle pointing to, to redeploy. We could of + +792 +00:38:20,198 --> 00:38:24,868 +said PPC question mark dot wrecked equals whatever. + +793 +00:38:24,870 --> 00:38:25,802 +And view equals whatever and + +794 +00:38:25,804 --> 00:38:28,204 +then it could pop over from any arbitrary rectangle, + +795 +00:38:28,206 --> 00:38:31,875 +anywhere in a view, okay. So you can do that as well. + +796 +00:38:31,877 --> 00:38:33,143 +So that's all we're doing here. + +797 +00:38:33,145 --> 00:38:36,880 +All we've added to this whole thing for pop over's just + +798 +00:38:36,882 --> 00:38:38,548 +made our presentation saw a pop over and + +799 +00:38:38,550 --> 00:38:42,252 +told the control, the pop over presentation controller, where + +800 +00:38:42,254 --> 00:38:45,322 +we want it to pop over from. That's all we've done. Okay, + +801 +00:38:45,324 --> 00:38:49,959 +now cool thing about this is this will work on iPhone 2. + +802 +00:38:49,961 --> 00:38:53,830 +So you can put this code in here. It will do this but + +803 +00:38:53,832 --> 00:38:55,799 +iPhone will continue to do this. And + +804 +00:38:55,801 --> 00:38:59,636 +why is that? That because of this adaptive presentation + +805 +00:38:59,638 --> 00:39:01,571 +style mechanism we talk about early in the core. + +806 +00:39:01,573 --> 00:39:04,341 +You might have forgot it by now. But it's the mechanism + +807 +00:39:04,343 --> 00:39:06,943 +that says if I try to put something up as a pop-over + +808 +00:39:06,945 --> 00:39:10,280 +on an iPhone, it says op, can't, we don't do pop-overs + +809 +00:39:10,282 --> 00:39:12,916 +on an iPhone so we're gonna present this thing modally. + +810 +00:39:12,918 --> 00:39:15,652 +So it presents it modally and this is what an action sheet + +811 +00:39:15,654 --> 00:39:18,288 +looks like, one presented modally, okay, versus + +812 +00:39:18,290 --> 00:39:22,792 +pop-over style So it's back to presenting the same way. Now, + +813 +00:39:22,794 --> 00:39:24,494 +of course, it doesn't even look at + +814 +00:39:24,496 --> 00:39:26,429 +this pop over presentation controller because + +815 +00:39:26,431 --> 00:39:29,432 +it didn't end up presenting it with the pop over style. + +816 +00:39:29,434 --> 00:39:31,901 +It adapted and presented it with a normal modal style. + +817 +00:39:31,903 --> 00:39:35,038 +So this is great. You can write this one code and + +818 +00:39:35,040 --> 00:39:37,841 +it'll work on both devices. Okay. + +819 +00:39:37,843 --> 00:39:42,412 +All right, what about alerts? Okay, + +820 +00:39:42,414 --> 00:39:45,181 +so alerts are almost exactly the same as Action Cheat. You + +821 +00:39:45,183 --> 00:39:49,152 +just say the style is Alert here instead of Action Cheat. + +822 +00:39:49,154 --> 00:39:53,590 +You still do all the same thing with Add Action, okay, + +823 +00:39:53,592 --> 00:39:56,659 +your Cancel Button and Add Action for + +824 +00:39:56,661 --> 00:39:57,861 +the login button. Okay? + +825 +00:39:57,863 --> 00:40:00,530 +So just like same thing we did with the cl, closures and + +826 +00:40:00,532 --> 00:40:03,166 +all that stuff right here. One thing that's different about + +827 +00:40:03,168 --> 00:40:05,802 +the alert, of course, you've got this text field. So how do + +828 +00:40:05,804 --> 00:40:08,371 +you deal with the fact there's text fields in an alert but + +829 +00:40:08,373 --> 00:40:11,174 +not an action sheet? And the answer is + +830 +00:40:11,176 --> 00:40:15,011 +AlertController has a method addTextFieldWithConfiguration- + +831 +00:40:15,013 --> 00:40:18,047 +Handler. This only does something on alerts, + +832 +00:40:18,049 --> 00:40:19,916 +it doesn't do anything if it's an action sheet. And + +833 +00:40:19,918 --> 00:40:23,787 +this closure will be called with the text field that + +834 +00:40:23,789 --> 00:40:27,457 +you're adding, and allow you to configure it in here. + +835 +00:40:27,459 --> 00:40:28,825 +So that's all this little closure does, + +836 +00:40:28,827 --> 00:40:31,027 +is just configuring the text field. So for example, + +837 +00:40:31,029 --> 00:40:34,097 +I want guidance system password as my placeholder + +838 +00:40:34,099 --> 00:40:36,766 +text in this text field, so I've just set textfield's + +839 +00:40:36,768 --> 00:40:40,804 +placeholder to be Guidance System Password there, okay. + +840 +00:40:40,806 --> 00:40:43,940 +So this adds a text field to the alert, and + +841 +00:40:43,942 --> 00:40:46,075 +this closure just lets you configure it. + +842 +00:40:46,077 --> 00:40:49,345 +Now, what happens when someone types in here? How do you get + +843 +00:40:49,347 --> 00:40:53,283 +the text out of there? Well in the action, like for + +844 +00:40:53,285 --> 00:40:56,352 +cancel, we went away, we, we don't even look at the text. + +845 +00:40:56,354 --> 00:40:58,955 +But for log in, I wanna look at this password. + +846 +00:40:58,957 --> 00:41:00,523 +So in the action closure here for + +847 +00:41:00,525 --> 00:41:03,092 +login, you see that right there, the action closure? + +848 +00:41:03,094 --> 00:41:09,232 +I'm going to say, if I can let tf = self.alert.textFields?, + +849 +00:41:09,234 --> 00:41:12,435 +is option because you don't always have text field .first. + +850 +00:41:12,437 --> 00:41:15,004 +Okay, I only have one text field so I want the first one. + +851 +00:41:15,006 --> 00:41:17,807 +Then, I've got the text field and I could, for example, + +852 +00:41:17,809 --> 00:41:21,044 +log in with the password tf.text. Okay, so + +853 +00:41:21,046 --> 00:41:24,380 +the answer is I use this text field's bar which is an array + +854 +00:41:24,382 --> 00:41:29,018 +of all the text fields that are in this alert. Okay, + +855 +00:41:29,020 --> 00:41:32,655 +so that's it, that's it for action alert. + +856 +00:41:32,657 --> 00:41:32,922 +Pretty easy to use, + +857 +00:41:32,924 --> 00:41:35,425 +you're almost certain to use them in your final project. + +858 +00:41:35,427 --> 00:41:38,394 +That's why I'm covering them early in the final project + +859 +00:41:38,396 --> 00:41:43,233 +period here. So hopefully that gives you all the things, + +860 +00:41:43,235 --> 00:41:48,104 +everything you need to know to do that. All right, and + +861 +00:41:48,106 --> 00:41:51,975 +of course, we present this thing exact same way, + +862 +00:41:51,977 --> 00:41:53,209 +presentViewController, okay. + +863 +00:41:53,211 --> 00:41:55,778 +It's just modally presented, happens to draw in this way, + +864 +00:41:55,780 --> 00:41:58,648 +but it's still just modally presented, so we use the same + +865 +00:41:58,650 --> 00:42:02,752 +presentViewController there, okay. And + +866 +00:42:02,754 --> 00:42:08,124 +it looks the same both on iPad and iPhone. All right, so + +867 +00:42:08,126 --> 00:42:10,593 +Cloud Kit. So I'm covering Cloud Kit, + +868 +00:42:10,595 --> 00:42:12,128 +again I don't usually cover Cloud Kit. But + +869 +00:42:12,130 --> 00:42:14,330 +I'm covering it this quarter because I think it's gonna be + +870 +00:42:14,332 --> 00:42:17,767 +something really cool and powerful for you to use for + +871 +00:42:17,769 --> 00:42:21,271 +your final projects, okay. So what is Cloud Kit? + +872 +00:42:21,273 --> 00:42:24,340 +Cloud Kit is a database in the cloud, okay. + +873 +00:42:24,342 --> 00:42:28,545 +It's a feature of iCloud and it's very simple to use, okay. + +874 +00:42:28,547 --> 00:42:31,614 +And it has very basic database operations, + +875 +00:42:31,616 --> 00:42:34,751 +okay. It's over the network, so everything that you're + +876 +00:42:34,753 --> 00:42:36,719 +doing is happening real time on the network, so + +877 +00:42:36,721 --> 00:42:40,189 +it's all asynchronous, of course. Because the network + +878 +00:42:40,191 --> 00:42:42,258 +could be slow or even not available, okay. + +879 +00:42:42,260 --> 00:42:44,794 +That requires you to do some thoughtful programing, + +880 +00:42:44,796 --> 00:42:47,363 +as you have learned with everything is asynchronous, + +881 +00:42:47,365 --> 00:42:49,766 +you kinda have to like, think about what it means for + +882 +00:42:49,768 --> 00:42:52,869 +these methods to, not call you back until much later, okay. + +883 +00:42:52,871 --> 00:42:56,272 +So, otherwise, it's really nice simple, database + +884 +00:42:56,274 --> 00:42:59,075 +mechanism to use. Here are the important concepts, + +885 +00:42:59,077 --> 00:43:02,745 +okay, that you need to know. One is record type. + +886 +00:43:02,747 --> 00:43:05,448 +Record type is like an entity in core data. + +887 +00:43:05,450 --> 00:43:07,517 +We're gonna do a lot of parallels to core data, + +888 +00:43:07,519 --> 00:43:11,387 +cuz you know core data so well so know that terminology, so + +889 +00:43:11,389 --> 00:43:14,023 +record type is kind of like entity. + +890 +00:43:14,025 --> 00:43:17,994 +Fields are like attributes. Okay, so fields + +891 +00:43:17,996 --> 00:43:21,497 +are the data that's stored in a record, type record. + +892 +00:43:21,499 --> 00:43:26,603 +A record is an instance of a record type. So I've got, + +893 +00:43:26,605 --> 00:43:31,207 +just like, it's like, sort of like NSManageObject in, + +894 +00:43:31,209 --> 00:43:34,377 +core data. But of course it's so much more lightweight, + +895 +00:43:34,379 --> 00:43:36,179 +there isn't any of that infrastructure. + +896 +00:43:36,181 --> 00:43:36,579 +But it's kind of like that, so + +897 +00:43:36,581 --> 00:43:40,283 +it's an instance of a certain record. A reference is kinda + +898 +00:43:40,285 --> 00:43:45,588 +like a relationship to another entity or another record type + +899 +00:43:45,590 --> 00:43:48,725 +there, okay reference. A database is a place where you + +900 +00:43:48,727 --> 00:43:53,529 +store your records. A zone is a sub-area of a database. + +901 +00:43:53,531 --> 00:43:54,864 +I'm not gonna talk about zones, but + +902 +00:43:54,866 --> 00:43:58,067 +if you divide your database up into zones you can do cool + +903 +00:43:58,069 --> 00:43:59,602 +things like, do efficient queries, + +904 +00:43:59,604 --> 00:44:02,171 +where you're only querying over a subset of your data, + +905 +00:44:02,173 --> 00:44:05,141 +like this in-sum zone. Okay, I'm not gonna talk about that, + +906 +00:44:05,143 --> 00:44:06,309 +but that's what a zone is all about, + +907 +00:44:06,311 --> 00:44:08,277 +it's a subarea of a database for searching and + +908 +00:44:08,279 --> 00:44:12,582 +stuff. A container is a collection of databases, we'll + +909 +00:44:12,584 --> 00:44:17,420 +talk about that. A query, is a NSPredicate based search. + +910 +00:44:17,422 --> 00:44:20,123 +Of course, NSPredicates can be quite a bit simpler, + +911 +00:44:20,125 --> 00:44:21,424 +because it's a simpler database, + +912 +00:44:21,426 --> 00:44:24,627 +but, it's still, similar to core data. You're gonna use, + +913 +00:44:24,629 --> 00:44:27,130 +actually use the class and its predicate to make '. + +914 +00:44:27,132 --> 00:44:31,734 +And then a subscription is a standing query, okay. + +915 +00:44:31,736 --> 00:44:34,837 +It's, basically an NSPredicate, you can upload to + +916 +00:44:34,839 --> 00:44:37,674 +the database, and any time it changes it will send you + +917 +00:44:37,676 --> 00:44:41,844 +a push notification, which is fantastic. This is the coolest + +918 +00:44:41,846 --> 00:44:45,014 +feature of all in Cloud Kit, is that it will send you push + +919 +00:44:45,016 --> 00:44:46,949 +notifications when the database changes, okay. + +920 +00:44:46,951 --> 00:44:49,786 +And then all you need to do is just, give it a standing + +921 +00:44:49,788 --> 00:44:52,855 +query, called a subscription, and it'll do that, okay. + +922 +00:44:52,857 --> 00:44:55,858 +All right, so let's talk about how all this works, + +923 +00:44:55,860 --> 00:44:59,562 +how do we make this Cloud Kit thing happen. First thing you + +924 +00:44:59,564 --> 00:45:02,298 +have to understand about Cloud Kit is a very important thing + +925 +00:45:02,300 --> 00:45:05,902 +here called the Cloud Kit Dashboard. This is a website, + +926 +00:45:05,904 --> 00:45:09,672 +okay. You get to it by going to your project, okay, + +927 +00:45:09,674 --> 00:45:11,541 +click on your project. Actually, + +928 +00:45:11,543 --> 00:45:13,476 +I'll show in a second how you can get to this. But + +929 +00:45:13,478 --> 00:45:14,844 +you can click somewhere in your project, and + +930 +00:45:14,846 --> 00:45:16,379 +it's gonna take you to this website. + +931 +00:45:16,381 --> 00:45:18,848 +This is gonna have all your record types, + +932 +00:45:18,850 --> 00:45:19,882 +all your entities, and + +933 +00:45:19,884 --> 00:45:22,118 +all of their fields, all their attributes. + +934 +00:45:22,120 --> 00:45:25,722 +So here's an entity called QandA, it's a question and + +935 +00:45:25,724 --> 00:45:27,824 +answer thing. Here's, it's got answers, + +936 +00:45:27,826 --> 00:45:30,526 +which is a list of strings, an array of strings, + +937 +00:45:30,528 --> 00:45:33,463 +and it's got a question, which is a single string. And + +938 +00:45:33,465 --> 00:45:36,766 +these are all indexed, both for querying and searching and + +939 +00:45:36,768 --> 00:45:39,769 +even sorting, okay. Here's another one, + +940 +00:45:39,771 --> 00:45:42,538 +response, it's got some things. Over here, okay, + +941 +00:45:42,540 --> 00:45:46,209 +you can actually go to default zone right here, you'll + +942 +00:45:46,211 --> 00:45:50,213 +be able to actually see the data stored in these records, + +943 +00:45:50,215 --> 00:45:53,883 +which is kinda cool. And then it's got some other + +944 +00:45:53,885 --> 00:45:57,153 +things here like the subscriptions that you have + +945 +00:45:57,155 --> 00:45:58,921 +outstanding out there. + +946 +00:45:58,923 --> 00:46:01,324 +Maybe any users that are using the database etc. + +947 +00:46:01,326 --> 00:46:03,960 +So this is kind of your place where you're gonna go to find + +948 +00:46:03,962 --> 00:46:06,729 +out everything that's going on in your database in real time, + +949 +00:46:06,731 --> 00:46:11,934 +'kay. The dashboard also has interesting + +950 +00:46:11,936 --> 00:46:14,837 +metadata indexes, and I'm putting a slide on this, + +951 +00:46:14,839 --> 00:46:18,274 +cuz this is easy to forget. Okay, because, of course, + +952 +00:46:18,276 --> 00:46:21,210 +the QandA thing has answers and question fields, but + +953 +00:46:21,212 --> 00:46:24,380 +it also has these fields like the record ID which is + +954 +00:46:24,382 --> 00:46:28,785 +a unique ID for this QandA record. Also, created by, + +955 +00:46:28,787 --> 00:46:32,421 +that's the user who created it, that's very interesting. + +956 +00:46:32,423 --> 00:46:33,689 +The date it was created. + +957 +00:46:33,691 --> 00:46:36,392 +So these are all kind of fields you always get, and + +958 +00:46:36,394 --> 00:46:39,529 +by default none of them are index however. So if you + +959 +00:46:39,531 --> 00:46:42,732 +wanted to search and say show me all the QandA's that were + +960 +00:46:42,734 --> 00:46:45,668 +created by a certain user, that wouldn't work, unless you + +961 +00:46:45,670 --> 00:46:50,439 +go in here in the dashboard and turn on query index for + +962 +00:46:50,441 --> 00:46:53,142 +created by. Okay, so don't forget about this. This is + +963 +00:46:53,144 --> 00:46:56,045 +something easy to forget to do cuz they're automatic off and + +964 +00:46:56,047 --> 00:46:59,882 +you're like how come that they won't show me all the QandA's + +965 +00:46:59,884 --> 00:47:00,683 +by this user, + +966 +00:47:00,685 --> 00:47:04,187 +it's because it's not indexed, okay. So that, + +967 +00:47:04,189 --> 00:47:05,721 +you need to click on this little guy here, + +968 +00:47:05,723 --> 00:47:09,425 +metadata indexes, to show this. Okay now, + +969 +00:47:09,427 --> 00:47:14,130 +that schema that we're talking about there, the entities and + +970 +00:47:14,132 --> 00:47:16,566 +the attributes okay, the record types and the fields, + +971 +00:47:16,568 --> 00:47:20,536 +you can create it all in the dashboard if you want, but + +972 +00:47:20,538 --> 00:47:21,204 +you don't have to. + +973 +00:47:21,206 --> 00:47:23,940 +You can just start creating them in your code and + +974 +00:47:23,942 --> 00:47:26,209 +it'll automatically create the schema for you. Every time + +975 +00:47:26,211 --> 00:47:28,644 +you will reference an entity that wasn't there before, + +976 +00:47:28,646 --> 00:47:31,347 +it's gonna create a new entity for it. Every time you access + +977 +00:47:31,349 --> 00:47:35,051 +a field on a certain entity, you know, record type, + +978 +00:47:35,053 --> 00:47:37,720 +it's gonna create an attribute automatically. Now, + +979 +00:47:37,722 --> 00:47:40,122 +you're still gonna have to go to dashboard and turn on or + +980 +00:47:40,124 --> 00:47:43,159 +off any indexes and things like that, but + +981 +00:47:43,161 --> 00:47:45,761 +it's just gonna create it all for you on the fly. + +982 +00:47:45,763 --> 00:47:48,231 +That only happens though during development, + +983 +00:47:48,233 --> 00:47:50,867 +once you deploy your app over at the app store, + +984 +00:47:50,869 --> 00:47:52,535 +now that's not true anymore, okay. + +985 +00:47:52,537 --> 00:47:56,572 +So your app has to have its schema built in development + +986 +00:47:56,574 --> 00:48:00,476 +and then you export that schema. When you run in + +987 +00:48:00,478 --> 00:48:05,214 +deployment environment, okay? So this is really cool for + +988 +00:48:05,216 --> 00:48:07,884 +development because you don't have to do a lot of tedious + +989 +00:48:07,886 --> 00:48:12,154 +creating of things in your in your dashboard. + +990 +00:48:12,156 --> 00:48:14,657 +And you can always go in the dashboard and delete things. + +991 +00:48:14,659 --> 00:48:18,060 +And it's really actually quite flexible and cool. + +992 +00:48:18,062 --> 00:48:22,031 +Now none of this will work until you unable Cloud Kit + +993 +00:48:22,033 --> 00:48:24,800 +in your capabilities. Remember I'd show you the capabilities + +994 +00:48:24,802 --> 00:48:28,337 +earlier. You go to the very top one here iCloud and + +995 +00:48:28,339 --> 00:48:30,072 +you're gonna click this from off to on. + +996 +00:48:30,074 --> 00:48:32,975 +Okay if you don't do that none of this works. So + +997 +00:48:32,977 --> 00:48:36,746 +when you click it to on. You get this settings right here. + +998 +00:48:36,748 --> 00:48:40,316 +You're gonna wanna click this switch right here Cloud Kit. + +999 +00:48:40,318 --> 00:48:41,884 +That's all this stuff I'm gonna be talking about here in + +1000 +00:48:41,886 --> 00:48:45,454 +this lecture, okay? Cloud Kit. There's also Key Value Storage + +1001 +00:48:45,456 --> 00:48:49,125 +which is kind of cool, you can store like an NS user defaults + +1002 +00:48:49,127 --> 00:48:50,893 +on the Cloud. That's kind of cool features. + +1003 +00:48:50,895 --> 00:48:53,262 +Well, I'm not gonna talk about that. It's there if you wanna + +1004 +00:48:53,264 --> 00:48:56,766 +do it and of course you can store documents in the Cloud. + +1005 +00:48:56,768 --> 00:48:59,268 +Manage document Remember that from core data? + +1006 +00:48:59,270 --> 00:49:02,905 +It stores all the core data stuff in the cloud, okay? + +1007 +00:49:02,907 --> 00:49:04,440 +So, so you could have that as well. + +1008 +00:49:04,442 --> 00:49:08,644 +But today, we're talking about this Cloud Kit right here, + +1009 +00:49:08,646 --> 00:49:11,047 +all right? This button right here, + +1010 +00:49:11,049 --> 00:49:12,715 +is how you get to that Cloud Kit dashboard. + +1011 +00:49:12,717 --> 00:49:16,786 +This will open up your browser and take you to that thing, + +1012 +00:49:16,788 --> 00:49:22,725 +for you. Kay? This right here is the containers. Remember I + +1013 +00:49:22,727 --> 00:49:25,895 +said a container is a thing that contains databases. + +1014 +00:49:25,897 --> 00:49:29,198 +We're only gonna talk about use default container here. + +1015 +00:49:29,200 --> 00:49:32,201 +But you're gonna actually create your custom containers. + +1016 +00:49:32,203 --> 00:49:35,771 +And what's cool about these containers is these containers + +1017 +00:49:35,773 --> 00:49:39,809 +can be used across different kinds of apps. Okay? + +1018 +00:49:39,811 --> 00:49:41,544 +In other words, you might be a company in + +1019 +00:49:41,546 --> 00:49:43,779 +your shipment four different apps, and + +1020 +00:49:43,781 --> 00:49:45,314 +they wanted to share data. + +1021 +00:49:45,316 --> 00:49:49,085 +They can do that by creating a shared container, okay? + +1022 +00:49:49,087 --> 00:49:52,521 +The default container is just to use by your one app, okay? + +1023 +00:49:52,523 --> 00:49:56,225 +I'm shipping to my app, all my users of that one app can use + +1024 +00:49:56,227 --> 00:49:59,295 +this default container. Okay, and that's what I'm gonna + +1025 +00:49:59,297 --> 00:50:01,764 +talk about today, but you can just know that this custom + +1026 +00:50:01,766 --> 00:50:04,900 +container feature is available for your final project, + +1027 +00:50:04,902 --> 00:50:07,103 +the default container's gonna be plenty, okay? + +1028 +00:50:07,105 --> 00:50:10,339 +All right, so let's talk about these containers and + +1029 +00:50:10,341 --> 00:50:13,542 +what's in them, okay? And because we need to know that, + +1030 +00:50:13,544 --> 00:50:15,411 +so we can create records in the database, + +1031 +00:50:15,413 --> 00:50:19,115 +okay? So we get a database from the container. + +1032 +00:50:19,117 --> 00:50:21,884 +Remember, I said container contains databases. + +1033 +00:50:21,886 --> 00:50:25,855 +And the default container actually has two databases, + +1034 +00:50:25,857 --> 00:50:28,858 +a public database and a private database. + +1035 +00:50:28,860 --> 00:50:31,260 +The difference between these two is that the private + +1036 +00:50:31,262 --> 00:50:35,564 +database can only be looked at by the currently logged in + +1037 +00:50:35,566 --> 00:50:39,902 +iCloud user. Okay, so you know how on your phone, hopefully, + +1038 +00:50:39,904 --> 00:50:42,338 +you're logged into iCloud, right? Okay, so, + +1039 +00:50:42,340 --> 00:50:46,409 +whatever that login is, only the person logged in as that + +1040 +00:50:46,411 --> 00:50:49,612 +iCloud can see the private database for that iCloud view. + +1041 +00:50:49,614 --> 00:50:50,346 +So, it is exactly what it sounds like, + +1042 +00:50:50,348 --> 00:50:53,449 +it is private information. The public database can be seen by + +1043 +00:50:53,451 --> 00:50:58,988 +anybody, okay, anybody who is running your app. Can see + +1044 +00:50:58,990 --> 00:51:02,324 +this public database. Got the difference between public and + +1045 +00:51:02,326 --> 00:51:05,094 +private? So public is where you're gonna have data that's + +1046 +00:51:05,096 --> 00:51:08,130 +shared between your users, private data is where you're + +1047 +00:51:08,132 --> 00:51:11,200 +gonna have data that the user sees on all their devices but + +1048 +00:51:11,202 --> 00:51:15,404 +the other users can't see. All right. So that's how you + +1049 +00:51:15,406 --> 00:51:17,406 +get the database. Once you have the database. + +1050 +00:51:17,408 --> 00:51:18,441 +You can do all kinds of things. + +1051 +00:51:18,443 --> 00:51:20,609 +Create records query all kinds of stuff. + +1052 +00:51:20,611 --> 00:51:24,180 +So let's starts with how to create record on the database. + +1053 +00:51:24,182 --> 00:51:27,583 +Okay. You create a record first of all by distributing + +1054 +00:51:27,585 --> 00:51:31,320 +CKRecord, Cloud Kit record and all you do is specified + +1055 +00:51:31,322 --> 00:51:34,190 +the record type. Okay, that's like the entity name, + +1056 +00:51:34,192 --> 00:51:37,560 +like tweet or Twitter user, whatever, it's just a string, + +1057 +00:51:37,562 --> 00:51:40,396 +okay. If that entity doesn't exist in the database when you + +1058 +00:51:40,398 --> 00:51:45,301 +save this record, it'll create that entity, okay? Make sense? + +1059 +00:51:45,303 --> 00:51:48,170 +All right, so now you have this record, okay? + +1060 +00:51:48,172 --> 00:51:51,474 +How do you put information into the record? Well, you use + +1061 +00:51:51,476 --> 00:51:55,177 +a dictionary-like syntax. So here I've got a record, + +1062 +00:51:55,179 --> 00:52:00,015 +right here. And I'm adding some fields to it by saying, + +1063 +00:52:00,017 --> 00:52:03,219 +records of text equals something, records of created + +1064 +00:52:03,221 --> 00:52:05,754 +equals something, records of items equals something, So, + +1065 +00:52:05,756 --> 00:52:07,490 +you see how ithat looks a dictionary? It looks like + +1066 +00:52:07,492 --> 00:52:10,526 +records is almost a dictionary right there And so + +1067 +00:52:10,528 --> 00:52:13,462 +that's actually use it, now what are these values, + +1068 +00:52:13,464 --> 00:52:15,564 +these things that I have dot, dot, dot right here, + +1069 +00:52:15,566 --> 00:52:18,267 +what are these? Well, these can only be things + +1070 +00:52:18,269 --> 00:52:22,338 +that implement the protocol CKRecordValue, okay? And + +1071 +00:52:22,340 --> 00:52:24,874 +the only things the implement that protocol are these seven + +1072 +00:52:24,876 --> 00:52:29,178 +things in green. Strings, numbers, arrays and dates. + +1073 +00:52:29,180 --> 00:52:32,148 +And of course, we get the bridged Swift types, so + +1074 +00:52:32,150 --> 00:52:36,352 +that means doubles, ints, string, array, okay? And + +1075 +00:52:36,354 --> 00:52:39,989 +then also these three special things, CKReference, + +1076 +00:52:39,991 --> 00:52:42,758 +CKAssett and CLLocation, okay? + +1077 +00:52:42,760 --> 00:52:47,930 +Now array can be array of any of the other types. Okay? + +1078 +00:52:47,932 --> 00:52:49,865 +The array of any of these other green things. + +1079 +00:52:49,867 --> 00:52:52,268 +So you can have an array of numbers, array of strings, + +1080 +00:52:52,270 --> 00:52:56,305 +array of dates, + +1081 +00:52:56,307 --> 00:53:00,643 +CKReference is a reference to another record. Okay, so this + +1082 +00:53:00,645 --> 00:53:03,712 +is how you do relationships, okay? So you have a record. + +1083 +00:53:03,714 --> 00:53:09,318 +So again, if you had tweeter, and the tweets, okay? + +1084 +00:53:09,320 --> 00:53:12,955 +The tweet record type would have a field + +1085 +00:53:12,957 --> 00:53:18,861 +that is a CKReference to a Twitter user, okay? + +1086 +00:53:18,863 --> 00:53:23,599 +CKAsset is for storing big things, like images, sounds, + +1087 +00:53:23,601 --> 00:53:28,370 +video, okay, files basically. Now, This cloud kit does + +1088 +00:53:28,372 --> 00:53:31,507 +a really cool job of when you put something in the cloud it + +1089 +00:53:31,509 --> 00:53:34,376 +doesn't immediately just start cranking on the network piling + +1090 +00:53:34,378 --> 00:53:37,813 +that thing up on the net, it stores it locally and + +1091 +00:53:37,815 --> 00:53:40,182 +when it wants to, when there's good network connection, + +1092 +00:53:40,184 --> 00:53:44,386 +whatever, it's uploading it to the cloud. And vice versa. So + +1093 +00:53:44,388 --> 00:53:46,021 +It's doing all this behind the scenes and + +1094 +00:53:46,023 --> 00:53:46,388 +being very efficient and + +1095 +00:53:46,390 --> 00:53:50,092 +caching it etc. CL location, we're gonna talk about next + +1096 +00:53:50,094 --> 00:53:52,394 +week when we talk about maps and locations. + +1097 +00:53:52,396 --> 00:53:55,831 +It's just a GPS coordinate, okay, someplace on earth, + +1098 +00:53:55,833 --> 00:54:00,102 +so you can store something as a GPS coordinate. Okay, so + +1099 +00:54:00,104 --> 00:54:02,938 +that's it, it's super. Easy to create these records. Again as + +1100 +00:54:02,940 --> 00:54:05,608 +you put these field names in here if that doesn't exist in + +1101 +00:54:05,610 --> 00:54:08,677 +the schema it's just gonna add that field okay as soon as you + +1102 +00:54:08,679 --> 00:54:11,614 +store this to the database. So here we've created the record + +1103 +00:54:11,616 --> 00:54:13,749 +but we haven't stored it yet okay it's not it hasn't been + +1104 +00:54:13,751 --> 00:54:16,585 +uploaded to the network we've only created it locally. + +1105 +00:54:16,587 --> 00:54:21,590 +So how do we get the information. So we + +1106 +00:54:21,592 --> 00:54:24,927 +saw how to put the information record how do we get it out + +1107 +00:54:24,929 --> 00:54:26,395 +You again use dictionary syntax, + +1108 +00:54:26,397 --> 00:54:29,965 +so recor|"text| to get the text out of the record. But + +1109 +00:54:29,967 --> 00:54:34,737 +you have to cast, because all of these things come back as + +1110 +00:54:34,739 --> 00:54:38,274 +CKRecordValues. Okay? Cuz I told you, the only things that + +1111 +00:54:38,276 --> 00:54:40,943 +can go in are things that implement that protocol. + +1112 +00:54:40,945 --> 00:54:42,511 +So when you get it out, it comes out, + +1113 +00:54:42,513 --> 00:54:44,346 +it's a thing that implements that protocol. + +1114 +00:54:44,348 --> 00:54:45,180 +So you have to cast it. + +1115 +00:54:45,182 --> 00:54:49,251 +To the thing it actually is, okay. Make sense? That's why + +1116 +00:54:49,253 --> 00:54:52,254 +even like records of items. That's an array of strings. + +1117 +00:54:52,256 --> 00:54:56,292 +You have to say as array of string, okay, got it. + +1118 +00:54:56,294 --> 00:54:58,827 +And of course, these all will be optional because as + +1119 +00:54:58,829 --> 00:55:03,432 +question mark. So I might wanna say if let on all these. + +1120 +00:55:03,434 --> 00:55:08,070 +Okay. Now, I've got the record creator, how do I put it into + +1121 +00:55:08,072 --> 00:55:11,707 +the database? It's, actually, the real answer is, or + +1122 +00:55:11,709 --> 00:55:15,010 +the full answer is you're gonna create an NSOperation, + +1123 +00:55:15,012 --> 00:55:17,680 +okay? Do you remember NSOperation, NSOperationQueue? + +1124 +00:55:17,682 --> 00:55:21,450 +That's the object-oriented version of the GCD, right? + +1125 +00:55:21,452 --> 00:55:22,251 +Dispatch async and + +1126 +00:55:22,253 --> 00:55:26,155 +all that stuff So the way you actually create + +1127 +00:55:26,157 --> 00:55:28,757 +records in the database is you create a special kind of + +1128 +00:55:28,759 --> 00:55:33,529 +NS operation called CKModifyRecordsOperation and + +1129 +00:55:33,531 --> 00:55:36,365 +you can give it a bunch of records and you create and + +1130 +00:55:36,367 --> 00:55:40,369 +NS or operation cue, okay. You could use the main cue, okay, + +1131 +00:55:40,371 --> 00:55:43,405 +or you can create you're own cue. Those cues are just like + +1132 +00:55:43,407 --> 00:55:45,774 +threads, okay, they're like Not like threads, + +1133 +00:55:45,776 --> 00:55:48,010 +they're cues, just like dispatch under bar cue, + +1134 +00:55:48,012 --> 00:55:51,847 +under bar tee things. And then you just tell that, if you put + +1135 +00:55:51,849 --> 00:55:55,617 +this ModifyRecordsOperation on a cue it'll go and + +1136 +00:55:55,619 --> 00:55:56,318 +execute it and + +1137 +00:55:56,320 --> 00:55:57,219 +update the database. But + +1138 +00:55:57,221 --> 00:56:00,422 +that's a little bit of a pain in the neck to go do all that, + +1139 +00:56:00,424 --> 00:56:04,159 +okay. So there's a nice little convenience method right in + +1140 +00:56:04,161 --> 00:56:08,397 +database called save record. And it just takes a record and + +1141 +00:56:08,399 --> 00:56:10,666 +a completion handler. And it saves the record and + +1142 +00:56:10,668 --> 00:56:12,935 +calls your completion handler when it's done. Okay, and + +1143 +00:56:12,937 --> 00:56:15,571 +remember that can be quite a ways later because this is + +1144 +00:56:15,573 --> 00:56:17,506 +happening over the network. Your network might be slow, + +1145 +00:56:17,508 --> 00:56:19,942 +you might be out of range of network, whatever. So + +1146 +00:56:19,944 --> 00:56:22,745 +it can take a very, very long time for this to come back. + +1147 +00:56:22,747 --> 00:56:27,116 +It could even possibly time out but this is how it works. + +1148 +00:56:27,118 --> 00:56:28,283 +S this is on the database. + +1149 +00:56:28,285 --> 00:56:29,051 +Remember the public database or + +1150 +00:56:29,053 --> 00:56:32,087 +the private database that you got from the container? + +1151 +00:56:32,089 --> 00:56:34,556 +That's where you send this method. Okay? + +1152 +00:56:34,558 --> 00:56:37,292 +Now this thing cant do everything that this whole + +1153 +00:56:37,294 --> 00:56:42,765 +NSoperationQ can write multiple records at once. + +1154 +00:56:42,767 --> 00:56:45,200 +It also knows how to overwrite a newer version. + +1155 +00:56:45,202 --> 00:56:47,703 +Okay, this does optimistic locking right here, the save + +1156 +00:56:47,705 --> 00:56:50,906 +record one. So if it tries to write something and there's + +1157 +00:56:50,908 --> 00:56:54,076 +a newer version of that thing it's just gonna fail. + +1158 +00:56:54,078 --> 00:56:54,510 +Report an error. + +1159 +00:56:54,512 --> 00:56:58,747 +It'll come back with an error here in the handler whereas + +1160 +00:56:58,749 --> 00:57:01,683 +the modify records operation knows how to + +1161 +00:57:01,685 --> 00:57:05,421 +overwrite what's in there. But save record for + +1162 +00:57:05,423 --> 00:57:07,923 +the most part does what you want most of the time. And for + +1163 +00:57:07,925 --> 00:57:10,559 +your final project this is gonna be plenty probably. + +1164 +00:57:10,561 --> 00:57:13,996 +Okay, but you're not gonna need this operation thing. + +1165 +00:57:14,365 --> 00:57:16,999 +All right, this happens all asychronously. + +1166 +00:57:17,001 --> 00:57:19,768 +Be very careful specially be careful with the fact + +1167 +00:57:19,770 --> 00:57:23,439 +that your closure they gets cold when they save record is + +1168 +00:57:23,441 --> 00:57:27,109 +finished Happens on another thread besides the main queue. + +1169 +00:57:27,111 --> 00:57:28,510 +Okay, it's not in the main queue. + +1170 +00:57:28,512 --> 00:57:31,413 +So you need to dispatch async back to the main queue from + +1171 +00:57:31,415 --> 00:57:33,849 +there if you want to do some UI stuff when + +1172 +00:57:33,851 --> 00:57:37,486 +that record is saved. It make sense? Okay, and + +1173 +00:57:37,488 --> 00:57:39,388 +you also just need an architecture code properly. + +1174 +00:57:39,390 --> 00:57:42,524 +You need to think about the whole design of your app + +1175 +00:57:42,526 --> 00:57:45,093 +when the data that's appearing in it + +1176 +00:57:45,095 --> 00:57:46,962 +might be coming asychronously. So + +1177 +00:57:46,964 --> 00:57:50,098 +you need to know how to have apps that have basically blank + +1178 +00:57:50,100 --> 00:57:52,935 +UIs with either spinning wheels or Loading or + +1179 +00:57:52,937 --> 00:57:55,471 +something on there, so the user knows what's going on. + +1180 +00:57:55,473 --> 00:57:57,673 +And, when the data comes, it populates it. Okay? + +1181 +00:57:57,675 --> 00:58:00,008 +It's very similar to, you do the smash tag where + +1182 +00:58:00,010 --> 00:58:02,544 +you have the little profile images, and they come up and + +1183 +00:58:02,546 --> 00:58:06,148 +they were blank. And then they just started filling in. Same + +1184 +00:58:06,150 --> 00:58:08,517 +kind of thing here, you have data in your database that + +1185 +00:58:08,519 --> 00:58:11,119 +starts out, you don't have it and then it starts filling in. + +1186 +00:58:11,121 --> 00:58:14,389 +And what does that mean for the user? Means things should + +1187 +00:58:14,391 --> 00:58:17,259 +start appearing over time. So you gotta think about how to + +1188 +00:58:17,261 --> 00:58:21,730 +architect your app to use asyncronity. All right, so + +1189 +00:58:21,732 --> 00:58:22,664 +here's what it looks like to create + +1190 +00:58:22,666 --> 00:58:24,867 +a record in the database all put together here. + +1191 +00:58:24,869 --> 00:58:26,435 +So I'm going to create a tweet right here. + +1192 +00:58:26,437 --> 00:58:29,404 +So here I'm letting tweet equal ckrecord. + +1193 +00:58:29,406 --> 00:58:29,972 +Just created a record. + +1194 +00:58:29,974 --> 00:58:32,908 +I'm gonna have the Tweets text to be 140 characters of pure + +1195 +00:58:32,910 --> 00:58:35,811 +joy. Then I'm gonna get my database by saying + +1196 +00:58:35,813 --> 00:58:38,380 +CKContainer.defaultContainer publicCloudDatabase. So I'm + +1197 +00:58:38,382 --> 00:58:40,949 +gonna put this in the public database that all users of my + +1198 +00:58:40,951 --> 00:58:44,219 +app can see. Then I'm just gonna ask the database to save + +1199 +00:58:44,221 --> 00:58:47,322 +the record Tweet, right. Here's that record Tweet and + +1200 +00:58:47,324 --> 00:58:49,591 +it's gonna call this closure, this big thing, + +1201 +00:58:49,593 --> 00:58:53,195 +when it's done. And this closure test two arguments, + +1202 +00:58:53,197 --> 00:58:55,264 +the record that it saved or + +1203 +00:58:55,266 --> 00:59:00,068 +nil if it failed to save it and an error, okay. + +1204 +00:59:00,070 --> 00:59:05,073 +Again, nil if it saved it, not nil if it failed to save it, + +1205 +00:59:05,075 --> 00:59:07,476 +okay. It doesn't return anything and so here's why + +1206 +00:59:07,478 --> 00:59:10,345 +doing my closure almost all of the time first I'm gonna say, + +1207 +00:59:10,347 --> 00:59:12,748 +if the error equals nil Hooray okay, + +1208 +00:59:12,750 --> 00:59:15,684 +it saved it successfully, so now I do whatever I do when + +1209 +00:59:15,686 --> 00:59:19,421 +it was successfully saved. Maybe nothing okay? Maybe I do + +1210 +00:59:19,423 --> 00:59:23,592 +something else, I don't know, but here's success. Sometimes + +1211 +00:59:23,594 --> 00:59:27,362 +there are 29 different errors in ck error code, so + +1212 +00:59:27,364 --> 00:59:31,300 +a lot of things can go wrong. Network unavailable, all kinds + +1213 +00:59:31,302 --> 00:59:35,003 +of things I just showed you how you handle these by + +1214 +00:59:35,005 --> 00:59:37,439 +picking one at random, which is not authenticated. + +1215 +00:59:37,441 --> 00:59:40,008 +Okay? Let's say the person is not logged into iCloud. + +1216 +00:59:40,010 --> 00:59:42,578 +Kay? They just never went to their settings and + +1217 +00:59:42,580 --> 00:59:43,545 +logged into iCloud. Okay? So + +1218 +00:59:43,547 --> 00:59:46,515 +you're gonna get this error, CKErrorCode.NotAuthenticated. + +1219 +00:59:46,517 --> 00:59:49,017 +Don't forget put, to put .rawValue so you get it as + +1220 +00:59:49,019 --> 00:59:51,753 +an integer because this error code is an integer. And + +1221 +00:59:51,755 --> 00:59:54,456 +so if there's that then I'm gonna maybe put up an alert + +1222 +00:59:54,458 --> 00:59:58,360 +code that "Please log in to iCloud" or something, right? + +1223 +00:59:58,362 --> 01:00:02,664 +And there's 29 other errors and so doing this programming + +1224 +01:00:02,666 --> 01:00:07,336 +really right, is a lot of error handling code. Okay, so + +1225 +01:00:07,338 --> 01:00:10,472 +in your final project You know the more you do of + +1226 +01:00:10,474 --> 01:00:13,275 +this the more it's kind of like you can get forming + +1227 +01:00:13,277 --> 01:00:15,877 +a one-point use of Cloud kit to a two-point use if you + +1228 +01:00:15,879 --> 01:00:18,413 +actually handle the error, you see what I'm saying? + +1229 +01:00:18,415 --> 01:00:20,983 +I don't expect you to handle every single error and + +1230 +01:00:20,985 --> 01:00:23,485 +uh-uh you get zero points, okay. Of course not, okay, + +1231 +01:00:23,487 --> 01:00:26,521 +the more error you handle, the more robust you are, + +1232 +01:00:26,523 --> 01:00:27,723 +the better you're a synchronize use, + +1233 +01:00:27,725 --> 01:00:30,859 +the more depth point you might get working in Cloud, + +1234 +01:00:30,861 --> 01:00:34,062 +Cloud kit Okay, but there's lots of other errors here. + +1235 +01:00:34,064 --> 01:00:35,597 +I'll show you some other errors that were going to + +1236 +01:00:35,599 --> 01:00:38,033 +handle in some other, ones in a second here. + +1237 +01:00:38,035 --> 01:00:39,868 +But this is how you're going to do it. Else if, else if, + +1238 +01:00:39,870 --> 01:00:43,572 +else if, or you could just switch on the error code, + +1239 +01:00:43,574 --> 01:00:46,375 +to go to handling errors. Okay. + +1240 +01:00:46,377 --> 01:00:49,945 +I mean, at worst, you could just either put an alert up, + +1241 +01:00:49,947 --> 01:00:52,748 +because the user is saying unknown error or something, or + +1242 +01:00:52,750 --> 01:00:55,150 +you could print something on the console. I don't know. + +1243 +01:00:55,152 --> 01:00:58,120 +But it's usually you want to try and collect + +1244 +01:00:58,122 --> 01:01:01,990 +all the errors that you can do something about, okay? + +1245 +01:01:01,992 --> 01:01:06,361 +Now again if tweet the entity doesn't exist in the database + +1246 +01:01:06,363 --> 01:01:10,265 +it's gonna create it, okay? If text field doesn't exist on + +1247 +01:01:10,267 --> 01:01:12,834 +this it's gonna create that attribute automatically for + +1248 +01:01:12,836 --> 01:01:16,405 +me. Okay, so that's it. That's how you put a record in + +1249 +01:01:16,407 --> 01:01:20,909 +the database real easy. Okay? Now, there's + +1250 +01:01:20,911 --> 01:01:24,613 +a special kind of error, that you can get sometimes, + +1251 +01:01:24,615 --> 01:01:30,318 +where, it will actually give you a retry time interval. So, + +1252 +01:01:30,320 --> 01:01:34,790 +not all errors have this, but some errors when you get them, + +1253 +01:01:34,792 --> 01:01:35,724 +Cloud Kit is basically saying hey, + +1254 +01:01:35,726 --> 01:01:38,627 +you know this is the kinda area you probably wanna retry, + +1255 +01:01:38,629 --> 01:01:41,329 +and here's a good amount of time to try, okay. + +1256 +01:01:41,331 --> 01:01:44,866 +So it's basically telling you what an appropriate retry + +1257 +01:01:44,868 --> 01:01:45,300 +interval would be. + +1258 +01:01:45,302 --> 01:01:49,171 +And I believe if things continue to fail it, you know, + +1259 +01:01:49,173 --> 01:01:51,473 +adds, makes the retry interval a little bit longer, + +1260 +01:01:51,475 --> 01:01:54,242 +until it just gives up and says don't retry anymore. + +1261 +01:01:54,244 --> 01:01:55,944 +More, but here is how you get it. + +1262 +01:01:55,946 --> 01:01:59,114 +Error the NSError that you get back here in addition I have + +1263 +01:01:59,116 --> 01:02:02,284 +an error it also has a user info dictionary and + +1264 +01:02:02,286 --> 01:02:07,055 +in that dictionary is a key CKError retry after key and + +1265 +01:02:07,057 --> 01:02:10,559 +it's an NS time interval okay it's actually an NS number but + +1266 +01:02:10,561 --> 01:02:13,328 +you're gonna cast it to an NS time interval there And + +1267 +01:02:13,330 --> 01:02:16,298 +then you gonna wanna dispatch back to the main queue because + +1268 +01:02:16,300 --> 01:02:17,365 +you gonna wanna have do a timer and + +1269 +01:02:17,367 --> 01:02:20,102 +we know that we do our timers on the main queue. And so I'm + +1270 +01:02:20,104 --> 01:02:23,505 +gonna schedule a timer with that retry interval I'm just + +1271 +01:02:23,507 --> 01:02:27,609 +gonna call some method but will probably try this again. + +1272 +01:02:27,611 --> 01:02:30,846 +Okay maybe calls a method that this is in in fact. + +1273 +01:02:31,081 --> 01:02:35,817 +Okay I found So basically something might put in + +1274 +01:02:35,819 --> 01:02:38,453 +any kind of error that you'd be willing to retry. + +1275 +01:02:38,455 --> 01:02:41,590 +Just check to see if there's a retry interval, there's is. + +1276 +01:02:41,592 --> 01:02:43,992 +Give it a go. Try it again. Okay, + +1277 +01:02:43,994 --> 01:02:46,762 +and if there is no retry interval then of course, + +1278 +01:02:46,764 --> 01:02:51,266 +this won't happen. You won't be doing this timer thing. + +1279 +01:02:51,268 --> 01:02:55,403 +Got it? Okay, now we've got the records stored. + +1280 +01:02:55,405 --> 01:02:58,406 +Now we want to get them, okay? So we basically want a query + +1281 +01:02:58,408 --> 01:03:02,577 +to get them. And querying is also super, super simple here. + +1282 +01:03:02,579 --> 01:03:05,347 +You're just gonna do performQuery on the database. + +1283 +01:03:05,349 --> 01:03:07,549 +Just like you did saveRecord on the database you're gonna + +1284 +01:03:07,551 --> 01:03:09,184 +do performQuery and give it a query. + +1285 +01:03:09,186 --> 01:03:11,920 +I'll talk about in a second. This inZoneWithID, + +1286 +01:03:11,922 --> 01:03:15,724 +remember I've told you there were zones, subdatabase zones, + +1287 +01:03:15,726 --> 01:03:19,161 +okay. So you can specify a zone there, or nil, actually + +1288 +01:03:19,163 --> 01:03:24,232 +that's an optional string, so that could be nil. But if you + +1289 +01:03:24,234 --> 01:03:27,068 +specify a zone, it will put, it will search only in zone, + +1290 +01:03:27,070 --> 01:03:29,971 +so you can limit your search and be more efficient, okay, + +1291 +01:03:29,973 --> 01:03:33,408 +if you can sensibly Divide your database into little + +1292 +01:03:33,410 --> 01:03:36,678 +zones. To keep your searches smaller it's a good idea. + +1293 +01:03:36,680 --> 01:03:38,180 +That's what that inZoneWithID is. + +1294 +01:03:38,182 --> 01:03:40,115 +For your final project, again you could say nil and + +1295 +01:03:40,117 --> 01:03:43,752 +just put everything in one big zone, default zone. And + +1296 +01:03:43,754 --> 01:03:46,121 +then of course you're gonna call a completion handler, and + +1297 +01:03:46,123 --> 01:03:47,789 +look what the completion handler has. + +1298 +01:03:47,791 --> 01:03:51,126 +An array of the records that you searched for, couldn't be + +1299 +01:03:51,128 --> 01:03:55,330 +simpler. Okay? Possibly an error. Okay, so this is just + +1300 +01:03:55,332 --> 01:03:57,732 +really straightforward. You give it a query. + +1301 +01:03:57,734 --> 01:04:00,802 +It just calls your handler with the records that matched. + +1302 +01:04:00,804 --> 01:04:03,638 +Or nil if there was an error, okay? + +1303 +01:04:03,640 --> 01:04:07,309 +Now what about this CKQuery, that's also trivial. + +1304 +01:04:07,311 --> 01:04:10,078 +It's initializer is just the entity, okay? + +1305 +01:04:10,080 --> 01:04:14,549 +So you wanna search for tweets and then an NSPredicate, okay? + +1306 +01:04:14,551 --> 01:04:17,719 +And so this NSPredicate is gonna specify which things you + +1307 +01:04:17,721 --> 01:04:21,423 +want in your database. And this NSPredicate is + +1308 +01:04:21,425 --> 01:04:24,726 +obviously much simpler than Core Data because there + +1309 +01:04:24,728 --> 01:04:28,430 +are just fewer things that you can do, fewer data type, + +1310 +01:04:28,432 --> 01:04:31,900 +fewer, the relationships aren't as complicated, + +1311 +01:04:31,902 --> 01:04:35,604 +there's just that reference thing etc. But + +1312 +01:04:35,606 --> 01:04:37,672 +you can look in the documentation for CKQuery, + +1313 +01:04:37,674 --> 01:04:40,976 +it has a very good description of all the things you can do + +1314 +01:04:40,978 --> 01:04:43,278 +with NSPredicate for CKQuery. It's, you know, + +1315 +01:04:43,280 --> 01:04:46,114 +all the things you might think like equals equals. + +1316 +01:04:46,116 --> 01:04:48,650 +But also it has some cool things like in, okay? + +1317 +01:04:48,652 --> 01:04:50,352 +Where you check whether something is in and + +1318 +01:04:50,354 --> 01:04:53,588 +array of other things for example. And so like that, + +1319 +01:04:53,590 --> 01:04:56,725 +it also has a special field name by the way, self, and + +1320 +01:04:56,727 --> 01:04:59,327 +you know, cuz you should, could have a field name like + +1321 +01:04:59,329 --> 01:05:03,265 +text if there's a tweet, text contains some word. + +1322 +01:05:03,267 --> 01:05:05,834 +That's perfectly valid predicate. But you can also + +1323 +01:05:05,836 --> 01:05:09,604 +have self as a keyword, not just tech, but self. And if I + +1324 +01:05:09,606 --> 01:05:13,541 +say self contains whatever, it'll look in all the fields, + +1325 +01:05:13,543 --> 01:05:16,978 +okay, that are index, not just text but all the tweets. + +1326 +01:05:16,980 --> 01:05:20,248 +So maybe you have a tweet that has text, it has hashtags, + +1327 +01:05:20,250 --> 01:05:23,952 +it has you know URLs as different fields. If you'd say + +1328 +01:05:23,954 --> 01:05:26,922 +self-contained something, it'll look in all the fields, + +1329 +01:05:26,924 --> 01:05:28,523 +all the indexed fields to find it, okay? + +1330 +01:05:28,525 --> 01:05:33,528 +So it's kind of a search text over all the index field, + +1331 +01:05:33,530 --> 01:05:35,730 +okay? So this is really, couldn't be simpler, + +1332 +01:05:35,732 --> 01:05:38,333 +they couldn't have made this any simpler. This is as simple + +1333 +01:05:38,335 --> 01:05:41,136 +a kind of queries you can possibly imagine. Okay, so + +1334 +01:05:41,138 --> 01:05:43,371 +here's an example. Here I'm looking for + +1335 +01:05:43,373 --> 01:05:46,741 +a tweet that's text contains some search string so + +1336 +01:05:46,743 --> 01:05:47,742 +I've a predicate which is + +1337 +01:05:47,744 --> 01:05:51,479 +text contains %@ which is the search string there. + +1338 +01:05:51,481 --> 01:05:54,549 +Otherwise, it looks just like NSPredicate of core data. + +1339 +01:05:54,551 --> 01:05:57,018 +Okay, I'm gonna create this query which is looking for + +1340 +01:05:57,020 --> 01:06:00,422 +Tweets without predicate. I'm gonna perform the query + +1341 +01:06:00,424 --> 01:06:04,159 +some time later. It's gonna call my closure right here. + +1342 +01:06:04,161 --> 01:06:07,629 +It's gonna give me a list of all the Tweets, okay, + +1343 +01:06:07,631 --> 01:06:10,598 +that contain that. That's what this records thing is right + +1344 +01:06:10,600 --> 01:06:13,969 +here. Again, I'm checking for errors. Here, I've checked for + +1345 +01:06:13,971 --> 01:06:17,939 +that not authenticated error again. But, + +1346 +01:06:17,941 --> 01:06:22,143 +it's as simple as that, okay? Now, + +1347 +01:06:22,145 --> 01:06:25,146 +one thing, if you're gonna search on any of these things, + +1348 +01:06:25,148 --> 01:06:28,116 +any field that you're gonna search on, make sure you go to + +1349 +01:06:28,118 --> 01:06:30,986 +your dashboard and make sure that the checkbox query for + +1350 +01:06:30,988 --> 01:06:34,856 +indexes is set, otherwise you can't query on it. Okay, + +1351 +01:06:34,858 --> 01:06:38,159 +now when you create new fields automatically on + +1352 +01:06:38,161 --> 01:06:40,128 +the fly like this, it automatically sets those. + +1353 +01:06:40,130 --> 01:06:42,430 +it automatically turns on indexes for all of them. + +1354 +01:06:42,432 --> 01:06:44,966 +It doesn't turn on the indexes for created by and + +1355 +01:06:44,968 --> 01:06:47,736 +created date and all that, but it does do it for + +1356 +01:06:47,738 --> 01:06:51,106 +the new field that you add. And in fact, + +1357 +01:06:51,108 --> 01:06:52,440 +when you go to deploy, you probably wanna turn + +1358 +01:06:52,442 --> 01:06:54,843 +some of those off if you know you never search on it. + +1359 +01:06:54,845 --> 01:06:59,047 +Don't waste the database's time creating indexes that + +1360 +01:06:59,049 --> 01:07:03,018 +it doesn't use. Now, there's a special kind of record + +1361 +01:07:03,020 --> 01:07:06,354 +though that you get with the special method here which + +1362 +01:07:06,356 --> 01:07:10,392 +is the recordID of the user, okay, the currently logged in + +1363 +01:07:10,394 --> 01:07:12,460 +iCloud user. Now why would you ever want this? + +1364 +01:07:12,462 --> 01:07:14,662 +Well, because you might wanna look in the database and + +1365 +01:07:14,664 --> 01:07:17,632 +find records created by that user. And to do that, + +1366 +01:07:17,634 --> 01:07:21,169 +you need the user. You need the user's RecordID so + +1367 +01:07:21,171 --> 01:07:24,706 +that you can make a query that says user, or + +1368 +01:07:24,708 --> 01:07:28,309 +createdBy, let's say, which is a built in one. User, creator, + +1369 +01:07:28,311 --> 01:07:30,445 +something. Actually I'll talk about in the next slide. You + +1370 +01:07:30,447 --> 01:07:32,881 +want to be able to set that. Well, to do that, you need it. + +1371 +01:07:32,883 --> 01:07:35,216 +And you do this with a fetchUserRecordIDWithCompleti- + +1372 +01:07:35,218 --> 01:07:38,520 +onHandler. That is not sent to the database, though. + +1373 +01:07:38,522 --> 01:07:40,488 +That is sent to the container. Okay, + +1374 +01:07:40,490 --> 01:07:43,691 +because the container, all the databases in the container, + +1375 +01:07:43,693 --> 01:07:46,528 +the, I currently logged in iCloud user, is the user for + +1376 +01:07:46,530 --> 01:07:50,498 +them. So you actually go up to CKContainer to do this, + +1377 +01:07:50,500 --> 01:07:51,699 +CKContainer default container, + +1378 +01:07:51,701 --> 01:07:54,736 +fetch record user record with completion handler, and + +1379 +01:07:54,738 --> 01:07:57,372 +it just returns you the RecordID of the user. + +1380 +01:07:57,374 --> 01:08:00,842 +Now, notice this is the RecordID, not the CKRecord, + +1381 +01:08:00,844 --> 01:08:03,912 +you almost never need the actual record of the user. + +1382 +01:08:03,914 --> 01:08:05,380 +You could get the record of the user, and + +1383 +01:08:05,382 --> 01:08:07,348 +you could even add fields to it if you wanted, + +1384 +01:08:07,350 --> 01:08:10,485 +but it's rare to do that. Usually, you just need + +1385 +01:08:10,487 --> 01:08:13,621 +the RecordID because you're going to be querying on it, + +1386 +01:08:13,623 --> 01:08:17,125 +you're gonna be making queries to find out if this user was + +1387 +01:08:17,127 --> 01:08:19,828 +the person who created it or whatever, okay? + +1388 +01:08:19,830 --> 01:08:22,797 +The RecordID has a property record name, + +1389 +01:08:22,799 --> 01:08:26,935 +which is just some randomly created string that you + +1390 +01:08:26,937 --> 01:08:29,270 +can use as kind of a blind username. + +1391 +01:08:29,272 --> 01:08:31,973 +It's not gonna be the person's actual iCloud name, it's just + +1392 +01:08:31,975 --> 01:08:35,877 +some gobbledygook. But inside of your implementation, + +1393 +01:08:35,879 --> 01:08:40,048 +you can use it as a string key that means this user if you + +1394 +01:08:40,050 --> 01:08:43,818 +want, okay? I'm gonna combine the two things, + +1395 +01:08:43,820 --> 01:08:48,356 +the fetchUserRecord with the query here. I'm gonna find all + +1396 +01:08:48,358 --> 01:08:51,493 +the tweets that were created by the currently logged in + +1397 +01:08:51,495 --> 01:08:55,630 +user. Okay, so first I get the container, + +1398 +01:08:55,632 --> 01:08:58,800 +I fetch the user in the completion handler for + +1399 +01:08:58,802 --> 01:09:01,903 +that right here. I have the user. Now I'm gonna create + +1400 +01:09:01,905 --> 01:09:05,540 +a new predicate which is the creatorUserRecordID. + +1401 +01:09:05,542 --> 01:09:09,711 +Which is a built in field on all record types. + +1402 +01:09:09,713 --> 01:09:14,616 +Equals the UserRecordID, a thing I got from fetchRecord. + +1403 +01:09:14,618 --> 01:09:15,416 +See that thing right there. + +1404 +01:09:15,418 --> 01:09:17,619 +And them I'm gonna create a query which is for + +1405 +01:09:17,621 --> 01:09:20,155 +tweets that uses that predicate. Now I'm gonna + +1406 +01:09:20,157 --> 01:09:22,991 +get the public database and perform the query, okay? + +1407 +01:09:22,993 --> 01:09:26,761 +In zone nil, and I'm gonna get the record in error as + +1408 +01:09:26,763 --> 01:09:29,764 +a return value. And so now I have this records containing + +1409 +01:09:29,766 --> 01:09:32,767 +all the tweets created by the currently logged in user. + +1410 +01:09:32,769 --> 01:09:34,602 +See how I chained those two? And + +1411 +01:09:34,604 --> 01:09:37,872 +remember, this fetch record, UserRecordID, + +1412 +01:09:37,874 --> 01:09:38,606 +that's gonna take a little while. + +1413 +01:09:38,608 --> 01:09:41,109 +And when it returns, it's gonna do another query. + +1414 +01:09:41,111 --> 01:09:44,045 +That's gonna take a little while, so it's gonna chain. + +1415 +01:09:44,047 --> 01:09:47,549 +But since this call is inside of this other closure, + +1416 +01:09:47,551 --> 01:09:52,253 +it chains them nicely there. Okay, again + +1417 +01:09:52,255 --> 01:09:55,423 +you have to create, turn that Created By metadata index on + +1418 +01:09:55,425 --> 01:09:57,792 +that I showed you right at the beginning for this to work or + +1419 +01:09:57,794 --> 01:10:03,198 +you can't search on user. Okay, by the way, + +1420 +01:10:03,200 --> 01:10:06,901 +if you ever have a RecordID and you wanna get the record, + +1421 +01:10:06,903 --> 01:10:09,637 +okay, the CKRecord, you can use databases + +1422 +01:10:09,639 --> 01:10:12,240 +fetchRecordWithID and that will search and + +1423 +01:10:12,242 --> 01:10:16,311 +get the actual record, okay? The RecordID, though, + +1424 +01:10:16,313 --> 01:10:18,846 +on its own has some interesting things + +1425 +01:10:18,848 --> 01:10:22,850 +like the creator, the creation date, the record type, + +1426 +01:10:22,852 --> 01:10:26,321 +and all that stuff, so that's kind of fun. All right, + +1427 +01:10:26,323 --> 01:10:30,158 +deleting records from the database couldn't be easier. + +1428 +01:10:30,160 --> 01:10:30,658 +Just say to the database, + +1429 +01:10:30,660 --> 01:10:33,361 +deleteRecordWithID. You have to have the record ID, you can + +1430 +01:10:33,363 --> 01:10:35,230 +of course get the record ID from a record easily, + +1431 +01:10:35,232 --> 01:10:38,066 +there's a bar for it. And then completionHandler when it's + +1432 +01:10:38,068 --> 01:10:42,237 +done, okay? Okay, now let's talk about references, okay? + +1433 +01:10:42,239 --> 01:10:44,038 +I wanna, I want to store a reference. So this is + +1434 +01:10:44,040 --> 01:10:46,908 +like the Twitter user as the tweeter for a tweet. + +1435 +01:10:46,910 --> 01:10:50,278 +You cannot do this code right here. twitterUser equals + +1436 +01:10:50,280 --> 01:10:54,549 +a recordType TwitterUser. Tweet equals a record Tweet. + +1437 +01:10:54,551 --> 01:10:58,052 +Tweet, subTweeter equals TwitterUser. [SOUND] Okay, + +1438 +01:10:58,054 --> 01:11:02,490 +can't do it. This thing has to be a CKReference. + +1439 +01:11:02,492 --> 01:11:04,993 +So you just have to say TweetSubTweeter equals + +1440 +01:11:04,995 --> 01:11:07,996 +CKReference with the record. And then you specify this + +1441 +01:11:07,998 --> 01:11:10,431 +action which is interesting, it's either deletes itself or + +1442 +01:11:10,433 --> 01:11:16,504 +not. This action says what to do if this thing is deleted. + +1443 +01:11:16,506 --> 01:11:20,308 +Okay, when we cascade. So if I say the action is DeleteSelf, + +1444 +01:11:20,310 --> 01:11:23,811 +this reference to twitterUser is DeleteSelf reference. + +1445 +01:11:23,813 --> 01:11:26,948 +Then if the twitterUser is deleted, then the Tweet is + +1446 +01:11:26,950 --> 01:11:29,984 +deleted as well. It cascades the delete. That's why it's + +1447 +01:11:29,986 --> 01:11:35,089 +saying delete myself, okay, if this reference gets deleted. + +1448 +01:11:35,091 --> 01:11:37,525 +None means don't do it. When you delete, + +1449 +01:11:37,527 --> 01:11:41,829 +don't do any cascading, just delete this one thing, okay? + +1450 +01:11:41,831 --> 01:11:44,399 +By the way, when you're creating a predicate, + +1451 +01:11:44,401 --> 01:11:45,900 +you don't have to do that CKReference thing. + +1452 +01:11:45,902 --> 01:11:47,969 +If I wanna create a predicate which is tweeter equals + +1453 +01:11:47,971 --> 01:11:50,938 +something, I can actually pass the twitterUser, I don't have + +1454 +01:11:50,940 --> 01:11:56,978 +to say CKReference twitterUser there. Okay, standing queries, + +1455 +01:11:56,980 --> 01:12:00,315 +the last thing we're talking about, subscriptions, okay? So + +1456 +01:12:00,317 --> 01:12:02,950 +sometimes it's nice to not have to be constantly + +1457 +01:12:02,952 --> 01:12:06,454 +querying, you just want iCloud to tell you when a new Thing + +1458 +01:12:06,456 --> 01:12:09,657 +appears in the database that you're interested in. + +1459 +01:12:09,659 --> 01:12:12,794 +And that's really, really easy to do. So for + +1460 +01:12:12,796 --> 01:12:15,596 +an example here, I'm going to set up a subscription so + +1461 +01:12:15,598 --> 01:12:18,866 +that I get notified by a push notification any time that + +1462 +01:12:18,868 --> 01:12:19,600 +a Tweet is created or + +1463 +01:12:19,602 --> 01:12:22,737 +deleted. So I'm gonna create a predicate which is + +1464 +01:12:22,739 --> 01:12:25,373 +true predicate which means all Tweets. Okay, + +1465 +01:12:25,375 --> 01:12:28,009 +this is a special predicate, that means all. + +1466 +01:12:28,011 --> 01:12:31,145 +And in core dating, you have the predicate nil, means all. + +1467 +01:12:31,147 --> 01:12:32,814 +Here you have to create a predicate, + +1468 +01:12:32,816 --> 01:12:33,147 +it's true predicate. + +1469 +01:12:33,149 --> 01:12:36,084 +And then you create this thing called a CKSubscription + +1470 +01:12:36,086 --> 01:12:39,120 +with the record type that you're interested in, Tweets, + +1471 +01:12:39,122 --> 01:12:42,657 +the predicate you want, all of the them. A subscriptionID, + +1472 +01:12:42,659 --> 01:12:45,893 +this is an English language string that should + +1473 +01:12:45,895 --> 01:12:48,996 +very uniquely describe what you're looking for. Okay, + +1474 +01:12:48,998 --> 01:12:51,833 +because this is gonna identify this subscription in + +1475 +01:12:51,835 --> 01:12:54,335 +the database so you can delete it later for an example. + +1476 +01:12:54,337 --> 01:12:57,939 +Okay so here I called it "All Tweet Creation and Deletion". + +1477 +01:12:57,941 --> 01:13:02,510 +And then options is what kinds of actions of those tweets, + +1478 +01:13:02,512 --> 01:13:05,446 +for example, do you wanna know when the tweets are created? + +1479 +01:13:05,448 --> 01:13:07,115 +Do you wanna know when tweets are deleted? + +1480 +01:13:07,117 --> 01:13:08,883 +You can also find out when tweets are updated, + +1481 +01:13:08,885 --> 01:13:12,019 +their fields change. And you can also have FiresOnce + +1482 +01:13:12,021 --> 01:13:15,289 +in here which means that this subscription only works once. + +1483 +01:13:15,291 --> 01:13:16,391 +It sends you one push notification and + +1484 +01:13:16,393 --> 01:13:20,128 +then gets deleted. Okay, so it's like a one time standing + +1485 +01:13:20,130 --> 01:13:23,564 +query. It also has this thing called a notifcationInfo. + +1486 +01:13:23,566 --> 01:13:25,466 +Okay, this is gonna send a push notification. + +1487 +01:13:25,468 --> 01:13:28,536 +So this can help you configure that push notification right + +1488 +01:13:28,538 --> 01:13:32,039 +here. And then you just say, database.saveSubscription. + +1489 +01:13:32,041 --> 01:13:34,208 +Okay, and it'll call you back when it's done. + +1490 +01:13:34,210 --> 01:13:36,110 +And that puts this subscription in the database. + +1491 +01:13:36,112 --> 01:13:39,580 +And now the database is gonna send you a push notification + +1492 +01:13:39,582 --> 01:13:42,884 +whenever this is changing. Okay, creation or deletion of + +1493 +01:13:42,886 --> 01:13:46,254 +tweets, in this case. Okay, now I have to tell you how to + +1494 +01:13:46,256 --> 01:13:49,624 +deal with push notifications, okay. How to turn them on, + +1495 +01:13:49,626 --> 01:13:53,761 +and how to get them. So, to turn on a push notification, + +1496 +01:13:53,763 --> 01:13:56,030 +you actually need to in your application, + +1497 +01:13:56,032 --> 01:13:59,333 +didFinishLaunchingWithOptions is usually where you would put + +1498 +01:13:59,335 --> 01:14:02,003 +this code, you have to put these yellow lines here. + +1499 +01:14:02,005 --> 01:14:04,939 +Which is, you have to call this method + +1500 +01:14:04,941 --> 01:14:06,908 +registerUserNotificationSetti- ngs. + +1501 +01:14:06,910 --> 01:14:09,844 +Okay, the user notification settings just say what kind + +1502 +01:14:09,846 --> 01:14:13,714 +of push notifications you're willing to receive like, + +1503 +01:14:13,716 --> 01:14:16,150 +alerts, badges, or sounds. + +1504 +01:14:16,152 --> 01:14:19,220 +If you're just alerting to let the code know, you don't have + +1505 +01:14:19,222 --> 01:14:21,989 +to send off any of those three, okay? Alert badge and + +1506 +01:14:21,991 --> 01:14:24,425 +sound means it's gonna put an alert up when things come, + +1507 +01:14:24,427 --> 01:14:27,562 +okay, or a badge. It's gonna put a little red badge + +1508 +01:14:27,564 --> 01:14:30,331 +on your icon, your app icon which is kinda cool maybe, + +1509 +01:14:30,333 --> 01:14:32,033 +you might want that actually. + +1510 +01:14:32,035 --> 01:14:36,270 +You get to specify the, what happens when the push + +1511 +01:14:36,272 --> 01:14:39,073 +notification comes from Cloud Kit back in that notification + +1512 +01:14:39,075 --> 01:14:41,776 +info thing that I was telling you about in the previous + +1513 +01:14:41,778 --> 01:14:43,644 +slide. Subscription.notificationInfo, + +1514 +01:14:43,646 --> 01:14:46,981 +one of the things in there is whether to alert badge or + +1515 +01:14:46,983 --> 01:14:51,052 +sound when the subscription fires. Okay. So + +1516 +01:14:51,054 --> 01:14:54,622 +anyway you register what your kind of settings you want, and + +1517 +01:14:54,624 --> 01:14:56,791 +then you have to register for remote notifications. + +1518 +01:14:56,793 --> 01:14:59,327 +That means I wanna hear about remote notifications. + +1519 +01:14:59,329 --> 01:15:00,728 +If you don't do this, you won't get any push + +1520 +01:15:00,730 --> 01:15:04,298 +notifications of any kind, let alone these Cloud Kit ones. + +1521 +01:15:04,300 --> 01:15:06,634 +Okay. So now once you've done that okay, + +1522 +01:15:06,636 --> 01:15:08,936 +you need to receive them. And you do that with this + +1523 +01:15:08,938 --> 01:15:12,673 +application delegate method didReceiveRemoteNotification. + +1524 +01:15:12,675 --> 01:15:15,376 +So this will get called any time a push notification comes + +1525 +01:15:15,378 --> 01:15:19,380 +to your app, okay. When you get it there's user info + +1526 +01:15:19,382 --> 01:15:22,950 +right here, okay. And inside that userInfo is a dictionary + +1527 +01:15:22,952 --> 01:15:26,587 +that Cloud Kit's gonna send. And you're gonna use this + +1528 +01:15:26,589 --> 01:15:30,658 +CKNotification class, right here, call it initializer, + +1529 +01:15:30,660 --> 01:15:34,195 +with that dictionary to create a CKNotification. + +1530 +01:15:34,197 --> 01:15:37,532 +That CKNotification, Cloud Kit notification, represents + +1531 +01:15:37,534 --> 01:15:40,001 +the push notification that was sent to you. It's got all the + +1532 +01:15:40,003 --> 01:15:43,104 +information you need to know about the push notification + +1533 +01:15:43,106 --> 01:15:46,574 +that got sent because you're subscription. Okay? And + +1534 +01:15:46,576 --> 01:15:49,176 +it's got things in there like the recordID that change + +1535 +01:15:49,178 --> 01:15:53,748 +that cause it. Why the notification is happening s + +1536 +01:15:53,750 --> 01:15:54,782 +it because something was created, + +1537 +01:15:54,784 --> 01:15:56,717 +or something was deleted, or something was updated? + +1538 +01:15:56,719 --> 01:15:59,687 +Okay, will tell you which of those things went on that + +1539 +01:15:59,689 --> 01:16:02,790 +caused this notification to be sent to you and + +1540 +01:16:02,792 --> 01:16:04,258 +which record was affected by it. + +1541 +01:16:04,260 --> 01:16:07,094 +You can even, in the subscription notificationInfo, + +1542 +01:16:07,096 --> 01:16:10,031 +you can set certain fields to be prefetched and + +1543 +01:16:10,033 --> 01:16:12,733 +come along with. Okay, cuz normally it only sends you + +1544 +01:16:12,735 --> 01:16:15,269 +the recordID of what changed in the database. + +1545 +01:16:15,271 --> 01:16:16,938 +You might wanna actually sum of the fields, so + +1546 +01:16:16,940 --> 01:16:20,675 +you don't have to go get, fetch the record itself, okay? + +1547 +01:16:20,677 --> 01:16:23,477 +So that's great. Now that you've got this notification, + +1548 +01:16:23,479 --> 01:16:27,181 +what do you do with it. Okay, you really need to get it + +1549 +01:16:27,183 --> 01:16:29,750 +to the part of your UI, if you control it or + +1550 +01:16:29,752 --> 01:16:33,287 +whatever, that's going to do something with this data + +1551 +01:16:33,289 --> 01:16:35,756 +that has changed, okay. And the best way, + +1552 +01:16:35,758 --> 01:16:37,425 +this is all coming to your AppDelegate, right? + +1553 +01:16:37,427 --> 01:16:39,694 +Is your AppDelegate getting this push notification? + +1554 +01:16:39,696 --> 01:16:41,829 +That's not that useful because usually it's some view + +1555 +01:16:41,831 --> 01:16:44,265 +controller somewhere that really wants the information. + +1556 +01:16:44,267 --> 01:16:46,734 +So what we're gonna do is we're gonna forward it + +1557 +01:16:46,736 --> 01:16:49,770 +using the radio station model, okay? + +1558 +01:16:49,772 --> 01:16:52,106 +That's is real simple way to get this thing to came to + +1559 +01:16:52,108 --> 01:16:54,809 +AppDelegate and get it out to who really wants it. So + +1560 +01:16:54,811 --> 01:16:57,078 +I'm just gonna create a local notification here I'm gonna + +1561 +01:16:57,080 --> 01:16:59,880 +become a radio station broadcaster see in this + +1562 +01:16:59,882 --> 01:17:00,047 +notification. + +1563 +01:17:00,049 --> 01:17:03,417 +Here's my radio station name MyCloudKitNotificationName or + +1564 +01:17:03,419 --> 01:17:07,388 +whatever. Self is this is in AppDelegate so self is gonna + +1565 +01:17:07,390 --> 01:17:09,790 +be my AppDelegate but it probably doesn't matter what I + +1566 +01:17:09,792 --> 01:17:12,393 +pass here as the sender of the radio station. And + +1567 +01:17:12,395 --> 01:17:15,863 +then here in the userInfo, I'm gonna put that ckn, + +1568 +01:17:15,865 --> 01:17:18,666 +this notification right here that I created, okay, + +1569 +01:17:18,668 --> 01:17:21,335 +from the dictionary that came in the push notification. + +1570 +01:17:21,337 --> 01:17:23,704 +I'm gonna put that in the dictionary + +1571 +01:17:23,706 --> 01:17:25,873 +under some key name, ckn or + +1572 +01:17:25,875 --> 01:17:30,011 +whatever, CKNKey, so that the people who are listening to my + +1573 +01:17:30,013 --> 01:17:33,080 +radio station can get this CKNotification. By the way, + +1574 +01:17:33,082 --> 01:17:36,517 +these two strings wanna be global constant somewhere. + +1575 +01:17:36,519 --> 01:17:40,254 +So that the listeners and the sender are using the same keys + +1576 +01:17:40,256 --> 01:17:46,394 +and radio station names, okay? And then I just post it, okay. + +1577 +01:17:46,396 --> 01:17:48,329 +DefaultCenter postNotification disNotification. + +1578 +01:17:48,331 --> 01:17:51,098 +And now everybody's listening to this radio station gonna + +1579 +01:17:51,100 --> 01:17:52,967 +find out about all the push notifications coming + +1580 +01:17:52,969 --> 01:17:56,737 +from Cloud Kit. Cause they're getting forwarded out to them. + +1581 +01:17:56,739 --> 01:18:00,708 +Okay, now, if I'm an observer, what do I do? I just + +1582 +01:18:00,710 --> 01:18:04,111 +do this addObserverForName, okay. So now I'm some view + +1583 +01:18:04,113 --> 01:18:06,380 +controller that wants to hear this push notification, so + +1584 +01:18:06,382 --> 01:18:09,784 +I do addObserveForName, I use the radio station name there, + +1585 +01:18:09,786 --> 01:18:12,319 +I don't care who sends it to me, I'm going to do it on + +1586 +01:18:12,321 --> 01:18:14,889 +the same queue because I know my AppDelegate runs on + +1587 +01:18:14,891 --> 01:18:18,926 +the main queue, but I could put main queue here also. And + +1588 +01:18:18,928 --> 01:18:20,027 +then using block right here. + +1589 +01:18:20,029 --> 01:18:20,995 +This is the block that gets called. + +1590 +01:18:20,997 --> 01:18:24,432 +Here's the notification that came over the radio station. + +1591 +01:18:24,434 --> 01:18:26,467 +I'm gonna look in the notification look at that + +1592 +01:18:26,469 --> 01:18:30,905 +user interface, user info, get that key and cast it + +1593 +01:18:30,907 --> 01:18:34,608 +to be a CKQueryNotification by the way. There's another kind + +1594 +01:18:34,610 --> 01:18:39,113 +of thing it could be which is a zone oriented notification, + +1595 +01:18:39,115 --> 01:18:41,115 +I'm not talking about zones but most of the times it's + +1596 +01:18:41,117 --> 01:18:43,651 +gonna be a query notification cuz it's a subscription. + +1597 +01:18:43,653 --> 01:18:45,886 +So you can do this as query notification. + +1598 +01:18:45,888 --> 01:18:50,591 +Now you're gonna check to see if the subscriptionID of this + +1599 +01:18:50,593 --> 01:18:54,862 +query notification is the same as your subscriptionID because + +1600 +01:18:54,864 --> 01:18:56,230 +there might be other view controllers + +1601 +01:18:56,232 --> 01:18:57,698 +who have subscriptions in Cloud Kit and + +1602 +01:18:57,700 --> 01:18:59,700 +they're getting notified by push notifications. + +1603 +01:18:59,702 --> 01:19:02,002 +You don't want theirs, you want yours. And + +1604 +01:19:02,004 --> 01:19:04,839 +you can tell it's yours because you can look in this + +1605 +01:19:04,841 --> 01:19:08,275 +CKQueryNotification and find the subscriptionID that caused + +1606 +01:19:08,277 --> 01:19:12,046 +this push notification to get pushed, got it? And + +1607 +01:19:12,048 --> 01:19:15,249 +once I'm sure it's for me now I can go react to it. + +1608 +01:19:15,251 --> 01:19:15,416 +The data's available. + +1609 +01:19:15,418 --> 01:19:18,519 +Maybe I'll put it in my table view or whatever I do with + +1610 +01:19:18,521 --> 01:19:20,921 +it cuz the data is here, okay? Maybe I'll query for + +1611 +01:19:20,923 --> 01:19:24,959 +more information, whatever. But now I can get going. + +1612 +01:19:24,961 --> 01:19:28,262 +Make sense? By the way, notice that when did out observe for + +1613 +01:19:28,264 --> 01:19:31,198 +name I grabbed the return value that cookie I told you + +1614 +01:19:31,200 --> 01:19:34,468 +and in this object protocol thing we did and why do I want + +1615 +01:19:34,470 --> 01:19:37,271 +that, because later on when I'm done listening + +1616 +01:19:37,273 --> 01:19:40,641 +to further push notifications via this radio station. + +1617 +01:19:40,643 --> 01:19:44,278 +I'm gonna call removeObserver to remove this observer so + +1618 +01:19:44,280 --> 01:19:46,947 +I no longer get these local notifications. + +1619 +01:19:46,949 --> 01:19:51,051 +So this is something might do in our view did disappear. + +1620 +01:19:51,053 --> 01:19:54,922 +And we might do this in our view will appear or view did + +1621 +01:19:54,924 --> 01:19:58,192 +appear. Right, cuz only when we're on screen do we maybe + +1622 +01:19:58,194 --> 01:20:00,528 +want these notifications. When we go off we don't + +1623 +01:20:00,530 --> 01:20:01,796 +want them any more. When we come back on we wanna + +1624 +01:20:01,798 --> 01:20:06,500 +keep getting them again. Okay? You definitely wanna do this, + +1625 +01:20:06,502 --> 01:20:11,005 +by the way you never want your view controller to go away and + +1626 +01:20:11,007 --> 01:20:16,143 +still be here because this closure will keep your + +1627 +01:20:16,145 --> 01:20:18,746 +view controller in memory. And you don't wanna really do + +1628 +01:20:18,748 --> 01:20:21,282 +weakSelf and all that because you actually wanna explicitly + +1629 +01:20:21,284 --> 01:20:23,350 +remove it otherwise the NotificationCenter's gonna + +1630 +01:20:23,352 --> 01:20:27,555 +always be holding onto you, okay? + +1631 +01:20:27,557 --> 01:20:31,158 +So, make sure you do this, somewhere, removeObserver + +1632 +01:20:31,160 --> 01:20:33,828 +somewhere. Okay, that's it for Cloud Kit. Now you know + +1633 +01:20:33,830 --> 01:20:36,096 +everything about how to create records, query for + +1634 +01:20:36,098 --> 01:20:38,399 +them, and even sign up to get notified. + +1635 +01:20:38,401 --> 01:20:40,434 +I'm gonna do a big demo on this on Wednesday, so you can + +1636 +01:20:40,436 --> 01:20:45,172 +see it all in action. Friday, No Section again. Next week, + +1637 +01:20:45,174 --> 01:20:48,876 +still kinda deciding how or what works to do things. + +1638 +01:20:48,878 --> 01:20:49,743 +I really wanna make to sure you get + +1639 +01:20:49,745 --> 01:20:54,215 +this Segues covered right here but maps are also really cool. + +1640 +01:20:54,217 --> 01:20:56,450 +I won't get to all of these next week but I'll do as much + +1641 +01:20:56,452 --> 01:20:59,353 +as I can. Okay, if you have by the way something you really + +1642 +01:20:59,355 --> 01:21:01,355 +like to see me do because you find a project wants to + +1643 +01:21:01,357 --> 01:21:06,794 +do it. Like Cloud Kit was, let me know. Okay, that's it. + +1644 +01:21:06,796 --> 01:21:08,696 +See you next time. >> For + +1645 +01:21:08,698 --> 01:21:08,729 +more please visit us at stanford.edu. + diff --git a/subtitles/16. Notifications and CloudKit.srt b/subtitles/16. Notifications and CloudKit.srt new file mode 100644 index 0000000..11215d7 --- /dev/null +++ b/subtitles/16. Notifications and CloudKit.srt @@ -0,0 +1,4924 @@ +1 +00:00:00,001 --> 00:00:03,702 +[MUSIC] + +2 +00:00:03,704 --> 00:00:08,340 +Stanford University. >> All right, well, + +3 +00:00:08,342 --> 00:00:12,711 +welcome to C, Stanford CS193P spring of 2016 + +4 +00:00:12,713 --> 00:00:15,881 +lecture number 16. And today it's all demo. + +5 +00:00:15,883 --> 00:00:18,817 +I'm gonna do a big demo on CloudKit to show you how, + +6 +00:00:18,819 --> 00:00:21,286 +how that works. I'm also gonna take a brief little + +7 +00:00:21,288 --> 00:00:24,023 +thing at the beginning to show you about notifications, that + +8 +00:00:24,025 --> 00:00:27,092 +little radio station thing. We talked about how you can find + +9 +00:00:27,094 --> 00:00:28,427 +out about size changes happening and + +10 +00:00:28,429 --> 00:00:31,630 +I'm gonna show you how that works. And that's pretty much + +11 +00:00:31,632 --> 00:00:34,366 +it for today. It's kinda all demo today. + +12 +00:00:34,368 --> 00:00:37,870 +Coming up Friday we're not doing sections anymore. + +13 +00:00:37,872 --> 00:00:40,606 +People weren't that interested in sections this quarter, + +14 +00:00:40,608 --> 00:00:42,074 +that's fine. And then next week, + +15 +00:00:42,076 --> 00:00:44,977 +I'm gonna be covering maps some more segues, and + +16 +00:00:44,979 --> 00:00:48,680 +then just some miscellaneous topics, not quite sure yet + +17 +00:00:48,682 --> 00:00:52,317 +what I'm gonna do there. All right, so, + +18 +00:00:52,319 --> 00:00:57,356 +let's dive right into this demo. Going to launch Xcode + +19 +00:00:57,358 --> 00:01:02,127 +here. We're going to make a new project. + +20 +00:01:02,129 --> 00:01:04,630 +It's gonna be our standard stuff here. So + +21 +00:01:04,632 --> 00:01:08,667 +what I'm gonna do is an app that is a question asking app. + +22 +00:01:08,669 --> 00:01:12,604 +So it lets you author questions with answers, and + +23 +00:01:12,606 --> 00:01:14,807 +then they're out on the cloud, in iCloud, + +24 +00:01:14,809 --> 00:01:16,108 +and people can answer the questions, + +25 +00:01:16,110 --> 00:01:18,243 +okay, and then it keeps track of how many answers people had + +26 +00:01:18,245 --> 00:01:20,946 +and all that stuff. So today we're just gonna kinda do + +27 +00:01:20,948 --> 00:01:23,082 +the start of it, which is, we'll have some UI to make + +28 +00:01:23,084 --> 00:01:25,584 +the question and we'll upload the questions to the cloud, + +29 +00:01:25,586 --> 00:01:28,020 +and then we'll have another view controller which shows + +30 +00:01:28,022 --> 00:01:30,122 +a list of all the questions that you can choose on. + +31 +00:01:30,124 --> 00:01:33,325 +And you can click, some UI to make a new question or + +32 +00:01:33,327 --> 00:01:35,961 +delete old questions. So we're gonna be able to do all + +33 +00:01:35,963 --> 00:01:37,262 +kinds of iCloud stuff there. Deleting, + +34 +00:01:37,264 --> 00:01:39,998 +we're gonna do subscriptions with push notifications, + +35 +00:01:40,000 --> 00:01:45,070 +all that stuff. Okay, so we're gonna call this app Pollster. + +36 +00:01:45,072 --> 00:01:48,640 +I'm also gonna change my unique thing here just to be + +37 +00:01:48,642 --> 00:01:52,945 +something different, how about teacher instead of instructor. + +38 +00:01:52,947 --> 00:01:55,147 +So Pollster, because you could use it to poll, + +39 +00:01:55,149 --> 00:01:57,783 +ask people questions, and get polls. No Core Data, + +40 +00:01:57,785 --> 00:02:00,819 +it's gonna be an iPhone-only application. We're just gonna + +41 +00:02:00,821 --> 00:02:04,189 +have a couple table views is all. And we'll put it in our + +42 +00:02:04,191 --> 00:02:09,128 +standard location here. So here we are in Pollster, and + +43 +00:02:09,130 --> 00:02:14,433 +I'm going to kind of clear out my storyboard to start. So + +44 +00:02:14,435 --> 00:02:18,637 +let's take this little view controller that it + +45 +00:02:18,639 --> 00:02:22,941 +comes with, let's delete its code right here. + +46 +00:02:22,943 --> 00:02:26,445 +So I'll do Delete. Move that to the trash. + +47 +00:02:26,447 --> 00:02:29,948 +Let's go ahead and put these little guys into a little + +48 +00:02:29,950 --> 00:02:33,852 +supporting files thing again, Supporting Files. And notice + +49 +00:02:33,854 --> 00:02:36,054 +I'm gonna leave AppDelegate out of the Supporting Files, + +50 +00:02:36,056 --> 00:02:38,190 +because of course, we're gonna do push notifications. + +51 +00:02:38,192 --> 00:02:40,893 +That involves our AppDelegate, so it's not really + +52 +00:02:40,895 --> 00:02:43,862 +a supporting file, it's kind of a main thing this time. + +53 +00:02:43,864 --> 00:02:47,833 +And back in the storyboard we can just get rid of this view + +54 +00:02:47,835 --> 00:02:51,069 +controller, we don't need it at all, okay. + +55 +00:02:51,071 --> 00:02:52,905 +Now, I also have some other files + +56 +00:02:52,907 --> 00:02:55,307 +here that are gonna be supporting files for + +57 +00:02:55,309 --> 00:02:58,410 +this demo, so I'm gonna drag those in right here. + +58 +00:02:58,412 --> 00:03:00,979 +In fact, I'm gonna put them in Supporting Files. + +59 +00:03:00,981 --> 00:03:05,317 +Copy them in, let's take a quick look at those. + +60 +00:03:05,319 --> 00:03:08,687 +All right, so one is, I just wanted all my structs, with, + +61 +00:03:08,689 --> 00:03:11,456 +you know, my constants in there to be pre-typed in so + +62 +00:03:11,458 --> 00:03:14,593 +I don't have to type them in all the time. And basically, + +63 +00:03:14,595 --> 00:03:18,397 +these constants are gonna be for the push or actually for + +64 +00:03:18,399 --> 00:03:21,300 +the local notification, the radio station stuff, + +65 +00:03:21,302 --> 00:03:24,436 +this is gonna be the name of our radio station and + +66 +00:03:24,438 --> 00:03:25,537 +the key in the dictionary. + +67 +00:03:25,539 --> 00:03:27,406 +And then these are the names of the entities and + +68 +00:03:27,408 --> 00:03:29,675 +attributes that I'm gonna create in CloudKit, okay? + +69 +00:03:29,677 --> 00:03:32,311 +So we're doing QandA, here are questions and answers, and + +70 +00:03:32,313 --> 00:03:35,547 +here's a Response to a QandA, and then we've got questions, + +71 +00:03:35,549 --> 00:03:36,982 +answers, we got a chosenAnswer, and + +72 +00:03:36,984 --> 00:03:40,886 +then we've got a reference qanda. So we got all that. + +73 +00:03:40,888 --> 00:03:43,388 +And then I added this little wasCreatedByThisUser. + +74 +00:03:43,390 --> 00:03:46,225 +It's a bool on a CKRecord, a CloudKit record, that just + +75 +00:03:46,227 --> 00:03:49,027 +says whether this record was created by the currently + +76 +00:03:49,029 --> 00:03:52,097 +logged in iCloud user, okay. So that's that. + +77 +00:03:52,099 --> 00:03:55,300 +Then, over here, I have this nice class here, + +78 +00:03:55,302 --> 00:03:57,236 +QandATableViewController. + +79 +00:03:57,238 --> 00:04:00,205 +It is, has nothing to do with iCloud. It's just a table view + +80 +00:04:00,207 --> 00:04:03,775 +controller that shows a question, okay, a question and + +81 +00:04:03,777 --> 00:04:06,778 +as many answers as you want. Okay, notice that it inherits + +82 +00:04:06,780 --> 00:04:09,281 +from TextTableViewController. That's a generic + +83 +00:04:09,283 --> 00:04:12,284 +view controller that just shows a table view where all + +84 +00:04:12,286 --> 00:04:14,753 +the rows are editable text. Okay, that's all that is. + +85 +00:04:14,755 --> 00:04:17,055 +It doesn't know anything about questions and answers, + +86 +00:04:17,057 --> 00:04:17,856 +it's just rows of editable text, + +87 +00:04:17,858 --> 00:04:21,226 +nothing more. We're not even gonna be accessing this API, + +88 +00:04:21,228 --> 00:04:24,129 +we're gonna be focusing totally at this MVC's level. + +89 +00:04:24,131 --> 00:04:27,432 +And here's the public API for that, super simple. Okay, + +90 +00:04:27,434 --> 00:04:30,736 +it's got this var qanda, which is basically its model, + +91 +00:04:30,738 --> 00:04:33,305 +which is of type QandA, that's this struct, and + +92 +00:04:33,307 --> 00:04:35,874 +it's a question, which is a String, and answers, + +93 +00:04:35,876 --> 00:04:39,011 +which are Strings. Okay, so it couldn't be any simpler, + +94 +00:04:39,013 --> 00:04:41,313 +it's the simplest possible data structure for + +95 +00:04:41,315 --> 00:04:43,982 +a Q&A. It's got, these other vars here is just whether + +96 +00:04:43,984 --> 00:04:46,685 +you're asking the question or answering the question. + +97 +00:04:46,687 --> 00:04:47,886 +That's cuz if you're asking the question, + +98 +00:04:47,888 --> 00:04:50,289 +you can edit the question, right? You're asking it, so + +99 +00:04:50,291 --> 00:04:52,291 +you can add more answers and stuff like that. + +100 +00:04:52,293 --> 00:04:53,525 +Whereas, if you're answering the question, + +101 +00:04:53,527 --> 00:04:55,627 +you can only choose an answer, okay? And + +102 +00:04:55,629 --> 00:04:57,829 +then if you do choose an answer, here's the answer. + +103 +00:04:57,831 --> 00:05:01,700 +So you can just get the answer as a string, okay? It might be + +104 +00:05:01,702 --> 00:05:03,568 +a nil, because maybe they haven't answered yet. + +105 +00:05:03,570 --> 00:05:06,405 +So that's it, that's the entire public API of this, and + +106 +00:05:06,407 --> 00:05:09,007 +this is the only API we're gonna use in our cloud one. + +107 +00:05:09,009 --> 00:05:12,210 +And our cloud one is just gonna be a subclass of this, + +108 +00:05:12,212 --> 00:05:13,979 +because it's gonna be a QandA, but + +109 +00:05:13,981 --> 00:05:16,548 +it's a QandA that's stored in the cloud, okay. + +110 +00:05:16,550 --> 00:05:19,851 +So let's go ahead and create that subclass of this guy, so + +111 +00:05:19,853 --> 00:05:23,255 +I'm just gonna do File > New, okay, > Cocoa Touch Class. + +112 +00:05:23,257 --> 00:05:28,827 +It's gonna be a subclass of our QandATableViewController, + +113 +00:05:28,829 --> 00:05:33,398 +okay. And we're gonna call it CloudQand, whoops, + +114 +00:05:34,601 --> 00:05:36,068 +QandATableViewController, okay? + +115 +00:05:36,070 --> 00:05:39,004 +Cuz it's basically just a QandATableViewController that + +116 +00:05:39,006 --> 00:05:42,040 +stores its question and answer on the cloud. All right, so + +117 +00:05:42,042 --> 00:05:45,644 +here it is. Let's go ahead and blast all this, just so + +118 +00:05:45,646 --> 00:05:49,147 +you can clearly see what new stuff we're adding here. So + +119 +00:05:49,149 --> 00:05:52,351 +there's our super class being a QandATableViewController. + +120 +00:05:52,353 --> 00:05:54,753 +Let's, of course, go to our storyboard and + +121 +00:05:54,755 --> 00:05:56,722 +drag out a Table View Controller, okay. + +122 +00:05:56,724 --> 00:05:59,958 +And we're gonna set its identity to be one of these + +123 +00:05:59,960 --> 00:06:02,160 +CloudQandATableViewControll- ers. + +124 +00:06:02,162 --> 00:06:05,197 +What's interesting about the QandATableViewController is, + +125 +00:06:05,199 --> 00:06:07,566 +you don't need any prototype cells at all. + +126 +00:06:07,568 --> 00:06:09,601 +It creates its prototype cells in code. + +127 +00:06:09,603 --> 00:06:11,503 +And so, if you're interested in how to do that for your + +128 +00:06:11,505 --> 00:06:13,705 +final project or whatever, you could take a look at that + +129 +00:06:13,707 --> 00:06:15,207 +QandATableViewController, actually, + +130 +00:06:15,209 --> 00:06:17,142 +you would wanna look at the TextTableViewController, + +131 +00:06:17,144 --> 00:06:20,712 +the superclass one for how you might have a table view that + +132 +00:06:20,714 --> 00:06:23,348 +creates its cells that way instead of using prototypes. + +133 +00:06:23,350 --> 00:06:24,983 +And you can see why it don't use prototypes, + +134 +00:06:24,985 --> 00:06:26,518 +because it's such a simple cell, + +135 +00:06:26,520 --> 00:06:28,120 +its just has a text view in there, that's it. + +136 +00:06:28,122 --> 00:06:30,555 +The entire cell is just a text view, nothing more. + +137 +00:06:30,557 --> 00:06:32,290 +So it didn't really need a prototype to do that, + +138 +00:06:32,292 --> 00:06:33,558 +and it makes it easier for subclasser too, + +139 +00:06:33,560 --> 00:06:37,028 +they don't have to worry about that. All right, so + +140 +00:06:37,030 --> 00:06:37,295 +we've got our thing here. + +141 +00:06:37,297 --> 00:06:40,365 +Let's also make sure that it's the Initial View Controller, + +142 +00:06:40,367 --> 00:06:43,402 +right here, where we have the arrow coming in. And in fact, + +143 +00:06:43,404 --> 00:06:48,140 +I'm gonna put this thing into a Navigation Controller, okay? + +144 +00:06:48,142 --> 00:06:52,077 +That way I can have titles on things and stuff like that. + +145 +00:06:52,079 --> 00:06:54,246 +Okay, so this is our UI to start. And + +146 +00:06:54,248 --> 00:06:57,716 +we're gonna start by just having a question up here in + +147 +00:06:57,718 --> 00:07:01,720 +this cloud TableViewController right here. So I'm gonna go to + +148 +00:07:01,722 --> 00:07:04,322 +the cloud TableViewController. Where did I put that? + +149 +00:07:04,324 --> 00:07:06,391 +Right here. I'm gonna take that out of Supporting Files, + +150 +00:07:06,393 --> 00:07:09,661 +actually. So I'm gonna go to the cloud TableViewController, + +151 +00:07:09,663 --> 00:07:11,129 +and I'm just gonna, in its viewDidLoad, + +152 +00:07:11,131 --> 00:07:12,931 +I'm just gonna give it a question. Okay, so, + +153 +00:07:12,933 --> 00:07:15,467 +super.viewDidLoad, just so you can see how this thing works. + +154 +00:07:15,469 --> 00:07:20,839 +So qanda = a QandA, and here's the constructor for it. + +155 +00:07:20,841 --> 00:07:21,239 +It takes a question, you know, + +156 +00:07:21,241 --> 00:07:26,144 +"What is your favorite color?" or something like that. And + +157 +00:07:26,146 --> 00:07:29,915 +the answer is ["Blue", "Black", "Red"], + +158 +00:07:29,917 --> 00:07:34,753 +okay, or however many we want, okay? So let's just run and + +159 +00:07:34,755 --> 00:07:37,689 +see what that looks like. We'll go ahead and run I think + +160 +00:07:37,691 --> 00:07:42,027 +we'll run this on the device, actually. Let's try that. + +161 +00:07:50,804 --> 00:07:54,873 +Okay, so this is an iPad, but it's running here in iPhone + +162 +00:07:54,875 --> 00:07:58,043 +Compatibility mode, I'm still sharing an iPad. + +163 +00:07:58,045 --> 00:07:59,644 +So here you go, what is your favorite color? + +164 +00:07:59,646 --> 00:08:01,179 +It shows to you, you can scroll up and + +165 +00:08:01,181 --> 00:08:03,348 +down and you can choose an answer, okay? Now, + +166 +00:08:03,350 --> 00:08:06,318 +that's because we're in answering mode, okay? But + +167 +00:08:06,320 --> 00:08:11,590 +if we go back to our code over here and say asking = oops, + +168 +00:08:11,592 --> 00:08:14,559 +asking = true, okay, and then run, + +169 +00:08:14,561 --> 00:08:18,263 +you'll get very similar UI. The only difference being, + +170 +00:08:18,265 --> 00:08:20,966 +we can edit it. We can add more answers and + +171 +00:08:20,968 --> 00:08:22,667 +move our answers around. Okay, so here we go. + +172 +00:08:22,669 --> 00:08:26,371 +Notice that we can reposition them, okay, so if we want one + +173 +00:08:26,373 --> 00:08:29,307 +answer to be after another, we could add another answer here, + +174 +00:08:29,309 --> 00:08:34,145 +maybe white. Okay, something like that. We can delete + +175 +00:08:34,147 --> 00:08:38,416 +an answer just by backspacing out of it. Gets rid of it. + +176 +00:08:38,418 --> 00:08:41,653 +Okay, we can change the question too if wanted. Okay, + +177 +00:08:41,655 --> 00:08:43,955 +so everyone understand what this QandATableViewController + +178 +00:08:43,957 --> 00:08:46,525 +we just inherited from does? That it. That's all it does. + +179 +00:08:46,527 --> 00:08:48,226 +Okay, now, it knows nothing about the cloud. + +180 +00:08:48,228 --> 00:08:51,530 +And what we're gonna make this Q&A thing here be + +181 +00:08:51,532 --> 00:08:53,298 +stored on the cloud. All right, so + +182 +00:08:53,300 --> 00:08:56,268 +now we're back in the CloudQandATableViewController. + +183 +00:08:56,270 --> 00:08:59,304 +And we want to make this thing work with the cloud. So + +184 +00:08:59,306 --> 00:09:02,807 +it's gonna have a different model than its superclass. + +185 +00:09:02,809 --> 00:09:06,578 +Its superclass's model is a question and answer, which is + +186 +00:09:06,580 --> 00:09:11,016 +good, but our model here is going to be a CKRecord, okay, + +187 +00:09:11,018 --> 00:09:11,917 +a CloudKit record. + +188 +00:09:11,919 --> 00:09:15,053 +So I'm gonna call this thing CKQandA, + +189 +00:09:15,055 --> 00:09:18,957 +okay, called that because it's CloudKit Q&A. + +190 +00:09:18,959 --> 00:09:22,327 +Actually, maybe we can even call it CloudKitQandARecord so + +191 +00:09:22,329 --> 00:09:26,097 +we're clear that it's a record in CloudKit. And + +192 +00:09:26,099 --> 00:09:29,234 +it's gonna be a CKRecord, is all. And of course, + +193 +00:09:29,236 --> 00:09:32,470 +if anyone sets it, just like with almost all of our MVC's, + +194 +00:09:32,472 --> 00:09:34,372 +when someone sets our model to something, + +195 +00:09:34,374 --> 00:09:36,942 +if it's public and we allow people to set it, when we + +196 +00:09:36,944 --> 00:09:39,644 +set it, we want to react to that. And what we want to do + +197 +00:09:39,646 --> 00:09:42,047 +when someone sets our record is call our superclass, + +198 +00:09:42,049 --> 00:09:45,317 +set up our superclass's model, right, that QandA. We're gonna + +199 +00:09:45,319 --> 00:09:47,485 +get the question and answer out of the record and put, + +200 +00:09:47,487 --> 00:09:52,023 +set it up in our superclass. So we'll just let the question + +201 +00:09:52,025 --> 00:09:56,194 +equal the record's, and remember that we access + +202 +00:09:56,196 --> 00:10:00,465 +the records just using dictionary-like notation. + +203 +00:10:00,467 --> 00:10:04,836 +So I'm gonna use one of those constants that I had there, + +204 +00:10:04,838 --> 00:10:06,972 +Attribute.Question. Okay? + +205 +00:10:06,974 --> 00:10:10,342 +That's over here, remember, in the CloudKit extensions. + +206 +00:10:10,344 --> 00:10:15,180 +So Cloud.Attribute.Question is this key, so that's gonna + +207 +00:10:15,182 --> 00:10:19,084 +be a key into my QandA entity right here. Okay, and notice + +208 +00:10:19,086 --> 00:10:21,720 +how I'm not going and creating this scheme anywhere first, + +209 +00:10:21,722 --> 00:10:24,222 +I'm just writing my code on the fly, and it's just gonna + +210 +00:10:24,224 --> 00:10:26,558 +automatically create these things in the database for + +211 +00:10:26,560 --> 00:10:30,161 +me as I go. Now, we also know that this ckQandARecord, + +212 +00:10:30,163 --> 00:10:31,863 +when you use this dictionary notation, + +213 +00:10:31,865 --> 00:10:35,734 +it always returns this type that you have to cast, right. + +214 +00:10:35,736 --> 00:10:39,671 +It returns a CKRecord type or something like that. + +215 +00:10:39,673 --> 00:10:41,906 +So I'm gonna have to say as a String, cuz I know + +216 +00:10:41,908 --> 00:10:44,376 +the question is a string. And by the way, if that's nil, + +217 +00:10:44,378 --> 00:10:48,313 +I'm just gonna use an empty string as my question, okay? + +218 +00:10:48,315 --> 00:10:50,248 +So that way my question's never nil here. + +219 +00:10:50,250 --> 00:10:52,217 +And then it's similar with the answers, + +220 +00:10:52,219 --> 00:10:54,886 +that's the QandARecord, using the attribute for + +221 +00:10:54,888 --> 00:10:57,455 +the answers, except for, that's not a string, + +222 +00:10:57,457 --> 00:11:00,592 +it's an array of strings. And if that's nil, then we'll + +223 +00:11:00,594 --> 00:11:03,762 +use an empty array. So now I've gotten my question and + +224 +00:11:03,764 --> 00:11:06,731 +my answers out of this record that was given to me. + +225 +00:11:06,733 --> 00:11:10,402 +Okay, this is didSet on my public API right here. So now + +226 +00:11:10,404 --> 00:11:14,606 +I'm gonna have my superclass qanda equal a QandA, okay, + +227 +00:11:14,608 --> 00:11:18,576 +where the question is that question and the answers is + +228 +00:11:18,578 --> 00:11:24,049 +that answers. Okay? Now, what about the asking, + +229 +00:11:24,051 --> 00:11:25,917 +okay, what about whether I'm asking or not? + +230 +00:11:25,919 --> 00:11:28,086 +Okay, this thing of whether it's gonna be editable or + +231 +00:11:28,088 --> 00:11:30,822 +not. Well, that depends on whether this record they just + +232 +00:11:30,824 --> 00:11:33,491 +gave me was created by me. If it was created by me, them I'm + +233 +00:11:33,493 --> 00:11:35,326 +clearly editing it. It was created by someone else, + +234 +00:11:35,328 --> 00:11:39,731 +then I'm just choosing it. So I'm just gonna say that that + +235 +00:11:39,733 --> 00:11:45,270 +is ckQandARecord.wasCreated, what did I call it, + +236 +00:11:45,272 --> 00:11:50,909 +wasCreatedByThisUser, okay? So I'm just using that thing + +237 +00:11:50,911 --> 00:11:55,313 +I showed you in that, that little extension over here, + +238 +00:11:55,315 --> 00:11:56,915 +okay? So we've got this record, now, + +239 +00:11:56,917 --> 00:12:00,885 +a couple of problems here, okay? One thing is right here. + +240 +00:12:00,887 --> 00:12:05,590 +Use of undeclared type CKRecord. Why is that? import + +241 +00:12:05,592 --> 00:12:09,327 +CloudKit. Okay? CloudKit is a different framework. + +242 +00:12:09,329 --> 00:12:10,962 +If you want to use it in any of your files, + +243 +00:12:10,964 --> 00:12:13,765 +you have to import CloudKit, okay? Still have an error + +244 +00:12:13,767 --> 00:12:16,334 +here. What's this? The old no initializers. + +245 +00:12:16,336 --> 00:12:20,105 +Why? Because this is never initialized. Okay, well, + +246 +00:12:20,107 --> 00:12:22,974 +this is kind of an interesting case, because I could just, + +247 +00:12:22,976 --> 00:12:25,610 +for example, make this be an optional. + +248 +00:12:25,612 --> 00:12:29,380 +Then it would start out nil, that's great, but really, + +249 +00:12:29,382 --> 00:12:34,018 +I don't want any external person to be giving me + +250 +00:12:34,020 --> 00:12:36,721 +an empty record, you know, a nil record. So, + +251 +00:12:36,723 --> 00:12:38,890 +I'm gonna do something kind of interesting here that you can + +252 +00:12:38,892 --> 00:12:42,927 +do when you want your public API to be non-optional but + +253 +00:12:42,929 --> 00:12:44,596 +you still going to allow, + +254 +00:12:44,598 --> 00:12:48,166 +internally, the thing to be optional or nil. + +255 +00:12:48,168 --> 00:12:50,435 +Okay, what I'm gonna do is, I'm gonna leave this public + +256 +00:12:50,437 --> 00:12:54,105 +one to be optional, non-optional, rather. And + +257 +00:12:54,107 --> 00:12:59,911 +I'm gonna turn it into a get and set, okay, a computed one. + +258 +00:12:59,913 --> 00:13:04,315 +Where it's going to be implementing its get and + +259 +00:13:04,317 --> 00:13:09,387 +set by using a private var _ckQandARecord, and this + +260 +00:13:09,389 --> 00:13:13,057 +one's going to be optional. Okay, it's gonna do all + +261 +00:13:13,059 --> 00:13:15,627 +the same things that it did, it's just gonna be optional. + +262 +00:13:15,629 --> 00:13:18,396 +And in the get and set here, the set here is just going to + +263 +00:13:18,398 --> 00:13:23,968 +set the ckQandARecord private one to be the new value. + +264 +00:13:23,970 --> 00:13:25,270 +Okay, this is always gonna be non-optional, + +265 +00:13:25,272 --> 00:13:27,806 +that's going to be great, that's gonna set it there. And + +266 +00:13:27,808 --> 00:13:31,342 +here, if someone tries to get the ckQandARecord, + +267 +00:13:31,344 --> 00:13:36,214 +okay I'm gonna check to see if my private one is nil. + +268 +00:13:36,216 --> 00:13:40,185 +And if it is, I'm gonna set my private one to just be a blank + +269 +00:13:40,187 --> 00:13:46,558 +one. Okay, and here I'm gonna use this Entity.QandA. + +270 +00:13:46,560 --> 00:13:47,659 +Okay, so I'm gonna create a blank one. + +271 +00:13:47,661 --> 00:13:50,862 +And then I can return _ckQandA unwrapped, + +272 +00:13:50,864 --> 00:13:53,298 +cuz I know I always at least create it. + +273 +00:13:53,300 --> 00:13:56,201 +So this is kind of a little tricky thing here to make sure + +274 +00:13:56,203 --> 00:13:59,737 +that it's always this way. And another good thing about this + +275 +00:13:59,739 --> 00:14:02,473 +is, sorry, you had a question? >> Could you use + +276 +00:14:02,475 --> 00:14:05,710 +a lazy initializer here? >> Yeah, so the question is, + +277 +00:14:05,712 --> 00:14:07,045 +can I use a lazy initializer here? + +278 +00:14:07,047 --> 00:14:09,414 +Like, could I have said ckQandARecord = + +279 +00:14:09,416 --> 00:14:12,050 +CKRecord whatever, or even a lazy one, I wouldn't even have + +280 +00:14:12,052 --> 00:14:15,453 +to be lazy. The reason I'm not doing that is the old problem + +281 +00:14:15,455 --> 00:14:16,554 +where didSet doesn't + +282 +00:14:16,556 --> 00:14:21,092 +get called with the initializer, right? And + +283 +00:14:21,094 --> 00:14:22,827 +I want didSet to always get called, and + +284 +00:14:22,829 --> 00:14:25,263 +this is gonna cause didSet to always get called. + +285 +00:14:25,265 --> 00:14:28,233 +So it's a little bit of a trick there. Okay? + +286 +00:14:28,235 --> 00:14:31,502 +All right, so we've got this all set up for + +287 +00:14:31,504 --> 00:14:35,240 +our public API here. What do we want to do next? + +288 +00:14:35,242 --> 00:14:38,109 +Well, let's go ahead and change our viewDidLoad, + +289 +00:14:38,111 --> 00:14:40,245 +instead of setting our superclass thing, + +290 +00:14:40,247 --> 00:14:42,780 +let's just test and make sure we're working. So + +291 +00:14:42,782 --> 00:14:46,784 +I'm gonna set my ckQandARecord equal to an empty record, + +292 +00:14:46,786 --> 00:14:55,393 +just as a test here. Okay? So we're just gonna do that. + +293 +00:14:55,395 --> 00:15:00,231 +I just wanna see if this is working. So let's run. + +294 +00:15:00,233 --> 00:15:02,500 +And it should come up an empty question, but + +295 +00:15:02,502 --> 00:15:05,837 +it should be editable, because I created this CKRecord. + +296 +00:15:05,839 --> 00:15:08,640 +Right? So here it is. It's empty, empty question. + +297 +00:15:08,642 --> 00:15:12,277 +I could type here, you know, I could say something, you know, + +298 +00:15:12,279 --> 00:15:18,416 +like, When, we'll just say When, okay. Answers, Today. + +299 +00:15:18,418 --> 00:15:22,654 +Maybe Never, okay. + +300 +00:15:22,656 --> 00:15:27,659 +And then Tomorrow. Okay, so I've created this question. + +301 +00:15:27,661 --> 00:15:29,994 +Now, as I edit all this stuff, of course, + +302 +00:15:29,996 --> 00:15:31,763 +none of this is going on the cloud yet. + +303 +00:15:31,765 --> 00:15:34,565 +And in fact, none of it's even going into the CKRecord. + +304 +00:15:34,567 --> 00:15:37,535 +It's all just being held in that Q and A, okay. So + +305 +00:15:37,537 --> 00:15:40,004 +the next step we need to do is to have this thing + +306 +00:15:40,006 --> 00:15:43,374 +write to the cloud. Now, when to write to the cloud is + +307 +00:15:43,376 --> 00:15:46,344 +the question here, okay? We could add a button, + +308 +00:15:46,346 --> 00:15:48,746 +maybe a bar button item up there that says, + +309 +00:15:48,748 --> 00:15:51,416 +Save to Cloud, okay? Or just Save or something like that. + +310 +00:15:51,418 --> 00:15:54,986 +So that, that would be one way of it. But I'm actually kind + +311 +00:15:54,988 --> 00:15:58,489 +of a fan of UIs that the user doesn't have to take extra + +312 +00:15:58,491 --> 00:16:01,960 +steps unnecessarily. So wouldn't it be cool if we just + +313 +00:16:01,962 --> 00:16:05,697 +saved this to the cloud every time someone finishes + +314 +00:16:05,699 --> 00:16:06,397 +editing one of these fields. + +315 +00:16:06,399 --> 00:16:09,133 +Now as soon as the keyboard goes away, any of these times, + +316 +00:16:09,135 --> 00:16:11,569 +boom, we'll just save whatever we got to the cloud. + +317 +00:16:11,571 --> 00:16:15,239 +Now we might also want another UI which is published, + +318 +00:16:15,241 --> 00:16:16,341 +so that it shows it to other users. + +319 +00:16:16,343 --> 00:16:19,243 +But for now users can see things in progress, okay, + +320 +00:16:19,245 --> 00:16:21,212 +just because we're starting out our app. + +321 +00:16:21,214 --> 00:16:23,715 +So that's what I'm gonna do, I'm gonna have it every time + +322 +00:16:23,717 --> 00:16:26,751 +that this first responder gets taken away from a text field, + +323 +00:16:26,753 --> 00:16:28,319 +I'm gonna have it update the cloud. + +324 +00:16:28,321 --> 00:16:31,189 +So how can we find out when a first responder's taken away + +325 +00:16:31,191 --> 00:16:33,691 +from the text view? We gonna use the text view's delegate, + +326 +00:16:33,693 --> 00:16:36,160 +it's almost identical to the text field delegate + +327 +00:16:36,162 --> 00:16:39,630 +that we talked about before. And our super classes, okay, + +328 +00:16:39,632 --> 00:16:43,101 +the QandATableViewController, right here. + +329 +00:16:43,103 --> 00:16:46,237 +It's super class is the text TableViewController and + +330 +00:16:46,239 --> 00:16:50,108 +the text TableViewController already and not surprisingly, + +331 +00:16:50,110 --> 00:16:54,012 +is a UITextViewDelegate. So it's already receiving + +332 +00:16:54,014 --> 00:16:56,848 +UITextViewDelegate message whenever any of its text + +333 +00:16:56,850 --> 00:16:59,717 +views are edited. Okay, so that's great. So all we need + +334 +00:16:59,719 --> 00:17:02,553 +to do here is implement a UITextViewDelegate, so + +335 +00:17:02,555 --> 00:17:05,990 +I'm gonna implement the one which is DidEndEditing. + +336 +00:17:05,992 --> 00:17:08,593 +Okay, TextViewDidEndEditing. Whoops, + +337 +00:17:08,595 --> 00:17:13,431 +not did change. DidEndEditing, + +338 +00:17:13,433 --> 00:17:18,603 +this one. Okay, and let my super class. He might well be + +339 +00:17:18,605 --> 00:17:23,608 +doing something there so, we'll let him do his thing. + +340 +00:17:23,610 --> 00:17:27,245 +And now what I'm going to do with just update the Cloud, so + +341 +00:17:27,247 --> 00:17:30,448 +I'm going to have some method iCloud update, okay? + +342 +00:17:30,450 --> 00:17:33,584 +And it's complaining here because I overrode this so + +343 +00:17:33,586 --> 00:17:38,056 +I need to say override. Okay, so this iCloud update is going + +344 +00:17:38,058 --> 00:17:40,958 +to take our Q&A, ship it up to the iCloud, + +345 +00:17:40,960 --> 00:17:44,495 +to the cloud kit database up there. So let's go ahead and + +346 +00:17:44,497 --> 00:17:50,635 +do that. That's private func iCloud update. + +347 +00:17:50,637 --> 00:17:53,504 +Okay, so what do we need to do, to write this thing, + +348 +00:17:53,506 --> 00:17:55,406 +to the cloud? It's actually really simple. + +349 +00:17:55,408 --> 00:17:58,342 +The first thing we're gonna do is get the stuff out of our + +350 +00:17:58,344 --> 00:18:02,246 +QnA into our record. Then we're gonna save our record, + +351 +00:18:02,248 --> 00:18:05,450 +okay? So let's do the first part of that first. + +352 +00:18:05,452 --> 00:18:10,555 +Which is let's take our ckQandARecord, and set, + +353 +00:18:10,557 --> 00:18:13,191 +for example, its Question, and + +354 +00:18:13,193 --> 00:18:18,596 +we'll set this question equal to be the Q&A question. + +355 +00:18:18,598 --> 00:18:23,301 +So we're just grabbing it out of our super + +356 +00:18:23,303 --> 00:18:28,639 +classes thing and similarly here the Q&A for + +357 +00:18:28,641 --> 00:18:32,577 +the answers equals qanda.answers. + +358 +00:18:32,579 --> 00:18:35,980 +One thing, I'd probably don't wanna be polluting the cloud + +359 +00:18:35,982 --> 00:18:37,281 +with empty question and answers. + +360 +00:18:37,283 --> 00:18:40,551 +So I'm gonna put a little if around this just to say. + +361 +00:18:40,553 --> 00:18:44,856 +if my qanda, qanda.question, + +362 +00:18:44,858 --> 00:18:48,426 +oops, question.isEmpty and + +363 +00:18:48,428 --> 00:18:54,932 +I'm also goinna make sure that my answers, Q and + +364 +00:18:54,934 --> 00:18:59,637 +A answers isn't empty either, okay? + +365 +00:18:59,639 --> 00:19:02,507 +So, in other words, if I don't have an empty question or + +366 +00:19:02,509 --> 00:19:05,843 +answer, then I'll go ahead and do this. Okay, so now that + +367 +00:19:05,845 --> 00:19:09,547 +I've updated this record. I need to save it to the cloud. + +368 +00:19:09,549 --> 00:19:11,682 +So I'm gonna actually have a different function for that. + +369 +00:19:11,684 --> 00:19:14,285 +ICloudSaveRecord I'm gonna call it. + +370 +00:19:14,287 --> 00:19:18,089 +I'm gonna pass my CKQandARecord along. Okay, + +371 +00:19:18,091 --> 00:19:21,526 +we're gonna have this little function that's going to save + +372 +00:19:21,528 --> 00:19:27,198 +things to the cloud. So, private func iCloudSaveRecord, + +373 +00:19:27,200 --> 00:19:32,370 +takes a recordToSave, which is a CKRecord. Okay, + +374 +00:19:32,372 --> 00:19:35,907 +now what's this guy gonna do? This one also surprisingly + +375 +00:19:35,909 --> 00:19:38,576 +straightforward, as you saw from the slides. One thing + +376 +00:19:38,578 --> 00:19:41,279 +is any time we're gonna save something into the Cloud, + +377 +00:19:41,281 --> 00:19:42,947 +we need a database to work with. So + +378 +00:19:42,949 --> 00:19:48,085 +I'm gonna say private let the database equal CKcontainer, + +379 +00:19:48,087 --> 00:19:52,423 +remember? Container, whoops, [LAUGH] CKcontainer, + +380 +00:19:52,425 --> 00:19:56,060 +defaultContainer public. So we're gonna put this in + +381 +00:19:56,062 --> 00:19:58,129 +the public cloud because I want everyone to + +382 +00:19:58,131 --> 00:19:59,697 +see everyone else's questions, okay? + +383 +00:19:59,699 --> 00:20:02,133 +So if I put it in the private database I'd only be able to + +384 +00:20:02,135 --> 00:20:04,702 +see my own questions, so this way I can see everybody's, + +385 +00:20:04,704 --> 00:20:08,606 +okay? So we got that. So I'm gonna ask the database here, + +386 +00:20:08,608 --> 00:20:14,712 +just to save this record. Okay, the record to save. And + +387 +00:20:14,714 --> 00:20:17,515 +here's the completion handler right here. And in this + +388 +00:20:17,517 --> 00:20:21,519 +completions handler, we have the saved record basically. + +389 +00:20:21,521 --> 00:20:25,723 +Which should be the same thing or nil and the error, okay? + +390 +00:20:25,725 --> 00:20:28,526 +And this is asynchronous. Okay, this closure is gonna + +391 +00:20:28,528 --> 00:20:31,362 +be called sometime later when this thing is saved. + +392 +00:20:31,364 --> 00:20:33,564 +Now, this is a demo so I don't have time for + +393 +00:20:33,566 --> 00:20:36,300 +us to go and analyze every realistic error that could + +394 +00:20:36,302 --> 00:20:38,669 +happen every single time we do something with the cloud. + +395 +00:20:38,671 --> 00:20:40,838 +But I'm gonna show you a few of them just so + +396 +00:20:40,840 --> 00:20:43,574 +you kind of get an idea how to handle errors, what kind of + +397 +00:20:43,576 --> 00:20:46,210 +errors will come along. So let's look at an interesting + +398 +00:20:46,212 --> 00:20:49,313 +error that might happen when you're saving a record, okay. + +399 +00:20:49,315 --> 00:20:52,617 +So this error code equals + +400 +00:20:52,619 --> 00:20:59,790 +CKErrorCode.ServerRecordChan- ged. + +401 +00:20:59,792 --> 00:21:03,060 +Okay, don't forget .rawValue at the end because we're + +402 +00:21:03,062 --> 00:21:06,163 +looking at this as an right here. + +403 +00:21:06,165 --> 00:21:09,133 +So what is this error? This error means we tried to save + +404 +00:21:09,135 --> 00:21:12,303 +a record but that record had already been saved newer + +405 +00:21:12,305 --> 00:21:16,007 +by someone else, okay. So now I've got old data that I'm + +406 +00:21:16,009 --> 00:21:18,376 +trying to write on top of somebody who wrote newer data. + +407 +00:21:18,378 --> 00:21:20,811 +Maybe it was one of my other devices. Maybe it's even me. + +408 +00:21:20,813 --> 00:21:24,115 +Maybe I'm writing so fast. I saved three of four records in + +409 +00:21:24,117 --> 00:21:25,883 +a row, okay. They all got queued up and + +410 +00:21:25,885 --> 00:21:29,053 +one of them got through the network faster than the other, + +411 +00:21:29,055 --> 00:21:32,490 +could be. This kind of approach of writing things and + +412 +00:21:32,492 --> 00:21:34,892 +just checking when you write them to see + +413 +00:21:34,894 --> 00:21:37,194 +if it's newer is called optimistic locking. + +414 +00:21:37,196 --> 00:21:40,097 +Okay, it's basically you don't check first before you write, + +415 +00:21:40,099 --> 00:21:43,234 +you just try to write and it's newer you fail. Okay? + +416 +00:21:43,236 --> 00:21:47,204 +So save record which is this convenous method on database, + +417 +00:21:47,206 --> 00:21:50,775 +really has no way to make it overwrite, + +418 +00:21:50,777 --> 00:21:52,209 +have an older thing overwrite a newer thing. + +419 +00:21:52,211 --> 00:21:53,878 +It's not even clear that's what I'd want here. + +420 +00:21:53,880 --> 00:21:57,048 +I probably do want the newer thing, to be what what gets + +421 +00:21:57,050 --> 00:22:01,786 +through. If I did wanna do do overwriting of newer things, + +422 +00:22:01,788 --> 00:22:02,353 +then I can use that whole + +423 +00:22:02,355 --> 00:22:04,388 +operation-based thing I was telling you about in + +424 +00:22:04,390 --> 00:22:06,757 +the slides. Much more complicated that this + +425 +00:22:06,759 --> 00:22:09,794 +convenience method but it can be done. But anyway for server + +426 +00:22:09,796 --> 00:22:13,164 +record change happens there is really nothing we can do or + +427 +00:22:13,166 --> 00:22:16,600 +we would want to do. So you know we can just ignore this, + +428 +00:22:16,602 --> 00:22:21,072 +okay. We just assume that the newer ones is what we wanted. + +429 +00:22:21,074 --> 00:22:22,707 +Okay, what are the kind of stuff going to happen for + +430 +00:22:22,709 --> 00:22:28,379 +writing here? How about, let's say if our error is not Nil. + +431 +00:22:28,381 --> 00:22:28,579 +Well in other words, + +432 +00:22:28,581 --> 00:22:31,315 +we got some other kinds of error. Let's check to see + +433 +00:22:31,317 --> 00:22:34,485 +if that error may be has a retry in there for us. Okay, + +434 +00:22:34,487 --> 00:22:37,988 +something we can go and retry what we' re doing. Okay? Now, + +435 +00:22:37,990 --> 00:22:41,892 +maybe why does that happen? Net, network let, latencies, + +436 +00:22:41,894 --> 00:22:44,862 +something like that. Some network problem that might + +437 +00:22:44,864 --> 00:22:47,631 +recover with a little bit of time, that kind of thing. + +438 +00:22:47,633 --> 00:22:51,469 +So, how do we do this? So, I am just going to call another + +439 +00:22:51,471 --> 00:22:56,540 +function to handle this. I am gonna call it retry after + +440 +00:22:56,542 --> 00:23:00,444 +error. It's goinna take the error whatever happened and + +441 +00:23:00,446 --> 00:23:03,414 +I am just going to give it a selector to call to retry. + +442 +00:23:03,416 --> 00:23:06,016 +Okay, and the selector here is going to be in this case since + +443 +00:23:06,018 --> 00:23:09,253 +we are saving record. I'm gonna have iCloud update, + +444 +00:23:09,255 --> 00:23:14,024 +okay, this thing up here that updates, try to do this again. + +445 +00:23:14,026 --> 00:23:17,928 +Okay? Now let's go and put this t retry in there and + +446 +00:23:17,930 --> 00:23:20,765 +we'll see what some of these errors that are. + +447 +00:23:20,767 --> 00:23:25,102 +So this is a private func retryAfterError, + +448 +00:23:25,104 --> 00:23:27,671 +takes an error, do an NSError. + +449 +00:23:27,673 --> 00:23:31,409 +And then it takes with selector. We'll have a nice + +450 +00:23:31,411 --> 00:23:35,379 +local name for that and this is a selector, okay. + +451 +00:23:35,381 --> 00:23:38,716 +So we have errors here, so what is this error. It says, + +452 +00:23:38,718 --> 00:23:38,816 +selector refers to + +453 +00:23:38,818 --> 00:23:42,219 +a method that does not expose to objective C. That's iCloud. + +454 +00:23:42,221 --> 00:23:45,723 +Now why is this iCloud update not exposed to objective C? + +455 +00:23:45,725 --> 00:23:47,758 +Well, it's because it's private, okay. + +456 +00:23:47,760 --> 00:23:50,394 +This is a class that inherits from in it' s objects, so + +457 +00:23:50,396 --> 00:23:52,763 +that's not the problem. The problem is that we have + +458 +00:23:52,765 --> 00:23:54,565 +a private method here. So we can expose it + +459 +00:23:54,567 --> 00:23:57,668 +either by making it not private or just saying OBJC. + +460 +00:23:57,670 --> 00:24:01,672 +That mean, hey, expose this to Objective-C run time. Okay? + +461 +00:24:01,674 --> 00:24:06,610 +Make sense? All right, here is now saying the call + +462 +00:24:06,612 --> 00:24:12,016 +to the method iCloud update requires explicit self, okay? + +463 +00:24:12,018 --> 00:24:15,019 +So that it knows, in our self because we happen to be + +464 +00:24:15,021 --> 00:24:17,888 +in a closure right here, okay? All references to + +465 +00:24:17,890 --> 00:24:21,792 +things in our selves Have to be explicit. Okay, so + +466 +00:24:21,794 --> 00:24:24,862 +that's good. All right, now, retry after or how we gonna + +467 +00:24:24,864 --> 00:24:29,233 +retry after. Well, if we can't get that retry interval magic + +468 +00:24:29,235 --> 00:24:32,269 +out of the error structure then we cannot do it so + +469 +00:24:32,271 --> 00:24:33,103 +that's the first thing we're gonna do. + +470 +00:24:33,105 --> 00:24:36,607 +We're gonna say if we can let retry interval + +471 +00:24:37,276 --> 00:24:41,011 +equal the errors. User info, okay so + +472 +00:24:41,013 --> 00:24:44,582 +user info is this dictionary that comes with an error that + +473 +00:24:44,584 --> 00:24:46,317 +gives you kind of interesting info. + +474 +00:24:46,319 --> 00:24:51,989 +And, the thing we want is ck error, + +475 +00:24:51,991 --> 00:24:55,359 +retry after key, okay? So + +476 +00:24:55,361 --> 00:25:00,664 +that should be an ns time interval. So if we're able to + +477 +00:25:00,666 --> 00:25:05,135 +get that retry interval, then hey, let's go ahead and retry. + +478 +00:25:05,471 --> 00:25:09,340 +And how are we going to retry here? Well I'm just going to + +479 +00:25:09,342 --> 00:25:13,777 +do an NSTimer, scheduled timer with time interval, + +480 +00:25:13,779 --> 00:25:18,282 +I want this one, let's go ahead and make this + +481 +00:25:19,819 --> 00:25:24,054 +have different lines here so you can see little better what + +482 +00:25:24,056 --> 00:25:28,359 +we're doing with the timer. Okay, so the time interval + +483 +00:25:28,361 --> 00:25:31,829 +here is that retry interval that we got out of the error. + +484 +00:25:31,831 --> 00:25:34,532 +The target is going to be our self. + +485 +00:25:34,534 --> 00:25:39,270 +The selector is the selector we passed on Here, okay? + +486 +00:25:39,272 --> 00:25:42,606 +User info, eh, we don't have any, we're just retrying, so + +487 +00:25:42,608 --> 00:25:48,779 +we don't have any extra data, and it does not repeat. Okay, + +488 +00:25:48,781 --> 00:25:51,181 +now the problem here we gotta be careful of, + +489 +00:25:51,183 --> 00:25:54,051 +we're calling retry after error in this closure, + +490 +00:25:54,053 --> 00:25:57,922 +which is executing off the main thread. Okay, so + +491 +00:25:57,924 --> 00:26:00,958 +we cannot do NSTimers on other threads. So + +492 +00:26:00,960 --> 00:26:08,399 +we need to dispatc_async, to the main queue. + +493 +00:26:08,401 --> 00:26:13,103 +Dispatc_Ge_mai_queue. + +494 +00:26:13,105 --> 00:26:18,042 +We'll do this, like that. Okay, + +495 +00:26:18,044 --> 00:26:23,047 +you got that? Cool, all right so + +496 +00:26:23,049 --> 00:26:27,184 +that's just a couple of the errors that we can do. + +497 +00:26:27,186 --> 00:26:29,787 +If it succeeds, we actually don't need to do anything. + +498 +00:26:29,789 --> 00:26:30,554 +It saved it, we're happy, + +499 +00:26:30,556 --> 00:26:35,793 +we can just move on, okay. All right, so let's try and + +500 +00:26:35,795 --> 00:26:37,027 +run this, let's just see if it happens, + +501 +00:26:37,029 --> 00:26:40,030 +let's see if it can save this thing to the database. So + +502 +00:26:40,032 --> 00:26:46,971 +I'm gonna run, all right, here we crashed, + +503 +00:26:46,973 --> 00:26:50,874 +now why'd we crash? The first place I'm always gonna + +504 +00:26:50,876 --> 00:26:53,611 +look is the console down here. So let's go take a look at + +505 +00:26:53,613 --> 00:26:57,948 +the console and see if it has a reason that it crashed and + +506 +00:26:57,950 --> 00:26:59,249 +it does have a reason. And the reason is, + +507 +00:26:59,251 --> 00:27:02,853 +this application is missing the required entitlement for + +508 +00:27:02,855 --> 00:27:03,253 +iCloud services. + +509 +00:27:03,255 --> 00:27:05,356 +So this is that thing I was telling you about. + +510 +00:27:05,358 --> 00:27:06,523 +We have to go enable iCloud, + +511 +00:27:06,525 --> 00:27:09,627 +all right. Because iCloud is server technology. Gee, + +512 +00:27:09,629 --> 00:27:11,862 +things are gonna have to be created on a server side for + +513 +00:27:11,864 --> 00:27:14,732 +this app, etcetera. So they don't want to create that for + +514 +00:27:14,734 --> 00:27:16,967 +every app, only for apps that are actually gonna use it. + +515 +00:27:16,969 --> 00:27:20,804 +So how do we do that? We go up here, okay, to our inspector, + +516 +00:27:20,806 --> 00:27:23,040 +inspect our project settings here and + +517 +00:27:23,042 --> 00:27:24,642 +we'll go to capabilities. + +518 +00:27:24,644 --> 00:27:27,578 +And we click iCloud here, okay? So you have to make sure + +519 +00:27:27,580 --> 00:27:30,748 +you pick a team, okay, cuz it needs to know who you are so + +520 +00:27:30,750 --> 00:27:33,550 +we can set up this iCloud stuff for you, okay? + +521 +00:27:33,552 --> 00:27:37,855 +Your, account, your developer account up there. So + +522 +00:27:37,857 --> 00:27:40,824 +here we have iCloud enabled, we are going to pick cloud kit + +523 +00:27:40,826 --> 00:27:45,963 +as that's the service that we want, we can pick these other + +524 +00:27:45,965 --> 00:27:48,899 +ones as well but we're going to focus on CloudKit today. + +525 +00:27:48,901 --> 00:27:52,169 +And we'll be looking at the dashboard in a little bit, + +526 +00:27:52,171 --> 00:27:55,005 +actually let's go take a look at our dashboard now. + +527 +00:27:55,007 --> 00:27:58,409 +Once your at dashboard, of course you have to log in. + +528 +00:27:58,711 --> 00:28:00,611 +Here we are, nothing has been created yet and + +529 +00:28:00,613 --> 00:28:03,714 +that's because we haven't done any iCloud where we have + +530 +00:28:03,716 --> 00:28:08,652 +tried to create any entities, okay? All right, so + +531 +00:28:08,654 --> 00:28:10,587 +now that we've done that. Now let's go back and + +532 +00:28:10,589 --> 00:28:14,091 +run, and do that. And actually create some entities. So let's + +533 +00:28:14,093 --> 00:28:19,063 +get our code back up here so you can see that. And run. + +534 +00:28:23,769 --> 00:28:28,105 +All right. So here we go. Blank question and answer. + +535 +00:28:28,107 --> 00:28:35,813 +Let's go ahead a put a question answer here again, + +536 +00:28:35,815 --> 00:28:40,884 +let's try how about what is your + +537 +00:28:40,886 --> 00:28:46,056 +favorite team? Okay, + +538 +00:28:46,058 --> 00:28:52,396 +we'll say, maybe the Sharks. Whoops. Sharks, + +539 +00:28:52,398 --> 00:28:59,903 +or maybe the Warriors, or maybe it's the Giants. Okay, + +540 +00:29:00,106 --> 00:29:02,473 +there are a lot of teams to choose from in the Bay area. + +541 +00:29:02,475 --> 00:29:07,377 +All right? So hopefully this is creating on the server + +542 +00:29:07,379 --> 00:29:12,116 +because remember every time we went to a new field, + +543 +00:29:12,118 --> 00:29:13,884 +it should be riding something up to the Cloud. + +544 +00:29:13,886 --> 00:29:18,722 +So let's go back and take a look at our dashboard here, so + +545 +00:29:18,724 --> 00:29:23,460 +let's reload, Here it is, look at that, + +546 +00:29:23,462 --> 00:29:26,363 +QandA entity got created with answers and questions. + +547 +00:29:26,365 --> 00:29:28,732 +So that's great. So that's the entity side of it. + +548 +00:29:28,734 --> 00:29:30,400 +And we can actually look at the data, + +549 +00:29:30,402 --> 00:29:33,270 +not just the entity, but the data that's been stored by + +550 +00:29:33,272 --> 00:29:34,872 +going down here to this Default Zone. + +551 +00:29:34,874 --> 00:29:36,840 +Now, we'll notice when we try to look in here for + +552 +00:29:36,842 --> 00:29:39,409 +things, it says, records can't be shown because there's no + +553 +00:29:39,411 --> 00:29:42,446 +index on the Record ID field. So you can't look at things + +554 +00:29:42,448 --> 00:29:46,517 +that aren't indexed. And so let me show you where that is. + +555 +00:29:46,519 --> 00:29:49,486 +If you go back here you see metadata indexes, + +556 +00:29:49,488 --> 00:29:52,856 +record ID not being indexed. Same thing created by. + +557 +00:29:52,858 --> 00:29:55,225 +In fact I want both of those to be searchable. + +558 +00:29:55,227 --> 00:29:58,862 +I need created by so I know which Q&As were created by me, + +559 +00:29:58,864 --> 00:30:00,297 +and I want record ID so + +560 +00:30:00,299 --> 00:30:02,166 +I can go find all the ones out there. And + +561 +00:30:02,168 --> 00:30:04,635 +you can actually see here I'm gonna go ahead and save this. + +562 +00:30:04,637 --> 00:30:06,703 +I'll show you something real quick here. So + +563 +00:30:06,705 --> 00:30:08,772 +I've changed this to have these indexes. + +564 +00:30:08,774 --> 00:30:11,275 +Now I can go to the default zone. It can find things and + +565 +00:30:11,277 --> 00:30:13,610 +sure enough. What is your favorite team? Sharks and + +566 +00:30:13,612 --> 00:30:19,016 +Warriors. I guess we didn't save the Giants one here. When + +567 +00:30:19,018 --> 00:30:21,919 +we reload, we'll see that. One thing about the car I + +568 +00:30:21,921 --> 00:30:26,690 +wanted to show you the costs thing, which is down here. + +569 +00:30:26,692 --> 00:30:31,028 +If you look at uhs where is that uhs + +570 +00:30:31,931 --> 00:30:34,865 +usage? If you look at usage right here it is going to show + +571 +00:30:34,867 --> 00:30:37,668 +you how much you using how many active users you have, + +572 +00:30:37,670 --> 00:30:40,070 +how many request per second, how much transfers you + +573 +00:30:40,072 --> 00:30:42,906 +are doing of large files. How much storage you're using. All + +574 +00:30:42,908 --> 00:30:46,210 +that stuff. And these things if you go above these lines, + +575 +00:30:46,212 --> 00:30:48,478 +start costing you money. See these red lines. + +576 +00:30:48,480 --> 00:30:52,416 +Okay, the limits? Usage? So, I'm way, way below everything. + +577 +00:30:52,418 --> 00:30:53,917 +[LAUGH] Obviously. But, you know. + +578 +00:30:53,919 --> 00:30:58,622 +So, this is basically how you get charged for it, okay? + +579 +00:30:58,624 --> 00:31:03,193 +That good? All right. So we've got our nice database is being + +580 +00:31:03,195 --> 00:31:06,129 +loaded up, it's excellent, okay? The next thing we're + +581 +00:31:06,131 --> 00:31:11,168 +gonna do in our UI here is we are going to have another + +582 +00:31:11,170 --> 00:31:15,038 +view controller that has a list of all the question, + +583 +00:31:15,040 --> 00:31:16,773 +the Q&A's that are in the database, okay? + +584 +00:31:16,775 --> 00:31:20,277 +That we can choose from, and take a look at the Q&A's Okay, + +585 +00:31:20,279 --> 00:31:23,513 +so it's just gonna be a simple table view with a list of + +586 +00:31:23,515 --> 00:31:26,316 +the QNAs. All right, so how we gonna do that, + +587 +00:31:26,318 --> 00:31:29,820 +we gonna have to create a new MVC. So lets go ahead and + +588 +00:31:29,822 --> 00:31:34,091 +do that, go file, new, go touch, this one is just going + +589 +00:31:34,093 --> 00:31:36,860 +to be a regular UI table view controller, + +590 +00:31:36,862 --> 00:31:41,031 +am gonna call it my AllQandAsTableViewController, + +591 +00:31:41,033 --> 00:31:42,866 +cuz that's what it's gonna do. + +592 +00:31:42,868 --> 00:31:45,402 +It's gonna be the table view controller, shows all my Q and + +593 +00:31:45,404 --> 00:31:49,139 +As in it, okay? And we'll put it in the same place + +594 +00:31:49,141 --> 00:31:53,777 +as usual here. Here's all Q and As. Let's go ahead and + +595 +00:31:53,779 --> 00:32:02,953 +get rid of all of this stuff. Okay, + +596 +00:32:02,955 --> 00:32:06,990 +so as always, what's gonna be the model of our new MVC? + +597 +00:32:06,992 --> 00:32:10,661 +Well, it shows all Q and A's, so that's gonna be my model, + +598 +00:32:10,663 --> 00:32:13,897 +all the Q and A's. And that's just going to be an array of + +599 +00:32:13,899 --> 00:32:19,436 +CKRecord, okay. And of course, when that changes, + +600 +00:32:19,438 --> 00:32:22,339 +if someone changes that array of records, then I'm going to + +601 +00:32:22,341 --> 00:32:26,376 +have the table view reload its data. Hopefully you're all + +602 +00:32:26,378 --> 00:32:30,047 +familiar with that after Smashtag experiences. Okay, so + +603 +00:32:30,049 --> 00:32:35,285 +it's as simple as that. So how do we get all these Q and A's? + +604 +00:32:35,287 --> 00:32:39,489 +Import CloudKit. How do we get them all? Well, + +605 +00:32:39,491 --> 00:32:43,327 +in my view, let's do it in viewWillAppear, okay, + +606 +00:32:43,329 --> 00:32:48,498 +when I know I'm gonna come on screen. I'm + +607 +00:32:48,500 --> 00:32:52,035 +going to call some method to fetchAllQandAs, okay, and + +608 +00:32:52,037 --> 00:32:56,440 +that's gonna go out to CloudKit and find them all. So + +609 +00:32:56,442 --> 00:33:01,478 +that's private method called fetchAllQAndAs. + +610 +00:33:01,480 --> 00:33:06,883 +Oops. Okay, and how's this thing gonna work? Well, + +611 +00:33:06,885 --> 00:33:09,853 +this is gonna turn out to be very, very simple. Of course, + +612 +00:33:09,855 --> 00:33:12,022 +we need our database here, so let's get that. + +613 +00:33:12,024 --> 00:33:15,258 +CKContainer.defaultContainer, again, we're looking in + +614 +00:33:15,260 --> 00:33:18,662 +the public database there. All right, we have a database. So + +615 +00:33:18,664 --> 00:33:22,332 +fetching all the QandAs really just requires doing a CKQuery. + +616 +00:33:22,334 --> 00:33:24,468 +You remember that from the slide CKQuery? + +617 +00:33:24,470 --> 00:33:27,871 +So for CKQuery, we need a predicate, okay? + +618 +00:33:27,873 --> 00:33:30,974 +And since I'm getting all of the QandA's, + +619 +00:33:30,976 --> 00:33:34,845 +every single one, I'm not searching for anything, + +620 +00:33:34,847 --> 00:33:38,982 +I'm gonna use the predicate TRUEPREDICATE. Okay, this + +621 +00:33:38,984 --> 00:33:42,753 +is a special predicate that means, get them all. Okay, + +622 +00:33:42,755 --> 00:33:45,856 +remember, in Core Data, we have nil means get them all, + +623 +00:33:45,858 --> 00:33:48,191 +but here, you can't have predicate be nil, so + +624 +00:33:48,193 --> 00:33:52,529 +TRUEPREDICATE. It means get them all. Okay? Next, + +625 +00:33:52,531 --> 00:33:58,268 +we can just create the query itself. That's a CKQuery, + +626 +00:33:58,270 --> 00:34:03,673 +okay? And we'll get its initializer here. So it + +627 +00:34:03,675 --> 00:34:05,876 +just wants to know what kind of things are you querying. + +628 +00:34:05,878 --> 00:34:08,211 +It's just like when you're doing NSFetchRequest in + +629 +00:34:08,213 --> 00:34:10,847 +Core Data. You can only query one kind of thing at a time, + +630 +00:34:10,849 --> 00:34:15,819 +one entity at a time. So here we're gonna have Cloud.Entity, + +631 +00:34:15,821 --> 00:34:20,390 +Entity.QandA, cuz that's what we're searching for, + +632 +00:34:20,392 --> 00:34:22,759 +these QandA entities, entities. + +633 +00:34:22,761 --> 00:34:25,162 +And here's the predicate we're gonna use. Now, + +634 +00:34:25,164 --> 00:34:28,065 +one thing I forgot to show you in the slides, very important, + +635 +00:34:28,067 --> 00:34:30,934 +is sorting. Just like in NSFetchRequest, you can + +636 +00:34:30,936 --> 00:34:35,272 +do this here as well. I can say query.sortDescriptors, and + +637 +00:34:35,274 --> 00:34:37,340 +I can specify how I want to sort + +638 +00:34:37,342 --> 00:34:40,677 +this query that I'm doing. Okay? So I'll have a sort, + +639 +00:34:40,679 --> 00:34:42,813 +we'll sort this by the name of the, + +640 +00:34:42,815 --> 00:34:44,614 +by the question name, okay. So + +641 +00:34:44,616 --> 00:34:49,719 +key is Cloud.Attribute.Question, and + +642 +00:34:49,721 --> 00:34:54,524 +we'll have it be ascending. Okay, and of course, + +643 +00:34:54,526 --> 00:34:57,260 +this is an array just like it is with fetch request, + +644 +00:34:57,262 --> 00:34:59,963 +you can search last name first, then by first name, + +645 +00:34:59,965 --> 00:35:04,067 +et cetera. Okay, so that's it. We've created our carry, + +646 +00:35:04,069 --> 00:35:07,137 +query, how we wanna sort it, what the predicate is. + +647 +00:35:07,139 --> 00:35:11,775 +Now we just ask the database to perform this query. + +648 +00:35:11,777 --> 00:35:16,012 +Okay? And the query is query. Now, this inZoneWithID, + +649 +00:35:16,014 --> 00:35:18,849 +I told you that there's these zones, that are like subareas + +650 +00:35:18,851 --> 00:35:21,618 +of databases. By dividing your database into zone, + +651 +00:35:21,620 --> 00:35:23,386 +you can make your queries a lot more efficient. + +652 +00:35:23,388 --> 00:35:26,223 +You can see why already, if I only am searching a small part + +653 +00:35:26,225 --> 00:35:29,159 +of my database, it makes it a lot faster to search. + +654 +00:35:29,161 --> 00:35:32,329 +Here we're not using zones, okay, so we're just + +655 +00:35:32,331 --> 00:35:35,565 +putting nil as our zone. But if you have a huge data set, + +656 +00:35:35,567 --> 00:35:39,569 +you can look into the zones feature. Okay, so here's my + +657 +00:35:39,571 --> 00:35:42,772 +closure, when the results come back sometime later. + +658 +00:35:42,774 --> 00:35:46,743 +This is the array of records that it found with that query. + +659 +00:35:46,745 --> 00:35:50,680 +And here's the error if any that it found. Okay? Now, + +660 +00:35:50,682 --> 00:35:54,951 +what am I gonna do with these records that came back? Well, + +661 +00:35:54,953 --> 00:35:58,822 +if the records is not nil, in other words, + +662 +00:35:58,824 --> 00:36:03,426 +if it found any records, then I just need to set my + +663 +00:36:03,428 --> 00:36:07,631 +allQandAs equal to those records. All right? + +664 +00:36:07,633 --> 00:36:12,602 +But be careful. This is not happening on the main queue. + +665 +00:36:12,604 --> 00:36:16,206 +So, if we're gonna do this, which is gonna cause this, + +666 +00:36:16,208 --> 00:36:20,877 +reloadData to happen, means we have to dispatc_async onto + +667 +00:36:20,879 --> 00:36:25,782 +the main queue. Okay? + +668 +00:36:25,784 --> 00:36:27,584 +So don't forget that dispatching back to the main + +669 +00:36:27,586 --> 00:36:32,889 +queue when you're gonna do UI stuff as a response. Okay? So + +670 +00:36:32,891 --> 00:36:34,591 +that's it. Okay, super easy. + +671 +00:36:34,593 --> 00:36:38,528 +The only thing we have left to do in this TableViewController + +672 +00:36:38,530 --> 00:36:40,697 +is our UITableViewDataSource. So + +673 +00:36:40,699 --> 00:36:45,769 +let's mark UITableViewDataSource. + +674 +00:36:45,771 --> 00:36:48,205 +Okay, we don't have any sections in this table, okay, + +675 +00:36:48,207 --> 00:36:52,943 +it's just all just one big section. The number of rows, + +676 +00:36:52,945 --> 00:36:56,413 +okay, let's do the number of rows. + +677 +00:36:56,415 --> 00:37:00,116 +That's just the number of things in our array, + +678 +00:37:00,118 --> 00:37:04,688 +AllQandAs.count. That's how many rows we have, obviously. + +679 +00:37:04,690 --> 00:37:07,157 +And then we also obviously need cellForRowAtIndexPath. + +680 +00:37:07,159 --> 00:37:11,561 +cellForRowAtIndexPath. So cellForRowAtIndexPath, which + +681 +00:37:11,563 --> 00:37:14,831 +we have, well, here, let's make it a little wider here. + +682 +00:37:14,833 --> 00:37:15,799 +Okay, cellForRowAtIndexPath. + +683 +00:37:15,801 --> 00:37:22,038 +I'm gonna get the cell by using the tableViews.dequeue, + +684 +00:37:22,040 --> 00:37:26,276 +whoops, view's dequeue with identifier. + +685 +00:37:26,278 --> 00:37:30,180 +So what identifier should we use? Let's say a QandA Cell. + +686 +00:37:30,182 --> 00:37:35,318 +So let's go back to our storyboard. And + +687 +00:37:35,320 --> 00:37:39,789 +have the cells of this. First of all, let's put our table + +688 +00:37:39,791 --> 00:37:42,892 +view in here. How about that? So here's a table view. + +689 +00:37:42,894 --> 00:37:45,595 +This is gonna be in between these two. All right. + +690 +00:37:45,597 --> 00:37:48,131 +This one is going to be the root view controller, and we + +691 +00:37:48,133 --> 00:37:51,101 +are going to be segueing from this one to this one which + +692 +00:37:51,103 --> 00:37:54,170 +shows them. Let's make sure we set our identity of this to be + +693 +00:37:54,172 --> 00:37:58,642 +our new allQandAs table here. Here's our cells right here. + +694 +00:37:58,644 --> 00:38:01,378 +So these cells, we're gonna have them be basic style, + +695 +00:38:01,380 --> 00:38:03,013 +cuz they just have the question. + +696 +00:38:03,015 --> 00:38:04,114 +We're just gonna put the question, so + +697 +00:38:04,116 --> 00:38:04,714 +they don't have any subtitle. + +698 +00:38:04,716 --> 00:38:07,083 +They don't need any custom stuff. And + +699 +00:38:07,085 --> 00:38:12,122 +the identifier is the QandA Cell. Okay, + +700 +00:38:12,124 --> 00:38:15,058 +hey, while were here, let's go ahead do the segues for this. + +701 +00:38:15,060 --> 00:38:17,861 +It's really simple. We're gonna segue from these rows. + +702 +00:38:17,863 --> 00:38:19,863 +Okay, anytime someone clicks on these rows, + +703 +00:38:19,865 --> 00:38:22,098 +we're gonna segue over to here and do a show segue. + +704 +00:38:22,100 --> 00:38:25,969 +And we also want to be able to create new questions as well, + +705 +00:38:25,971 --> 00:38:28,271 +right? We're gonna click on questions we got, + +706 +00:38:28,273 --> 00:38:29,205 +but we want to create new ones. + +707 +00:38:29,207 --> 00:38:31,741 +So I'm gonna do that with some UI in here. + +708 +00:38:31,743 --> 00:38:36,446 +I'm gonna create a Bar Button Item right here. And + +709 +00:38:36,448 --> 00:38:38,982 +I'll use the standard plus one, which is add, okay, + +710 +00:38:38,984 --> 00:38:41,017 +cuz we're gonna add something, this is plus. + +711 +00:38:41,019 --> 00:38:43,219 +And then we're just gonna Ctrl+drag from here and + +712 +00:38:43,221 --> 00:38:47,223 +make that show. Okay, so this is gonna do a segue, if fact, + +713 +00:38:47,225 --> 00:38:48,124 +they can do the same segue, + +714 +00:38:48,126 --> 00:38:50,126 +cuz they pretty much do the same thing. + +715 +00:38:50,128 --> 00:38:51,227 +They show a Q and A, it's just, + +716 +00:38:51,229 --> 00:38:53,863 +one of them shows whatever row is selected and + +717 +00:38:53,865 --> 00:38:55,432 +the other one creates a new one. So + +718 +00:38:55,434 --> 00:38:58,468 +we'll call this Show QandA. That's a good name for + +719 +00:38:58,470 --> 00:39:03,506 +that. And we'll call this one also Show QandA. Now, + +720 +00:39:03,508 --> 00:39:05,475 +in our prepare for segue, we're gonna have to be, + +721 +00:39:05,477 --> 00:39:08,044 +do a little bit different thing, in those two cases, + +722 +00:39:08,046 --> 00:39:11,481 +but that's basically what we're doing. Okay? So + +723 +00:39:11,483 --> 00:39:16,586 +let's go back to our code here. allQandAs. + +724 +00:39:16,588 --> 00:39:21,391 +So here's our cell index path there. Let's + +725 +00:39:21,393 --> 00:39:26,629 +just have our cell's textLabel?.text equal what? + +726 +00:39:26,631 --> 00:39:30,233 +allQandAs sub indexPath.row. + +727 +00:39:30,235 --> 00:39:34,371 +That's giving me the CKRecord. Now, out of that CKRecord, + +728 +00:39:34,373 --> 00:39:37,974 +I've gotta get the Cloud.Attribute.Question, + +729 +00:39:37,976 --> 00:39:40,543 +cuz that's what I'm gonna show, + +730 +00:39:40,545 --> 00:39:41,811 +inside that row. And of course, + +731 +00:39:41,813 --> 00:39:44,080 +we know that comes back as a CKRecord value, so + +732 +00:39:44,082 --> 00:39:50,153 +I have to say, as a String. Okay? And then we will + +733 +00:39:50,155 --> 00:39:55,392 +return the cell. Okay? Also super simple. + +734 +00:39:55,394 --> 00:39:57,660 +All right, make sense? And now let's prepare for segue. + +735 +00:39:57,662 --> 00:40:02,332 +So that's mark our Navigation. Prepare for + +736 +00:40:02,334 --> 00:40:06,403 +segue. This is also gonna be pretty straightforward. First, + +737 +00:40:06,405 --> 00:40:11,141 +we're gonna see if the identifier is our + +738 +00:40:11,143 --> 00:40:15,845 +Show QandA. If it is, let's get that MVC. + +739 +00:40:15,847 --> 00:40:20,049 +So we'll say, if we can let the cloud Q and, QandA, + +740 +00:40:20,051 --> 00:40:24,788 +oops, CloudKit Q and A table view controller equal our + +741 +00:40:24,790 --> 00:40:28,224 +segue's destinationViewController as + +742 +00:40:28,226 --> 00:40:31,060 +a CloudQandATableViewController, + +743 +00:40:31,062 --> 00:40:34,898 +okay, so we're segueing into one of those, so + +744 +00:40:34,900 --> 00:40:39,235 +that better be on the other end. If that's true, + +745 +00:40:39,237 --> 00:40:41,971 +then we need the cell, if we're segueing from a row, + +746 +00:40:41,973 --> 00:40:45,475 +we need the cell, so let's try that. So if we can let cell + +747 +00:40:45,477 --> 00:40:49,846 +equal the sender as a UITableViewCell, okay, + +748 +00:40:49,848 --> 00:40:52,549 +hopefully you guys are used to doing this, again, from your + +749 +00:40:52,551 --> 00:40:56,553 +homework assignment. And then we can let the indexPath equal + +750 +00:40:56,555 --> 00:41:01,324 +the tableView's method cell for, or sorry, index path, + +751 +00:41:01,326 --> 00:41:05,995 +PathForCell, this cell. + +752 +00:41:05,997 --> 00:41:09,232 +Okay, so here is kind of a one-liner that gets the index + +753 +00:41:09,234 --> 00:41:14,237 +path of the row that was chosen. And if that works, + +754 +00:41:14,239 --> 00:41:19,342 +then we can just say that the CloudQandA, oops, + +755 +00:41:19,344 --> 00:41:22,178 +I guess I called it ckQandATVC, + +756 +00:41:22,180 --> 00:41:27,550 +we'll set its public API, which is ckQandARecord, + +757 +00:41:27,552 --> 00:41:32,288 +okay, equal to allQandAs sub indexPath.row. + +758 +00:41:32,290 --> 00:41:36,259 +All right? That's what's, that's the record that + +759 +00:41:36,261 --> 00:41:38,962 +was chosen there, obviously. If we can't get the cell, + +760 +00:41:38,964 --> 00:41:42,031 +if we can't get the table view cell, that must be because we + +761 +00:41:42,033 --> 00:41:45,201 +pressed the + button, right? Because the plus button's not + +762 +00:41:45,203 --> 00:41:47,170 +a row in a table. So in that case, + +763 +00:41:47,172 --> 00:41:51,608 +I'm just going to set the ckQandARecord equal to a new + +764 +00:41:51,610 --> 00:41:56,646 +record, because that's what we want. Creating a new + +765 +00:41:56,648 --> 00:42:01,718 +thing here, so that's Cloud.Entity.QandA. + +766 +00:42:01,720 --> 00:42:05,989 +Okay, everyone understand that prepareForSegue? + +767 +00:42:05,991 --> 00:42:07,724 +Okay, so let's do that. + +768 +00:42:17,035 --> 00:42:18,701 +All right, so here's it showing all the ones, and + +769 +00:42:18,703 --> 00:42:20,937 +look, it's even showing, what is your favorite team, + +770 +00:42:20,939 --> 00:42:22,005 +that we already had from before. + +771 +00:42:22,007 --> 00:42:26,109 +I'm gonna touch on that, and it's not showing it to us. + +772 +00:42:26,111 --> 00:42:31,247 +Okay. Why is it not showing it to us? When we click on this, + +773 +00:42:31,249 --> 00:42:33,483 +it shows a blank one. Why does it show a blank one? + +774 +00:42:33,485 --> 00:42:37,153 +Because over here, in our CloudTableViewController, + +775 +00:42:37,155 --> 00:42:40,223 +look what we do in our viewDidLoad. + +776 +00:42:40,225 --> 00:42:42,458 +No! We always set the record to be nil. + +777 +00:42:42,460 --> 00:42:47,397 +So, let's get rid of that. And allow the segue to actually + +778 +00:42:47,399 --> 00:42:51,901 +set it. That's a tricky little bug. + +779 +00:43:00,812 --> 00:43:02,378 +Okay, so now, when we click on this, + +780 +00:43:02,380 --> 00:43:08,084 +we get to see the question out of the database. Okay? And + +781 +00:43:08,086 --> 00:43:14,691 +we can hit + and create a new one, + +782 +00:43:14,693 --> 00:43:19,462 +maybe like, what is your + +783 +00:43:19,464 --> 00:43:24,367 +favorite Stanford class? + +784 +00:43:24,369 --> 00:43:29,572 +Okay, and we'll have some answers here, + +785 +00:43:29,574 --> 00:43:34,110 +how about CS193p, or if not that, + +786 +00:43:34,112 --> 00:43:40,283 +how about iOS development. Okay, + +787 +00:43:40,285 --> 00:43:47,223 +that's a great class too. And how about the iPhone and + +788 +00:43:47,225 --> 00:43:52,228 +iPad programming course. + +789 +00:43:52,230 --> 00:43:54,063 +You can pick whatever Stanford class you'd like. + +790 +00:43:54,065 --> 00:43:59,302 +Okay? So that, when we go back now, it's gonna ask for all of + +791 +00:43:59,304 --> 00:44:02,805 +those Q&As and it's gonna show that one as well. Okay? So + +792 +00:44:02,807 --> 00:44:05,842 +that you can see, very little code we had to write here to + +793 +00:44:05,844 --> 00:44:09,779 +have it so that we're creating these things and editing them. + +794 +00:44:09,781 --> 00:44:14,317 +What about deleting them? Okay? What if I said, eh, + +795 +00:44:14,319 --> 00:44:15,752 +I don't want this one anymore, I wanna delete it. + +796 +00:44:15,754 --> 00:44:18,788 +What would be really cool is if I could just swipe on this + +797 +00:44:18,790 --> 00:44:20,490 +to delete. You've seen that in table views, right? + +798 +00:44:20,492 --> 00:44:23,459 +Where you can swipe to delete, okay? How do we do swipe, + +799 +00:44:23,461 --> 00:44:26,095 +swipe to delete? We have never covered that in class. + +800 +00:44:26,097 --> 00:44:27,463 +This is a great opportunity to do that. + +801 +00:44:27,465 --> 00:44:28,798 +So if you want to do swipe to delete, + +802 +00:44:28,800 --> 00:44:32,135 +you have to implement two of your UITableViewDataSource + +803 +00:44:32,137 --> 00:44:35,371 +methods. One is, you have to answer whether a row + +804 +00:44:35,373 --> 00:44:37,807 +can be deleted or not. Okay? That one is called + +805 +00:44:37,809 --> 00:44:42,912 +canEditRowAtIndexPath. Okay, canEditRowAtIndexPath. + +806 +00:44:42,914 --> 00:44:46,649 +Now, in our case, as long as we created this, then we can + +807 +00:44:46,651 --> 00:44:49,152 +allow it to delete it, but if we didn't create it, we can't. + +808 +00:44:49,154 --> 00:44:55,058 +So here I'm gonna return all Q&As at the indexPath.row was + +809 +00:44:55,060 --> 00:44:58,828 +created by this user. So if it was created by this user, + +810 +00:44:58,830 --> 00:45:02,632 +then I'll allow you to delete it. Okay? The other method you + +811 +00:45:02,634 --> 00:45:05,001 +need is the thing that actually commits the delete, + +812 +00:45:05,003 --> 00:45:09,338 +that does the delete. That's called commitEditingStyle. + +813 +00:45:09,340 --> 00:45:11,407 +Okay, commitEditingStyle right here, + +814 +00:45:11,409 --> 00:45:14,477 +TableView.commitEditingStyle. And so here, + +815 +00:45:14,479 --> 00:45:17,246 +there's actually two editing styles that you can have. + +816 +00:45:17,248 --> 00:45:18,715 +One is deleting and one is inserting. + +817 +00:45:18,717 --> 00:45:21,417 +Well, we do our inserting with that plus, so we don't need + +818 +00:45:21,419 --> 00:45:25,021 +the inserting style there. We only want the deleting, so + +819 +00:45:25,023 --> 00:45:27,957 +I'm gonna say, if the editingStyle == .Delete. + +820 +00:45:27,959 --> 00:45:32,895 +Okay, so if the person wants to delete my row or whatever, + +821 +00:45:32,897 --> 00:45:36,532 +then all I need to do is delete it from the table. But + +822 +00:45:36,534 --> 00:45:40,436 +I also wanna delete it from the database as well, right, + +823 +00:45:40,438 --> 00:45:44,107 +both of those. So what's that look like? So let's say, + +824 +00:45:44,109 --> 00:45:47,376 +if we're deleting, then I'm gonna let the record to delete + +825 +00:45:47,378 --> 00:45:51,948 +equal, my allQandAs indexPath.row. + +826 +00:45:51,950 --> 00:45:56,686 +Okay. Then I'm gonna save the database. Please delete this + +827 +00:45:56,688 --> 00:46:02,191 +record with an ID, and the ID is the record's recordID, + +828 +00:46:02,193 --> 00:46:05,428 +okay. Completion handler here to handle errors. + +829 +00:46:05,430 --> 00:46:09,999 +This is the deleted record, if it happened, + +830 +00:46:10,001 --> 00:46:14,070 +or error if it didn't. And so, handle errors. I'm, again, + +831 +00:46:14,072 --> 00:46:18,908 +short on time. So we're not going to do that. And + +832 +00:46:18,910 --> 00:46:21,744 +in either case, even if it didn't, you know, + +833 +00:46:21,746 --> 00:46:25,081 +even if it failed to delete, I'm still gonna go ahead and + +834 +00:46:25,083 --> 00:46:29,952 +delete it out of allQandAs. So to do that, I just say + +835 +00:46:29,954 --> 00:46:36,225 +allQandAs.removeAtIndex the indexPath.row. + +836 +00:46:36,227 --> 00:46:38,728 +Okay, so it's just gonna delete it from the thing. Now, + +837 +00:46:38,730 --> 00:46:42,131 +hopefully, this was successful and it won't come back later, + +838 +00:46:42,133 --> 00:46:45,802 +but it's gonna delete here. So let's take a look at this. + +839 +00:46:53,645 --> 00:46:55,845 +All right, so we created both of these, so + +840 +00:46:55,847 --> 00:46:58,881 +I can swipe to delete, right, either one I wanted. + +841 +00:46:58,883 --> 00:47:01,284 +So let's delete, let's delete this one. + +842 +00:47:01,286 --> 00:47:04,687 +It's gone. Okay, and we can make sure it actually deleted + +843 +00:47:04,689 --> 00:47:06,322 +it in the database by going away and coming back, + +844 +00:47:06,324 --> 00:47:09,225 +cuz it reloads when it does that. It didn't come back, so + +845 +00:47:09,227 --> 00:47:10,693 +it actually deleted that from the database. + +846 +00:47:10,695 --> 00:47:13,663 +We could also go over and look in our database right here, + +847 +00:47:13,665 --> 00:47:15,598 +in our default zone. And we can see, we only have, + +848 +00:47:15,600 --> 00:47:19,836 +what is your favorite team. We could reload just to be 100% + +849 +00:47:19,838 --> 00:47:22,238 +sure. Default zone. Sure enough, we only have, + +850 +00:47:22,240 --> 00:47:26,008 +what is your favorite team? It deleted it. Okay? All right, + +851 +00:47:26,010 --> 00:47:29,178 +so that's great. All right. One bad thing about our UI, + +852 +00:47:29,180 --> 00:47:32,415 +though is, you see this nice little table view? If I'm just + +853 +00:47:32,417 --> 00:47:36,085 +sitting here and someone else creates something, it doesn't + +854 +00:47:36,087 --> 00:47:40,790 +show me. So let's go over here on iPhone simulator here, + +855 +00:47:40,792 --> 00:47:42,992 +and I'm gonna create a new one. + +856 +00:47:42,994 --> 00:47:48,197 +I'm gonna see what happens. Okay, so it's showing, + +857 +00:47:48,199 --> 00:47:51,634 +what is your favorite team? So I'll create a new one here, + +858 +00:47:51,636 --> 00:47:54,270 +I'll say, what is your favorite color? + +859 +00:47:54,272 --> 00:48:00,142 +That's our kind of our favorite one. Red and Blue. + +860 +00:48:00,144 --> 00:48:04,213 +And black, okay? Now, I've created this but it's not + +861 +00:48:04,215 --> 00:48:07,049 +showing up over here, right? And it's not showing up there + +862 +00:48:07,051 --> 00:48:10,286 +because I'm not subscribing to that change. I'm not watching + +863 +00:48:10,288 --> 00:48:14,523 +the database. Now, if I go away from this and come back, + +864 +00:48:14,525 --> 00:48:16,726 +it is gonna show it. Because when we viewWillAppear, + +865 +00:48:16,728 --> 00:48:19,495 +we reload from the database. But it's really annoying for + +866 +00:48:19,497 --> 00:48:21,364 +the user to always to have to go away and + +867 +00:48:21,366 --> 00:48:23,566 +come back to the see the latest, thing. So, + +868 +00:48:23,568 --> 00:48:27,136 +we need to do a subscription, okay? Perfect opportunity to + +869 +00:48:27,138 --> 00:48:29,705 +do a subscription. So let's do that. + +870 +00:48:29,707 --> 00:48:34,243 +So, how do we do the subscription? Pretty simple, + +871 +00:48:34,245 --> 00:48:36,746 +it's two parts really, three parts to doing it. + +872 +00:48:36,748 --> 00:48:39,181 +The first one is we need to actually subscribe. + +873 +00:48:39,183 --> 00:48:40,549 +So let's do the subscription first. + +874 +00:48:40,551 --> 00:48:45,922 +I'll even put this in a little MARK: Subscription place here. + +875 +00:48:45,924 --> 00:48:50,159 +One thing is we need to have an ID for our subscription. + +876 +00:48:50,161 --> 00:48:51,193 +So, I'm gonna say subscriptionID. + +877 +00:48:51,195 --> 00:48:54,430 +And this is just an English language description of what + +878 +00:48:54,432 --> 00:48:57,400 +we're gonna subscribe to. And so I'm gonna say, + +879 +00:48:57,402 --> 00:49:00,603 +we're gonna get All QandA Creations and Deletions. + +880 +00:49:00,605 --> 00:49:04,407 +And this has gotta uniquely identify this subscription in + +881 +00:49:04,409 --> 00:49:04,540 +the database and + +882 +00:49:04,542 --> 00:49:07,777 +I think that pretty uniquely identifies what we're doing + +883 +00:49:07,779 --> 00:49:12,515 +here. So, let me create a private func here + +884 +00:49:12,517 --> 00:49:16,652 +called iCloudSubscribeToQandAs, okay? + +885 +00:49:16,654 --> 00:49:19,622 +And this thing is going to do the subscription. So + +886 +00:49:19,624 --> 00:49:22,858 +when you do a subscription you need a predicate that says, + +887 +00:49:22,860 --> 00:49:23,993 +what you're looking for, okay? + +888 +00:49:23,995 --> 00:49:27,430 +What you're trying to find out when it changes. So again, + +889 +00:49:27,432 --> 00:49:31,233 +we're gonna use pretty much the same one we used before + +890 +00:49:31,235 --> 00:49:34,337 +which is true predicate, TRUEPREDICATE, yeah. + +891 +00:49:34,339 --> 00:49:37,239 +Because, we are looking for any additions or + +892 +00:49:37,241 --> 00:49:40,543 +deletions of Q and A, not, not just the ones we created, or + +893 +00:49:40,545 --> 00:49:42,645 +not just ones with certain questions but + +894 +00:49:42,647 --> 00:49:42,812 +any of them, so + +895 +00:49:42,814 --> 00:49:45,314 +that's why we're using the same predicate. And then, + +896 +00:49:45,316 --> 00:49:50,286 +we just create the subscription. Okay, + +897 +00:49:50,288 --> 00:49:57,126 +CKSubscription. And, it's, this one right here. + +898 +00:49:57,128 --> 00:49:59,528 +And let's go ahead and put this on separate lines, + +899 +00:49:59,530 --> 00:50:03,833 +as I am wont to do when there are lots of arguments so + +900 +00:50:03,835 --> 00:50:07,136 +you can see what's going on, okay? So the recordType is, + +901 +00:50:07,138 --> 00:50:09,872 +what kind of thing we're watching, and of course here, + +902 +00:50:09,874 --> 00:50:13,075 +we are watching Entity.QandA. That's what we're looking for + +903 +00:50:13,077 --> 00:50:18,447 +searches for. predicate: is our predicate, okay. + +904 +00:50:18,449 --> 00:50:20,483 +subscriptionID: is our subscriptionID. + +905 +00:50:20,485 --> 00:50:23,452 +I'm putting self in there just to emphasize that + +906 +00:50:23,454 --> 00:50:24,353 +it's my subscription ID, + +907 +00:50:24,355 --> 00:50:26,789 +okay? And then, the subscription options: are what + +908 +00:50:26,791 --> 00:50:29,658 +kind of changes are we looking for? So we want ones that + +909 +00:50:29,660 --> 00:50:34,263 +fire when one's created, and we also want to find out when + +910 +00:50:34,265 --> 00:50:37,867 +one's deleted. Cuz we're showing a list of the suf, + +911 +00:50:37,869 --> 00:50:40,403 +of the Q and As, so we don't care if one gets + +912 +00:50:40,405 --> 00:50:43,339 +updated. Although, we might care if it's updated because + +913 +00:50:43,341 --> 00:50:44,573 +maybe it changed the question and + +914 +00:50:44,575 --> 00:50:45,474 +now the list should change there. + +915 +00:50:45,476 --> 00:50:48,544 +But I'm just gonna do creation and deletion here, to show you + +916 +00:50:48,546 --> 00:50:51,981 +that. Now, one thing here that I'm not gonna do, but + +917 +00:50:51,983 --> 00:50:56,552 +that you can do here, is there is a notification info + +918 +00:50:56,554 --> 00:51:00,089 +argument, or, var on subscription that you can use + +919 +00:51:00,091 --> 00:51:04,460 +to say, what happens when the push notification comes, when + +920 +00:51:04,462 --> 00:51:06,662 +this changes. Does it put up an alert? Does it put a badge? + +921 +00:51:06,664 --> 00:51:10,533 +Does it increase the badge, right? On your app icon, okay? + +922 +00:51:10,535 --> 00:51:13,169 +Does it play a sound? Bloop, things arrived. Okay, you can + +923 +00:51:13,171 --> 00:51:16,138 +set that here. I'm gonna have none of those things happening + +924 +00:51:16,140 --> 00:51:18,674 +I'm just going to behind the scenes fix up the table. + +925 +00:51:18,676 --> 00:51:20,309 +I'm not gonna put any alerts up or whatever. + +926 +00:51:20,311 --> 00:51:23,746 +But I just wanna let you know, you can do that here, okay? + +927 +00:51:23,748 --> 00:51:27,349 +So, we got that, so let's just go to our database and + +928 +00:51:27,351 --> 00:51:29,652 +tell it to save this subscription, okay. + +929 +00:51:29,654 --> 00:51:33,322 +Save our subscription with our completion handler right here, + +930 +00:51:33,324 --> 00:51:36,292 +okay. Here is the savedSubscription, + +931 +00:51:36,294 --> 00:51:39,695 +if it succeeded, and here's an error if not. + +932 +00:51:39,697 --> 00:51:42,698 +I'm gonna take a second to show you an error here because + +933 +00:51:42,700 --> 00:51:48,137 +there's a common one that happens. error?.code == + +934 +00:51:48,139 --> 00:51:55,010 +CKErrorCode.ServerRejectedReq- uest, + +935 +00:51:55,012 --> 00:51:58,581 +okay? And what happens here sometimes is, + +936 +00:51:58,583 --> 00:52:01,417 +if this subscription by its unique name is already on + +937 +00:52:01,419 --> 00:52:05,054 +the server, then it will reject your request, okay? + +938 +00:52:05,056 --> 00:52:08,157 +So, this usually means that you ran your program, + +939 +00:52:08,159 --> 00:52:10,626 +you were developing, you, this code ran, + +940 +00:52:10,628 --> 00:52:13,162 +and then you hit stop in the debugger, okay? + +941 +00:52:13,164 --> 00:52:15,664 +It killed your app. And then you ran it again, and + +942 +00:52:15,666 --> 00:52:18,434 +it tried to do it, it's still there. Okay, the subscriptions + +943 +00:52:18,436 --> 00:52:21,637 +live forever, until you actually remove them, okay? + +944 +00:52:21,639 --> 00:52:24,773 +So quitting your app has no effect on the subscriptions. + +945 +00:52:24,775 --> 00:52:27,843 +So, this is one where usually you'll ignore that + +946 +00:52:27,845 --> 00:52:29,979 +ServerRejectedRequest figuring eh, somehow, + +947 +00:52:29,981 --> 00:52:33,549 +this thing got got already put in there. That's fine, + +948 +00:52:33,551 --> 00:52:36,218 +we'll just use it, okay, it'll continue to work just fine. + +949 +00:52:36,220 --> 00:52:39,522 +Okay and else, you know, if there's some error, + +950 +00:52:39,524 --> 00:52:40,823 +other kind of error, you know, + +951 +00:52:40,825 --> 00:52:44,226 +report that error or whatever you feel like you need to do. + +952 +00:52:44,228 --> 00:52:48,597 +Okay, so that's it, that's all that's necessary to get iCloud + +953 +00:52:48,599 --> 00:52:53,102 +to start, you know, sending us push notifications when, + +954 +00:52:53,104 --> 00:52:56,839 +any of these creations and deletions happen to any Q and + +955 +00:52:56,841 --> 00:52:59,208 +A. Now, one thing is we're subscribing here. + +956 +00:52:59,210 --> 00:53:02,578 +We also are probably want to unsubscribed and + +957 +00:53:02,580 --> 00:53:04,547 +when would we want to do those two things. + +958 +00:53:04,549 --> 00:53:08,918 +So I'm gonna have an unsubscribe as well, + +959 +00:53:08,920 --> 00:53:12,087 +Unsubscribe. And when do we wanna do this? + +960 +00:53:12,089 --> 00:53:14,790 +Probably, we'll want to, when viewWillAppear, + +961 +00:53:14,792 --> 00:53:16,825 +we wanna subscribe and when viewDisappears, + +962 +00:53:16,827 --> 00:53:19,762 +we unsubscribe. Okay, because it's no use sending these push + +963 +00:53:19,764 --> 00:53:21,163 +notifications if we're not even on screen. + +964 +00:53:21,165 --> 00:53:24,233 +Okay, especially since when we reappear we reload ourselves + +965 +00:53:24,235 --> 00:53:28,070 +anyway. Okay, so there's no reason to do that. So, + +966 +00:53:28,072 --> 00:53:31,473 +in viewWillAppear right here, + +967 +00:53:31,475 --> 00:53:36,645 +I'm gonna say, iCloudSubscribeToQandAs, + +968 +00:53:36,647 --> 00:53:41,784 +and in viewDidDisappear, I'm gonna say, + +969 +00:53:41,786 --> 00:53:45,821 +iCloudUnsubscribe, okay? Now, + +970 +00:53:45,823 --> 00:53:48,991 +iCloudUnsubscribe, what do we need to do to unsubscribe? + +971 +00:53:48,993 --> 00:53:53,295 +Very easy, I'm just gonna say to my database, please + +972 +00:53:53,297 --> 00:53:57,199 +deleteSubscriptionWithID, my subscriptionID, + +973 +00:53:57,201 --> 00:54:01,537 +okay? Completion handler to handle errors here. So + +974 +00:54:01,539 --> 00:54:05,407 +this is, the subscription that we tried to delete. + +975 +00:54:05,409 --> 00:54:08,344 +There's an error. We will not handle errors cuz we're + +976 +00:54:08,346 --> 00:54:11,947 +running out of time. Handle it, okay? So, we'll just + +977 +00:54:11,949 --> 00:54:16,518 +delete those, descriptions there and that's it. Okay, so + +978 +00:54:16,520 --> 00:54:20,489 +now we've set up our table here to get those updates but + +979 +00:54:20,491 --> 00:54:23,158 +of course, we have to be able to receive push notifications + +980 +00:54:23,160 --> 00:54:26,762 +for this to work, okay? And we do that, over in our app + +981 +00:54:26,764 --> 00:54:29,898 +delegate. So lets go back to our app delegate right here, + +982 +00:54:29,900 --> 00:54:32,067 +and look at that code that we covered in lecture. + +983 +00:54:32,069 --> 00:54:34,436 +One, in did finish launching with options, + +984 +00:54:34,438 --> 00:54:36,171 +we need to register for + +985 +00:54:36,173 --> 00:54:38,307 +the kinds of notifications + +986 +00:54:38,309 --> 00:54:40,242 +we're willing to present to our user, okay? + +987 +00:54:40,244 --> 00:54:43,112 +And the user actually can choose in settings, + +988 +00:54:43,114 --> 00:54:46,248 +the general settings, whether they want alerts or badges or + +989 +00:54:46,250 --> 00:54:48,917 +sounds or whatever, but we're going to explain here + +990 +00:54:48,919 --> 00:54:52,454 +which ones we think we want to give them, okay? So, + +991 +00:54:52,456 --> 00:54:56,859 +we do that by just creating the settings, by that's + +992 +00:54:56,861 --> 00:55:01,430 +a UIUserNotificationSettings, and for + +993 +00:55:01,432 --> 00:55:04,733 +the types that we want. And this can be like alerts, + +994 +00:55:04,735 --> 00:55:09,405 +badges, sounds, okay? And I'll go ahead and register for + +995 +00:55:09,407 --> 00:55:11,874 +all of them, although, I'm not gonna use any of them cuz I, + +996 +00:55:11,876 --> 00:55:14,043 +that subscription.notification info, remember that? + +997 +00:55:14,045 --> 00:55:16,912 +I didn't put that line in, so it's not gonna do any of these + +998 +00:55:16,914 --> 00:55:20,215 +things. But, I, I'm gonna tell the user, hey, I wanna do all + +999 +00:55:20,217 --> 00:55:22,818 +these things cuz maybe some of my other push notifications + +1000 +00:55:22,820 --> 00:55:25,854 +wanted to do it or whatever. But I wouldn't sign up for + +1001 +00:55:25,856 --> 00:55:28,490 +these actually if you're not gonna use them cuz it just + +1002 +00:55:28,492 --> 00:55:32,861 +creates unnecessary stuff for your user, all right? + +1003 +00:55:32,863 --> 00:55:35,297 +So there's the settings, so now I have to register + +1004 +00:55:35,299 --> 00:55:39,068 +those settings, so I just say application.registerUserNotif- + +1005 +00:55:39,070 --> 00:55:40,669 +icationSettings, those settings. + +1006 +00:55:40,671 --> 00:55:44,807 +And now, I need to turn on push notifications, okay? + +1007 +00:55:44,809 --> 00:55:47,810 +registerForRemoteNotificati- ons, okay? + +1008 +00:55:47,812 --> 00:55:51,013 +Push notifications are called remote notifications, okay? + +1009 +00:55:51,015 --> 00:55:53,449 +Boom, so now I've turned on push notifications, + +1010 +00:55:53,451 --> 00:55:54,850 +they're gonna start coming, okay? + +1011 +00:55:54,852 --> 00:55:58,187 +From Cloudkit, or whatever else ones that I set up. + +1012 +00:55:58,189 --> 00:56:02,191 +So now I have to handle them when they arrive, and I do + +1013 +00:56:02,193 --> 00:56:06,595 +that with this thing called the remote notification, + +1014 +00:56:06,597 --> 00:56:09,498 +didReceiveRemoteNotification, okay? + +1015 +00:56:09,500 --> 00:56:12,301 +A remote notification came in, what am I gonna do with it? + +1016 +00:56:12,303 --> 00:56:15,671 +Well, I'm gonna assume that it's a CloudKit one here. + +1017 +00:56:15,673 --> 00:56:17,740 +I don't have any other ones that I'm expecting, so + +1018 +00:56:17,742 --> 00:56:19,641 +that should be fine. If I had other ones, + +1019 +00:56:19,643 --> 00:56:23,011 +I'd have to do more code here. But I'm just gonna say, + +1020 +00:56:23,013 --> 00:56:27,383 +if I can, or actually, I mean, yeah, if I'm gonna let CQ, + +1021 +00:56:27,385 --> 00:56:31,453 +ckqn, that's short for CloudKit query notification, + +1022 +00:56:31,455 --> 00:56:35,357 +equals CKQueryNotification, CKQueryNotification, + +1023 +00:56:35,359 --> 00:56:40,996 +okay, that's not completing because, import CloudKit. + +1024 +00:56:41,866 --> 00:56:43,699 +Okay, so I'm gonna create a query notification. + +1025 +00:56:43,701 --> 00:56:47,169 +The only way to create one of these things is to hand + +1026 +00:56:47,171 --> 00:56:51,707 +the dictionary that comes with the push notification off to + +1027 +00:56:51,709 --> 00:56:55,444 +this constructor, okay, this initializer. + +1028 +00:56:55,446 --> 00:56:56,178 +So I'm gonna give it that. + +1029 +00:56:56,180 --> 00:56:58,914 +One thing that's unfortunate about that is that it wants + +1030 +00:56:58,916 --> 00:57:03,952 +that to be a dictionary where Strings are the keys and + +1031 +00:57:03,954 --> 00:57:05,387 +NSObjects are the values, + +1032 +00:57:05,389 --> 00:57:09,258 +instead of NSObjects as the keys, AnyObject as the value. + +1033 +00:57:09,260 --> 00:57:12,995 +Okay? So, you just have to do this. All right, so + +1034 +00:57:12,997 --> 00:57:17,132 +I've got my query notification that came from CloudKit. + +1035 +00:57:17,134 --> 00:57:20,369 +Awesome. Now I need to hand it out to all my view controllers + +1036 +00:57:20,371 --> 00:57:22,104 +that might be interested. And as we said in lecture, + +1037 +00:57:22,106 --> 00:57:24,273 +we're gonna do this with a radio station. Okay, so + +1038 +00:57:24,275 --> 00:57:30,612 +let's create a radio station. notification = NSNotification, + +1039 +00:57:30,614 --> 00:57:35,984 +all right, we're gonna use this one right here. Again, + +1040 +00:57:35,986 --> 00:57:41,323 +I will help you out a little bit. See what's going on. + +1041 +00:57:42,159 --> 00:57:44,993 +All right, so name is the name of the radio station, and + +1042 +00:57:44,995 --> 00:57:47,062 +as I told you, in that CloudKit extensions, + +1043 +00:57:47,064 --> 00:57:50,365 +I created something for that. So I called that + +1044 +00:57:50,367 --> 00:57:54,803 +CloudKitNotifications.notific- ation, + +1045 +00:57:54,805 --> 00:57:58,440 +what did I call it? So I have to go back and look here. + +1046 +00:57:58,442 --> 00:58:02,444 +Supporting Files, extension, CloudKitNotification. + +1047 +00:58:02,446 --> 00:58:05,848 +NotificationReceived. That's the name of my radio station, + +1048 +00:58:05,850 --> 00:58:09,017 +NotificationReceived. Sorry. + +1049 +00:58:13,724 --> 00:58:17,926 +NotificationReceived. Okay, so that's the name. AnyObject, + +1050 +00:58:17,928 --> 00:58:19,928 +this object is the sender. Ha, that's self, + +1051 +00:58:19,930 --> 00:58:22,064 +that's my AppDelegate. Doesn't really matter too much, + +1052 +00:58:22,066 --> 00:58:24,299 +cuz I'm not gonna look at it in the other end. And + +1053 +00:58:24,301 --> 00:58:28,337 +then the userInfo, I need to pass this ckqn on. + +1054 +00:58:28,339 --> 00:58:30,839 +So I'm gonna create a little dictionary on the fly here. + +1055 +00:58:30,841 --> 00:58:35,143 +And the key is gonna be my CloudKitNotifications.Notific- + +1056 +00:58:35,145 --> 00:58:41,216 +ationKey. And the value is gonna be that ckqn. Okay? + +1057 +00:58:41,218 --> 00:58:44,753 +So this is the thing I'm gonna pass out onto, this is + +1058 +00:58:44,755 --> 00:58:48,957 +Received, this is the thing I'm gonna pass out on my radio + +1059 +00:58:48,959 --> 00:58:53,462 +station. So let's go ahead and broadcast it by saying + +1060 +00:58:53,464 --> 00:58:59,935 +NSNotificationCenter.defaultC- enter, post this notification, + +1061 +00:58:59,937 --> 00:59:03,705 +that means broadcast on this radio station. + +1062 +00:59:03,707 --> 00:59:06,875 +Okay, now everybody who is signed up to listen is going + +1063 +00:59:06,877 --> 00:59:11,013 +to get this push notification forwarded onto them. Okay? + +1064 +00:59:11,015 --> 00:59:15,484 +So now let's go back and sign up over here to get that. + +1065 +00:59:15,486 --> 00:59:16,718 +And I'm gonna do it in my subscribe, + +1066 +00:59:16,720 --> 00:59:19,054 +when I subscribe to the Q and A's, I'm gonna then go and + +1067 +00:59:19,056 --> 00:59:22,925 +sign up for that radio station so I can hear the results. And + +1068 +00:59:22,927 --> 00:59:26,061 +to do that, I need that little, cookie. So + +1069 +00:59:26,063 --> 00:59:31,066 +private var, we'll call it cloudKitObserver. It's gonna + +1070 +00:59:31,068 --> 00:59:34,369 +be an NSObjectProtocol optional right there. + +1071 +00:59:34,371 --> 00:59:38,040 +Okay, I'm gonna say cloudKitObserver = and + +1072 +00:59:38,042 --> 00:59:42,311 +I'm just gonna ask the notification center if I can + +1073 +00:59:42,313 --> 00:59:46,181 +please listen to that radio station by saying, + +1074 +00:59:46,183 --> 00:59:52,921 +addObserverForName. It's this one. Okay, again. + +1075 +00:59:55,826 --> 00:59:58,427 +I'd love if there was a nice little single key to do that + +1076 +00:59:58,429 --> 01:00:01,330 +for me. So here's the radio station that I wanna listen + +1077 +01:00:01,332 --> 01:00:04,900 +to, which is CloudKitNotifications.Notific- + +1078 +01:00:04,902 --> 01:00:08,203 +ationReceived, that's the name of the radio station. + +1079 +01:00:08,205 --> 01:00:10,939 +AnyObject, I don't care. And if anybody sends me that, I'm + +1080 +01:00:10,941 --> 01:00:12,975 +gonna listen, okay? I could put the AppDelegate here, but + +1081 +01:00:12,977 --> 01:00:15,677 +I'm just gonna say anybody. And I'm gonna do some UI here, + +1082 +01:00:15,679 --> 01:00:19,715 +so I'd better say [INAUDIBLE] NSOperationQueue.mainQueue, + +1083 +01:00:19,717 --> 01:00:21,850 +okay, send me this on the main queue. And + +1084 +01:00:21,852 --> 01:00:24,186 +then here's the block, okay? This argument is + +1085 +01:00:24,188 --> 01:00:28,490 +the notification that's coming along in the radio station. + +1086 +01:00:28,492 --> 01:00:33,662 +And I need to get the ck, ckqn out of the user info + +1087 +01:00:33,664 --> 01:00:37,466 +in that notification. Okay, so what does that look like? + +1088 +01:00:37,468 --> 01:00:40,168 +Actually, I'm gonna do all that in a different method. + +1089 +01:00:40,170 --> 01:00:44,673 +I'm gonna have iCloudHandleSubscriptionNotif- + +1090 +01:00:44,675 --> 01:00:50,212 +ication, and I'm just gonna pass ckqn on to that. + +1091 +01:00:50,214 --> 01:00:52,648 +So the cq, ckqn here, we can say, + +1092 +01:00:52,650 --> 01:00:57,085 +if we can let ckqn equal the notification's userInfo, + +1093 +01:00:57,087 --> 01:01:01,456 +which might be nil, you have to be careful about that, + +1094 +01:01:01,458 --> 01:01:06,194 +and I'm gonna get the CloudKit notification key here, + +1095 +01:01:06,196 --> 01:01:09,698 +notification's NotificationKey, okay. + +1096 +01:01:09,700 --> 01:01:13,702 +And that better be a CKQuery notification, or + +1097 +01:01:13,704 --> 01:01:15,904 +I don't know what to do with it, + +1098 +01:01:15,906 --> 01:01:19,708 +okay? So if I can get that out of the little radio station + +1099 +01:01:19,710 --> 01:01:23,712 +broadcast, then I'm gonna handle it. Okay, so + +1100 +01:01:23,714 --> 01:01:30,285 +how do I handle it? private func this thing, + +1101 +01:01:30,287 --> 01:01:34,723 +okay. And, there, we have a syntax + +1102 +01:01:34,725 --> 01:01:39,528 +error right here, this should be NotificationKey, + +1103 +01:01:39,530 --> 01:01:42,864 +NotificationKey. So handling it is pretty simple, + +1104 +01:01:42,866 --> 01:01:47,636 +actually. First, when handling it, I'm gonna make sure that + +1105 +01:01:47,638 --> 01:01:52,441 +this is for me. I'm gonna look at the subscription, + +1106 +01:01:52,443 --> 01:01:55,644 +sorry, ckqn is a CKQueryNotification. + +1107 +01:01:55,646 --> 01:01:58,480 +Okay, I'm gonna make sure that this thing is for me, + +1108 +01:01:58,482 --> 01:02:02,184 +to make sure its subscription ID equals my subscription ID. + +1109 +01:02:02,186 --> 01:02:04,386 +Because, remember, you might have lots of different view + +1110 +01:02:04,388 --> 01:02:07,122 +controllers getting push notifications from CloudKit, + +1111 +01:02:07,124 --> 01:02:09,758 +okay, doing different things. So here I want to make sure + +1112 +01:02:09,760 --> 01:02:14,329 +it's this one that I'm getting the answer back from. + +1113 +01:02:14,331 --> 01:02:16,832 +All right, so now that I have that, I'm just gonna get + +1114 +01:02:16,834 --> 01:02:19,835 +the record that changed, okay, the recordID that changed + +1115 +01:02:19,837 --> 01:02:24,473 +is ckqn.recordID, okay, so hopefully some record changed, + +1116 +01:02:24,475 --> 01:02:27,976 +deleted or created here, otherwise I wouldn't be here. + +1117 +01:02:27,978 --> 01:02:32,013 +I can also find out what changed. So I can say, + +1118 +01:02:32,015 --> 01:02:36,084 +what is the reason that I got this notification? And + +1119 +01:02:36,086 --> 01:02:38,120 +one reason could be because a record + +1120 +01:02:38,122 --> 01:02:42,657 +was created. Another reason might be cuz a record was + +1121 +01:02:42,659 --> 01:02:46,361 +deleted, okay? Otherwise, I don't care, + +1122 +01:02:46,363 --> 01:02:48,196 +cuz I only handle creations and deletions, + +1123 +01:02:48,198 --> 01:02:53,502 +all right? Let's do deletion first. It's a pretty easy one. + +1124 +01:02:53,504 --> 01:02:56,705 +Okay, so what happens, if something was deleted? Well, + +1125 +01:02:56,707 --> 01:03:00,208 +I'm just gonna dispatc_async back the the main queue and + +1126 +01:03:00,210 --> 01:03:02,344 +remove it from my all QAs thing. So + +1127 +01:03:02,346 --> 01:03:08,350 +dispatc_ge_mai_queue. And I'm just gonna say, + +1128 +01:03:08,352 --> 01:03:14,055 +self.allQandAs equals self.allQandAs, + +1129 +01:03:14,057 --> 01:03:18,927 +and I'm just gonna filter out any records + +1130 +01:03:18,929 --> 01:03:23,598 +where the $0.recordID does not equal + +1131 +01:03:23,600 --> 01:03:27,669 +this recordID that was just deleted. + +1132 +01:03:27,671 --> 01:03:30,739 +Okay, so filter goes through all the things in the array, + +1133 +01:03:30,741 --> 01:03:31,673 +$0 is each thing in the array, + +1134 +01:03:31,675 --> 01:03:34,543 +I'm gonna get the recordID of the thing that's in there. + +1135 +01:03:34,545 --> 01:03:35,844 +And if it's not equal to the recordID, + +1136 +01:03:35,846 --> 01:03:38,480 +then I'm gonna filter it, if it is equal to the record ID, + +1137 +01:03:38,482 --> 01:03:41,516 +then it's not gonna get through the filter. + +1138 +01:03:41,718 --> 01:03:44,920 +Everybody got that? Super simple. Created, + +1139 +01:03:44,922 --> 01:03:47,155 +slightly more difficult, although only slightly. + +1140 +01:03:47,157 --> 01:03:50,625 +So, here, I'm gonna check if I have a record, + +1141 +01:03:50,627 --> 01:03:53,795 +if the record okay, let's, first of all, + +1142 +01:03:53,797 --> 01:03:57,699 +we have the record ID here. To show this record in our, + +1143 +01:03:57,701 --> 01:04:01,236 +in our table, we actually need the record, + +1144 +01:04:01,238 --> 01:04:01,670 +not the record ID. + +1145 +01:04:01,672 --> 01:04:05,373 +By the way, it is possible in our subscription to have said, + +1146 +01:04:05,375 --> 01:04:08,910 +hey when you give this thing, also give me the question. + +1147 +01:04:08,912 --> 01:04:11,213 +In other words, you can ask for certain fields so + +1148 +01:04:11,215 --> 01:04:13,448 +that I don't have to do what I'm doing right now, + +1149 +01:04:13,450 --> 01:04:16,384 +which is I'm going back to my database and + +1150 +01:04:16,386 --> 01:04:21,790 +fetching that record. Database. fetchRecordWithID. + +1151 +01:04:21,792 --> 01:04:24,626 +Which is kind of unfortunate that I have this record ID and + +1152 +01:04:24,628 --> 01:04:27,395 +I'm having to turn around and go back and fetch it. + +1153 +01:04:27,397 --> 01:04:29,497 +So, you don't have to do that if you, + +1154 +01:04:29,499 --> 01:04:30,665 +in your description say just give me + +1155 +01:04:30,667 --> 01:04:34,502 +that right off the bat, okay? You just specify which fields + +1156 +01:04:34,504 --> 01:04:37,272 +you want. Okay. So here's the record coming back, hopefully, + +1157 +01:04:37,274 --> 01:04:42,510 +not nil, and here's the error. Okay. So, if the record + +1158 +01:04:42,512 --> 01:04:46,815 +is not nil, I got it back. Now I need to add it to my Q and + +1159 +01:04:46,817 --> 01:04:49,784 +As, now, a slight complication here is when I put it in my + +1160 +01:04:49,786 --> 01:04:53,321 +list of Q and As, I obviously need to sort it. Because my + +1161 +01:04:53,323 --> 01:04:55,423 +list of Q and As was sorted by the database, but now I'm + +1162 +01:04:55,425 --> 01:04:58,593 +getting this one record that I have to put in the list. + +1163 +01:04:58,595 --> 01:04:59,060 +So, I have to do sorting. + +1164 +01:04:59,062 --> 01:05:00,362 +So, I'll show you a little bit how to do, ahh, + +1165 +01:05:00,364 --> 01:05:05,400 +sorting in here. Ahh, so, I'm gonna dispatc_async back to + +1166 +01:05:05,402 --> 01:05:10,639 +the main queue. Okay. + +1167 +01:05:10,641 --> 01:05:13,808 +And on here, I'm gonna say self.allQandAs, okay? + +1168 +01:05:13,810 --> 01:05:18,146 +Get ready for this, equals the self.allQandAs we got so far, + +1169 +01:05:18,148 --> 01:05:22,784 +plus this record. Okay. So now, this is the new thing + +1170 +01:05:22,786 --> 01:05:25,320 +with it appended on to the end, but the end is no good so + +1171 +01:05:25,322 --> 01:05:29,257 +I'm gonna sort. Okay? And when I sort, sort is + +1172 +01:05:29,259 --> 01:05:32,727 +gonna pass me dollar zero and dollar one. And I have to say, + +1173 +01:05:32,729 --> 01:05:35,297 +if dollar zero is less than or eq, or greater than dollar + +1174 +01:05:35,299 --> 01:05:38,667 +one. And that's how it's gonna sort everything. So, let's go + +1175 +01:05:38,669 --> 01:05:44,339 +ahead and return here. Dollar zero, which is a record, + +1176 +01:05:44,341 --> 01:05:48,043 +a ck record, so I'm gonna get the, Cloud.Attribute.Question, + +1177 +01:05:48,045 --> 01:05:52,113 +cuz I'm comparing the questions, quest- question, + +1178 +01:05:52,115 --> 01:05:55,750 +all right. But of course, I have to do it as a string, + +1179 +01:05:55,752 --> 01:05:59,387 +and I'm gonna see if that's less than $1, + +1180 +01:05:59,389 --> 01:06:07,228 +Cloud.Attribute.Question, also as a String. + +1181 +01:06:07,230 --> 01:06:10,832 +Okay. So, this is nice but + +1182 +01:06:10,834 --> 01:06:14,602 +this is really messy code, it looks absolutely awesome, + +1183 +01:06:14,604 --> 01:06:16,905 +awful here. Wouldn't it be cool if in, + +1184 +01:06:16,907 --> 01:06:17,872 +like we had in core data, + +1185 +01:06:17,874 --> 01:06:19,641 +where we could have the subclass and + +1186 +01:06:19,643 --> 01:06:22,344 +we just use vars for these things? Well, + +1187 +01:06:22,346 --> 01:06:25,413 +we can't quite do that, but watch this little trick. + +1188 +01:06:25,415 --> 01:06:27,682 +I'm going to go back to my supporting files, + +1189 +01:06:27,684 --> 01:06:30,618 +this CloudKit extensions thing that I did over here, okay? + +1190 +01:06:30,620 --> 01:06:36,124 +And I'm going to do this extension to CKRecord + +1191 +01:06:36,426 --> 01:06:43,431 +var question is a String, okay. I'm gonna return self + +1192 +01:06:43,433 --> 01:06:50,205 +sub Cloud.Attribute.Question as a String. And + +1193 +01:06:50,207 --> 01:06:53,708 +in fact, I want this to not be an optional. So I'm gonna say, + +1194 +01:06:53,710 --> 01:06:59,481 +??, empty. So, you see I've added a var question, + +1195 +01:06:59,483 --> 01:07:02,617 +to CkRecord that returns this thing. + +1196 +01:07:02,619 --> 01:07:07,188 +So now back in my other code over here, all this gunk just + +1197 +01:07:07,190 --> 01:07:11,860 +becomes .question. Okay, get rid of all this, + +1198 +01:07:11,862 --> 01:07:18,767 +.question. Okay, looks a lot nicer, doesn't it, okay? + +1199 +01:07:18,769 --> 01:07:21,236 +And in fact, we could use this .question in other places, + +1200 +01:07:21,238 --> 01:07:23,004 +like down here, in cell for row at indexPath, + +1201 +01:07:23,006 --> 01:07:27,342 +we do the same. A big mess right here, ,question. + +1202 +01:07:27,344 --> 01:07:30,311 +Okay. Now, okay, all your attributes would have to + +1203 +01:07:30,313 --> 01:07:32,947 +be unique across all of your entities or you would have to + +1204 +01:07:32,949 --> 01:07:35,750 +start putting the entity names somehow, in, in this name in + +1205 +01:07:35,752 --> 01:07:38,853 +this bar, but you know, something to consider, + +1206 +01:07:38,855 --> 01:07:40,755 +cleans up your code quite a bit. + +1207 +01:07:40,757 --> 01:07:44,526 +All right. Everyone, make sense what I did right there? + +1208 +01:07:44,528 --> 01:07:47,729 +By the way, if this record couldn't be fetched, + +1209 +01:07:47,731 --> 01:07:52,167 +then I'm kind of like, what the heck am I gonna do here? + +1210 +01:07:52,169 --> 01:07:53,701 +So, I might wanna do something here like, + +1211 +01:07:53,703 --> 01:07:57,005 +go reload my whole table, you know, do a fetch all q and + +1212 +01:07:57,007 --> 01:07:58,940 +a's, call fetch, dispatch, async, and all that, but + +1213 +01:07:58,942 --> 01:08:02,177 +I'm not gonna do it cuz we're out of time. Ahm, but, that's, + +1214 +01:08:02,179 --> 01:08:07,649 +I might want to react to this error somehow here. Okay? + +1215 +01:08:07,651 --> 01:08:09,851 +All right, so let's go back and + +1216 +01:08:09,853 --> 01:08:17,459 +let's run it on iPhone. And we'll run it on our device. + +1217 +01:08:26,570 --> 01:08:33,741 +All right. Okay. So let's go and create a new one here. + +1218 +01:08:33,743 --> 01:08:39,647 +Let's try, how do you greet people? + +1219 +01:08:40,050 --> 01:08:44,886 +And the answer is you say Hello, or maybe you say Aloha, + +1220 +01:08:44,888 --> 01:08:47,489 +and you can see as soon as I typed enough to get this thing + +1221 +01:08:47,491 --> 01:08:51,025 +to upload, it appeared here because it got noti, notified + +1222 +01:08:51,027 --> 01:08:54,629 +via the push notification. And in fact, I can look at it, + +1223 +01:08:54,631 --> 01:08:57,765 +let's see how do you greet people? Here we got hello, + +1224 +01:08:57,767 --> 01:09:00,568 +the Aloha has not even, been uploaded yet, so + +1225 +01:09:00,570 --> 01:09:05,240 +let's go ahead and hit the Aloha, then we get the Aloha. + +1226 +01:09:06,776 --> 01:09:09,110 +Okay? And same thing with delete, if we go back here and + +1227 +01:09:09,112 --> 01:09:10,845 +say, well we don't want this to greet people, + +1228 +01:09:10,847 --> 01:09:13,248 +hit delete. And it deleted on our iPhone, + +1229 +01:09:13,250 --> 01:09:16,818 +we don't have to wait back and forth. Okay, + +1230 +01:09:16,820 --> 01:09:21,156 +I will see you next time. >> For more, + +1231 +01:09:21,158 --> 01:09:21,189 +please visit us at stanford.edu. + diff --git a/subtitles/17. Segues, Core Location, and MapKit.srt b/subtitles/17. Segues, Core Location, and MapKit.srt new file mode 100644 index 0000000..0897112 --- /dev/null +++ b/subtitles/17. Segues, Core Location, and MapKit.srt @@ -0,0 +1,6108 @@ +1 +00:00:00,001 --> 00:00:03,802 +[MUSIC] + +2 +00:00:03,804 --> 00:00:08,440 +Stanford University. >> Okay, well, + +3 +00:00:08,442 --> 00:00:14,146 +welcome to Lecture 17 of Stanford CS193P + +4 +00:00:14,148 --> 00:00:19,518 +spring of 2016. This is our penultimate lecture that + +5 +00:00:19,520 --> 00:00:23,822 +actually has content. Next week we have Memorial Day, and + +6 +00:00:23,824 --> 00:00:27,760 +then we'll have our alternate final on Wednesday. + +7 +00:00:27,762 --> 00:00:28,861 +So what are we gonna talk about today? + +8 +00:00:28,863 --> 00:00:31,130 +Today we're gonna talk about segues, okay? + +9 +00:00:31,132 --> 00:00:32,398 +We've talked a lot about segues, but + +10 +00:00:32,400 --> 00:00:36,602 +there's still quite a few more segues to be talked about. And + +11 +00:00:36,604 --> 00:00:39,738 +then we're gonna talk about core location and MapKit, + +12 +00:00:39,740 --> 00:00:43,876 +which is kind of where is the device in the world. And then + +13 +00:00:43,878 --> 00:00:46,812 +I'm gonna do a demo, I'll do as much as the demo as I can, + +14 +00:00:46,814 --> 00:00:48,247 +and we'll just continue it on Wednesday. + +15 +00:00:48,249 --> 00:00:50,616 +The demo's gonna be about maps and segues, obviously, + +16 +00:00:50,618 --> 00:00:53,719 +that's what we're talking about today. All right? So + +17 +00:00:53,721 --> 00:00:55,220 +let's dive right in here to segues. + +18 +00:00:55,222 --> 00:00:59,792 +The first segue I'm gonna talk about is the modal segue. So, + +19 +00:00:59,794 --> 00:01:03,095 +this modal segue is the segue to an MVC that is gonna + +20 +00:01:03,097 --> 00:01:05,697 +completely take over your screen, okay? + +21 +00:01:05,699 --> 00:01:08,834 +You are fully responsible if you put a modal segue up for + +22 +00:01:08,836 --> 00:01:11,670 +providing a way for a user to get out of it, okay. + +23 +00:01:11,672 --> 00:01:15,307 +Because that MVC is completely in control. + +24 +00:01:15,309 --> 00:01:18,977 +This kind of UI should be used with care, okay, because you + +25 +00:01:18,979 --> 00:01:22,214 +really are locking down the UI, there's nothing else + +26 +00:01:22,216 --> 00:01:24,817 +the user can do. They can't. If they change their mind, + +27 +00:01:24,819 --> 00:01:27,653 +they can't go to another tab cuz it's not a tab bar thing. + +28 +00:01:27,655 --> 00:01:30,022 +They can't just hit back in a navigation controller, + +29 +00:01:30,024 --> 00:01:32,224 +they can't go to the other side of their split view or + +30 +00:01:32,226 --> 00:01:35,494 +whatever. They're pretty much stuck here until you let them, + +31 +00:01:35,496 --> 00:01:39,598 +out of it. And so, I don't even show you this until late + +32 +00:01:39,600 --> 00:01:40,466 +in the quarter because + +33 +00:01:40,468 --> 00:01:43,802 +I really don't want you to think of this as a go to way + +34 +00:01:43,804 --> 00:01:47,406 +to present an MVC on screen, okay? But it does have its + +35 +00:01:47,408 --> 00:01:50,242 +uses, okay? Here's an example, perhaps. Okay, + +36 +00:01:50,244 --> 00:01:54,746 +this is a contacts app, or an app that has contacts in it. + +37 +00:01:54,748 --> 00:01:56,281 +And we're showing the contacts and + +38 +00:01:56,283 --> 00:01:59,585 +the little plus button in the corner here, let's say that, + +39 +00:01:59,587 --> 00:02:02,521 +that button's going to allow us to enter a new contact. + +40 +00:02:02,523 --> 00:02:05,691 +Now, you could argue if the user has chosen to enter a new + +41 +00:02:05,693 --> 00:02:09,428 +contact. They don't wanna do anything else except for + +42 +00:02:09,430 --> 00:02:10,028 +that right now, and so + +43 +00:02:10,030 --> 00:02:13,298 +it's okay to present this adding contact view controller + +44 +00:02:13,300 --> 00:02:17,436 +modally. Modally just means in a mode where you can't + +45 +00:02:17,438 --> 00:02:19,605 +do anything else but this. Yeah, + +46 +00:02:19,607 --> 00:02:21,573 +one could argue there might be other ways to do this, + +47 +00:02:21,575 --> 00:02:24,209 +but let's, let's say that we're gonna do it this way. + +48 +00:02:24,211 --> 00:02:27,913 +So we tap on this plus sign, and from the bottom slides up + +49 +00:02:27,915 --> 00:02:30,916 +this new MVC. Now, this new MVC is completely controlling + +50 +00:02:30,918 --> 00:02:34,253 +the screen. It doesn't have a back button that cancel button + +51 +00:02:34,255 --> 00:02:37,256 +that you see right there. Is a button that this MVC is + +52 +00:02:37,258 --> 00:02:40,893 +putting in that bar, okay, it happens to cancel and + +53 +00:02:40,895 --> 00:02:42,995 +not add a new contact in this case. + +54 +00:02:42,997 --> 00:02:45,564 +Cuz it's not a push segue, it's a modal segue, + +55 +00:02:45,566 --> 00:02:48,901 +different kind of segue. And the thing about modal, as you + +56 +00:02:48,903 --> 00:02:52,137 +can actually have embedded modal inside modal, okay? So, + +57 +00:02:52,139 --> 00:02:55,541 +for example here, I am adding my contact, let's say now, + +58 +00:02:55,543 --> 00:02:58,010 +I wanna choose the photo for my contact, okay? + +59 +00:02:58,012 --> 00:03:01,280 +That's, also going to put up a modal MVC to get that. So + +60 +00:03:01,282 --> 00:03:05,117 +I click on that, another MVC slides off in the bottom so + +61 +00:03:05,119 --> 00:03:06,451 +now, I have two modal ones. + +62 +00:03:06,453 --> 00:03:08,554 +And you might think of this as a little bit like, + +63 +00:03:08,556 --> 00:03:08,787 +navigation control but + +64 +00:03:08,789 --> 00:03:10,756 +they're on a stack, but that's really not the way it is. + +65 +00:03:10,758 --> 00:03:14,393 +It's just the ad contact MVC took over the entire world and + +66 +00:03:14,395 --> 00:03:18,096 +then, it gave it to the photos one and it completely took + +67 +00:03:18,098 --> 00:03:20,599 +over the world. And until it's dismissed, + +68 +00:03:20,601 --> 00:03:22,234 +the other ones don't even really matter, + +69 +00:03:22,236 --> 00:03:26,872 +okay. Now, again notice no back button here. Also notice + +70 +00:03:26,874 --> 00:03:30,042 +by the way that cancel button has moved over from the right, + +71 +00:03:30,044 --> 00:03:32,110 +whereas on previous MVC had it on the left. + +72 +00:03:32,112 --> 00:03:35,113 +I'm not a big fun of this kind of UI, by the way. + +73 +00:03:35,115 --> 00:03:36,181 +I think, things like cancel, + +74 +00:03:36,183 --> 00:03:38,784 +if they're conceptually the same thing in two MVCs. + +75 +00:03:38,786 --> 00:03:41,753 +Especially, two MVCs that appear back to back like this, + +76 +00:03:41,755 --> 00:03:43,088 +should probably be in the same place. + +77 +00:03:43,090 --> 00:03:47,292 +So I would have put the cancel buttons both on the left here. + +78 +00:03:47,294 --> 00:03:51,430 +But whatever app this is or from where these contacts + +79 +00:03:51,432 --> 00:03:55,100 +came from, I decided to do that. But in any case, + +80 +00:03:55,102 --> 00:03:59,538 +no back button here. Right? Make sense? Okay, + +81 +00:03:59,540 --> 00:04:04,243 +so, let's cancel this and we'll see what happens to this + +82 +00:04:04,245 --> 00:04:07,112 +modal MVC. This cancel is a way to get out of it. + +83 +00:04:07,114 --> 00:04:07,579 +And when we cancel it, + +84 +00:04:07,581 --> 00:04:10,549 +of course, it slides back out. And the other MVC is still + +85 +00:04:10,551 --> 00:04:14,720 +there. Okay? Nothing has changed. And here, of course, + +86 +00:04:14,722 --> 00:04:17,789 +if we cancel this one, then we'll go back to where we were + +87 +00:04:17,791 --> 00:04:21,193 +before. And this MVC goes away. So that's modal, right? + +88 +00:04:21,195 --> 00:04:24,029 +You press the MVC. It lives, it does whatever it does. + +89 +00:04:24,031 --> 00:04:26,265 +It completely takes over the app and then somehow, + +90 +00:04:26,267 --> 00:04:29,167 +you press something to get out of it. Cancel or done, or + +91 +00:04:29,169 --> 00:04:33,605 +whatever, but that's totally up to that MVC. Right? So, + +92 +00:04:33,607 --> 00:04:37,109 +be careful is all I say about this. Don't go to modal first. + +93 +00:04:37,111 --> 00:04:39,845 +Think about whether there's a way to put it in a tab or + +94 +00:04:39,847 --> 00:04:43,348 +in your navigation stack, or something like that. Before + +95 +00:04:43,350 --> 00:04:46,752 +you jump right to choosing modal. All right, so how do we + +96 +00:04:46,754 --> 00:04:49,154 +set up a modal segue? How do we do one of these? + +97 +00:04:49,156 --> 00:04:51,957 +Just like all the other segues we've been doing, + +98 +00:04:51,959 --> 00:04:55,927 +you just CTRL+drag, from the thing that's going to cause + +99 +00:04:55,929 --> 00:04:59,331 +the modal segue to happen, to the MVC that's going to take + +100 +00:04:59,333 --> 00:05:02,601 +over the world. When you do that by the way, an important + +101 +00:05:02,603 --> 00:05:05,137 +thing to notice is that you can inspect the segue, and + +102 +00:05:05,139 --> 00:05:07,939 +a modal segue has different kinda things you can choose. + +103 +00:05:07,941 --> 00:05:10,709 +Which I'm gonna talk about, like how the modal segue is + +104 +00:05:10,711 --> 00:05:12,511 +presented. Does it slide up from the bottom or + +105 +00:05:12,513 --> 00:05:15,013 +do something else? And also, what does the modal segue + +106 +00:05:15,015 --> 00:05:18,216 +look like when it's there? Is it a take over the full screen + +107 +00:05:18,218 --> 00:05:20,319 +kind, okay, or is it some other kind. + +108 +00:05:20,321 --> 00:05:23,822 +We'll talk about what those other kinds can be. All right? + +109 +00:05:23,824 --> 00:05:28,727 +If you wanna present a modal MVC not from a button, okay or + +110 +00:05:28,729 --> 00:05:30,062 +from a bar button item. + +111 +00:05:30,064 --> 00:05:31,496 +You wanna do it from something else. Of course, + +112 +00:05:31,498 --> 00:05:33,865 +you can present it using the normal form segue with + +113 +00:05:33,867 --> 00:05:35,934 +identifier from your code. We've seen a couple of + +114 +00:05:35,936 --> 00:05:39,705 +examples of that in the demos and of course, modal, you can + +115 +00:05:39,707 --> 00:05:42,741 +do that as well. You also, if you have a view controller in + +116 +00:05:42,743 --> 00:05:44,710 +your hand, you actually have an instance of a view + +117 +00:05:44,712 --> 00:05:47,212 +controller like remember alert view controller, right? + +118 +00:05:47,214 --> 00:05:49,681 +You say new alert view controller and you get one, + +119 +00:05:49,683 --> 00:05:53,118 +now you have one. You can put it up using this method right + +120 +00:05:53,120 --> 00:05:56,455 +here, which we actually saw in one of the other demos, + +121 +00:05:56,457 --> 00:05:59,257 +alert demo there. Actually I don't know if I demoed it, + +122 +00:05:59,259 --> 00:06:01,660 +but we talked about it in alerts, which is present + +123 +00:06:01,662 --> 00:06:03,628 +view controller. And you just give it the view controller + +124 +00:06:03,630 --> 00:06:06,264 +that you have in your hand and whether you want it + +125 +00:06:06,266 --> 00:06:09,668 +to be an animated transition, which usually you do. And + +126 +00:06:09,670 --> 00:06:12,070 +then you just got a little handler here at the end, + +127 +00:06:12,072 --> 00:06:15,440 +that will get called when it has finished being presented. + +128 +00:06:15,442 --> 00:06:18,009 +You usually don't need that, but just in case, you do. + +129 +00:06:18,011 --> 00:06:20,178 +All right. So this is how you present something modally. + +130 +00:06:20,180 --> 00:06:23,115 +This is only for modalPresentations, all right? + +131 +00:06:23,117 --> 00:06:24,516 +If you have the view controller in your hand, + +132 +00:06:24,518 --> 00:06:28,453 +which is rare. Generally, it's things you got from iOS, + +133 +00:06:28,455 --> 00:06:30,922 +like maybe the camera view controller, or + +134 +00:06:30,924 --> 00:06:34,059 +the alert view controller, some things like that. + +135 +00:06:34,061 --> 00:06:37,462 +Notice that in horizontally regular environment, + +136 +00:06:37,464 --> 00:06:40,732 +horizontally regular, not compact. You there's + +137 +00:06:40,734 --> 00:06:44,169 +a modalPresentationStyle var in a view controller, that'll, + +138 +00:06:44,171 --> 00:06:47,305 +that'll specify basically how this view controller gets + +139 +00:06:47,307 --> 00:06:50,175 +presented when it gets presented modally. Does it get + +140 +00:06:50,177 --> 00:06:53,512 +presented full screen where it takes the whole full screen? + +141 +00:06:53,514 --> 00:06:57,382 +OverFullScreen which means, it goes over the whole screen but + +142 +00:06:57,384 --> 00:06:58,283 +it, the one behind, + +143 +00:06:58,285 --> 00:07:01,286 +whatever is existing on this screen is visible. So + +144 +00:07:01,288 --> 00:07:03,288 +if you had a clear view controller, + +145 +00:07:03,290 --> 00:07:03,989 +you'd be able to see through it. + +146 +00:07:03,991 --> 00:07:07,592 +So you have things underneath. Pop over, of course you guys + +147 +00:07:07,594 --> 00:07:10,462 +know what a pop over is. A pop over is just a modal, + +148 +00:07:10,464 --> 00:07:15,033 +a modal MVC, but it's kinda got some special presentation + +149 +00:07:15,035 --> 00:07:18,136 +characteristics. There's also form sheet and page sheet, + +150 +00:07:18,138 --> 00:07:21,339 +things like that, which kinda present in different ways. + +151 +00:07:21,341 --> 00:07:24,242 +You can play with those, by inspecting the segue in + +152 +00:07:24,244 --> 00:07:27,712 +the storyboard and choosing different presentation styles. + +153 +00:07:27,714 --> 00:07:31,283 +Note that in horizontally compact environments, however, + +154 +00:07:31,285 --> 00:07:35,754 +it's basically the iPhone in portrait. The system, when you + +155 +00:07:35,756 --> 00:07:40,091 +do the presentViewController will by default, + +156 +00:07:40,093 --> 00:07:42,327 +adapt to be full screen, okay? + +157 +00:07:42,329 --> 00:07:46,164 +So if you try to present something in form sheet mode, + +158 +00:07:46,166 --> 00:07:50,101 +okay? On an iPhone, it'll come up as full screen, cuz it'll + +159 +00:07:50,103 --> 00:07:54,406 +adapt to the fact that it's on the phone. It doesn't really + +160 +00:07:54,408 --> 00:07:58,844 +have enough width to do a form sheet for you, okay? + +161 +00:07:58,846 --> 00:08:02,047 +How do you prepare for a Modal segue? Nothing to see here, + +162 +00:08:02,049 --> 00:08:04,616 +okay? It's just like any other segue you've ever done. + +163 +00:08:04,618 --> 00:08:06,751 +Nothing special about it. Just check the identifier, + +164 +00:08:06,753 --> 00:08:09,321 +get the destination view controller and prepare it. + +165 +00:08:09,323 --> 00:08:12,958 +How do you hear back from a modal view controller? + +166 +00:08:12,960 --> 00:08:15,460 +You put something some up modally and it does something, + +167 +00:08:15,462 --> 00:08:18,230 +okay? You add to new contact, how do you hear back + +168 +00:08:18,232 --> 00:08:21,166 +with the results of what it did? Okay? Well, + +169 +00:08:21,168 --> 00:08:26,271 +there's a couple of ways to do this. One is that the add + +170 +00:08:26,273 --> 00:08:29,674 +contact thing might be putting the contact in a database, + +171 +00:08:29,676 --> 00:08:32,644 +some modal that is shared by the guy who put it up. + +172 +00:08:32,646 --> 00:08:35,113 +So then you don't need to do anything, okay. When the modal + +173 +00:08:35,115 --> 00:08:36,715 +thing gets dismissed, you'll come back and there'll be + +174 +00:08:36,717 --> 00:08:39,384 +something else in the database that wasn't there before. + +175 +00:08:39,386 --> 00:08:42,988 +Another way is using an unwind segue which I'm gonna talk + +176 +00:08:42,990 --> 00:08:45,891 +about in few slides here. And then another way is + +177 +00:08:45,893 --> 00:08:48,660 +delegation. And the reason we have to use delegation or + +178 +00:08:48,662 --> 00:08:51,396 +unwind or something like that is because when you present + +179 +00:08:51,398 --> 00:08:53,932 +a view controller modally, it's part of your view. + +180 +00:08:53,934 --> 00:08:56,701 +It's part of the presenting view controller's view. + +181 +00:08:56,703 --> 00:09:00,472 +So that thing can't talk back in any way, except for + +182 +00:09:00,474 --> 00:09:02,240 +those blind structured ways we talked about, + +183 +00:09:02,242 --> 00:09:07,245 +like delegation, okay? How do you dismiss a view controller, + +184 +00:09:07,247 --> 00:09:10,115 +right? So a view controller's up, and it's collecting + +185 +00:09:10,117 --> 00:09:12,584 +the new contact, and then the user puts Cancel or + +186 +00:09:12,586 --> 00:09:16,154 +Done, how do we make it go away? The answer is you ask + +187 +00:09:16,156 --> 00:09:19,424 +the presenting view controller to dismiss you, always + +188 +00:09:19,426 --> 00:09:22,928 +the presenting view controller dismisses you. All right? And + +189 +00:09:22,930 --> 00:09:26,164 +you send it the message dismissViewControllerAnimated + +190 +00:09:26,166 --> 00:09:27,432 +to the presenting view controller and + +191 +00:09:27,434 --> 00:09:31,069 +it's going to dismiss whatever modal view controller it has + +192 +00:09:31,071 --> 00:09:34,973 +presented, okay? So that's sent to the presenting. + +193 +00:09:34,975 --> 00:09:38,143 +I can't emphasize that enough. Now, in the old days, + +194 +00:09:38,145 --> 00:09:40,312 +people used to send it to the presented. + +195 +00:09:40,314 --> 00:09:41,846 +The API was a little bit different, okay? + +196 +00:09:41,848 --> 00:09:44,215 +And then sent it to the presented view controller, + +197 +00:09:44,217 --> 00:09:46,084 +the one that's actually up, okay? + +198 +00:09:46,086 --> 00:09:49,287 +And, that's wrong. For backwards compatibility, + +199 +00:09:49,289 --> 00:09:50,622 +if you sent it to the presented one, + +200 +00:09:50,624 --> 00:09:53,892 +and the presented one had not presented another one, + +201 +00:09:53,894 --> 00:09:56,561 +then it would dismiss it. But don't write your code to + +202 +00:09:56,563 --> 00:09:59,464 +depend on that kind of backwards compatibility mode. + +203 +00:09:59,466 --> 00:10:02,534 +When you wanna dismiss it, you send it to the presenting. + +204 +00:10:02,536 --> 00:10:05,937 +Now the great thing is that the presented has a var + +205 +00:10:05,939 --> 00:10:08,640 +called presenting view controller, which is the view + +206 +00:10:08,642 --> 00:10:11,009 +controller that presented it. So it's very easy for + +207 +00:10:11,011 --> 00:10:13,778 +the presented one to dismiss itself by asking + +208 +00:10:13,780 --> 00:10:17,682 +its presenting view controller to dismiss it. You see. + +209 +00:10:17,684 --> 00:10:20,251 +But that's the way you wanna write that code. + +210 +00:10:20,253 --> 00:10:22,420 +Okay, if you do an unwind segue, + +211 +00:10:22,422 --> 00:10:24,322 +again, which I'm gonna talk about in a few slides, + +212 +00:10:24,324 --> 00:10:26,791 +it automatically dismisses. So when you unwind, + +213 +00:10:26,793 --> 00:10:29,094 +you don't have to call dismissViewController. + +214 +00:10:29,096 --> 00:10:30,195 +Just automatically dismisses. So + +215 +00:10:30,197 --> 00:10:33,031 +we're talking about unwinding in a second. All right, + +216 +00:10:33,033 --> 00:10:37,902 +so in addition to how the modal view controller appears, + +217 +00:10:37,904 --> 00:10:39,704 +like form sheet or popover or whatever, + +218 +00:10:39,706 --> 00:10:42,440 +there's also how it gets transitioned onto the screen, + +219 +00:10:42,442 --> 00:10:45,977 +what animation gets used. Okay, so, CoverVertical is + +220 +00:10:45,979 --> 00:10:48,313 +the slides up from the bottom, FlipHorizontal, + +221 +00:10:48,315 --> 00:10:50,248 +exactly what you would think, the presented and + +222 +00:10:50,250 --> 00:10:53,952 +the presenting flip, are on like two sides of a card and + +223 +00:10:53,954 --> 00:10:54,319 +it flips over. + +224 +00:10:54,321 --> 00:10:56,955 +You got CrossDissolve which is all between the two. + +225 +00:10:56,957 --> 00:11:00,792 +Even PartialCurl which will partially curl a presenting + +226 +00:11:00,794 --> 00:11:05,263 +one up showing the presented behind it. Kind of just at + +227 +00:11:05,265 --> 00:11:06,731 +the bottom. It's kind of looks really cool. + +228 +00:11:06,733 --> 00:11:08,466 +You see it sometimes with map applications and + +229 +00:11:08,468 --> 00:11:13,071 +stuff you curl the map up and there's something underneath. + +230 +00:11:14,274 --> 00:11:17,275 +All right, let's talk about that wi, unwind segue. + +231 +00:11:17,277 --> 00:11:18,243 +Right, you have these MVCs, + +232 +00:11:18,245 --> 00:11:21,012 +they wanna communicate back, or they wanna jump back. + +233 +00:11:21,014 --> 00:11:23,248 +Maybe, something's on a navigation stack and + +234 +00:11:23,250 --> 00:11:26,317 +wants to jump back farther than just one pop, okay? + +235 +00:11:26,319 --> 00:11:27,752 +You can do all this with an unwind. + +236 +00:11:27,754 --> 00:11:31,423 +Now, unwind segues are weird because they violate the thing + +237 +00:11:31,425 --> 00:11:32,924 +I told you would never violate it, + +238 +00:11:32,926 --> 00:11:37,062 +which is that segues always create a new MVC. Okay, and + +239 +00:11:37,064 --> 00:11:41,132 +that's generally true if you modally segue or show segue or + +240 +00:11:41,134 --> 00:11:42,701 +any of these other kinds of segues, + +241 +00:11:42,703 --> 00:11:46,604 +it creates a new MVC every time except unwind. Because + +242 +00:11:46,606 --> 00:11:50,375 +unwind is gonna segue back to somebody who presented you, + +243 +00:11:50,377 --> 00:11:52,844 +maybe not the guy who immediately presented to you, + +244 +00:11:52,846 --> 00:11:54,279 +maybe somebody who presented to the guy + +245 +00:11:54,281 --> 00:11:54,779 +who presented to you but + +246 +00:11:54,781 --> 00:11:57,282 +you're gonna be going back to an existing view controller. + +247 +00:11:57,284 --> 00:12:01,786 +You're gonna unwind. Okay, your view controllers. + +248 +00:12:01,788 --> 00:12:03,822 +What's it good for? Like I said, good for + +249 +00:12:03,824 --> 00:12:06,925 +communicating back information after a modal one is done, + +250 +00:12:06,927 --> 00:12:09,561 +and also good for jumping back up the stack of cards in + +251 +00:12:09,563 --> 00:12:13,498 +the navigation controller more than one step, okay? + +252 +00:12:13,500 --> 00:12:15,767 +Because it can go back to guys, who presented guys, + +253 +00:12:15,769 --> 00:12:18,470 +who presented guys so it can jump all the way back. + +254 +00:12:18,472 --> 00:12:20,805 +How does it work? Okay, so instead of + +255 +00:12:20,807 --> 00:12:24,709 +Ctrl+dragging to another MVC to set up this segue which is + +256 +00:12:24,711 --> 00:12:27,545 +what you usually do, you actually Ctrl+drag to this + +257 +00:12:27,547 --> 00:12:30,181 +little button at the top. It's kinda reddish. + +258 +00:12:30,183 --> 00:12:34,185 +The Exit button. Okay, so if I have this row in this table + +259 +00:12:34,187 --> 00:12:37,622 +right here and when you click on it, it wants to unwind and + +260 +00:12:37,624 --> 00:12:41,025 +go back to one of the MVCs that presented this MVC, + +261 +00:12:41,027 --> 00:12:45,163 +you just Ctrl+drag up to this little exit. Now when you do + +262 +00:12:45,165 --> 00:12:49,501 +that, it's gonna show you a list of methods that + +263 +00:12:49,503 --> 00:12:53,805 +are implemented by other MVCs in your app, okay? They're + +264 +00:12:53,807 --> 00:12:57,342 +special, and I'll show you what makes them special but + +265 +00:12:57,344 --> 00:13:00,879 +these special things will appear in this list. + +266 +00:13:00,881 --> 00:13:04,549 +And all you do is pick which one you want. Then when you do + +267 +00:13:04,551 --> 00:13:07,685 +the segue, it will start looking up the list of MVC's + +268 +00:13:07,687 --> 00:13:09,354 +that presented you, and the one that presented that, and + +269 +00:13:09,356 --> 00:13:11,523 +the one that presented that until it finds that method. + +270 +00:13:11,525 --> 00:13:14,359 +And it will dismiss all the way back to that one and + +271 +00:13:14,361 --> 00:13:19,330 +call this method, okay? So let me show you some more + +272 +00:13:19,332 --> 00:13:22,801 +pictures to make this a little bit clearer right here. + +273 +00:13:22,803 --> 00:13:26,104 +So this go back method right here, okay, + +274 +00:13:26,106 --> 00:13:28,306 +I want, I connected to exit and + +275 +00:13:28,308 --> 00:13:28,740 +I have to go back. + +276 +00:13:28,742 --> 00:13:32,110 +Go back let's say is in the guy who directly presented me. + +277 +00:13:32,112 --> 00:13:34,712 +He could be farther up the stack but let's say he's right + +278 +00:13:34,714 --> 00:13:37,282 +here. And here's this go back method right here. Now, + +279 +00:13:37,284 --> 00:13:40,552 +what's special about this go back method in this presenter? + +280 +00:13:40,554 --> 00:13:44,355 +Well, one thing is it has to be marked IBAction, okay? + +281 +00:13:44,357 --> 00:13:47,292 +So if it has IBAction. And the second thing is, + +282 +00:13:47,294 --> 00:13:51,162 +the argument has to be a UIStoryboardSegue. So + +283 +00:13:51,164 --> 00:13:53,731 +any method that's, is marked IBAction and + +284 +00:13:53,733 --> 00:13:57,802 +has UIStoryboardSegue as the argument is gonna appear in + +285 +00:13:57,804 --> 00:14:02,240 +this list. Okay, now this IBAction, + +286 +00:14:02,242 --> 00:14:06,377 +once you kind of pick the one you want. + +287 +00:14:06,379 --> 00:14:09,314 +This segue is gonna happen and it's still gonna be a normal + +288 +00:14:09,316 --> 00:14:10,982 +segue and then it's gonna have prepare. + +289 +00:14:10,984 --> 00:14:13,985 +Now the prepare, okay, here's the prepare for segue. + +290 +00:14:13,987 --> 00:14:17,689 +It's going to be in the aah MVC that you wired the exit + +291 +00:14:17,691 --> 00:14:20,725 +button up to, the one on the right here. Okay, + +292 +00:14:20,727 --> 00:14:23,027 +so it lives down in there. And it gets to prepare for + +293 +00:14:23,029 --> 00:14:26,564 +this segue. The segue is gonna come back to this presenter. + +294 +00:14:26,566 --> 00:14:28,967 +So, the destination view controller, + +295 +00:14:28,969 --> 00:14:33,872 +here, is the presenter. The source view controller, + +296 +00:14:33,874 --> 00:14:34,906 +which you haven't seen yet, + +297 +00:14:34,908 --> 00:14:38,710 +in previous segues, is the thing on the right, okay? + +298 +00:14:38,712 --> 00:14:42,180 +The thing it's segueing from. That's the source, + +299 +00:14:42,182 --> 00:14:46,351 +this is the destination, okay? Make sense? And + +300 +00:14:46,353 --> 00:14:49,220 +when this happens, okay, when the segue happens, + +301 +00:14:49,222 --> 00:14:52,156 +you'll be dismissed, right? The source one + +302 +00:14:52,158 --> 00:14:55,226 +will be dismissed. And again, it doesn't just have to + +303 +00:14:55,228 --> 00:14:57,829 +go one level up, it could go up the stack of the navigation + +304 +00:14:57,831 --> 00:15:00,431 +controller things. Or if you had four or five modals in + +305 +00:15:00,433 --> 00:15:02,634 +a row, it could jump all the way back, it's perfectly fine. + +306 +00:15:02,636 --> 00:15:07,038 +It's just whoever implements the method. All right? + +307 +00:15:07,040 --> 00:15:10,341 +Now let's talk another kind of segue, popovers, okay? + +308 +00:15:10,343 --> 00:15:11,009 +You've all seen the popover. + +309 +00:15:11,011 --> 00:15:13,544 +Here's an example of popover here on the right. + +310 +00:15:13,546 --> 00:15:16,247 +This is probably some kind of Search for Appointment to + +311 +00:15:16,249 --> 00:15:21,486 +popover, okay? So this MVC just leaves in here. + +312 +00:15:21,488 --> 00:15:23,721 +And it's being presented modally, okay? + +313 +00:15:23,723 --> 00:15:26,958 +It's just that it presents in a way that looks like this, + +314 +00:15:26,960 --> 00:15:29,961 +like it's in a pop-over. And the popover of course has + +315 +00:15:29,963 --> 00:15:32,196 +a little arrow at the top, a little white arrow, + +316 +00:15:32,198 --> 00:15:35,767 +you can see it, that points to the thing, the UI element that + +317 +00:15:35,769 --> 00:15:40,405 +caused it to pop up. Usually that's a bar button item, but + +318 +00:15:40,407 --> 00:15:43,341 +it could also just be an arbitrary rectangle inside + +319 +00:15:43,343 --> 00:15:47,712 +some view somewhere, okay? This area out here, okay, + +320 +00:15:47,714 --> 00:15:51,015 +everywhere else except for this popover and + +321 +00:15:51,017 --> 00:15:54,652 +the keyboard is grayed out. If you click there, + +322 +00:15:54,654 --> 00:15:58,556 +it will dismiss this popover. So the one difference between + +323 +00:15:58,558 --> 00:16:02,293 +popover and other kinda modal one is that popovers are easy + +324 +00:16:02,295 --> 00:16:05,964 +to dismiss. Just click outside of them, you'll dismiss, so + +325 +00:16:05,966 --> 00:16:08,633 +you don't need a cancel button in a popover or + +326 +00:16:08,635 --> 00:16:11,502 +modal popover. But it's still modal in that obviously you + +327 +00:16:11,504 --> 00:16:13,738 +can't do anything in that grayed out area. + +328 +00:16:13,740 --> 00:16:16,007 +You can only do what this search for + +329 +00:16:16,009 --> 00:16:18,409 +appointment MBC wants to do right now. + +330 +00:16:18,411 --> 00:16:21,112 +Okay, so it's still a modal, it just looks different. + +331 +00:16:21,114 --> 00:16:26,317 +Popover is just a presentation style basically for modal. So + +332 +00:16:26,319 --> 00:16:29,320 +popovers, you think of a popover's kind of like + +333 +00:16:29,322 --> 00:16:32,824 +a navigational controller or split view controller, a tab + +334 +00:16:32,826 --> 00:16:36,294 +bar because it's putting a view controller inside another + +335 +00:16:36,296 --> 00:16:39,497 +another view controller, but it's not. You should think of + +336 +00:16:39,499 --> 00:16:44,569 +popover just as a presentation style. Dial for modal, okay? + +337 +00:16:44,571 --> 00:16:48,373 +So segue into a popover is setup the same way that you + +338 +00:16:48,375 --> 00:16:51,642 +setup a oni modal one, it's just that when you drag over, + +339 +00:16:51,644 --> 00:16:56,080 +you're gonna pick popover instead of modal, okay? When + +340 +00:16:56,082 --> 00:16:59,350 +you're in the storyboard you drag over. Now, an important + +341 +00:16:59,352 --> 00:17:02,253 +thing to note when you prepare for a popover segue, + +342 +00:17:02,255 --> 00:17:04,455 +this is what's different between a popover and + +343 +00:17:04,457 --> 00:17:10,461 +immodal encode, okay? When you prepare all presentations of + +344 +00:17:10,463 --> 00:17:14,265 +any kind of segue are done by a UI presentation controller. + +345 +00:17:14,267 --> 00:17:17,335 +You don't see this, I'm not really talking about this + +346 +00:17:17,337 --> 00:17:20,071 +in this class, it's not really kind of a introductory + +347 +00:17:20,073 --> 00:17:24,342 +material. But, the popover one has a sub class of that called + +348 +00:17:24,344 --> 00:17:26,244 +UI popover presentation controller, + +349 +00:17:26,246 --> 00:17:27,278 +and it's in the thing that knows + +350 +00:17:27,280 --> 00:17:28,613 +how to present it as a popover. + +351 +00:17:28,615 --> 00:17:31,516 +So it's the thing that knows, for example, where to have + +352 +00:17:31,518 --> 00:17:35,053 +the little popover thing point, okay. That's something + +353 +00:17:35,055 --> 00:17:39,123 +that that popover presentation controller knows about. So in + +354 +00:17:39,125 --> 00:17:42,360 +your prepare for segue, you're gonna get this UI popover + +355 +00:17:42,362 --> 00:17:44,462 +presentation controller and I'll show you how to do that. + +356 +00:17:44,464 --> 00:17:47,398 +And you're going to use it to configure how the popover + +357 +00:17:47,400 --> 00:17:51,869 +presents, okay? Now in addition to setting things + +358 +00:17:51,871 --> 00:17:53,805 +like where the popover's arrow can point, + +359 +00:17:53,807 --> 00:17:57,008 +you can also control things like how the popover adapts + +360 +00:17:57,010 --> 00:18:00,912 +to different size classes, okay? And we'll talk about + +361 +00:18:00,914 --> 00:18:04,615 +that in a second too. So here's the prepare for segue, + +362 +00:18:04,617 --> 00:18:06,384 +the prepare for a popover, okay? + +363 +00:18:06,386 --> 00:18:09,954 +All the green, except for what's in this yellow if + +364 +00:18:09,956 --> 00:18:13,524 +statement right here is the same as any other prepare. But + +365 +00:18:13,526 --> 00:18:14,592 +when we get down to the bottom here, + +366 +00:18:14,594 --> 00:18:17,295 +we're gonna get that popover presentation controller by + +367 +00:18:17,297 --> 00:18:20,698 +asking the view controller that we're putting up modally. + +368 +00:18:20,700 --> 00:18:24,402 +Please give me your popover presentation controller, + +369 +00:18:24,404 --> 00:18:27,271 +okay? So that view controller has the popover presentation + +370 +00:18:27,273 --> 00:18:30,475 +going. We get it. Once we have it, we can do things like + +371 +00:18:30,477 --> 00:18:33,044 +configure it like the permitted arrow directions. + +372 +00:18:33,046 --> 00:18:35,980 +Which direction we want the arrow to be? We can also + +373 +00:18:35,982 --> 00:18:40,118 +specify things like where the arrows are pointing, + +374 +00:18:40,120 --> 00:18:40,852 +all that kind of stuff. + +375 +00:18:40,854 --> 00:18:44,021 +Okay, everything you would imagine a popover needs to be + +376 +00:18:44,023 --> 00:18:47,158 +configured with. All right, now also importantly, + +377 +00:18:47,160 --> 00:18:51,863 +we can set that presentation controllers delegate, okay? + +378 +00:18:51,865 --> 00:18:54,365 +And with that delegate we control a little bit more + +379 +00:18:54,367 --> 00:18:56,701 +about how the popover works. So let's talk about that. + +380 +00:18:56,703 --> 00:19:00,004 +What can we do with the delegate? One thing we can do + +381 +00:19:00,006 --> 00:19:04,942 +is find out when that popover was dismissed, okay? So + +382 +00:19:04,944 --> 00:19:06,144 +the delegate will be sent this message, + +383 +00:19:06,146 --> 00:19:08,946 +popoverPresentationController- DidDismissPopover. + +384 +00:19:08,948 --> 00:19:11,782 +Did dismiss popover. Okay, so that's nice to be able to + +385 +00:19:11,784 --> 00:19:14,919 +know when that popover was dismissed. Another thing is we + +386 +00:19:14,921 --> 00:19:18,623 +can control the adaptation behavior when we're in + +387 +00:19:18,625 --> 00:19:22,193 +different size classes like horizontally compact, + +388 +00:19:22,195 --> 00:19:25,029 +okay? So when a popover comes up, as you can + +389 +00:19:25,031 --> 00:19:28,032 +imagine, maybe it wouldn't fit in a horizontally compact + +390 +00:19:28,034 --> 00:19:30,535 +environment unless it's kind of the small popover. + +391 +00:19:30,537 --> 00:19:34,839 +So by default, the system adapts to full screen. + +392 +00:19:34,841 --> 00:19:37,642 +So if you have a popover segue and it's on horizontally + +393 +00:19:37,644 --> 00:19:41,812 +compact, it gets changed to modal full screen. So it'll + +394 +00:19:41,814 --> 00:19:44,182 +take over the whole screen, slide up from the bottom. + +395 +00:19:44,184 --> 00:19:46,751 +Okay, now you might now want that. Maybe it is a small + +396 +00:19:46,753 --> 00:19:49,687 +little popover and you do want it to be a pop over on iPhone + +397 +00:19:49,689 --> 00:19:52,590 +and you can control that. And here's how you do that. + +398 +00:19:52,592 --> 00:19:55,526 +There is a method. Okay, this is a popover. This is actually + +399 +00:19:55,528 --> 00:19:59,397 +a presentation controller delegate method. And + +400 +00:19:59,399 --> 00:20:01,832 +you can see it just sends you the controller here and + +401 +00:20:01,834 --> 00:20:05,903 +a traitCollection. So that's the size class is right here + +402 +00:20:05,905 --> 00:20:07,905 +and you're gonna return a presentation style. + +403 +00:20:07,907 --> 00:20:10,975 +Now, if you don't implement this delegation method, then + +404 +00:20:10,977 --> 00:20:14,278 +in horizontally compact, it returns full screen otherwise, + +405 +00:20:14,280 --> 00:20:16,714 +it returns whatever it was setup in the storyboard, + +406 +00:20:16,716 --> 00:20:19,217 +popover or form sheet or whatever. But + +407 +00:20:19,219 --> 00:20:21,919 +if you do implement it, you could return for example UI + +408 +00:20:21,921 --> 00:20:25,823 +modal presentation style none which means don't adapt. + +409 +00:20:25,825 --> 00:20:29,093 +This is asking for, how do I adapt to this trait + +410 +00:20:29,095 --> 00:20:31,796 +collection. If you say none, that means don't adapt. + +411 +00:20:31,798 --> 00:20:34,031 +Just do the same thing on every single platform. + +412 +00:20:34,033 --> 00:20:37,068 +Okay, and so if you do this, then your popover will appear + +413 +00:20:37,070 --> 00:20:40,071 +as a popover on your iPhone. Look just like on an iPad but + +414 +00:20:40,073 --> 00:20:43,140 +it better be small coz it didn't have a lot of room. + +415 +00:20:43,142 --> 00:20:47,178 +So this is how you can control that adaptation behavior, + +416 +00:20:47,180 --> 00:20:49,747 +okay. But here's a problem, let's say you + +417 +00:20:49,749 --> 00:20:52,316 +do that, okay, let's say you don't do that. Let's say + +418 +00:20:52,318 --> 00:20:54,885 +the popover is too big and it comes up full screen, + +419 +00:20:54,887 --> 00:20:59,624 +how do you dismiss that popover, okay? Because it used + +420 +00:20:59,626 --> 00:21:01,592 +to be a popover I could click somewhere else and + +421 +00:21:01,594 --> 00:21:03,494 +it will disappear. But now it's full screen. + +422 +00:21:03,496 --> 00:21:06,464 +I can't click anywhere else. How do I dismiss it? Okay, + +423 +00:21:06,466 --> 00:21:08,599 +that's a problem. What would be really cool, + +424 +00:21:08,601 --> 00:21:11,335 +is if you could put it inside a navigation controller and + +425 +00:21:11,337 --> 00:21:15,740 +then add a little done button, right at the top? And + +426 +00:21:15,742 --> 00:21:18,242 +this method is how you do that. So, if you implement + +427 +00:21:18,244 --> 00:21:20,911 +the delegate of the popover presentation controller, and + +428 +00:21:20,913 --> 00:21:22,713 +you implement this thing, view controller for + +429 +00:21:22,715 --> 00:21:25,650 +adapter presentation style, it allows you to return + +430 +00:21:25,652 --> 00:21:30,655 +a different view controller to present. For example, + +431 +00:21:30,657 --> 00:21:33,057 +you might, preser, present, return a navigation + +432 +00:21:33,059 --> 00:21:36,994 +controller. Whose visible view controller is, the actual view + +433 +00:21:36,996 --> 00:21:39,897 +controller that was inside the popover, you see. And + +434 +00:21:39,899 --> 00:21:42,633 +you could add a done button to it or whatever you want. So + +435 +00:21:42,635 --> 00:21:44,435 +here you can return, if you return nil here + +436 +00:21:44,437 --> 00:21:47,338 +it's going to just return the thing that was inside, + +437 +00:21:47,340 --> 00:21:48,339 +gonna be inside the popover. + +438 +00:21:48,341 --> 00:21:50,374 +But if you return the navigation controller or + +439 +00:21:50,376 --> 00:21:53,311 +whatever, it'll put that up In the modal adapted. And this is + +440 +00:21:53,313 --> 00:21:56,280 +only happening in the adapted case, right? View control for + +441 +00:21:56,282 --> 00:22:01,652 +adapted presentation style, okay? All right, + +442 +00:22:01,654 --> 00:22:04,789 +very important issue about popover is its size, okay? + +443 +00:22:04,791 --> 00:22:07,625 +iOS implements its size in a very object-jointed way, + +444 +00:22:07,627 --> 00:22:10,828 +which is that when you have an MVC that's gonna be put up as + +445 +00:22:10,830 --> 00:22:14,131 +a popover, the system asks that MVC what size would + +446 +00:22:14,133 --> 00:22:15,466 +you prefer it to be? + +447 +00:22:15,468 --> 00:22:18,102 +Okay, because that MVC obviously knows what the best + +448 +00:22:18,104 --> 00:22:22,139 +size for it to be is, and it does that via this var + +449 +00:22:22,141 --> 00:22:25,643 +preferredContentSize is a CGSize and you can either + +450 +00:22:25,645 --> 00:22:29,947 +set this preferredContectSize. The MVC can set its + +451 +00:22:29,949 --> 00:22:32,550 +own preferredContectSize to something reasonable or + +452 +00:22:32,552 --> 00:22:34,652 +you could actually even override it. And + +453 +00:22:34,654 --> 00:22:38,789 +have it return its correct size, its prefered size. + +454 +00:22:38,791 --> 00:22:42,059 +It's called preferred by the way because, obviously + +455 +00:22:42,061 --> 00:22:44,395 +the system will try to fit it on screen but if, for + +456 +00:22:44,397 --> 00:22:47,298 +example, it's on horizontally compact and the adaptive thing + +457 +00:22:47,300 --> 00:22:49,734 +is turned off then it might have to jam it in there, + +458 +00:22:49,736 --> 00:22:51,769 +it might have to be a little smaller than preferred wants + +459 +00:22:51,771 --> 00:22:55,973 +it to be, kay? So this is not guaranteed to be this size, + +460 +00:22:55,975 --> 00:23:00,878 +this size is preferred. Okay, the last segue I'm gonna talk + +461 +00:23:00,880 --> 00:23:03,781 +about is embed segues, okay? These are really, + +462 +00:23:03,783 --> 00:23:07,785 +really cool segues. Basically you could take an MVC, + +463 +00:23:07,787 --> 00:23:10,321 +take its view, you know, the top level view, and + +464 +00:23:10,323 --> 00:23:14,225 +put it as a view inside the view hierarchy of another MVC. + +465 +00:23:14,227 --> 00:23:17,061 +Okay it'll look just a view in another MVC, it's just that, + +466 +00:23:17,063 --> 00:23:19,130 +it's completely controlled by an MVC, + +467 +00:23:19,132 --> 00:23:21,699 +okay? Really cool that's why it's called embedded. + +468 +00:23:21,701 --> 00:23:24,301 +You're embedding an MVC inside of another one. + +469 +00:23:24,303 --> 00:23:25,736 +Xcode makes it really easy to do this. + +470 +00:23:25,738 --> 00:23:30,174 +Just go down to your little object pallet down there where + +471 +00:23:30,176 --> 00:23:31,809 +you get your buttons and stuff. And look for + +472 +00:23:31,811 --> 00:23:35,646 +container view and drag that into the place that you want + +473 +00:23:35,648 --> 00:23:38,215 +this thing to be embedded. It will look just like a view, + +474 +00:23:38,217 --> 00:23:40,184 +you can do auto layout constraints on it. + +475 +00:23:40,186 --> 00:23:42,653 +You can put it as a sub-view of anything else you want. + +476 +00:23:42,655 --> 00:23:45,656 +It's just a view, okay. And when you do it, + +477 +00:23:45,658 --> 00:23:50,060 +you're gonna see this kind of cool look where it puts what + +478 +00:23:50,062 --> 00:23:51,529 +looks like a Segue way thing. + +479 +00:23:51,531 --> 00:23:53,998 +Okay, here's the thing in the container, what I dragged out. + +480 +00:23:54,000 --> 00:23:57,535 +This segue right here and here's the NVC. Okay so + +481 +00:23:57,537 --> 00:24:00,905 +here's the normal NVC like in your storyboard anywhere else, + +482 +00:24:00,907 --> 00:24:03,874 +and it's got this little segue here, so kinda seem like + +483 +00:24:03,876 --> 00:24:06,177 +a segue and it is in the sense kinda segue to it. + +484 +00:24:06,179 --> 00:24:09,380 +It's just that instead of doing it modelly or something + +485 +00:24:09,382 --> 00:24:12,383 +that, it's just going to put its view right in here. + +486 +00:24:12,385 --> 00:24:16,320 +Okay, make sense and you can prepare for that segue, + +487 +00:24:16,322 --> 00:24:20,224 +it's a perfectly normal segue. One thing to be careful + +488 +00:24:20,226 --> 00:24:22,660 +about this though is the View Loading Timing. + +489 +00:24:22,662 --> 00:24:24,662 +Remember that when you're in prepare for segue, + +490 +00:24:24,664 --> 00:24:27,431 +none of the outlets of the MVC are set. And that's true with + +491 +00:24:27,433 --> 00:24:30,067 +embed as well, all right? So might have this embed segue, + +492 +00:24:30,069 --> 00:24:33,003 +has all this cool UI but none of its outlets are set up. So + +493 +00:24:33,005 --> 00:24:35,606 +a lot of times in the embed, when you're preparing for + +494 +00:24:35,608 --> 00:24:38,509 +an embed segue, you're just grabbing the MVC and + +495 +00:24:38,511 --> 00:24:40,377 +holding onto it with a pointer. And + +496 +00:24:40,379 --> 00:24:42,613 +then later like in your own viewDidLoad, + +497 +00:24:42,615 --> 00:24:46,283 +okay your MVC will be loaded by then, then you can go and + +498 +00:24:46,285 --> 00:24:49,153 +set whatever you want to the embayed, the embedded thing to + +499 +00:24:49,155 --> 00:24:52,189 +look like okay. So just be careful of that. + +500 +00:24:52,191 --> 00:24:55,259 +It's just standard thing here that prepare for + +501 +00:24:55,261 --> 00:24:59,230 +segue outlets aren't set in the destination MVC but for + +502 +00:24:59,232 --> 00:25:02,566 +embed it comes, it's even more obvious, kinda, + +503 +00:25:02,568 --> 00:25:07,571 +it bites you more often. Okay, so that's segues. Okay, + +504 +00:25:07,573 --> 00:25:10,741 +that's all the segues there are. Okay, Ben, now you can + +505 +00:25:10,743 --> 00:25:14,011 +cover. Yeah, question? >> So, so in, in that segues, + +506 +00:25:14,013 --> 00:25:16,814 +if you have an existing view controller, + +507 +00:25:16,816 --> 00:25:18,816 +can you connect into the inside or + +508 +00:25:18,818 --> 00:25:21,852 +does it have to look funny like, you know? + +509 +00:25:21,854 --> 00:25:22,887 +>> Yeah so the question is can + +510 +00:25:22,889 --> 00:25:26,190 +I connect just a regular mvc from somewhere like maybe my + +511 +00:25:26,192 --> 00:25:29,059 +Cassini image view controller for example. It's just + +512 +00:25:29,061 --> 00:25:31,328 +sitting around there. Could I embed it? And the answer is + +513 +00:25:31,330 --> 00:25:35,199 +yes you can. Okay the mvc has embedded nothing special about + +514 +00:25:35,201 --> 00:25:39,803 +it whatsoever okay it can be embedded just as easily. + +515 +00:25:40,206 --> 00:25:43,774 +All right. Core Location is my next topic. + +516 +00:25:43,776 --> 00:25:45,309 +Okay we're done with segues now we're moving on to + +517 +00:25:45,311 --> 00:25:49,413 +Core Location and map kit here. So Core Location and map + +518 +00:25:49,415 --> 00:25:53,417 +kit are really two part pieces of the same puzzle here. + +519 +00:25:53,419 --> 00:25:57,121 +Core Location is the non-UI way to find out about your + +520 +00:25:57,123 --> 00:26:01,258 +location. Okay? And then map kit is the bunch of UI to show + +521 +00:26:01,260 --> 00:26:04,028 +your location on maps and stuff. So when you talk about + +522 +00:26:04,030 --> 00:26:06,297 +correlation first because it has a lot of the intrinsic + +523 +00:26:06,299 --> 00:26:09,099 +stuff that you need to understand the map kit stuff. + +524 +00:26:09,101 --> 00:26:13,537 +All right. The basic object in core location is called + +525 +00:26:13,539 --> 00:26:17,641 +a CLLocation. Core location, location. CLLocation has + +526 +00:26:17,643 --> 00:26:21,145 +the coordinate latitude and longitude, altitude, + +527 +00:26:21,147 --> 00:26:24,481 +the horizontal and vertical accuracy of this location, + +528 +00:26:24,483 --> 00:26:27,551 +because sometimes depending on how you got this location, + +529 +00:26:27,553 --> 00:26:28,552 +it might be highly accurate, + +530 +00:26:28,554 --> 00:26:29,887 +you know, within a meter or so, or + +531 +00:26:29,889 --> 00:26:32,222 +might be very inaccurate, maybe it's a kilometer. + +532 +00:26:32,224 --> 00:26:35,459 +Okay? Timestamp, when was this thing was taken, you'll see + +533 +00:26:35,461 --> 00:26:39,029 +that that's really important. A speed if the system detected + +534 +00:26:39,031 --> 00:26:42,266 +that you were moving at this time that this thing was + +535 +00:26:42,268 --> 00:26:45,970 +taken, and a course will tell you what direction you were + +536 +00:26:45,972 --> 00:26:50,007 +headed in if it detects that you were moving at this point. + +537 +00:26:50,009 --> 00:26:55,179 +So that's the basic collection of stuff is in CLLocation. + +538 +00:26:55,181 --> 00:26:58,248 +The CL, coordinate, this coordinate thing right here is + +539 +00:26:58,250 --> 00:27:02,019 +a CLLocationCOordinate2D which is just a latitude and + +540 +00:27:02,021 --> 00:27:03,253 +a longitude struct. + +541 +00:27:03,255 --> 00:27:06,023 +The altitude is a CLLocationDistance, + +542 +00:27:06,025 --> 00:27:10,594 +which is meters. Okay? Now let's talk about + +543 +00:27:10,596 --> 00:27:14,932 +the accuracy thing, okay? When you are asking for + +544 +00:27:14,934 --> 00:27:18,302 +a location and when you get a location, in both cases, + +545 +00:27:18,304 --> 00:27:20,471 +you're gonna specify an accuracy, okay? + +546 +00:27:20,473 --> 00:27:23,240 +Specifying the accuracy is going to determine what + +547 +00:27:23,242 --> 00:27:25,976 +mechanism your device uses to get the accuracy. And + +548 +00:27:25,978 --> 00:27:29,380 +then when you get the accuracy back It tells you, kind of, + +549 +00:27:29,382 --> 00:27:32,416 +how it got it, somewhat. Okay, so, we're a little bit + +550 +00:27:32,418 --> 00:27:35,486 +abstracting the hardware away from the concept of + +551 +00:27:35,488 --> 00:27:38,889 +an accurate measurement of location. Here + +552 +00:27:38,891 --> 00:27:41,892 +are the different accuracies that it can have here, + +553 +00:27:41,894 --> 00:27:42,393 +best for navigation, + +554 +00:27:42,395 --> 00:27:45,129 +best nearest ten meters, hundred meters, kilometer, + +555 +00:27:45,131 --> 00:27:49,266 +or three kilometers and as you can imagine best for + +556 +00:27:49,268 --> 00:27:51,535 +navigation. It's really really really really accurate. + +557 +00:27:51,537 --> 00:27:55,639 +It's also really really really uses a lot of battery, okay. + +558 +00:27:55,641 --> 00:27:58,809 +And basically you can almost rename these things as + +559 +00:27:58,811 --> 00:27:59,810 +lots of battery usage, + +560 +00:27:59,812 --> 00:28:02,813 +a little bit less, medium battery usage, not so + +561 +00:28:02,815 --> 00:28:05,883 +much battery usage, very very battery efficient by the time + +562 +00:28:05,885 --> 00:28:09,453 +you get to the bottom. Okay? It's really batteries are big + +563 +00:28:09,455 --> 00:28:12,322 +deal when it comes to getting your location. Now, + +564 +00:28:12,324 --> 00:28:15,926 +how does the system get these different accuracy locations? + +565 +00:28:15,928 --> 00:28:19,129 +Well, there's three different ways really at least for + +566 +00:28:19,131 --> 00:28:21,331 +now that the system could get location and + +567 +00:28:21,333 --> 00:28:23,333 +you don't know which one is using. Okay, + +568 +00:28:23,335 --> 00:28:25,836 +all you get to do is specify the accuracy you want and + +569 +00:28:25,838 --> 00:28:28,472 +it will get the locations as best it can and re-tell you + +570 +00:28:28,474 --> 00:28:32,710 +what accuracy it got. But the three ways it knows how to do + +571 +00:28:32,712 --> 00:28:37,981 +are GPS which is very accurate and uses a lot of power. + +572 +00:28:37,983 --> 00:28:42,519 +Okay, then there's WiFi nodes. Believe it or not your phone + +573 +00:28:42,521 --> 00:28:45,689 +can, as you walk around, see what WiFi nodes are around. + +574 +00:28:45,691 --> 00:28:48,358 +It's got a huge database on the network of all the WiFi + +575 +00:28:48,360 --> 00:28:50,828 +nodes and where they are. And so based on which ones + +576 +00:28:50,830 --> 00:28:54,031 +are close to you, which ones you're getting good signal, + +577 +00:28:54,033 --> 00:28:56,266 +it can figure our generally where you are. + +578 +00:28:56,268 --> 00:28:57,701 +Which is kind of a cool feature, right? + +579 +00:28:57,703 --> 00:29:00,571 +Pretty low power, WiFi is fairly low power not as + +580 +00:29:00,573 --> 00:29:04,074 +low-power as cellular towers which is the next one, and, + +581 +00:29:04,076 --> 00:29:07,544 +but certainly a lot less power than doing GPS. And so, + +582 +00:29:07,546 --> 00:29:10,380 +it can find, you know, these kind of medium accuracies + +583 +00:29:10,382 --> 00:29:12,616 +by doing that. And in fact, if you walk around at Stanford, + +584 +00:29:12,618 --> 00:29:15,352 +it can be very accurate because there's an incredible + +585 +00:29:15,354 --> 00:29:17,688 +number of WiFi nodes around Stanford campus. You + +586 +00:29:17,690 --> 00:29:20,758 +are probably in range of 50 of them at almost given time. + +587 +00:29:20,760 --> 00:29:23,761 +Certainly 20 so, we pretty much know almost exactly where + +588 +00:29:23,763 --> 00:29:27,297 +you are. And then last one is cell tower triangulation. So + +589 +00:29:27,299 --> 00:29:30,134 +same way with the WiFi nodes it can look around to the cell + +590 +00:29:30,136 --> 00:29:33,403 +towers. Now there's fewer cell towers than there are WiFi + +591 +00:29:33,405 --> 00:29:36,073 +nodes okay, and they tend to be farther away from you. + +592 +00:29:36,075 --> 00:29:39,843 +Okay, so triangulating them is a little more iffy okay. + +593 +00:29:39,845 --> 00:29:41,211 +And sometimes there's not one for + +594 +00:29:41,213 --> 00:29:44,748 +very very far distance from you, a kilometer or more. So + +595 +00:29:44,750 --> 00:29:47,417 +that's why you start getting these really low accuracies + +596 +00:29:47,419 --> 00:29:51,355 +out here but the cellular radio is incredibly low power. + +597 +00:29:51,357 --> 00:29:53,323 +Super super low power, okay. And + +598 +00:29:53,325 --> 00:29:56,460 +your cellular radio is also automatically being turned on + +599 +00:29:56,462 --> 00:29:58,896 +and off and used as, you know you walk around and + +600 +00:29:58,898 --> 00:30:01,565 +you're making phone calls, or receiving phone calls etc. So + +601 +00:30:01,567 --> 00:30:03,934 +the cellular infrastructure's very low power but + +602 +00:30:03,936 --> 00:30:08,939 +low accuracy. Okay? Got all of that? All right + +603 +00:30:08,941 --> 00:30:10,974 +there's other things you can find out in the core location, + +604 +00:30:10,976 --> 00:30:13,377 +your speed, your course, that timestamp. + +605 +00:30:13,379 --> 00:30:16,113 +The reason the time stamp is important is that there + +606 +00:30:16,115 --> 00:30:18,115 +are a lot of ways to ask the system to give you + +607 +00:30:18,117 --> 00:30:21,051 +CLLocations, not in real time. In other words it's not going + +608 +00:30:21,053 --> 00:30:23,554 +to give you the location right now. Like you might be going + +609 +00:30:23,556 --> 00:30:25,789 +out for a run and you put your phone in your pocket and + +610 +00:30:25,791 --> 00:30:28,559 +it goes to sleep it can still collect locations. And + +611 +00:30:28,561 --> 00:30:31,562 +then when it wake back up it will send them all to you. And + +612 +00:30:31,564 --> 00:30:33,997 +when it does you're going to want to know the timestamps so + +613 +00:30:33,999 --> 00:30:35,065 +you knew where you were at the time. + +614 +00:30:35,067 --> 00:30:39,002 +So time stamp is an important part of the CLLocation. + +615 +00:30:39,004 --> 00:30:42,339 +All right. So how do we get a CLLocation? Well, you get it + +616 +00:30:42,341 --> 00:30:45,676 +from a CLLocationManager usually. Just like we had + +617 +00:30:45,678 --> 00:30:47,611 +a core motion, we have the CM motion manager. Well, + +618 +00:30:47,613 --> 00:30:51,381 +in the core location, we have the CLLocationManager. And + +619 +00:30:51,383 --> 00:30:53,917 +it has a delegate that's going to generally give you, + +620 +00:30:53,919 --> 00:30:57,387 +locations. What's really cool about it is you can actually + +621 +00:30:57,389 --> 00:31:00,490 +test in the simulator by simulating yourself being in + +622 +00:31:00,492 --> 00:31:03,227 +different locations. If you go down near the debugger bar, + +623 +00:31:03,229 --> 00:31:06,830 +there's a little guy there and that you can even upload + +624 +00:31:06,832 --> 00:31:09,333 +with the GPX file. The GPX file is just + +625 +00:31:09,335 --> 00:31:11,235 +a file with a bunch of waypoints in it, okay. + +626 +00:31:11,237 --> 00:31:14,438 +GPS locations can have other stuff in there like actually + +627 +00:31:14,440 --> 00:31:17,875 +URLs for photos taken at the location, stuff like that. But + +628 +00:31:17,877 --> 00:31:20,510 +it can have these location you can upload it and + +629 +00:31:20,512 --> 00:31:25,782 +have whatever testing you want in here okay. So + +630 +00:31:25,784 --> 00:31:26,250 +the CLLocationManager. + +631 +00:31:26,252 --> 00:31:29,086 +How do you use it? Similar to the CMMotion manager. First + +632 +00:31:29,088 --> 00:31:31,722 +you're going to check like to see what hardware's available. + +633 +00:31:31,724 --> 00:31:34,858 +Okay and then you're going to create a CLLocationManager and + +634 +00:31:34,860 --> 00:31:37,628 +set as delegate so that you can receive updates. + +635 +00:31:37,630 --> 00:31:41,198 +Then you're going to configure the manager to say what kind + +636 +00:31:41,200 --> 00:31:43,934 +of location you want. And we'll talk about what that + +637 +00:31:43,936 --> 00:31:45,836 +means and then you're going to start it going. + +638 +00:31:45,838 --> 00:31:49,006 +And once you start it going it's going to start sending + +639 +00:31:49,008 --> 00:31:52,042 +your locations based on how you, what you asked for, + +640 +00:31:52,044 --> 00:31:55,112 +all right. How, what kind of location monitoring is + +641 +00:31:55,114 --> 00:31:58,515 +available in the system? Well one is accuracy based + +642 +00:31:58,517 --> 00:32:02,452 +continual updates. This is what you would normally think. + +643 +00:32:02,454 --> 00:32:04,988 +You set an accuracy that you want. Okay, I want + +644 +00:32:04,990 --> 00:32:08,525 +highly accurate best for navigation or low accuracy and + +645 +00:32:08,527 --> 00:32:11,395 +the system will start sending you locations based on that + +646 +00:32:11,397 --> 00:32:13,630 +accuracy. So if you ask for best for navigation it's + +647 +00:32:13,632 --> 00:32:15,265 +gonna be sending you locations all the time and + +648 +00:32:15,267 --> 00:32:17,701 +they're gonna be highly accurate. If you ask for + +649 +00:32:17,703 --> 00:32:19,569 +every three kilometers. You could walk for + +650 +00:32:19,571 --> 00:32:22,205 +20 minutes before it sends you another location because it + +651 +00:32:22,207 --> 00:32:25,742 +notices another cell tower and can figure out its location. + +652 +00:32:25,744 --> 00:32:30,480 +Okay? So that's one way to do it. Another way is you can + +653 +00:32:30,482 --> 00:32:34,084 +get notified only when a significant location change + +654 +00:32:34,086 --> 00:32:37,321 +happens, okay. This is basically, I'm not talking + +655 +00:32:37,323 --> 00:32:40,190 +about how it's implemented here but I kinda am. + +656 +00:32:40,192 --> 00:32:44,594 +But it's basically when it sees a new cell tower. Okay. + +657 +00:32:44,596 --> 00:32:47,931 +So that's a significant enough change that it'll probably + +658 +00:32:47,933 --> 00:32:48,098 +send you one. So + +659 +00:32:48,100 --> 00:32:54,237 +this is not highly accurate locations necessarily. Okay. + +660 +00:32:54,239 --> 00:32:57,441 +The other one is region based updates so you can define + +661 +00:32:57,443 --> 00:33:01,979 +these regions either little circular areas in the world or + +662 +00:33:01,981 --> 00:33:06,083 +even where beacons live. Okay? Little bluetooth beacons and + +663 +00:33:06,085 --> 00:33:09,252 +you can get notified when you get close to that beacon or + +664 +00:33:09,254 --> 00:33:10,387 +you get real close to the beacon or + +665 +00:33:10,389 --> 00:33:14,157 +when you walk inside the circular area. Okay? And + +666 +00:33:14,159 --> 00:33:16,360 +then you also can have your heading monitored if + +667 +00:33:16,362 --> 00:33:20,497 +you change direction, it can send you a new location. + +668 +00:33:20,799 --> 00:33:23,133 +All right, so let's talk about how we use CLO, + +669 +00:33:23,135 --> 00:33:26,036 +CL location manager, and then we'll talk about how to make + +670 +00:33:26,038 --> 00:33:28,672 +each of those things work. First we want to find out what + +671 +00:33:28,674 --> 00:33:32,376 +our, hardware can do. One of the most important things + +672 +00:33:32,378 --> 00:33:35,846 +to find out about hardware is whether you're authorized to + +673 +00:33:35,848 --> 00:33:38,982 +get the user's location. As you can imagine, users might + +674 +00:33:38,984 --> 00:33:41,518 +not want you to know where they are, tracking their every + +675 +00:33:41,520 --> 00:33:45,188 +move out there. It's kind of a sensitive subject, okay. So + +676 +00:33:45,190 --> 00:33:48,658 +you have to make sure you're authorized to receive it. + +677 +00:33:48,660 --> 00:33:52,029 +And you can do this with these various things I'll talk about + +678 +00:33:52,031 --> 00:33:52,129 +authorization, on the next page. By the way, anytime you + +679 +00:33:52,131 --> 00:33:54,831 +in detail, + +680 +00:33:54,833 --> 00:33:57,234 +have an authorization status of any kind, not just for + +681 +00:33:57,236 --> 00:34:00,737 +location, you notice there's the states Authorized, Denied, + +682 +00:34:00,739 --> 00:34:04,641 +or Restricted. What Restricted means right there is, + +683 +00:34:04,643 --> 00:34:08,045 +it's denied, and the user can't change it. + +684 +00:34:08,047 --> 00:34:11,615 +So don't put up an alert that says, you, I'm not authorized + +685 +00:34:11,617 --> 00:34:14,918 +to get your location. Please go to Settings and change it. + +686 +00:34:14,920 --> 00:34:16,820 +Okay because they're not allowed to. There are ways + +687 +00:34:16,822 --> 00:34:19,723 +in enterprises inside companies where companies can + +688 +00:34:19,725 --> 00:34:23,193 +configure the phones of their employees. So for example, + +689 +00:34:23,195 --> 00:34:26,396 +they can't do this location service or other services. + +690 +00:34:26,398 --> 00:34:28,331 +Okay so be careful about the restricted state. + +691 +00:34:28,333 --> 00:34:32,102 +It's restricted just accept the fact you can't do it. + +692 +00:34:32,104 --> 00:34:35,272 +All right. And then you can also check for certain + +693 +00:34:35,274 --> 00:34:38,308 +kinds of monitoring like can you monitor for beacons or + +694 +00:34:38,310 --> 00:34:41,778 +can you monitor for circular regions? Most new hardware can + +695 +00:34:41,780 --> 00:34:44,548 +do all of these stuff or if you have an older phone maybe + +696 +00:34:44,550 --> 00:34:47,617 +it doesn't have the same capabilities to do that. + +697 +00:34:47,619 --> 00:34:50,387 +Alright? So let's talk about + +698 +00:34:50,389 --> 00:34:52,255 +this authorization piece though because it is + +699 +00:34:52,257 --> 00:34:54,458 +very important interesting piece to do it. + +700 +00:34:54,460 --> 00:34:57,160 +There's couple of steps you have to do to make it work. + +701 +00:34:57,162 --> 00:35:00,797 +One is you have to request authorization, okay. + +702 +00:35:00,799 --> 00:35:03,400 +This is ASynchronous, okay. You send this to the CL + +703 +00:35:03,402 --> 00:35:06,336 +location manager and you're gonna request one of + +704 +00:35:06,338 --> 00:35:08,371 +these two different kinds of authorizations. + +705 +00:35:08,373 --> 00:35:11,842 +In Use Authorization or Always Authorization. So + +706 +00:35:11,844 --> 00:35:14,578 +InUseAuthorization means you only wanna be allowed to + +707 +00:35:14,580 --> 00:35:18,148 +get the location when it's the foreground app the user is + +708 +00:35:18,150 --> 00:35:20,784 +using. Okay? When the user is in the background or + +709 +00:35:20,786 --> 00:35:22,652 +anything else, you can't find this location. + +710 +00:35:22,654 --> 00:35:24,287 +Users are fairly comfortable with that level + +711 +00:35:24,289 --> 00:35:26,756 +of authorization cuz they know when you're getting their, + +712 +00:35:26,758 --> 00:35:29,860 +their location. AlwaysAuthorization is you can + +713 +00:35:29,862 --> 00:35:32,429 +get their location anytime even the background and + +714 +00:35:32,431 --> 00:35:35,999 +that's very invasive of their privacy. So + +715 +00:35:36,001 --> 00:35:39,736 +you know a lot of people, users won't do this. + +716 +00:35:39,738 --> 00:35:42,672 +They won't give you that authorization, okay? So + +717 +00:35:42,674 --> 00:35:45,809 +the system might be putting up an alert asking the user if + +718 +00:35:45,811 --> 00:35:48,912 +it's okay, they're checking in their settings to see what + +719 +00:35:48,914 --> 00:35:51,781 +settings are there, things like that to find so + +720 +00:35:51,783 --> 00:35:54,651 +that's what its asynchronous. Eventually a delegate method + +721 +00:35:54,653 --> 00:35:56,520 +will be called in your CL location saying, + +722 +00:35:56,522 --> 00:35:58,054 +okay, here's your authorization task. + +723 +00:35:58,056 --> 00:36:01,925 +It was denied or it was accept, it was allowed. Okay? + +724 +00:36:01,927 --> 00:36:05,729 +Now, when you go off to request this authorization, + +725 +00:36:05,731 --> 00:36:09,766 +you have to have the user in their setting, + +726 +00:36:09,768 --> 00:36:10,433 +if they go into settings and + +727 +00:36:10,435 --> 00:36:13,370 +look at location services, your app will be there, + +728 +00:36:13,372 --> 00:36:15,739 +there has to be a switch they can click that says, + +729 +00:36:15,741 --> 00:36:20,644 +yes I'll allow my, this app to have always authorization or + +730 +00:36:20,646 --> 00:36:25,448 +in use authorization. To put that UI in the settings, + +731 +00:36:25,450 --> 00:36:28,752 +you have to put something in your info P list. Okay? + +732 +00:36:28,754 --> 00:36:31,388 +Which is this key right here NSLocation when + +733 +00:36:31,390 --> 00:36:32,789 +in use description or + +734 +00:36:32,791 --> 00:36:35,492 +NSLocation always use a description. This is a string + +735 +00:36:35,494 --> 00:36:41,231 +explaining why you want this particular authorization. + +736 +00:36:41,233 --> 00:36:45,235 +And if this key exists then, in settings, + +737 +00:36:45,237 --> 00:36:47,837 +the user will be able to have a switch to turn this on or + +738 +00:36:47,839 --> 00:36:51,007 +off. So if you don't put these in here, these things on top, + +739 +00:36:51,009 --> 00:36:54,344 +these funcs will always fail. Because there's no way for + +740 +00:36:54,346 --> 00:36:56,479 +the user to set that in their settings, so + +741 +00:36:56,481 --> 00:36:58,882 +they'll all just always fail. Okay? And + +742 +00:36:58,884 --> 00:37:02,118 +the system can't put up an alert even asking if it's okay + +743 +00:37:02,120 --> 00:37:03,920 +because if they said yes there's no way, + +744 +00:37:03,922 --> 00:37:06,189 +there's no switch for the system to turn on. + +745 +00:37:06,191 --> 00:37:07,891 +So you'd just be always denied, so + +746 +00:37:07,893 --> 00:37:13,296 +you need these two steps to get authorization. All right. + +747 +00:37:13,298 --> 00:37:17,167 +Now, how do you then get the CL location from the location + +748 +00:37:17,169 --> 00:37:19,002 +manager? Of course you can pull, but + +749 +00:37:19,004 --> 00:37:21,705 +like with motion manager we say that's not a good idea. + +750 +00:37:21,707 --> 00:37:24,341 +But what you can do you can just ask the location manager + +751 +00:37:24,343 --> 00:37:25,075 +please give me the current location. And + +752 +00:37:25,077 --> 00:37:28,178 +it will give you the location with whatever accuracy it has. + +753 +00:37:28,180 --> 00:37:31,648 +Okay but really the way we do it is we set this var + +754 +00:37:31,650 --> 00:37:34,384 +in the location manager called desired accuracy. + +755 +00:37:34,386 --> 00:37:36,620 +That's one of those accuracies like best for navigation and + +756 +00:37:36,622 --> 00:37:39,723 +all those things. And then also a distance filter which + +757 +00:37:39,725 --> 00:37:43,360 +is how far the user has to move before we're gonna give + +758 +00:37:43,362 --> 00:37:46,863 +a new location. Okay? So, if you take ten meters, + +759 +00:37:46,865 --> 00:37:50,033 +you just gotta walk ten meters down the way before another + +760 +00:37:50,035 --> 00:37:50,867 +location will come. And + +761 +00:37:50,869 --> 00:37:53,970 +those two things together will give the system a good idea of + +762 +00:37:53,972 --> 00:37:57,807 +how hard it has to work to get the users location. Okay. So + +763 +00:37:57,809 --> 00:38:01,611 +you set those and then you say start updating the location. + +764 +00:38:01,613 --> 00:38:04,481 +And as soon as you say start updating location, as long as + +765 +00:38:04,483 --> 00:38:07,250 +you've set these, you're going to start getting locations + +766 +00:38:07,252 --> 00:38:11,588 +appropriate to these settings up here. Now, be sure, + +767 +00:38:11,590 --> 00:38:12,455 +just like with the motion manager, + +768 +00:38:12,457 --> 00:38:14,924 +in fact even more importantly than the motion manager, + +769 +00:38:14,926 --> 00:38:17,627 +to stop them when you're not gonna do anything with + +770 +00:38:17,629 --> 00:38:20,430 +the results. If locations are coming, and you're ignoring + +771 +00:38:20,432 --> 00:38:23,967 +them, you should have stopped it because this is basically + +772 +00:38:23,969 --> 00:38:26,102 +turn on battery save. [LAUGH] Okay. If you turn, turn, + +773 +00:38:26,104 --> 00:38:29,072 +if you don't stop updating location and + +774 +00:38:29,074 --> 00:38:31,141 +you're not using it, you're just draining your battery for + +775 +00:38:31,143 --> 00:38:33,043 +nothing, it's probably the number one way to drain + +776 +00:38:33,045 --> 00:38:37,480 +their battery, actually. Okay. And you people will rapidly, + +777 +00:38:37,482 --> 00:38:40,550 +you'll get it on your app store thing on the comments + +778 +00:38:40,552 --> 00:38:42,886 +it'll say drained your battery don't buy this thing. + +779 +00:38:42,888 --> 00:38:46,890 +Okay? So you want to be really careful not to do that. Okay. + +780 +00:38:46,892 --> 00:38:50,160 +So once you turn it on you're gonna start getting this + +781 +00:38:50,162 --> 00:38:54,698 +delegate method sent to you. Did update locations is plural + +782 +00:38:54,700 --> 00:38:56,333 +which in a, within array of locations. + +783 +00:38:56,335 --> 00:38:58,535 +Now, why is that an array of locations instead of + +784 +00:38:58,537 --> 00:39:00,170 +just sending you each location one by one. + +785 +00:39:00,172 --> 00:39:03,073 +Well, it's that running example, you got for a run, + +786 +00:39:03,075 --> 00:39:06,343 +your phone goes to sleep, it collects a bunch of locations + +787 +00:39:06,345 --> 00:39:09,312 +and I'm not gonna talk about how you'd set that up but + +788 +00:39:09,314 --> 00:39:11,781 +you can look in the documentation. And when you're + +789 +00:39:11,783 --> 00:39:14,317 +pick your phone up and then and say, how was my run. Boom! + +790 +00:39:14,319 --> 00:39:16,619 +You're gonna get all these locations as an array here. + +791 +00:39:16,621 --> 00:39:19,289 +Okay, with time stamps and all that, so you'll be able to + +792 +00:39:19,291 --> 00:39:23,727 +reconstruct the run. Okay, similar APIs this, for + +793 +00:39:23,729 --> 00:39:27,797 +heading, if you wanna just monitor the user's heading. + +794 +00:39:28,333 --> 00:39:29,799 +Error reporting is important and + +795 +00:39:29,801 --> 00:39:32,669 +easy to miss because you have to implement another delegate + +796 +00:39:32,671 --> 00:39:35,171 +method here, which is locationManagerDidFailWithEr- + +797 +00:39:35,173 --> 00:39:38,908 +ror. But you definitely do want to be looking at this. + +798 +00:39:38,910 --> 00:39:39,142 +Okay if you have, + +799 +00:39:39,144 --> 00:39:41,478 +if you are using a location you have to implement this. + +800 +00:39:41,480 --> 00:39:45,148 +Because for example the user could at any time go to their + +801 +00:39:45,150 --> 00:39:45,215 +say no I don't want this guy using my location. + +802 +00:39:45,217 --> 00:39:46,916 +settings and + +803 +00:39:46,918 --> 00:39:50,420 +In which case you're gonna start getting this denied. + +804 +00:39:50,422 --> 00:39:53,289 +And if you don't look for this, your output's just gonna + +805 +00:39:53,291 --> 00:39:55,792 +go into some wacky state because it's not gonna know + +806 +00:39:55,794 --> 00:39:57,861 +what's happening. Okay you need to what's happening. + +807 +00:39:57,863 --> 00:40:01,598 +Also, error location unknown. If from some reason, it, + +808 +00:40:01,600 --> 00:40:04,300 +we can't find the location. Maybe you asked for best for + +809 +00:40:04,302 --> 00:40:07,404 +navigation, it just can't find any, thing to give you your + +810 +00:40:07,406 --> 00:40:10,273 +location, so you wanna know that as well, okay? + +811 +00:40:10,275 --> 00:40:11,808 +So definitely wanna look at this thing. + +812 +00:40:11,810 --> 00:40:14,978 +If you're doing location manager in your final project, + +813 +00:40:14,980 --> 00:40:19,482 +you got to implement this, okay? All right, + +814 +00:40:19,484 --> 00:40:21,718 +lets talk about getting your location in the background, + +815 +00:40:21,720 --> 00:40:24,487 +verses about getting your location in the foreground. + +816 +00:40:24,489 --> 00:40:26,723 +Okay, so when you get in the foreground it's all + +817 +00:40:26,725 --> 00:40:29,225 +the things we just talked about. + +818 +00:40:29,227 --> 00:40:31,628 +There's a bird in here with it. + +819 +00:40:31,630 --> 00:40:32,929 +When you're in the background, though, + +820 +00:40:32,931 --> 00:40:34,764 +things are a little different because you know that + +821 +00:40:34,766 --> 00:40:36,800 +generally you're not allowed to run in the background. + +822 +00:40:36,802 --> 00:40:40,170 +You kind of go quiet, and then you get in those cycles. But + +823 +00:40:40,172 --> 00:40:42,439 +there are ways you, you remember when we went and + +824 +00:40:42,441 --> 00:40:45,408 +enabled iCloud in that capabilities thing? Well, + +825 +00:40:45,410 --> 00:40:48,478 +there's things in there where you can enable backgrounding + +826 +00:40:48,480 --> 00:40:52,015 +for locations, okay? Now if you do this + +827 +00:40:52,017 --> 00:40:53,883 +you will continue to get stuff in the background. + +828 +00:40:53,885 --> 00:40:56,653 +You can imagine it's even more important to be sure you're + +829 +00:40:56,655 --> 00:40:58,188 +not sucking the battery at this, + +830 +00:40:58,190 --> 00:41:01,090 +in this situation, okay? And this is the kind of thing, + +831 +00:41:01,092 --> 00:41:03,326 +if you're sucking the battery in the background there, + +832 +00:41:03,328 --> 00:41:06,162 +your App Store app might not get approved, okay? + +833 +00:41:06,164 --> 00:41:07,764 +That's how important it is not to be sitting there + +834 +00:41:07,766 --> 00:41:10,633 +sucking the battery in the background, okay? Now, + +835 +00:41:10,635 --> 00:41:14,304 +there are other ways though, very battery-efficient ways, + +836 +00:41:14,306 --> 00:41:15,738 +to get your location in the background, so + +837 +00:41:15,740 --> 00:41:19,476 +let's talk about those. One is that significant monitoring I + +838 +00:41:19,478 --> 00:41:22,779 +thing I was telling you about where you're walking around, + +839 +00:41:22,781 --> 00:41:24,814 +and it notices a new cell tower so + +840 +00:41:24,816 --> 00:41:27,183 +it's very kind of large grained. + +841 +00:41:27,185 --> 00:41:29,953 +That's an awesome way to get locations for + +842 +00:41:29,955 --> 00:41:33,289 +very low battery, uses almost no battery to do this. And + +843 +00:41:33,291 --> 00:41:35,959 +what's more and really cool about it, if you're app is in + +844 +00:41:35,961 --> 00:41:39,662 +the background. You'll get the notification if it's not even + +845 +00:41:39,664 --> 00:41:44,234 +running, it will get launched and told this information. So + +846 +00:41:44,236 --> 00:41:49,472 +this a very powerful telling you where the location is. + +847 +00:41:49,474 --> 00:41:51,074 +And when it gets launched, by the way, if, + +848 +00:41:51,076 --> 00:41:53,776 +if they're using some other app, it will launch it and + +849 +00:41:53,778 --> 00:41:54,844 +launch you in the background. + +850 +00:41:54,846 --> 00:41:56,513 +So you can figure out where you are and + +851 +00:41:56,515 --> 00:41:57,747 +decide if you need to do something. + +852 +00:41:57,749 --> 00:42:00,416 +Okay, so this one is really cool, really low power, + +853 +00:42:00,418 --> 00:42:03,520 +the only problem with it, it's large grained. Now, + +854 +00:42:03,522 --> 00:42:06,823 +once you get woken up, that you've significantly changed, + +855 +00:42:06,825 --> 00:42:10,793 +you could start doing more close location, KGPS location, + +856 +00:42:10,795 --> 00:42:12,662 +try and find out a little bit exactly where you are, + +857 +00:42:12,664 --> 00:42:16,666 +if you want. Although be careful not to take too long, + +858 +00:42:16,668 --> 00:42:17,133 +when you get launched for + +859 +00:42:17,135 --> 00:42:19,802 +this in the background because the system will stop doing + +860 +00:42:19,804 --> 00:42:24,674 +this. If you, you know starts consuming a lot of resources + +861 +00:42:24,676 --> 00:42:29,779 +in the background there, okay? So be careful with that. + +862 +00:42:29,781 --> 00:42:32,615 +Similarly is the region base monitoring, okay? + +863 +00:42:32,617 --> 00:42:34,551 +Where you specify a circle or beacons, + +864 +00:42:34,553 --> 00:42:38,254 +okay? That also will wake you up and even launch your + +865 +00:42:38,256 --> 00:42:41,991 +application if it notices you going into that region. Okay, + +866 +00:42:41,993 --> 00:42:45,862 +and run you in the background. Also low power, you know, + +867 +00:42:45,864 --> 00:42:48,798 +really nice way to do it. So if that will meet your needs + +868 +00:42:48,800 --> 00:42:52,535 +as well, that's a good one to do, okay. + +869 +00:42:52,537 --> 00:42:56,039 +When you enter a region, either beacon or + +870 +00:42:56,041 --> 00:42:59,576 +circular region, you're gonna get these delegate methods. + +871 +00:42:59,578 --> 00:43:01,244 +didEnterRegion, didExitRegion, and + +872 +00:43:01,246 --> 00:43:05,114 +monitoringDidFailForRegion. Also here's the error handler + +873 +00:43:05,116 --> 00:43:09,118 +for that one, okay? So that's kind of a fun one. + +874 +00:43:09,120 --> 00:43:12,355 +Region-monitoring works when you're not running because all + +875 +00:43:12,357 --> 00:43:15,592 +your regions are named, okay? They all have to have unique + +876 +00:43:15,594 --> 00:43:18,695 +names, and so when you get launched you'll know which one + +877 +00:43:18,697 --> 00:43:23,600 +fired by its name. You also, there is by the way a maximum + +878 +00:43:23,602 --> 00:43:26,269 +limit to the circular region called maximum region + +879 +00:43:26,271 --> 00:43:28,504 +monitoring distance, you want to look at that. + +880 +00:43:28,506 --> 00:43:30,940 +You can't say when I enter the United States, + +881 +00:43:30,942 --> 00:43:33,009 +okay that won't take that big of a region. + +882 +00:43:33,011 --> 00:43:36,546 +It has to be much much smaller,and this will tell you + +883 +00:43:36,548 --> 00:43:41,084 +how big it can be, okay? This is the beacon thing. + +884 +00:43:41,086 --> 00:43:42,518 +When you're looking for beacons, + +885 +00:43:42,520 --> 00:43:45,288 +what you're really interested in is how far from the beacon + +886 +00:43:45,290 --> 00:43:48,858 +am I? Okay, am I close to it, like really, really next to + +887 +00:43:48,860 --> 00:43:51,294 +it? Or a little bit far away or across the ways. So + +888 +00:43:51,296 --> 00:43:54,364 +beacons are used for things like, you're going to a coffee + +889 +00:43:54,366 --> 00:43:56,599 +shop and when you get right up to the register. + +890 +00:43:56,601 --> 00:43:58,701 +Maybe it offers you a coupon or something like that, + +891 +00:43:58,703 --> 00:44:00,803 +well it needs to know you're right near the register. + +892 +00:44:00,805 --> 00:44:03,773 +But maybe when you just walk in the store it just gives you + +893 +00:44:03,775 --> 00:44:07,010 +an advertisement or directs you to some display, okay? + +894 +00:44:07,012 --> 00:44:09,679 +So the beacon would be sitting maybe near the register and + +895 +00:44:09,681 --> 00:44:12,515 +so this thing is telling you. That's why we call it ranging, + +896 +00:44:12,517 --> 00:44:15,652 +start ranging these beacons. Now these beacons could be + +897 +00:44:15,654 --> 00:44:19,055 +other iOS devices, could serve as a beacon, okay? Or + +898 +00:44:19,057 --> 00:44:23,159 +you could even buy these third party stand alone eye beacons + +899 +00:44:23,161 --> 00:44:26,963 +basically that will act as beacons. If you wanted to be + +900 +00:44:26,965 --> 00:44:30,033 +a beacon, okay, that's beyond the scope of this class. + +901 +00:44:30,035 --> 00:44:32,135 +I can't really tell you how to do that, okay. + +902 +00:44:32,137 --> 00:44:35,471 +You need to get the Core Bluetooth Framework involved + +903 +00:44:35,473 --> 00:44:37,940 +here and check out CBPeripheralManager. + +904 +00:44:37,942 --> 00:44:41,344 +It will show you how to do it but it's a little more + +905 +00:44:41,346 --> 00:44:44,747 +complicated than I can show in a couple slides so. + +906 +00:44:44,749 --> 00:44:48,084 +So that's it for core location. Let's now talk about + +907 +00:44:48,086 --> 00:44:50,687 +Map Kit which is the UI way of showing location. + +908 +00:44:50,689 --> 00:44:55,191 +MKMapView is a UI view that displays a map, okay? + +909 +00:44:55,193 --> 00:44:59,862 +Looks just like the maps app, on iOS. + +910 +00:44:59,864 --> 00:45:03,533 +A map can have annotations, like this little red pin + +911 +00:45:03,535 --> 00:45:07,570 +down there, okay? Each annotation has a coordinate, + +912 +00:45:07,572 --> 00:45:11,140 +obviously the GPS location where that thing is, and also + +913 +00:45:11,142 --> 00:45:15,545 +a title. And a subtitle, okay, there's no subtitle shown + +914 +00:45:15,547 --> 00:45:16,412 +in this one right here, + +915 +00:45:16,414 --> 00:45:21,451 +okay? The annotations though can also have this call out, + +916 +00:45:21,453 --> 00:45:24,587 +this white area. That's not part of the annotation view, + +917 +00:45:24,589 --> 00:45:29,625 +that's a call out that the annotation view brings up. So + +918 +00:45:29,627 --> 00:45:32,595 +we're going to talk about the components of this callout + +919 +00:45:32,597 --> 00:45:35,431 +in a second as well. Actually it's talking right now. + +920 +00:45:35,433 --> 00:45:38,301 +[COUGH] It's got a left accessory view and + +921 +00:45:38,303 --> 00:45:39,335 +a right accessory view. + +922 +00:45:39,337 --> 00:45:42,505 +And these are usually things like UI image views or + +923 +00:45:42,507 --> 00:45:46,843 +maybe UI buttons things like that, okay. So this is how + +924 +00:45:46,845 --> 00:45:51,047 +we're going to build our map UIs out of these components. + +925 +00:45:51,049 --> 00:45:52,281 +So how do you create with MapView? + +926 +00:45:52,283 --> 00:45:55,852 +Really easy. MKMapView or MKMapView with a frame, + +927 +00:45:55,854 --> 00:45:59,388 +initializer, or you can drag it out in your storyboard, + +928 +00:45:59,390 --> 00:46:02,759 +which is what we'll do in the demo. And MapView, what + +929 +00:46:02,761 --> 00:46:06,129 +does it, how does it basically work? It's got an array, + +930 +00:46:06,131 --> 00:46:09,932 +this var annotations which is an array of MKAnnotation, + +931 +00:46:09,934 --> 00:46:15,271 +okay. MKAnnotation is not a class, it's a protocol. So + +932 +00:46:15,273 --> 00:46:18,074 +anything could be an annotation on a map as long as + +933 +00:46:18,076 --> 00:46:21,577 +it implements this protocol. What is that protocol? + +934 +00:46:21,579 --> 00:46:26,048 +It has coordinate, title, and subtitle, + +935 +00:46:26,050 --> 00:46:29,085 +okay? If you implement those three bars, boom, + +936 +00:46:29,087 --> 00:46:32,655 +you can be thrown onto a map. You will be an MKAnnotation. + +937 +00:46:32,657 --> 00:46:36,626 +They're all get, see? Var title is an optional string by + +938 +00:46:36,628 --> 00:46:38,528 +the way but it's really expected to be implemented. + +939 +00:46:38,530 --> 00:46:41,998 +Don't ever leave this nil or system does not like that, + +940 +00:46:42,000 --> 00:46:45,201 +okay? I'm not sure why, it's optional, should be and then + +941 +00:46:45,203 --> 00:46:47,937 +the core location coordination coordinate remember that's + +942 +00:46:47,939 --> 00:46:53,643 +cllocation coordinate 2D, latitude and longitude Ok, + +943 +00:46:53,645 --> 00:46:56,445 +so that's it. So it's got this array of annotations but + +944 +00:46:56,447 --> 00:47:00,550 +you notice this array is read only. So to add annotations or + +945 +00:47:00,552 --> 00:47:03,719 +remove annotations you have to use these methods, add or + +946 +00:47:03,721 --> 00:47:05,087 +remove annotations. + +947 +00:47:06,825 --> 00:47:08,991 +It's generally a good idea from a performance perspective + +948 +00:47:08,993 --> 00:47:13,229 +to add all of your annotations that you know about up front. + +949 +00:47:13,231 --> 00:47:14,564 +And that's because the annotation views, + +950 +00:47:14,566 --> 00:47:19,101 +those little pins. Get reused just like in a table view, + +951 +00:47:19,103 --> 00:47:21,671 +okay? So you might as well add them all upfront and + +952 +00:47:21,673 --> 00:47:24,974 +let the system reuse the pins as you scroll, + +953 +00:47:24,976 --> 00:47:30,246 +scroll around the world. Okay, can reuse them. What do + +954 +00:47:30,248 --> 00:47:32,782 +annotations look like on the map? Well we saw it before, + +955 +00:47:32,784 --> 00:47:37,453 +right? If you use an MKPinAnnotationView, which is + +956 +00:47:37,455 --> 00:47:40,890 +a subclass of MKAnnotationView you get a little pin. + +957 +00:47:40,892 --> 00:47:44,126 +It can be red or purple I think or maybe another + +958 +00:47:44,128 --> 00:47:47,063 +color. But it does allow you to even change this image. If + +959 +00:47:47,065 --> 00:47:49,599 +you don't like a pin, you can change it to something else. + +960 +00:47:49,601 --> 00:47:51,934 +And when you click on the PinAnnotationView, + +961 +00:47:51,936 --> 00:47:52,568 +you get this call out. And + +962 +00:47:52,570 --> 00:47:56,973 +that's what the call out looks like, okay? So what happens + +963 +00:47:56,975 --> 00:48:00,509 +when you press the pin besides this call-out coming out? And + +964 +00:48:00,511 --> 00:48:05,214 +by the way, this call-out only comes out if canShowCallout is + +965 +00:48:05,216 --> 00:48:08,551 +true on the MK annotation pin annotation view. + +966 +00:48:08,553 --> 00:48:11,520 +So you have to have that be true. So this will come up, + +967 +00:48:11,522 --> 00:48:14,690 +but in addition to this appearing, a delegate method + +968 +00:48:14,692 --> 00:48:17,994 +will be sent to the map views delegate. It's called + +969 +00:48:17,996 --> 00:48:22,999 +Map view did select annotation view, okay? And so this + +970 +00:48:23,001 --> 00:48:25,601 +is important little method right here because if you're + +971 +00:48:25,603 --> 00:48:30,039 +gonna show anything expensive in your call out, like so + +972 +00:48:30,041 --> 00:48:32,008 +you're gonna go over their network and grab an image or + +973 +00:48:32,010 --> 00:48:34,777 +something like that. You're gonna wanna wait to do it + +974 +00:48:34,779 --> 00:48:37,580 +until didSelectAnnotationView. Because if the user never + +975 +00:48:37,582 --> 00:48:40,549 +clicks on this pin, he's never gonna see that image. So you + +976 +00:48:40,551 --> 00:48:43,552 +don't wanna waste your time fetching it. Okay? So this + +977 +00:48:43,554 --> 00:48:45,821 +is a place where you're gonna do expensive stuff that's + +978 +00:48:45,823 --> 00:48:48,291 +gonna show in the call out. You also, though, + +979 +00:48:48,293 --> 00:48:51,027 +might segue out of this. When someone clicks on a pin, + +980 +00:48:51,029 --> 00:48:54,463 +maybe you wanna go segue to some other view, I don't know. + +981 +00:48:54,465 --> 00:48:58,868 +Okay, but this is the target action of MKAnnotations. + +982 +00:48:59,003 --> 00:49:01,671 +All right, so how are these AnnotationViews, these little + +983 +00:49:01,673 --> 00:49:04,440 +pins created and associated with those annotations? + +984 +00:49:04,442 --> 00:49:07,610 +Because we know MKMap View only has this array of + +985 +00:49:07,612 --> 00:49:11,347 +annotations. So how do those pins get there to show them? + +986 +00:49:11,349 --> 00:49:14,550 +And the answer is from this delegate method right here, + +987 +00:49:14,552 --> 00:49:15,651 +MapView, viewForAnnotation. + +988 +00:49:15,653 --> 00:49:18,888 +This is very much like self or roll in index path in table + +989 +00:49:18,890 --> 00:49:22,091 +view. Okay? So in there, you're creating a cell which + +990 +00:49:22,093 --> 00:49:25,361 +is a view. Okay, UI table view cell. Here you're creating + +991 +00:49:25,363 --> 00:49:28,864 +an MK annotation view like the Pin annotation view. Okay. So + +992 +00:49:28,866 --> 00:49:31,600 +let's go through this and see how we do it. First we're + +993 +00:49:31,602 --> 00:49:36,505 +gonna dq a reusable one using some identifier but + +994 +00:49:36,507 --> 00:49:40,876 +if that fail, okay and view is nil if we can't dq one + +995 +00:49:40,878 --> 00:49:44,914 +then there's no prototype like there is in the table view so + +996 +00:49:44,916 --> 00:49:47,717 +we have to create the prototype in code. So + +997 +00:49:47,719 --> 00:49:49,185 +here I'm creating the prototype by saying, + +998 +00:49:49,187 --> 00:49:52,955 +view equals MK pin Annotation view, okay? But I'm specifying + +999 +00:49:52,957 --> 00:49:56,559 +that sam reuse identifier that later I might come back and do + +1000 +00:49:56,561 --> 00:49:59,595 +this reuseable with, you see? So that's how they get done. + +1001 +00:49:59,597 --> 00:50:02,665 +And then can't show call out either set to true or false, + +1002 +00:50:02,667 --> 00:50:05,768 +whichever one you want. Okay. + +1003 +00:50:05,770 --> 00:50:07,570 +Then we're gonna whether we created the view or + +1004 +00:50:07,572 --> 00:50:10,206 +not, we're gonna wanna set the view's annotation to be + +1005 +00:50:10,208 --> 00:50:15,044 +the annotation we're creating, this view for. And then, + +1006 +00:50:15,046 --> 00:50:18,881 +we're gonna wanna prepare this view with anything else. + +1007 +00:50:18,883 --> 00:50:21,817 +Like if it's gonna have a left call out accessor view, + +1008 +00:50:21,819 --> 00:50:22,318 +which is an image view, + +1009 +00:50:22,320 --> 00:50:25,354 +this is the time we would add the image view. This might not + +1010 +00:50:25,356 --> 00:50:28,624 +be the time we actually go fetch the image to put there, + +1011 +00:50:28,626 --> 00:50:31,427 +you might wait until didSelectAnnotationView for + +1012 +00:50:31,429 --> 00:50:34,630 +you to do that but we're not gonna wanna put the UI image + +1013 +00:50:34,632 --> 00:50:37,867 +view in there so that it's ready to go in the call out. + +1014 +00:50:37,869 --> 00:50:41,537 +Okay, and then we're gonna return the view then + +1015 +00:50:41,539 --> 00:50:45,141 +the system gonna use this view to show that pin. + +1016 +00:50:45,143 --> 00:50:47,777 +Okay, interesting properties on UIAnnotationView, + +1017 +00:50:47,779 --> 00:50:49,078 +we already talked about the left and + +1018 +00:50:49,080 --> 00:50:51,514 +right CallOutAccessoryViews, which are just views. + +1019 +00:50:51,516 --> 00:50:55,317 +There's also whether it's enabled or not. This image is + +1020 +00:50:55,319 --> 00:50:58,087 +the image of the pin, not the image that's in the callout, + +1021 +00:50:58,089 --> 00:51:00,656 +it's the image of the pin. Also you can + +1022 +00:51:00,658 --> 00:51:03,359 +make it draggable, setting draggable to true. If you do + +1023 +00:51:03,361 --> 00:51:06,529 +that your MKAnnotations, the coordinate property would have + +1024 +00:51:06,531 --> 00:51:09,465 +to be get and set. Obviously if you're gonna drag it around + +1025 +00:51:09,467 --> 00:51:12,268 +you have to be able to set the property as well. + +1026 +00:51:12,870 --> 00:51:16,605 +Okay. This cool property or + +1027 +00:51:16,607 --> 00:51:19,642 +delegate method right here calloutAccessoryControlTapped + +1028 +00:51:19,644 --> 00:51:23,813 +will get sent to your map view delegates If your left or + +1029 +00:51:23,815 --> 00:51:27,049 +right call out accessory is a ui control. + +1030 +00:51:27,051 --> 00:51:29,852 +Basically a ui button okay? So if you put a button + +1031 +00:51:29,854 --> 00:51:32,455 +at your left or right call out accessory when it gets touched + +1032 +00:51:32,457 --> 00:51:36,459 +you're gonna get this call out accessory control tapped + +1033 +00:51:36,861 --> 00:51:39,695 +method which is pretty cool. + +1034 +00:51:39,697 --> 00:51:42,631 +In did select annotation view we talked about the fact + +1035 +00:51:42,633 --> 00:51:46,268 +that this is where you might want to create your image or + +1036 +00:51:46,270 --> 00:51:50,706 +even fire off a thread or q, on a different q, fire off + +1037 +00:51:50,708 --> 00:51:53,509 +a request to go get the image. When it comes back later + +1038 +00:51:53,511 --> 00:51:57,813 +you'll have to load it up into the accessory view. Okay? + +1039 +00:51:57,815 --> 00:51:59,982 +Just like when you're scrolling around in a table + +1040 +00:51:59,984 --> 00:52:02,685 +view, realize that if you're scrolling around on the map + +1041 +00:52:02,687 --> 00:52:06,455 +you might fire off a dispatch async here to go get this + +1042 +00:52:06,457 --> 00:52:09,758 +image, and when it comes back that image is no longer being + +1043 +00:52:09,760 --> 00:52:12,761 +displayed in this call accessory view because it gets + +1044 +00:52:12,763 --> 00:52:17,566 +reused, reused right by other ones. So be careful about + +1045 +00:52:17,568 --> 00:52:21,537 +that. The map you can configure the way it displays. + +1046 +00:52:21,539 --> 00:52:24,673 +This is a var on MKMapView. You can do standard, + +1047 +00:52:24,675 --> 00:52:27,710 +satellite, or hybrid. So standard is like streets and + +1048 +00:52:27,712 --> 00:52:31,447 +things like that, satellite is like Google Earth type thing. + +1049 +00:52:31,449 --> 00:52:35,251 +And then hybrid is a mix, an overlay of those two things. + +1050 +00:52:35,253 --> 00:52:39,155 +You can also show the user's current location. On the map + +1051 +00:52:39,157 --> 00:52:40,923 +just by saying this Bool to true and it will show it. + +1052 +00:52:40,925 --> 00:52:43,659 +I think the users current location is blue or maybe it's + +1053 +00:52:43,661 --> 00:52:46,128 +purple, I don't know. But it will just show in there. + +1054 +00:52:46,130 --> 00:52:48,864 +You can also get the users location as well. + +1055 +00:52:48,866 --> 00:52:51,500 +As MKUserLocation which is just thing that implements + +1056 +00:52:51,502 --> 00:52:56,472 +the MKAnnotation protocol. You can also restrict scrolling. + +1057 +00:52:56,474 --> 00:52:59,008 +Okay, maybe you don't want. The 3D mode. + +1058 +00:52:59,010 --> 00:53:01,544 +If you don't want 3D mode, set pitch enable to false and + +1059 +00:53:01,546 --> 00:53:06,248 +it won't pitch up to show you 3D maps. You can control + +1060 +00:53:06,250 --> 00:53:08,851 +the camera if you do allow 3D you can control + +1061 +00:53:08,853 --> 00:53:12,254 +where the camera is pointing using this, API right here, + +1062 +00:53:12,256 --> 00:53:16,025 +that's kind of fun. You can also say what part of + +1063 +00:53:16,027 --> 00:53:19,094 +the world is being shown with the MP coordinate region which + +1064 +00:53:19,096 --> 00:53:22,998 +is just a latitude longitude and a span okay which is + +1065 +00:53:23,000 --> 00:53:28,370 +number of meters. Okay? So it shows that will show that part + +1066 +00:53:28,372 --> 00:53:32,208 +of the Earth. Actually it's not it's not even meters. + +1067 +00:53:32,210 --> 00:53:35,044 +The span is a delta of latitude and longitude. + +1068 +00:53:35,046 --> 00:53:36,078 +How many degrees of latitude and + +1069 +00:53:36,080 --> 00:53:38,581 +how many degrees of longitude to show. + +1070 +00:53:39,217 --> 00:53:43,886 +Okay? What else we can do here? + +1071 +00:53:43,888 --> 00:53:46,722 +I just want you to note that there's a whole bunch of + +1072 +00:53:46,724 --> 00:53:49,892 +C-like functions, they're swift global functions, + +1073 +00:53:49,894 --> 00:53:52,494 +they're not methods, that you can do to convert + +1074 +00:53:52,496 --> 00:53:55,064 +like from map coordinates to view coordinates and + +1075 +00:53:55,066 --> 00:53:58,300 +things like that. So make sure you take a look at these and + +1076 +00:53:58,302 --> 00:54:01,270 +understand all of these. There's probably about 15 or + +1077 +00:54:01,272 --> 00:54:03,906 +20 of them that will help you do conversions. + +1078 +00:54:03,908 --> 00:54:08,110 +There's also some methods that will do it, as well, + +1079 +00:54:08,112 --> 00:54:13,415 +in MKMapView. There's a cool method in MKMapView called + +1080 +00:54:13,417 --> 00:54:15,618 +didChangeRegionAnimated. + +1081 +00:54:15,620 --> 00:54:18,087 +Okay? So, if you tell the mapview to + +1082 +00:54:18,089 --> 00:54:21,257 +show a different part of the world like New York, okay. + +1083 +00:54:21,259 --> 00:54:23,559 +It's going to animate going there. It's going to + +1084 +00:54:23,561 --> 00:54:26,695 +scroll over there. But if I'm in San Francisco and I say, + +1085 +00:54:26,697 --> 00:54:29,999 +show New York it's gonna go whoo, okay, you're not even + +1086 +00:54:30,001 --> 00:54:32,534 +gonna see it. Nebraska, you'll never see it okay. + +1087 +00:54:32,536 --> 00:54:35,337 +In Nebraska, you can go by so fast. You'll never see it. + +1088 +00:54:35,339 --> 00:54:36,905 +What would be really cool is if you said, + +1089 +00:54:36,907 --> 00:54:39,408 +I'm in San Francisco, show New York, first you said + +1090 +00:54:39,410 --> 00:54:42,678 +show the whole United States then show New York. + +1091 +00:54:42,680 --> 00:54:45,681 +Right then you get this cool animation. San Francisco to + +1092 +00:54:45,683 --> 00:54:47,249 +the whole United States down to New York. + +1093 +00:54:47,251 --> 00:54:49,318 +Wouldn't that be cool? Yes it would. And so + +1094 +00:54:49,320 --> 00:54:52,621 +the way you do that is you first of all set your location + +1095 +00:54:52,623 --> 00:54:53,489 +to the whole United States or + +1096 +00:54:53,491 --> 00:54:56,358 +middle of the United States with a large span and it will + +1097 +00:54:56,360 --> 00:54:59,695 +go up to there and as soon as the animation of that finishes + +1098 +00:54:59,697 --> 00:55:04,166 +you'll get sent this. Okay cuz it's a did change region. + +1099 +00:55:04,168 --> 00:55:04,533 +It finished the change region. + +1100 +00:55:04,535 --> 00:55:08,537 +As soon as it sends you this now you animate to New York. + +1101 +00:55:08,706 --> 00:55:10,005 +So essentially chaining you see. + +1102 +00:55:10,007 --> 00:55:11,907 +And now it will [INAUDIBLE] New York. So this is the way + +1103 +00:55:11,909 --> 00:55:14,276 +you can chain animations to make the animations kind of + +1104 +00:55:14,278 --> 00:55:18,480 +fly around the world nicely. MKLocalSearch I'm not going to + +1105 +00:55:18,482 --> 00:55:21,750 +really talk about it but it's a way that you can put normal + +1106 +00:55:21,752 --> 00:55:25,321 +English language descriptions of places like Ike's, and + +1107 +00:55:25,323 --> 00:55:27,423 +it'll go and search. This is asynchronous, + +1108 +00:55:27,425 --> 00:55:30,626 +cuz it's gonna go out on the internet to look this up. But + +1109 +00:55:30,628 --> 00:55:32,961 +it'll come back and give you a bunch of, + +1110 +00:55:32,963 --> 00:55:38,734 +locations that might match this search. Okay? Okay. + +1111 +00:55:38,903 --> 00:55:41,470 +Similarly you can asked for the directions you can + +1112 +00:55:41,472 --> 00:55:44,273 +say I wanna go from here to here and I'm gonna drive, + +1113 +00:55:44,275 --> 00:55:46,942 +give me directions, and it will give you this thing + +1114 +00:55:46,944 --> 00:55:49,845 +called MKRoute with also have turn by turn directions. + +1115 +00:55:49,847 --> 00:55:53,982 +And also have an MKPolyline which is an object which will + +1116 +00:55:53,984 --> 00:55:56,652 +draw this blue line right here Okay, and + +1117 +00:55:56,654 --> 00:55:59,888 +how do you get this blue line showing on here? + +1118 +00:55:59,890 --> 00:56:02,624 +You're gonna use another feature called overlays, okay. + +1119 +00:56:02,626 --> 00:56:05,728 +Overlays are very much like annotations, but instead of + +1120 +00:56:05,730 --> 00:56:09,064 +you have view for annotation, you have overlay view for + +1121 +00:56:09,066 --> 00:56:11,734 +annotation or renderer for annotation. + +1122 +00:56:11,736 --> 00:56:15,137 +Okay, and this renderer could be something like a polyline + +1123 +00:56:15,139 --> 00:56:17,506 +renderer, and if you have a polyline renderer, and + +1124 +00:56:17,508 --> 00:56:21,643 +you give it an MKPolyline that comes from that root thing, + +1125 +00:56:21,645 --> 00:56:24,146 +you can draw that root, okay? + +1126 +00:56:24,148 --> 00:56:26,148 +You also use overlays for your on own thing, + +1127 +00:56:26,150 --> 00:56:29,785 +if you wanna draw a bounding area around something, or + +1128 +00:56:29,787 --> 00:56:33,255 +you wanna draw your own path of where you went, you can do + +1129 +00:56:33,257 --> 00:56:36,492 +all that with overlays. Okay if you wanna do that in your + +1130 +00:56:36,494 --> 00:56:38,761 +final project, it'll count as not covered in lecture, + +1131 +00:56:38,763 --> 00:56:39,728 +cuz I'm not really covering it, + +1132 +00:56:39,730 --> 00:56:41,130 +I'm just telling you it's there, okay? + +1133 +00:56:41,132 --> 00:56:42,431 +Same thing as local search and + +1134 +00:56:42,433 --> 00:56:46,268 +all these things I've kind of glossed over here, okay? + +1135 +00:56:46,270 --> 00:56:49,104 +These are some of the built-in renderers, polyline, + +1136 +00:56:49,106 --> 00:56:54,076 +also circles, polygons, tiling, etc. Okay, + +1137 +00:56:54,078 --> 00:56:56,945 +so that's it. Now we're gonna start a demo that's gonna last + +1138 +00:56:56,947 --> 00:57:01,650 +across both lectures here, and we're gonna start by just + +1139 +00:57:01,652 --> 00:57:05,721 +doing a simple app that takes some waypoints and throws them + +1140 +00:57:05,723 --> 00:57:09,291 +on a map, so we can see how to do that. Also on Wednesday, in + +1141 +00:57:09,293 --> 00:57:12,394 +addition to finishing up this demo I'm gonna cover the last + +1142 +00:57:12,396 --> 00:57:13,996 +topic of the quarter which is persistence, + +1143 +00:57:13,998 --> 00:57:15,798 +which is basically how to store things in the file + +1144 +00:57:15,800 --> 00:57:21,537 +system, right? Opening files and all that business. Okay, + +1145 +00:57:21,539 --> 00:57:24,873 +so let's go start a new app here. + +1146 +00:57:24,875 --> 00:57:29,044 +We're gonna create a brand new one. We'll create on iOS app, + +1147 +00:57:29,046 --> 00:57:33,015 +Single View, as usual. We'll call this one Trax, okay? + +1148 +00:57:33,017 --> 00:57:37,052 +Cuz it's gonna keep track of where you have been. + +1149 +00:57:37,054 --> 00:57:40,923 +We'll make it a Universal app, so it works on iPhone and + +1150 +00:57:40,925 --> 00:57:46,595 +iPad. There we go, we'll put it in our standard location. + +1151 +00:57:46,831 --> 00:57:50,265 +All right, so here's Trax. In the storyboard right here + +1152 +00:57:50,267 --> 00:57:54,303 +I'm going to, do my standard thing. We're gonna move, + +1153 +00:57:54,305 --> 00:57:58,373 +some of these things off to Supporting Files here. + +1154 +00:57:58,375 --> 00:57:58,740 +Supporting Files. + +1155 +00:57:58,742 --> 00:58:01,844 +We're not gonna be needing to do anything in AppDelegate, so + +1156 +00:58:01,846 --> 00:58:04,513 +I'll move it off to Supporting flies, Files here. + +1157 +00:58:04,515 --> 00:58:07,883 +In my storyboard, I actually don't want my ViewController + +1158 +00:58:07,885 --> 00:58:10,319 +here to be called generic View Controller. + +1159 +00:58:10,321 --> 00:58:13,856 +So I'm gonna rename it to be GPXViewController, + +1160 +00:58:13,858 --> 00:58:16,492 +cuz what we're gonna do is take a GPX file which, + +1161 +00:58:16,494 --> 00:58:19,194 +like I said before, is just a file that contains a bunch + +1162 +00:58:19,196 --> 00:58:21,597 +of GPS coordinates, and we're gonna put it on our map. + +1163 +00:58:21,599 --> 00:58:26,034 +So we're gonna call this our GPXViewController, so + +1164 +00:58:26,036 --> 00:58:28,537 +I'm gonna rename it here as well, + +1165 +00:58:28,539 --> 00:58:31,206 +and also in my storyboard and go here to + +1166 +00:58:31,208 --> 00:58:35,978 +the Identity Inspector change this to GPXViewController. + +1167 +00:58:35,980 --> 00:58:40,782 +Okay, now let's also go ahead and build our UI here. + +1168 +00:58:40,784 --> 00:58:44,019 +Our UI is gonna be all map, all the time. Okay, our entire + +1169 +00:58:44,021 --> 00:58:48,390 +UI is just gonna be a gigantic map. So I'm gonna go down to + +1170 +00:58:48,392 --> 00:58:50,592 +my object palette down here and try and find map, + +1171 +00:58:50,594 --> 00:58:53,262 +actually, I'm gonna search for it by just typing map. + +1172 +00:58:53,264 --> 00:58:56,265 +Here it is, a Map Kit View, and you drag that out and + +1173 +00:58:56,267 --> 00:59:00,836 +put it here. Make it fill the entire MVC scene. + +1174 +00:59:00,838 --> 00:59:03,705 +Of course, we'll do Reset to Suggested Constraints, and + +1175 +00:59:03,707 --> 00:59:06,441 +we'll jump over here to our size inspector and make sure + +1176 +00:59:06,443 --> 00:59:09,411 +it did the right thing. Sure looks like it did. Let's go + +1177 +00:59:09,413 --> 00:59:12,748 +ahead and make an outlet to this from our controller. So + +1178 +00:59:12,750 --> 00:59:17,052 +I'm just gonna Ctrl+drag in here. I'll call it my mapView. + +1179 +00:59:17,054 --> 00:59:20,756 +Okay, you can see that it's a type MKMapView right there. So + +1180 +00:59:20,758 --> 00:59:25,961 +we have our Map View. Let's go ahead and when our mapView + +1181 +00:59:25,963 --> 00:59:29,197 +is set, let's go ahead and configure our mapView what we + +1182 +00:59:29,199 --> 00:59:35,337 +want it to look like. So how about the mapView's, mapType. + +1183 +00:59:35,806 --> 00:59:38,206 +And see it's not doing escape completion here. + +1184 +00:59:38,208 --> 00:59:40,842 +Why not? Import MapKit. + +1185 +00:59:40,844 --> 00:59:44,012 +Okay, just like CloudKit, it's a separate framework. + +1186 +00:59:44,014 --> 00:59:45,981 +We need it, or it's not gonna know any of these types. + +1187 +00:59:45,983 --> 00:59:49,885 +So we'll set our mapType to be Satellite, okay, + +1188 +00:59:49,887 --> 00:59:54,890 +satellite images. Let's set our delegate, + +1189 +00:59:54,892 --> 00:59:59,361 +of course. Nothing works in a mapView without a delegate, so + +1190 +00:59:59,363 --> 01:00:02,030 +we absolutely have to use delegate, and + +1191 +01:00:02,032 --> 01:00:05,267 +that means we'll have to be an MKMapViewDelegate. + +1192 +01:00:05,269 --> 01:00:09,171 +All right, so we have our mapview set up here nicely, + +1193 +01:00:09,173 --> 01:00:14,876 +oops. Okay, so now we need our model. + +1194 +01:00:14,878 --> 01:00:17,279 +What's gonna be our model to this thing? + +1195 +01:00:17,281 --> 01:00:22,284 +It's going to be a gpxURL. Okay, so this is gonna be + +1196 +01:00:22,286 --> 01:00:26,054 +the URL to a GPX file, a file that contains coordinates. + +1197 +01:00:26,056 --> 01:00:27,823 +And we're just gonna open that file, + +1198 +01:00:27,825 --> 01:00:30,592 +look at all the GPX coordinates and display them. + +1199 +01:00:30,594 --> 01:00:35,097 +And in fact, let's go ahead and in our viewDidLoad here + +1200 +01:00:35,099 --> 01:00:40,369 +just load one up. So let's see, gpxURL equals, + +1201 +01:00:40,371 --> 01:00:45,674 +how about this one right here, a string, which is + +1202 +01:00:45,676 --> 01:00:51,246 +http://cs193p.stanford.edu/Va- cation, + +1203 +01:00:51,248 --> 01:00:55,951 +oops, Vacation.gpx. Okay, so that's just a, + +1204 +01:00:55,953 --> 01:01:01,390 +a URL I have around there that we can look at. Now this + +1205 +01:01:01,392 --> 01:01:05,560 +is an http, so we'd better go over to our info.plist, + +1206 +01:01:05,562 --> 01:01:10,232 +right here, and do the thing we always do here where we add + +1207 +01:01:10,234 --> 01:01:13,535 +our App Transport settings right here. + +1208 +01:01:13,537 --> 01:01:18,507 +Let's add Arbitrary Loads allowed, and we will + +1209 +01:01:18,509 --> 01:01:21,977 +say YES. Everyone understand why we're doing that, + +1210 +01:01:21,979 --> 01:01:26,281 +same thing we had to do with smash tag there. All right, so + +1211 +01:01:26,283 --> 01:01:29,918 +we're all set up here, what are we gonna do when this is + +1212 +01:01:29,920 --> 01:01:35,323 +set? Okay, so when our model is set, when this URL is set, + +1213 +01:01:35,325 --> 01:01:40,529 +what are we gonna need to do here to make this work? Well, + +1214 +01:01:40,531 --> 01:01:43,265 +if they set the URL equal to something, so + +1215 +01:01:43,267 --> 01:01:48,236 +they didn't set it to be nil let's say. Then really what + +1216 +01:01:48,238 --> 01:01:52,841 +I need to do is parse this file, this URL somehow. And + +1217 +01:01:52,843 --> 01:01:56,545 +to do that, I'm going to introduce a little class that + +1218 +01:01:56,547 --> 01:02:00,849 +I wrote called GPX, which will parse a GPX file and then give + +1219 +01:02:00,851 --> 01:02:03,618 +you all the waypoints. Okay, so let's go ahead and + +1220 +01:02:03,620 --> 01:02:08,090 +grab that file. It's right here, it's called GPX.swift. + +1221 +01:02:08,092 --> 01:02:10,492 +Copy it in. Take a brief look at this thing, + +1222 +01:02:10,494 --> 01:02:15,163 +what it does. All right, here's GPX, let's go ahead and + +1223 +01:02:15,165 --> 01:02:18,133 +look at it just at its generated interface + +1224 +01:02:18,135 --> 01:02:23,371 +here. No need to look at the code there. + +1225 +01:02:23,373 --> 01:02:26,208 +All right, so here's the GPX, this class. And + +1226 +01:02:26,210 --> 01:02:30,545 +the main thing it has is this, this var waypoints, + +1227 +01:02:30,547 --> 01:02:34,249 +which is a array of GPX.Waypoint. + +1228 +01:02:34,251 --> 01:02:36,952 +Let's go look at the GPX waypoint, that's right here. + +1229 +01:02:36,954 --> 01:02:40,756 +So, the Waypoint is latitude and longitude, of course, + +1230 +01:02:40,758 --> 01:02:44,659 +kind of some information about this waypoint, the date + +1231 +01:02:44,661 --> 01:02:48,497 +the waypoint was captured. And it's also an entry, + +1232 +01:02:48,499 --> 01:02:51,233 +this Waypoint is also an entry, which is this thing. + +1233 +01:02:51,235 --> 01:02:54,603 +The entry can have any number of hyperlinks. So these would + +1234 +01:02:54,605 --> 01:02:58,240 +be like URLs to photos or video that I might have taken + +1235 +01:02:58,242 --> 01:03:02,611 +at this location when I was on my trek or whatever. Also it + +1236 +01:03:02,613 --> 01:03:06,381 +has a name, which is the name of this waypoint, okay? May or + +1237 +01:03:06,383 --> 01:03:11,686 +may not have a name, but if it does this is the name. Okay, + +1238 +01:03:11,688 --> 01:03:14,623 +these links by the way, these GPX links is right here. + +1239 +01:03:14,625 --> 01:03:18,593 +It's basically just URLs, hrefs, here, + +1240 +01:03:18,595 --> 01:03:21,797 +okay. All right, so that's it. That's all this thing does is, + +1241 +01:03:21,799 --> 01:03:25,333 +main thing is this, this array of waypoints, okay? So let's + +1242 +01:03:25,335 --> 01:03:29,704 +go back to our controller here. So we do this GPX.parse. + +1243 +01:03:29,706 --> 01:03:34,576 +Notice that this parse method in GPX is asynchronous. + +1244 +01:03:34,578 --> 01:03:37,112 +It parses that file, and then later it calls you back. + +1245 +01:03:37,114 --> 01:03:40,682 +It's a very nice asynchronous method in that it always calls + +1246 +01:03:40,684 --> 01:03:42,284 +you back on the main queue, okay, so + +1247 +01:03:42,286 --> 01:03:45,187 +we don't have to dispatch async or anything here. And + +1248 +01:03:45,189 --> 01:03:50,025 +the only argument that's given when you do it is a GPX, which + +1249 +01:03:50,027 --> 01:03:54,596 +is an instance of this class, and it has those waypoints. + +1250 +01:03:54,598 --> 01:03:57,632 +So, what are we gonna do with these waypoints when they come + +1251 +01:03:57,634 --> 01:04:01,937 +back? Well, if the, if it was able to parse it, basically if + +1252 +01:04:01,939 --> 01:04:06,241 +this thing came back and it wasn't nil, then we're going + +1253 +01:04:06,243 --> 01:04:11,546 +to add these waypoints to ourself. Waypoints, + +1254 +01:04:11,548 --> 01:04:14,583 +okay, so we're gonna have to add, do this method here. + +1255 +01:04:14,585 --> 01:04:17,252 +Also every time someone said that I'm also gonna clear any + +1256 +01:04:17,254 --> 01:04:20,522 +waypoints that I already have. So I'm gonna implement these + +1257 +01:04:20,524 --> 01:04:24,292 +two methods right here. Okay everybody cool with that? So + +1258 +01:04:24,294 --> 01:04:27,262 +we're just getting those GPS waypoints out of this GPX + +1259 +01:04:27,264 --> 01:04:29,397 +file. So we're gonna implement these two methods. So + +1260 +01:04:29,399 --> 01:04:34,035 +let's do private func clearWaypoints. Okay, so for + +1261 +01:04:34,037 --> 01:04:37,072 +clearWaypoints I just wanna remove all the annotations off + +1262 +01:04:37,074 --> 01:04:40,375 +my map, remember the map just shows annotations? So + +1263 +01:04:40,377 --> 01:04:40,842 +I'm gonna remove them all. + +1264 +01:04:40,844 --> 01:04:44,713 +I'm gonna say mapView removeAnnotations which is + +1265 +01:04:44,715 --> 01:04:47,816 +the mapView's current annotations, okay, + +1266 +01:04:47,818 --> 01:04:52,187 +whatever the mapView currently has. Notice I'm doing this + +1267 +01:04:52,189 --> 01:04:55,824 +MapView question mark here, that's because if this happens + +1268 +01:04:55,826 --> 01:04:59,828 +in like a perform, prepare for segue or something like that, + +1269 +01:04:59,830 --> 01:05:02,030 +then my mapView wouldn't be wired up yet. + +1270 +01:05:02,032 --> 01:05:04,799 +So I don't want this to fail, I just want you to do nothing. + +1271 +01:05:04,801 --> 01:05:08,436 +So that's why I'm doing MapView?. Okay and + +1272 +01:05:08,438 --> 01:05:13,775 +then we have the addWaypoints, private func addWaypoints and + +1273 +01:05:13,777 --> 01:05:18,146 +this one is going to take an array. Waypoints, + +1274 +01:05:18,148 --> 01:05:23,618 +which is an array of these GPX.Waypoint objects. Okay, + +1275 +01:05:23,620 --> 01:05:25,720 +so what do we wanna do in addWaypoints? + +1276 +01:05:25,722 --> 01:05:28,990 +Well, we just want to add them as annotations. So I'm just + +1277 +01:05:28,992 --> 01:05:33,228 +gonna say addAnnotations, these waypoints, right? + +1278 +01:05:33,230 --> 01:05:37,532 +MapView, the other thing I'm gonna do is there's a way in + +1279 +01:05:37,534 --> 01:05:41,369 +the MapView to say, show me all of these annotations. + +1280 +01:05:41,371 --> 01:05:46,474 +You say showAnnotations, showAnnotations, and + +1281 +01:05:46,476 --> 01:05:47,342 +it takes some annotations, and + +1282 +01:05:47,344 --> 01:05:49,978 +I'll just give those same waypoints. And + +1283 +01:05:49,980 --> 01:05:50,645 +I'll say animated true, and + +1284 +01:05:50,647 --> 01:05:54,582 +what this will do is zoom the map to show these annotations, + +1285 +01:05:54,584 --> 01:06:00,255 +okay. Now, a couple errors here. What are these errors? + +1286 +01:06:00,257 --> 01:06:03,758 +Cannot convert value of array of GPS Waypoint to + +1287 +01:06:03,760 --> 01:06:07,862 +expected argument which is array of MKAnnotation. + +1288 +01:06:07,864 --> 01:06:11,866 +Ha! Right I said that the mapView takes MKAnnotations, + +1289 +01:06:11,868 --> 01:06:15,670 +and these are GPS Waypoints. They're not MKAnnotations. But + +1290 +01:06:15,672 --> 01:06:20,208 +we can easily turn a GPX Waypoint into an MKAnnotation + +1291 +01:06:20,210 --> 01:06:23,011 +as long as we get it to implement those three methods, + +1292 +01:06:23,013 --> 01:06:25,880 +right? So how are we gonna do that? Well let's create + +1293 +01:06:25,882 --> 01:06:29,050 +another little file and we're just gonna add protocol + +1294 +01:06:29,052 --> 01:06:33,121 +conformance via an extension which I talked about earlier + +1295 +01:06:33,123 --> 01:06:35,991 +in the quarter but we haven't seen it actually happen. So + +1296 +01:06:35,993 --> 01:06:36,925 +here I'm gonna create a Swift file. + +1297 +01:06:36,927 --> 01:06:41,096 +I'm gonna call it mkgpx because it's MK annotated, + +1298 +01:06:41,098 --> 01:06:45,000 +map kit stuff having to do with this GPX class right + +1299 +01:06:45,002 --> 01:06:49,938 +here. And I'm going to import MapKit, MK, yeah MapKit. + +1300 +01:06:49,940 --> 01:06:51,740 +All right, and what am I gonna do, + +1301 +01:06:51,742 --> 01:06:55,043 +I'm gonna create an extension to GPX.Waypoint, and + +1302 +01:06:55,045 --> 01:06:58,480 +it's going to implement the protocol MKAnnotation. + +1303 +01:06:58,482 --> 01:07:00,382 +That's what this extension is going to do. So + +1304 +01:07:00,384 --> 01:07:05,453 +this is how we can implement a protocol via an extension. + +1305 +01:07:05,455 --> 01:07:07,288 +Okay now all you need to do is implement these things. + +1306 +01:07:07,290 --> 01:07:12,594 +Remember there's coordinates that we have to do which is + +1307 +01:07:12,596 --> 01:07:17,665 +a CLLocationCoordinate2D. We have to implement title, which + +1308 +01:07:17,667 --> 01:07:20,902 +is a String, optional but we have to implement it and + +1309 +01:07:20,904 --> 01:07:23,805 +then there's subtitle which can be any subtitle + +1310 +01:07:23,807 --> 01:07:27,075 +information we want, okay, which is also a String. + +1311 +01:07:27,077 --> 01:07:29,644 +So we just have to implement these three things and + +1312 +01:07:29,646 --> 01:07:32,113 +then we will have successfully, + +1313 +01:07:32,282 --> 01:07:36,951 +added the MKAnnotation conformant to Waypoint. + +1314 +01:07:36,953 --> 01:07:38,486 +So how are we going to implement these things? + +1315 +01:07:38,488 --> 01:07:41,189 +Okay well coordinate this is not coordination this is + +1316 +01:07:41,191 --> 01:07:44,459 +coordinate okay? The coordinate is easy to + +1317 +01:07:44,461 --> 01:07:47,662 +implement because the GPXWaypoint knows latitude and + +1318 +01:07:47,664 --> 01:07:48,029 +So I'm just gonna create a new LocationCoordinate2D okay, and + +1319 +01:07:48,031 --> 01:07:51,599 +longitude. + +1320 +01:07:51,601 --> 01:07:54,803 +it's gonna have latitude which is the latitude, + +1321 +01:07:54,805 --> 01:07:58,306 +it's green there, you see? Because it's a var, + +1322 +01:07:58,308 --> 01:08:03,244 +in this class, and then longitude. Okay, so + +1323 +01:08:03,246 --> 01:08:05,346 +that was easy. How about the title? + +1324 +01:08:05,348 --> 01:08:07,916 +Well, all these GPX Waypoints have that name, so + +1325 +01:08:07,918 --> 01:08:11,853 +I'm just gonna return the name of the GPX Waypoint and + +1326 +01:08:11,855 --> 01:08:16,357 +then they also have this thing called info, which is just + +1327 +01:08:16,359 --> 01:08:17,992 +kind of information about the Waypoint. + +1328 +01:08:17,994 --> 01:08:22,263 +That would be a good subtitle, okay? So just like that I've + +1329 +01:08:22,265 --> 01:08:25,834 +turned GPX Waypoints into MKAnnotations and + +1330 +01:08:25,836 --> 01:08:28,636 +this is how you use the map. You take usually something + +1331 +01:08:28,638 --> 01:08:30,905 +you already have and make it implement this. + +1332 +01:08:30,907 --> 01:08:33,374 +Now you could create a new class that all it does + +1333 +01:08:33,376 --> 01:08:35,710 +is implement MKAnnotation that's fine too, but + +1334 +01:08:35,712 --> 01:08:38,480 +generally, usually have something lying around that + +1335 +01:08:38,482 --> 01:08:40,248 +you can turn into an MKAnnotation. And + +1336 +01:08:40,250 --> 01:08:44,419 +notice as soon as I do that, no more errors here, okay, + +1337 +01:08:44,421 --> 01:08:48,456 +because this is now an array of MKAnnotation, okay, + +1338 +01:08:48,458 --> 01:08:53,027 +all right. So let's go ahead and run this, + +1339 +01:08:53,029 --> 01:08:56,698 +see what happens, lets go here, iPhone6, run, + +1340 +01:08:56,700 --> 01:08:58,967 +see if it can open this GPX file up and + +1341 +01:08:58,969 --> 01:09:05,874 +show us these waypoints. Up, sure enough there it is, + +1342 +01:09:05,876 --> 01:09:08,510 +and it even did that showAnnotations right here, + +1343 +01:09:08,512 --> 01:09:10,378 +okay. That zoomed to where it is so + +1344 +01:09:10,380 --> 01:09:11,146 +it's showing all the annotations + +1345 +01:09:11,148 --> 01:09:13,915 +it found in that GPX file. Let's see if we can see where + +1346 +01:09:13,917 --> 01:09:19,387 +we are here. Zoom out. Looks like we are in what, what is, + +1347 +01:09:19,389 --> 01:09:25,960 +anyone know where that is? Recognize that coastline? + +1348 +01:09:25,962 --> 01:09:29,497 +Canada! Yeah, there's the United States, here's Canada. + +1349 +01:09:29,499 --> 01:09:32,333 +Okay? So here we are, we got these things in Canada. Now, + +1350 +01:09:32,335 --> 01:09:35,170 +if we click on some of these. Let's click on some, + +1351 +01:09:35,172 --> 01:09:38,540 +see what happens. So I click, notice we get the name and + +1352 +01:09:38,542 --> 01:09:42,544 +the info right. The title and the subtitle got it. + +1353 +01:09:42,546 --> 01:09:47,615 +Now I happen to know that this GPX file has URLs of photos + +1354 +01:09:47,617 --> 01:09:52,020 +that were taken at all of these locations, okay? + +1355 +01:09:52,022 --> 01:09:55,056 +So the next thing we'd like to do is see those. Okay and + +1356 +01:09:55,058 --> 01:09:58,226 +what I'm gonna try to do is put them as a thumbnail image + +1357 +01:09:58,228 --> 01:10:02,297 +inside my left accessory view of these call outs. + +1358 +01:10:02,299 --> 01:10:06,534 +Now to do that we're going to need to override or implement + +1359 +01:10:06,536 --> 01:10:09,270 +that method viewForAnnotation. Notice we didn't implement + +1360 +01:10:09,272 --> 01:10:11,940 +viewForAnnotation which is like self erode index path, + +1361 +01:10:11,942 --> 01:10:14,642 +and when you don't you get this really simple call + +1362 +01:10:14,644 --> 01:10:16,611 +out that has no left or right accessory view, + +1363 +01:10:16,613 --> 01:10:18,479 +just has the title or subtitle, okay. + +1364 +01:10:18,481 --> 01:10:21,382 +But we need to implement it so we can put a left accessory + +1365 +01:10:21,384 --> 01:10:23,785 +view which is going to be a button. I'm gonna have it be a + +1366 +01:10:23,787 --> 01:10:25,920 +button because I'm gonna want to be able to click on it in + +1367 +01:10:25,922 --> 01:10:29,824 +and segue to show me the image later in the demo probably + +1368 +01:10:29,826 --> 01:10:33,261 +next lecture. All right, so how are we gonna do this? + +1369 +01:10:33,263 --> 01:10:36,264 +Well we have to implement that method viewForAnnotations. + +1370 +01:10:36,266 --> 01:10:38,566 +So let's see if we can find it. There it is, okay. + +1371 +01:10:38,568 --> 01:10:42,904 +MKMap viewForAnnotation, okay? It's asking us to provide + +1372 +01:10:42,906 --> 01:10:47,141 +an annotation view for this annotation. So first, I'm + +1373 +01:10:47,143 --> 01:10:49,644 +going to see if I can get it, and I'm actually gonna do + +1374 +01:10:49,646 --> 01:10:53,414 +something kind of interesting here. I'm going to type this. + +1375 +01:10:53,416 --> 01:10:56,084 +Now, normally you would say why are you putting a type + +1376 +01:10:56,086 --> 01:10:58,886 +here. Because you could just say view equals something and + +1377 +01:10:58,888 --> 01:11:01,489 +it would automatically infer the type. Well the reason is + +1378 +01:11:01,491 --> 01:11:05,727 +cuz I want it to be implicitly unwrapped. Okay if I didn't + +1379 +01:11:05,729 --> 01:11:08,396 +put this here, okay, then it would be an optional + +1380 +01:11:08,398 --> 01:11:10,965 +because the thing I'm going to call returns an optional, but + +1381 +01:11:10,967 --> 01:11:12,767 +I want it implicitly unwrapped so + +1382 +01:11:12,769 --> 01:11:14,035 +the rest of my method method looks like. + +1383 +01:11:14,037 --> 01:11:16,838 +The code and the rest of my method. Okay so + +1384 +01:11:16,840 --> 01:11:20,174 +I'm gonna do here. I'm gonna ask the MapView to dequeue + +1385 +01:11:20,176 --> 01:11:22,710 +a reusable annotationView with an identifier. + +1386 +01:11:22,712 --> 01:11:24,779 +Now to be nice I have some constants, so + +1387 +01:11:24,781 --> 01:11:28,182 +let's put them on the bottom here. Okay so + +1388 +01:11:28,184 --> 01:11:32,120 +here's my constants that I have and I have a constant for + +1389 +01:11:32,122 --> 01:11:36,357 +the reuse identifier here. Call it waypoint and say + +1390 +01:11:36,359 --> 01:11:42,297 +Constants.AnnotationViewReuse- Identifier. + +1391 +01:11:42,299 --> 01:11:43,498 +Okay, so that's de-queueing it. + +1392 +01:11:43,500 --> 01:11:46,934 +Now what if this is the first pin it's ever doing? It's not + +1393 +01:11:46,936 --> 01:11:49,871 +going to be able to de-queue. There's no pins to reuse. + +1394 +01:11:49,873 --> 01:11:51,139 +There's none that were used and + +1395 +01:11:51,141 --> 01:11:53,841 +are now left over. So now we're gonna have to say if + +1396 +01:11:53,843 --> 01:11:57,078 +the view Equals nil we have to create this thing because + +1397 +01:11:57,080 --> 01:12:00,081 +there's no prototypes like table view. So I'm going + +1398 +01:12:00,083 --> 01:12:04,185 +to create the thing by saying I want an MKPinAnnotationView. + +1399 +01:12:04,187 --> 01:12:06,954 +And the arguments to initialize here + +1400 +01:12:06,956 --> 01:12:10,158 +are the annotation which is this annotation right here. + +1401 +01:12:10,160 --> 01:12:13,394 +That's the annotation we're creating a view for. And + +1402 +01:12:13,396 --> 01:12:15,630 +we wanna use the same ReuseIdentifier right here, + +1403 +01:12:15,632 --> 01:12:19,367 +because in future, we want this one that we're creating + +1404 +01:12:19,369 --> 01:12:23,004 +to be in the reuse queue, okay? And + +1405 +01:12:23,006 --> 01:12:26,874 +I'm also gonna say that we can show callouts. + +1406 +01:12:27,210 --> 01:12:28,843 +Okay, because by default, I believe, + +1407 +01:12:28,845 --> 01:12:30,611 +if you create an MKPinAnnotationView, + +1408 +01:12:30,613 --> 01:12:32,447 +it won't show the callouts when you click on it. + +1409 +01:12:32,449 --> 01:12:33,948 +So I wanna make sure it does show the callouts, + +1410 +01:12:33,950 --> 01:12:36,684 +cuz that's where my left accessory view is gonna be. + +1411 +01:12:36,686 --> 01:12:40,154 +Otherwise, if I was able to dequeue one here then I need + +1412 +01:12:40,156 --> 01:12:45,259 +to change the annotation in it to be this annotation here. + +1413 +01:12:46,296 --> 01:12:48,062 +Okay? All right, + +1414 +01:12:48,064 --> 01:12:51,032 +now we've got this view, this is basically exactly what's + +1415 +01:12:51,034 --> 01:12:53,568 +happening if we don't implement this method. Okay? + +1416 +01:12:53,570 --> 01:12:56,471 +And in fact, if I run this, if I just return this view and + +1417 +01:12:56,473 --> 01:12:58,840 +run it, you're gonna see it looks exactly the same, + +1418 +01:12:58,842 --> 01:13:03,911 +okay the system basically will do exactly this for you. See? + +1419 +01:13:03,913 --> 01:13:07,515 +If you don't implement it okay? So it's doing exactly + +1420 +01:13:07,517 --> 01:13:12,353 +the same thing. So now,let's add this left annotation view + +1421 +01:13:12,355 --> 01:13:16,858 +which wants to be a ui button. So how are we gonna do that? + +1422 +01:13:16,860 --> 01:13:20,795 +Okay well, let's just first of all let's set the left + +1423 +01:13:20,797 --> 01:13:24,899 +leftCalloutAccessoryView to be nil. I'm just going to put + +1424 +01:13:24,901 --> 01:13:29,570 +this little button in there if the GPS point has a photo. + +1425 +01:13:29,572 --> 01:13:31,305 +If it doesn't have a thumbnail image, + +1426 +01:13:31,307 --> 01:13:32,607 +I don't want that button to + +1427 +01:13:32,609 --> 01:13:34,509 +be there empty. So, first of all, + +1428 +01:13:34,511 --> 01:13:35,376 +I'm going to clear it out. + +1429 +01:13:35,378 --> 01:13:39,514 +Then I'm going to say if I can get the waypoint, which I + +1430 +01:13:39,516 --> 01:13:42,683 +should be able to because it's just the annotation + +1431 +01:13:42,685 --> 01:13:47,755 +As a GPX waypoint, right? That's what the waypoint is. + +1432 +01:13:47,757 --> 01:13:50,658 +This annotation, all of our annotations are that. So + +1433 +01:13:50,660 --> 01:13:51,826 +as long I'm able to get that waypoint, + +1434 +01:13:51,828 --> 01:13:55,029 +which I should be able to, then if the waypoint has + +1435 +01:13:55,031 --> 01:14:01,636 +a thumbnail URL, if that doesn't equal + +1436 +01:14:01,638 --> 01:14:05,440 +nil Now this is something I'm gonna have to implement okay. + +1437 +01:14:05,442 --> 01:14:06,941 +Because it doesn't have that method, so + +1438 +01:14:06,943 --> 01:14:08,543 +I'm going to have to implement that method. + +1439 +01:14:08,545 --> 01:14:11,512 +Then, I'm gonna set my left column so AccessoryView + +1440 +01:14:11,514 --> 01:14:15,783 +to be a UI button. Whose frame is this constant. + +1441 +01:14:15,785 --> 01:14:18,453 +Unfortunately I have to do a constant here for + +1442 +01:14:18,455 --> 01:14:21,956 +this and I'll show that in a second. The constant for + +1443 +01:14:21,958 --> 01:14:25,593 +this is 59 by 59. This is one of the few cases + +1444 +01:14:25,595 --> 01:14:28,329 +in IOS where you're gonna use a magic number. But + +1445 +01:14:28,331 --> 01:14:30,498 +unfortunately, they're just doesn't seem to be anyway, + +1446 +01:14:30,500 --> 01:14:34,135 +at least that I've ever found, to ask the map views and + +1447 +01:14:34,137 --> 01:14:38,239 +notation view how big is your call-out so that I can make + +1448 +01:14:38,241 --> 01:14:41,375 +the thing the right size. So, I just Know that 59 by + +1449 +01:14:41,377 --> 01:14:43,978 +59 works. I hope Apple doesn't change the size of that + +1450 +01:14:43,980 --> 01:14:46,380 +callout in the future, cuz it might break this code. + +1451 +01:14:46,382 --> 01:14:47,715 +That's why you never want magic numbers, + +1452 +01:14:47,717 --> 01:14:50,985 +but unfortunately, we're kind of stuck with one here. + +1453 +01:14:50,987 --> 01:14:53,488 +So, we have this error because thumbnailURL is not + +1454 +01:14:53,490 --> 01:14:56,557 +implemented. So, how are we gonna implement thumbnailURL? + +1455 +01:14:56,559 --> 01:14:59,827 +Well, I told you that every GPX waypoint can have + +1456 +01:14:59,829 --> 01:15:02,630 +a number of links associated with one of them, + +1457 +01:15:02,632 --> 01:15:04,632 +one of my view thumbnailURL. So + +1458 +01:15:04,634 --> 01:15:08,803 +I'm gonna go back to my MKGPX right here and + +1459 +01:15:08,805 --> 01:15:11,806 +I'm gonna add this var thumbnailURL, which + +1460 +01:15:11,808 --> 01:15:15,776 +is gonna be an NSURL. And this is gonna be optional because, + +1461 +01:15:15,778 --> 01:15:18,546 +it might be that it doesn't have one. Which is fine, + +1462 +01:15:18,548 --> 01:15:21,215 +now I just want to show this little side button. And + +1463 +01:15:21,217 --> 01:15:24,352 +to implement this, I'm gonna implement a little method + +1464 +01:15:24,354 --> 01:15:28,422 +here, a private func, which goes through the links and + +1465 +01:15:28,424 --> 01:15:31,425 +tries to find one of the type thumbnail. So it's gonna be + +1466 +01:15:31,427 --> 01:15:36,464 +called getImageURLofType. It's gonna take a certain type, + +1467 +01:15:36,466 --> 01:15:39,367 +which is just a string like thumbnail or something like + +1468 +01:15:39,369 --> 01:15:45,640 +that. And it's going to return an NSURL possibly if + +1469 +01:15:45,642 --> 01:15:46,474 +you can find such a thing, and + +1470 +01:15:46,476 --> 01:15:51,345 +I'm just gonna go through the links in the GPXWayPoint. And + +1471 +01:15:51,347 --> 01:15:55,082 +if the links type equals the type am asking for then am + +1472 +01:15:55,084 --> 01:15:58,619 +just gonna return the links URL, and if I can't do any of + +1473 +01:15:58,621 --> 01:16:02,924 +that I'll return nil. Okay? So this gets an ImageURLofType, + +1474 +01:16:02,926 --> 01:16:07,662 +so here I'm gonna get the ImageURLofTyp. + +1475 +01:16:07,664 --> 01:16:10,231 +So if it's able to get a thumbnail image, woo hoo, + +1476 +01:16:10,233 --> 01:16:13,568 +we're good to go, otherwise it'll be returning nil here. + +1477 +01:16:13,570 --> 01:16:17,738 +While I'm here I'm gonna have another one called imageURL + +1478 +01:16:17,740 --> 01:16:20,708 +which gets the URL of the image large. + +1479 +01:16:20,710 --> 01:16:23,578 +Okay, not a thumbnail of it, but a big, large image of it. + +1480 +01:16:23,580 --> 01:16:28,316 +And so, that's the type large. Okay, so these are just types + +1481 +01:16:28,318 --> 01:16:33,321 +associated with that link in the GPX file, okay? So + +1482 +01:16:33,323 --> 01:16:38,659 +now we have these, we can go back here, and do this now. + +1483 +01:16:38,661 --> 01:16:40,428 +Notice that we, Sorry. + +1484 +01:16:40,430 --> 01:16:43,364 +[LAUGH] Create this leftCalloutAccessoryView here. + +1485 +01:16:43,366 --> 01:16:44,732 +I'm actually gonna give this some space, but + +1486 +01:16:44,734 --> 01:16:47,401 +we don't actually set the button's image. And + +1487 +01:16:47,403 --> 01:16:51,305 +I'm not gonna set that image until the user clicks on me. + +1488 +01:16:51,307 --> 01:16:54,675 +Okay? Soon as they click on my pin annotation view, + +1489 +01:16:54,677 --> 01:16:55,376 +it makes our callout accessory + +1490 +01:16:55,378 --> 01:16:57,345 +is gonna come up. Then I'm gonna go get the image. + +1491 +01:16:57,347 --> 01:16:58,646 +Cuz getting the image is gonna be expensive. + +1492 +01:16:58,648 --> 01:17:01,616 +Cuz I'm gonna go get it off the internet somewhere. Okay? + +1493 +01:17:01,618 --> 01:17:06,420 +So let's do that and we do that in this method here + +1494 +01:17:06,422 --> 01:17:12,026 +called did select annotation view. + +1495 +01:17:12,028 --> 01:17:14,895 +Okay, so mapview delegate method here tells us when this + +1496 +01:17:14,897 --> 01:17:18,065 +annotation view was selected. And so I'm gonna have to + +1497 +01:17:18,067 --> 01:17:21,469 +extract some things here, like I need to get that thumbnail + +1498 +01:17:21,471 --> 01:17:24,972 +image button from the left accessory view. That's just my + +1499 +01:17:24,974 --> 01:17:28,776 +left call out accessory view and it better be a ui button. + +1500 +01:17:28,778 --> 01:17:31,112 +So I'll that's what I'm doing if let here. + +1501 +01:17:31,114 --> 01:17:36,984 +I'm also going to get the url which is the gpx waypoint + +1502 +01:17:36,986 --> 01:17:42,690 +which is the annotation as a gpx waypoint okay? + +1503 +01:17:42,692 --> 01:17:47,028 +It's it's thumbnail URL that method we just implemented. + +1504 +01:17:47,030 --> 01:17:49,764 +Okay, I also need to get the image data. + +1505 +01:17:49,766 --> 01:17:54,835 +Now I'm gonna be a really bad man here and I'm going + +1506 +01:17:54,837 --> 01:18:00,708 +to do this on the main queue okay. Blocks main queue. + +1507 +01:18:00,710 --> 01:18:03,944 +You would never do this in your final projects for + +1508 +01:18:03,946 --> 01:18:09,050 +example okay. And now, I'm going to get the UI image that + +1509 +01:18:09,052 --> 01:18:18,592 +corresponds to that data. All right? + +1510 +01:18:18,594 --> 01:18:22,596 +So now I've run the gauntlet of all of these if lets and + +1511 +01:18:22,598 --> 01:18:24,899 +I have the image and I have the thumbnail image button, + +1512 +01:18:24,901 --> 01:18:28,602 +so I'm just gonna say thumbnail image button. + +1513 +01:18:28,604 --> 01:18:33,274 +SetImage to be that image for the State. Remember + +1514 +01:18:33,276 --> 01:18:35,376 +buttons have different states like highlight and state and + +1515 +01:18:35,378 --> 01:18:37,645 +whatever so I don't want the normal state which is kinda + +1516 +01:18:37,647 --> 01:18:42,817 +the default state, okay. So let's go and run that. + +1517 +01:18:47,690 --> 01:18:52,126 +Right, here we go, a click on it and sure enough now we're + +1518 +01:18:52,128 --> 01:18:56,363 +getting this thumbnail in here To that, okay? So + +1519 +01:18:56,365 --> 01:18:57,131 +that's all we have time for today. + +1520 +01:18:57,133 --> 01:18:59,667 +What we're gonna do next time is I'm gonna click on this + +1521 +01:18:59,669 --> 01:19:03,671 +button, and we're gonna Segway to the image view controller + +1522 +01:19:03,673 --> 01:19:05,806 +we have in Kissimmee. It's gonna Segway and + +1523 +01:19:05,808 --> 01:19:09,777 +show us the full size image, the large image of that thing. + +1524 +01:19:09,779 --> 01:19:12,646 +So once you have segue. Then, we'll go on and do some more + +1525 +01:19:12,648 --> 01:19:17,251 +stuff to show off some other little features. All right? + +1526 +01:19:17,253 --> 01:19:20,087 +So, see you next time. >> For + +1527 +01:19:20,089 --> 01:19:20,120 +more, please visit us at stanford.edu. + diff --git a/subtitles/18. Persistence.srt b/subtitles/18. Persistence.srt new file mode 100644 index 0000000..92276dd --- /dev/null +++ b/subtitles/18. Persistence.srt @@ -0,0 +1,5536 @@ +1 +00:00:00,001 --> 00:00:03,469 +[MUSIC] + +2 +00:00:03,471 --> 00:00:07,806 +Stanford University. >> Okay, well, + +3 +00:00:07,808 --> 00:00:12,711 +welcome to Stanford CSI93P Spring of 2016. + +4 +00:00:12,713 --> 00:00:14,947 +This is our last normal lecture. + +5 +00:00:14,949 --> 00:00:18,217 +The only lecture we have left is our alternate final, next + +6 +00:00:18,219 --> 00:00:23,088 +week. Today we are going to have a demo of all the stuff I + +7 +00:00:23,090 --> 00:00:27,760 +talked about on Monday. So, mostly that's segues. + +8 +00:00:27,762 --> 00:00:33,298 +Including ma, modal segue, popover segue, unwind segue. + +9 +00:00:33,300 --> 00:00:35,868 +And even we'll talk about the adaptive presentation, + +10 +00:00:35,870 --> 00:00:39,671 +how we adapt to horizontally compact, all that stuff. And + +11 +00:00:39,673 --> 00:00:40,672 +I'll throw a little bit of bonus in there. + +12 +00:00:40,674 --> 00:00:43,442 +We'll talk a little about visual effects, like Blur. + +13 +00:00:43,444 --> 00:00:47,513 +You'll see a lot of Blur in the UI occasionally and + +14 +00:00:47,515 --> 00:00:50,682 +I'll show you how to basically do that. And + +15 +00:00:50,684 --> 00:00:53,952 +I think that's gonna take most of the time but + +16 +00:00:53,954 --> 00:00:55,854 +if I have any time left like maybe five or + +17 +00:00:55,856 --> 00:00:58,590 +ten minutes left I'll try to do a quick tour through + +18 +00:00:58,592 --> 00:01:01,393 +persistence because creating files in the file system, + +19 +00:01:01,395 --> 00:01:03,962 +stuff like that is something a lot of people are gonna wanna + +20 +00:01:03,964 --> 00:01:06,031 +do in their final project. So I'll try and cover that. No + +21 +00:01:06,033 --> 00:01:08,901 +demo for that unfortunately, but at least maybe I can get + +22 +00:01:08,903 --> 00:01:14,006 +through the slides if the demo goes on a good pace, okay? + +23 +00:01:14,008 --> 00:01:17,443 +So here's our demo those all the things we're gonna cover. + +24 +00:01:17,445 --> 00:01:20,345 +So it's quite a quick demo, it, it, or + +25 +00:01:20,347 --> 00:01:24,850 +quite a involved demo. It's gonna be an extension of Trax, + +26 +00:01:24,852 --> 00:01:27,920 +okay, the thing that we left off with last time. + +27 +00:01:27,922 --> 00:01:29,655 +I'll run that really quick just to remind yourself, + +28 +00:01:29,657 --> 00:01:34,693 +in the last two days, what it did. So, remember that it went + +29 +00:01:34,695 --> 00:01:37,162 +out on the Internet, it grabbed a GPX file, which is + +30 +00:01:37,164 --> 00:01:40,099 +just basically a file that contains a bunch of waypoints + +31 +00:01:40,101 --> 00:01:43,035 +and possibly hyperlinks attached to the waypoints. + +32 +00:01:43,037 --> 00:01:44,670 +And it puts them on the map here so + +33 +00:01:44,672 --> 00:01:48,207 +we can scroll around and zoom in and out on them. And + +34 +00:01:48,209 --> 00:01:49,675 +we made it so that if we clicked on them, + +35 +00:01:49,677 --> 00:01:52,678 +the callout had a left accessory callout + +36 +00:01:52,680 --> 00:01:55,114 +view right here, this left accessory callout view. + +37 +00:01:55,116 --> 00:01:59,785 +And put a thumbnail that it found in the GPX file for + +38 +00:01:59,787 --> 00:02:03,455 +each waypoint, okay? So now, what we'll do today, + +39 +00:02:03,457 --> 00:02:06,024 +the next thing we're gonna do is learn how to segue from + +40 +00:02:06,026 --> 00:02:08,660 +a map, because it's a little unusual trying to segue from + +41 +00:02:08,662 --> 00:02:12,131 +a map because when you look at it in the storyboard it's + +42 +00:02:12,133 --> 00:02:13,899 +just blank, this big blank map view, + +43 +00:02:13,901 --> 00:02:15,868 +so that you can't, it's not like a table view where you + +44 +00:02:15,870 --> 00:02:18,670 +got a row you can Ctrl+drag from or something. So + +45 +00:02:18,672 --> 00:02:21,540 +we're gonna have to do this segueing from a map in code. + +46 +00:02:21,542 --> 00:02:23,809 +And what we're gonna do is make it so that when we + +47 +00:02:23,811 --> 00:02:27,079 +click on this little thumbnail button right here, it segues, + +48 +00:02:27,081 --> 00:02:31,083 +okay. And puts an image view controller that will show you + +49 +00:02:31,085 --> 00:02:36,088 +the full large image of this. And we're gonna get the UI for + +50 +00:02:36,090 --> 00:02:36,455 +doing that imagery control, + +51 +00:02:36,457 --> 00:02:38,357 +we're just gonna steal that right out of Cassini. I mean, + +52 +00:02:38,359 --> 00:02:41,026 +you're gonna see the advantage of building these MVCs that + +53 +00:02:41,028 --> 00:02:44,530 +have very clear public models. It makes them quite reuseable. + +54 +00:02:44,532 --> 00:02:47,833 +So we can reuse that MVC we made in Cassini with + +55 +00:02:47,835 --> 00:02:50,235 +absolutely no changes. Gonna just drag it in and + +56 +00:02:50,237 --> 00:02:53,205 +set up its public API and it'll work perfectly. So + +57 +00:02:53,207 --> 00:02:56,441 +let's go do that right now, let's go over to Cassini. + +58 +00:02:56,443 --> 00:03:02,147 +And where is Cassini? It's here in Developer > Cassini. + +59 +00:03:02,149 --> 00:03:04,683 +We open Cassi, Cassini here. So remember, you'll + +60 +00:03:04,685 --> 00:03:07,853 +remember Cassini here. And we, it's the one that showed the, + +61 +00:03:07,855 --> 00:03:10,155 +the image of Cassini, what it was doing. So + +62 +00:03:10,157 --> 00:03:12,457 +I'm just gonna grab this ImageViewController, + +63 +00:03:12,459 --> 00:03:15,127 +right here, this class ImageViewController. And + +64 +00:03:15,129 --> 00:03:18,664 +I'm gonna pick it up and drag it into my app over here and + +65 +00:03:18,666 --> 00:03:22,034 +I'm gonna copy it in, okay? But I can do actually more + +66 +00:03:22,036 --> 00:03:24,169 +than that, more than just grabbing that MVC, + +67 +00:03:24,171 --> 00:03:26,738 +I can actually go to the storyboard and find the place + +68 +00:03:26,740 --> 00:03:29,441 +in the storyboard, down here actually, where Casini is + +69 +00:03:29,443 --> 00:03:33,512 +using the ImageViewController. And I can copy that scene from + +70 +00:03:33,514 --> 00:03:39,184 +Casini and then bring it on over to our storyboard here. + +71 +00:03:39,186 --> 00:03:43,589 +We'll zoom out so you can see this. Okay, and we can paste. + +72 +00:03:43,591 --> 00:03:46,024 +And that actually dropped an ImageViewController there, + +73 +00:03:46,026 --> 00:03:49,328 +with the scroll view already in it and wired up. And + +74 +00:03:49,330 --> 00:03:52,364 +it has the proper identity, right, ImageViewController, so + +75 +00:03:52,366 --> 00:03:55,367 +it's all really nice. So don't forget that, in storyboards + +76 +00:03:55,369 --> 00:03:58,170 +you can copy and paste scenes between storyboards and + +77 +00:03:58,172 --> 00:03:58,604 +it'll bring it all. + +78 +00:03:58,606 --> 00:04:00,439 +And it brings it all by name, remember, so + +79 +00:04:00,441 --> 00:04:02,441 +you have to have the classes with the same name or + +80 +00:04:02,443 --> 00:04:07,012 +outlets with the same name for it all to work. Okay, so let's + +81 +00:04:07,014 --> 00:04:10,649 +go ahead and build the rest of our UI that we have here. + +82 +00:04:10,651 --> 00:04:14,186 +We want to segue from this map view over to this scroll + +83 +00:04:14,188 --> 00:04:17,322 +view, but we don't really anything to Ctrl+drag from + +84 +00:04:17,324 --> 00:04:20,092 +here cuz of the callouts and things like that are all come + +85 +00:04:20,094 --> 00:04:22,995 +up from programmatically. So we're gonna do a manual + +86 +00:04:22,997 --> 00:04:25,631 +segue, which we've already seen and the way we do that is + +87 +00:04:25,633 --> 00:04:28,433 +we Ctrl+drag from the View Controller itself just to + +88 +00:04:28,435 --> 00:04:31,370 +create a segue with a certain identifier, okay, between + +89 +00:04:31,372 --> 00:04:36,074 +the two MVCs. So let's just get these both on screen here. + +90 +00:04:36,076 --> 00:04:39,578 +And I'm gonna Ctrl+drag from here over to here. + +91 +00:04:39,580 --> 00:04:41,780 +We're gonna put this inside the navigation controller. + +92 +00:04:41,782 --> 00:04:45,083 +So this is gonna be a show segue right here. + +93 +00:04:45,085 --> 00:04:48,620 +And we'll give it a name. This is gonna show an image, so + +94 +00:04:48,622 --> 00:04:51,957 +we'll call this Show Image segue. Let's be sure to go + +95 +00:04:51,959 --> 00:04:57,462 +ahead and embed this in a Navigation Controller. Okay, + +96 +00:04:57,464 --> 00:05:00,899 +oops, so let's zoom out and take a look at our UI. So + +97 +00:05:00,901 --> 00:05:03,735 +here's our UI. We could even do some other things like here + +98 +00:05:03,737 --> 00:05:06,505 +I'd maybe this, we wanna give it a title, we'll call it + +99 +00:05:06,507 --> 00:05:09,541 +Trax, or something like that. And this title we'll set + +100 +00:05:09,543 --> 00:05:11,943 +programmatically depending on which waypoint we're + +101 +00:05:11,945 --> 00:05:15,447 +looking at, we'll put whatever the name of that waypoint is + +102 +00:05:15,449 --> 00:05:15,714 +so we'll do that in the code. All right, so how are we gonna + +103 +00:05:15,716 --> 00:05:20,052 +in at the top, + +104 +00:05:20,054 --> 00:05:23,455 +fire off this segue right here from the code? + +105 +00:05:23,457 --> 00:05:24,823 +Where's a good place to do it in the code? Well, + +106 +00:05:24,825 --> 00:05:29,728 +we know we wanna do it when we click on that left accessory + +107 +00:05:29,730 --> 00:05:32,764 +view button right there. And if you'll remember from + +108 +00:05:32,766 --> 00:05:36,702 +lecture, there's a really cool map view, MKMapViewDelegate + +109 +00:05:36,704 --> 00:05:39,571 +method, I'm just back here in GPXViewController + +110 +00:05:39,573 --> 00:05:42,174 +here. So this is a really cool MapViewDelegate method + +111 +00:05:42,176 --> 00:05:45,844 +that will get called when an accessory view is tapped on + +112 +00:05:45,846 --> 00:05:48,513 +and that accessory view is a UI control like + +113 +00:05:48,515 --> 00:05:51,249 +a UI button, for example. All right, so let's put that in + +114 +00:05:51,251 --> 00:05:54,986 +here. That thing is called a callout accessory, there it + +115 +00:05:54,988 --> 00:06:00,258 +is, MapView, annotationView, calloutAccessory view Tapped, + +116 +00:06:00,260 --> 00:06:02,961 +okay? Let's give ourselves a lot more room here. + +117 +00:06:02,963 --> 00:06:06,331 +This is this method. And all we need to do here is look at + +118 +00:06:06,333 --> 00:06:09,368 +the control that was tapped, and see if it's our left + +119 +00:06:09,370 --> 00:06:13,105 +AccessoryView, okay? So if the control == our views, + +120 +00:06:13,107 --> 00:06:17,609 +leftCalloutAccessoryView, okay, then we know someone + +121 +00:06:17,611 --> 00:06:21,580 +tapped on that left side. And we wanna do this segue, and + +122 +00:06:21,582 --> 00:06:24,383 +we know how to perform a segue from clo, from code. + +123 +00:06:24,385 --> 00:06:27,686 +We just do performSegueWithIdentifier. + +124 +00:06:27,688 --> 00:06:30,288 +Okay, the identifier is that "Show Image", I actually + +125 +00:06:30,290 --> 00:06:32,691 +created a constant for that right here, okay just so + +126 +00:06:32,693 --> 00:06:37,863 +my code would be nice. So constants.ShowImageSegue. + +127 +00:06:37,865 --> 00:06:40,766 +And what about the sender? Well, when this segue happens, + +128 +00:06:40,768 --> 00:06:44,236 +we're gonna need to know which of our many waypoints we wanna + +129 +00:06:44,238 --> 00:06:47,973 +show the image of, okay. So we need to pass a sender on + +130 +00:06:47,975 --> 00:06:50,809 +to prepareForSegue that can identify it. + +131 +00:06:50,811 --> 00:06:53,945 +And a simple thing to do here, okay, this argument + +132 +00:06:53,947 --> 00:06:57,282 +that we get right here is the annotationView. Okay, + +133 +00:06:57,284 --> 00:07:01,286 +that was, that this callout has a left accessory view + +134 +00:07:01,288 --> 00:07:02,554 +for, so we'll just pass that along. + +135 +00:07:02,556 --> 00:07:05,090 +So we'll just pass that as the sender, which makes sense, + +136 +00:07:05,092 --> 00:07:05,991 +the annotationView is the sender. + +137 +00:07:05,993 --> 00:07:08,727 +And from the annotationView, we're gonna be able to get + +138 +00:07:08,729 --> 00:07:11,463 +the waypoint that we want. Okay, so that couldn't + +139 +00:07:11,465 --> 00:07:15,300 +be simpler right there. Now what about the navigation? So + +140 +00:07:15,302 --> 00:07:18,103 +let's put in some navigation here, the prepareForSegue. + +141 +00:07:18,105 --> 00:07:20,372 +Because any segue needs to be prepared. In this case, + +142 +00:07:20,374 --> 00:07:23,608 +we're going to have to prepare that ImageViewController with + +143 +00:07:23,610 --> 00:07:25,610 +its public API, which, if you'll remember, + +144 +00:07:25,612 --> 00:07:29,247 +is an image URL. We have to give it the URL of an image, + +145 +00:07:29,249 --> 00:07:32,150 +okay? So prepareForSegue, let's do that, + +146 +00:07:32,152 --> 00:07:36,288 +prepareForSegue. And what do we need for prepareForSegue? + +147 +00:07:36,290 --> 00:07:38,623 +Well, first of all, let's collect some information here, + +148 +00:07:38,625 --> 00:07:40,525 +like, let's get the destinationViewController. + +149 +00:07:40,527 --> 00:07:43,762 +That's the segue's destinationViewController. + +150 +00:07:43,764 --> 00:07:47,165 +And actually, I'm gonna do that contentViewController + +151 +00:07:47,167 --> 00:07:50,802 +trick that we did where we have a little extension, + +152 +00:07:50,804 --> 00:07:52,437 +contentViewController here, + +153 +00:07:52,439 --> 00:07:54,739 +a little extension to UIViewController. + +154 +00:07:54,741 --> 00:07:57,108 +So that if the thing is in a Navigation Controller, + +155 +00:07:57,110 --> 00:07:58,443 +we return the visibleViewController, + +156 +00:07:58,445 --> 00:08:01,112 +otherwise we just return self. You remember this from From + +157 +00:08:01,114 --> 00:08:03,648 +before, this is so that if we're in a split view and + +158 +00:08:03,650 --> 00:08:05,717 +we happen to put the detail, for example, + +159 +00:08:05,719 --> 00:08:06,985 +inside a navigation controller, + +160 +00:08:06,987 --> 00:08:09,955 +we can get the thing that's inside. All right, so + +161 +00:08:09,957 --> 00:08:13,625 +we'll do the content view controller. Here, so + +162 +00:08:13,627 --> 00:08:17,195 +that's the destination of, this, segue. + +163 +00:08:17,197 --> 00:08:19,931 +Let's get the annotation view, which is the sender, + +164 +00:08:19,933 --> 00:08:23,301 +okay this sender any object, should be an annotation view, + +165 +00:08:23,303 --> 00:08:24,469 +so let's go ahead and get that. + +166 +00:08:24,471 --> 00:08:29,541 +By saying the sender as an MKAnnotationView. Okay. + +167 +00:08:29,543 --> 00:08:33,078 +Let's also get the waypoint that we're talking about here. + +168 +00:08:33,080 --> 00:08:35,981 +Okay, all these segues are gonna be segueing from + +169 +00:08:35,983 --> 00:08:38,517 +something that has a waypoint. So what is that? + +170 +00:08:38,519 --> 00:08:43,355 +That's gonna be the annotationViews annotation. + +171 +00:08:43,557 --> 00:08:45,924 +And it has to be a gpx waypoint, which they all + +172 +00:08:45,926 --> 00:08:50,028 +should be. All the annotations that we add to our map view + +173 +00:08:50,030 --> 00:08:53,665 +implement the MK protocol, so they're all gpx waypoint. + +174 +00:08:53,667 --> 00:08:55,667 +So this should always come out true. + +175 +00:08:55,669 --> 00:08:58,537 +So we kinda got these little things that we need. + +176 +00:08:58,539 --> 00:09:03,241 +So now lets just say if the segway identifier equals + +177 +00:09:03,243 --> 00:09:08,079 +the Constants.ShowSegue, ShowImageSegue, okay? + +178 +00:09:08,081 --> 00:09:11,850 +So we know we're going the show image. Then if we can get + +179 +00:09:11,852 --> 00:09:14,886 +an ImageViewController as the destination, so + +180 +00:09:14,888 --> 00:09:18,290 +if the destination is an ImageViewController, + +181 +00:09:18,525 --> 00:09:23,028 +then we can just load it up by saying it's imageURL equals + +182 +00:09:23,030 --> 00:09:24,829 +the waypoints. + +183 +00:09:25,766 --> 00:09:29,301 +Image URL, right remember image URL, + +184 +00:09:29,303 --> 00:09:32,671 +we added that when we put this little extension on here that + +185 +00:09:32,673 --> 00:09:36,107 +did the thumbnail URL we also added the image URL. Its just + +186 +00:09:36,109 --> 00:09:40,045 +gonna look in the gpx file information to find an image + +187 +00:09:40,047 --> 00:09:44,282 +url that's got the type large verse the type thumbnail. + +188 +00:09:44,284 --> 00:09:46,885 +Okay? Cuz we obviously wanna show the large image, + +189 +00:09:46,887 --> 00:09:50,522 +when we segue to it. All right? All right, so + +190 +00:09:50,524 --> 00:09:52,290 +that's good. While we're here, let's go ahead and + +191 +00:09:52,292 --> 00:09:57,662 +set the title of this, thing to be the waypoint's name. So + +192 +00:09:57,664 --> 00:10:00,031 +that'll give us a nice title at the top, + +193 +00:10:00,033 --> 00:10:06,571 +of our MVC. Okay? Makes sense? All right so + +194 +00:10:06,573 --> 00:10:11,476 +let's go to run see what this does. See if it works for us? + +195 +00:10:17,017 --> 00:10:20,218 +All right, so here is all of our little waypoints here. So + +196 +00:10:20,220 --> 00:10:24,422 +let's click on waypoint, like this one, still working okay, + +197 +00:10:24,424 --> 00:10:26,524 +we got the picture in here but now hopefully if we click on + +198 +00:10:26,526 --> 00:10:30,729 +this, we'll seque. Sure enough here we go. My image view + +199 +00:10:30,731 --> 00:10:32,130 +controller is not quite as nice as the one you did in + +200 +00:10:32,132 --> 00:10:35,233 +your homework in terms of the white space management but + +201 +00:10:35,235 --> 00:10:37,636 +it works. Notice it's got the title up here as well. + +202 +00:10:37,638 --> 00:10:39,471 +The title of this thing, Panorama, + +203 +00:10:39,473 --> 00:10:45,377 +got passed along there. Okay, so that was pretty easy. + +204 +00:10:45,746 --> 00:10:47,679 +The next thing we're gonna do is make it so + +205 +00:10:47,681 --> 00:10:51,816 +that in our map here, we can add a waypoint. + +206 +00:10:51,818 --> 00:10:54,719 +Now, this is a demo, I'm not gonna go so far as to actually + +207 +00:10:54,721 --> 00:10:58,356 +rewrite the gpx file to add this waypoint to it, but I'm + +208 +00:10:58,358 --> 00:11:02,260 +gonna show you how to at least add the waypoint to the map. + +209 +00:11:02,262 --> 00:11:05,563 +Now, the UI I'm gonna use here is long press. + +210 +00:11:05,565 --> 00:11:08,166 +I don't know if you've seen a long press gesture, but + +211 +00:11:08,168 --> 00:11:10,368 +basically if you just press with your finger and + +212 +00:11:10,370 --> 00:11:11,169 +you hold it down long enough, + +213 +00:11:11,171 --> 00:11:14,839 +it'll start looking like a long press, to iOS. + +214 +00:11:14,841 --> 00:11:17,442 +And when you long press, I'm gonna drop another pin there. + +215 +00:11:17,444 --> 00:11:21,780 +A new pin. It's gonna be a new we, new waypoint. All right so + +216 +00:11:21,782 --> 00:11:23,348 +let's put that in our UI first, + +217 +00:11:23,350 --> 00:11:26,851 +let's go, back here to our story board and + +218 +00:11:26,853 --> 00:11:30,221 +we're just gonna add a long press gesture to this map, so + +219 +00:11:30,223 --> 00:11:34,092 +i'm gonna go over here down to this, I'll even search for it + +220 +00:11:34,094 --> 00:11:36,594 +and make it even easier, long press. Here it is right here, + +221 +00:11:36,596 --> 00:11:39,497 +so I'm gonna add this long press the map view is the one + +222 +00:11:39,499 --> 00:11:44,102 +that is gonna recognize it right there, to it. + +223 +00:11:44,104 --> 00:11:48,373 +And now we're go ahead and make this long press send + +224 +00:11:48,375 --> 00:11:51,009 +action to our con, view controller. So let's get them + +225 +00:11:51,011 --> 00:11:55,780 +on the screen at the same time here. All right go automatic. + +226 +00:11:56,049 --> 00:12:01,119 +Okay we'll put it let's put it right down here. Okay? So + +227 +00:12:01,121 --> 00:12:03,755 +I'm just gonna Ctrl+drag from the long press gesture + +228 +00:12:03,757 --> 00:12:07,792 +into here. Its going to be an action, we will call this Add + +229 +00:12:07,794 --> 00:12:10,829 +wayPoint because that is what this gesture is going to do, + +230 +00:12:10,831 --> 00:12:15,166 +its going to add a waypoint. OK, lets go ahead and + +231 +00:12:15,168 --> 00:12:19,871 +go back here. All right, so we have got Add waypoint right + +232 +00:12:19,873 --> 00:12:22,674 +here. What do we need to do when we add a waypoint? + +233 +00:12:22,676 --> 00:12:27,712 +Well, first we're going to do it as soon as we + +234 +00:12:27,714 --> 00:12:32,484 +recognize the long press. So soon as it + +235 +00:12:32,486 --> 00:12:35,019 +starts recognizing this long press, we're going to do it. + +236 +00:12:35,021 --> 00:12:37,622 +Now a long press is actually a continuous gesture. + +237 +00:12:37,624 --> 00:12:39,157 +If you hold the long town press down, + +238 +00:12:39,159 --> 00:12:41,693 +it'll keep firing. Okay fire over and over and + +239 +00:12:41,695 --> 00:12:43,027 +over. We don't want that we don't want to add + +240 +00:12:43,029 --> 00:12:44,662 +a whole bunch of waypoints we just want the first one. + +241 +00:12:44,664 --> 00:12:46,898 +So as soon as we recognize that it's a long press + +242 +00:12:46,900 --> 00:12:48,900 +we're gonna drop the waypoint and we don't care what happens + +243 +00:12:48,902 --> 00:12:52,637 +with the press after that we're ignoring. Okay? + +244 +00:12:52,639 --> 00:12:54,472 +So we've got to get the coordinate + +245 +00:12:54,474 --> 00:12:57,408 +okay that CL coordinate 2d right the latitude and + +246 +00:12:57,410 --> 00:13:01,246 +longitude of this thing that's dropped. And to do that, + +247 +00:13:01,248 --> 00:13:03,648 +we're gonna have to take the coordinate from the gesture, + +248 +00:13:03,650 --> 00:13:06,751 +which is a view coordinate, and turn it into longitude and + +249 +00:13:06,753 --> 00:13:09,621 +latitude. Well luckily Mapview knows how to do that, + +250 +00:13:09,623 --> 00:13:13,024 +Mapview has a method called convertPoint, + +251 +00:13:13,026 --> 00:13:14,793 +two coordinate from view, you see it right there, + +252 +00:13:14,795 --> 00:13:17,762 +the first one, Convert point to coordinate from view. So + +253 +00:13:17,764 --> 00:13:22,767 +the point it wants to convert is the gesture recognizers + +254 +00:13:22,769 --> 00:13:27,172 +location in view, okay. And what view? + +255 +00:13:27,174 --> 00:13:28,373 +The map view itself. So + +256 +00:13:28,375 --> 00:13:30,708 +we're gonna get the location to gesture in the map view and + +257 +00:13:30,710 --> 00:13:34,712 +we're going to turn it into a coordinate and the coordinates + +258 +00:13:34,714 --> 00:13:40,084 +we're, converting from is the map view also. Okay. + +259 +00:13:40,086 --> 00:13:43,454 +So now we've got the latitude and longitude that the long + +260 +00:13:43,456 --> 00:13:46,457 +press happened at. So now let's create a wave point, and + +261 +00:13:46,459 --> 00:13:50,628 +we're going to do that by just saying GPX.wavepoint, latitude + +262 +00:13:50,630 --> 00:13:53,832 +and longitude. Right? So the latitude is the coordinates + +263 +00:13:53,834 --> 00:13:59,304 +latitude, and longitude is the coordinates longitude. Right? + +264 +00:13:59,306 --> 00:13:59,704 +This coordinate right here, + +265 +00:13:59,706 --> 00:14:02,807 +that's this coordinate we just created. All right. So we got + +266 +00:14:02,809 --> 00:14:06,211 +a waypoint and we can give the waypoint a name, let's give it + +267 +00:14:06,213 --> 00:14:08,847 +a default name. We'll call it Dropped since we just dropped + +268 +00:14:08,849 --> 00:14:12,417 +this waypoint onto of the map. Now let's go and add that as + +269 +00:14:12,419 --> 00:14:17,355 +an annotation, to the map, and we know that this is legal for + +270 +00:14:17,357 --> 00:14:21,025 +us to do because addAnnotation takes an MKAnnotation and + +271 +00:14:21,027 --> 00:14:22,160 +we know that GPS. Way, + +272 +00:14:22,162 --> 00:14:25,230 +GPX.Waypoint implements the MKAnnotation protocol, so + +273 +00:14:25,232 --> 00:14:29,868 +this is perfectly legal for us to do, right? All right, so + +274 +00:14:29,870 --> 00:14:37,542 +let's go take a look see if this works. All right, + +275 +00:14:37,544 --> 00:14:40,645 +so here we are. I'm just going to let's say right up here is + +276 +00:14:40,647 --> 00:14:43,514 +a little airport here, so let's hold it down and + +277 +00:14:43,516 --> 00:14:45,216 +drop and sure enough, it dropped a pin there, okay. + +278 +00:14:45,218 --> 00:14:48,219 +We drop another one over here, another one over here. Now, + +279 +00:14:48,221 --> 00:14:51,923 +if I click on this, I'm just gonna get dropped. Okay? + +280 +00:14:51,925 --> 00:14:54,425 +Also, what if I put this in the wrong spot and + +281 +00:14:54,427 --> 00:14:57,061 +I wanted to pick it up? 'Kay, there's no way to pick it up + +282 +00:14:57,063 --> 00:15:02,100 +and move it and that's because these pins are not "dragable." + +283 +00:15:02,102 --> 00:15:04,669 +And if you remember from the, la a, slides, + +284 +00:15:04,671 --> 00:15:07,438 +to make a pin dragable you have to take that coordinate, + +285 +00:15:07,440 --> 00:15:10,608 +ma, var, you know we have this coordinate var that we added + +286 +00:15:10,610 --> 00:15:13,912 +when we were implementing MKannotation we added this. + +287 +00:15:13,914 --> 00:15:16,948 +This has to be read and write. To make these things + +288 +00:15:16,950 --> 00:15:19,183 +obviously dragable if they're going to be dragable when they + +289 +00:15:19,185 --> 00:15:21,653 +drop into a new place we need to set the new coordinates. + +290 +00:15:21,655 --> 00:15:24,722 +So we need to have a editable or + +291 +00:15:24,724 --> 00:15:27,225 +one of these that has a get and a set. So + +292 +00:15:27,227 --> 00:15:30,995 +I'm actually going to do that by creating a subclass of + +293 +00:15:30,997 --> 00:15:36,601 +GPX Waypoint called editable ed it a ble waypoint, + +294 +00:15:36,603 --> 00:15:40,905 +okay. It's just gonna sub class GPX.waypoint and + +295 +00:15:40,907 --> 00:15:43,508 +in that sub class I'm gonna make coordinate. + +296 +00:15:43,510 --> 00:15:48,680 +B read right VAR. So coordinate, CL location, + +297 +00:15:48,682 --> 00:15:50,882 +coordinate 2D is gonna have a get and + +298 +00:15:50,884 --> 00:15:54,152 +it's also gonna have the set. Now for the get, I'm just + +299 +00:15:54,154 --> 00:15:58,022 +gonna do super. coordinate. Okay? We should note + +300 +00:15:58,024 --> 00:16:02,527 +that we are overriding this bar from gpx waypoint, okay. + +301 +00:16:02,529 --> 00:16:05,830 +And for the set, we've got this new value which is + +302 +00:16:05,832 --> 00:16:09,400 +a coordinate and I need to put that into the GPXs data + +303 +00:16:09,402 --> 00:16:13,137 +structure which is latitude and longitude right? + +304 +00:16:13,139 --> 00:16:15,807 +So, I'm just gonna say here that, + +305 +00:16:15,809 --> 00:16:19,978 +our latitude equals the new value's latitude and + +306 +00:16:19,980 --> 00:16:24,082 +our longitude equals the new value's longitude. + +307 +00:16:24,084 --> 00:16:27,585 +Okay, so we're setting the latitude and the longitude in + +308 +00:16:27,587 --> 00:16:31,622 +the GPX waypoint from this new coordinate value that we got. + +309 +00:16:31,624 --> 00:16:35,526 +Okay. So, we'll do that. Everybody get that. + +310 +00:16:35,528 --> 00:16:36,627 +Everyone understand what I what I did there? + +311 +00:16:36,629 --> 00:16:38,930 +So, I have this new class now, EditableWaypoint. + +312 +00:16:38,932 --> 00:16:41,165 +Yeah, I probably could have done that here, + +313 +00:16:41,167 --> 00:16:44,002 +put in the extension but it's actually nice as you're + +314 +00:16:44,004 --> 00:16:46,771 +gonna see to have a whole class that we know that this + +315 +00:16:46,773 --> 00:16:49,140 +is an editable waypoint by looking at its class, + +316 +00:16:49,142 --> 00:16:53,745 +actually. All right? Okay, so let's go back now to here, and + +317 +00:16:53,747 --> 00:16:57,148 +instead of creating a GPX waypoint here now when we add + +318 +00:16:57,150 --> 00:17:02,086 +waypoint, I'm gonna create an editable waypoint. Okay. + +319 +00:17:02,088 --> 00:17:04,389 +So that, so that it can be moved around. + +320 +00:17:04,391 --> 00:17:07,892 +Now, the other thing I need to do to make it an draggable + +321 +00:17:07,894 --> 00:17:11,629 +is to go here to where I create my annotation view for + +322 +00:17:11,631 --> 00:17:13,131 +annotation which remember, + +323 +00:17:13,133 --> 00:17:15,900 +is kind of self row index path for map view. + +324 +00:17:15,902 --> 00:17:17,602 +Here's where I create the left call it accessory. + +325 +00:17:17,604 --> 00:17:21,806 +I also need to say whether it's draggable. Okay? + +326 +00:17:21,808 --> 00:17:25,643 +And that's just going to be, whether or not the annotation + +327 +00:17:25,645 --> 00:17:29,647 +that we passed on here is an editable waypoint. Okay? + +328 +00:17:29,649 --> 00:17:31,783 +If annotation is of class editable waypoint, + +329 +00:17:31,785 --> 00:17:34,352 +then we know it's editable, and so it's dragable. + +330 +00:17:34,354 --> 00:17:37,188 +See how giving that in a separate class was kind of + +331 +00:17:37,190 --> 00:17:39,724 +cool? Makes our code read kind of nice there. + +332 +00:17:39,726 --> 00:17:42,527 +All right, so we should be able to drag this around, so + +333 +00:17:42,529 --> 00:17:49,801 +let's see if it works. All right, + +334 +00:17:49,803 --> 00:17:51,836 +so you going to drop one right here, here it is, + +335 +00:17:51,838 --> 00:17:54,338 +we can see this is dropped. Can we pick it up and drag it? + +336 +00:17:54,340 --> 00:17:59,377 +Let's see. Yes, we can put it somewhere else pick it + +337 +00:17:59,379 --> 00:18:02,947 +up again put it over here. Okay so + +338 +00:18:02,949 --> 00:18:06,050 +that's kind of cool. So, now what are we gonna do? Well, + +339 +00:18:06,052 --> 00:18:09,353 +it's kind of annoying that this just says dropped, okay. + +340 +00:18:09,355 --> 00:18:10,788 +We don't want it to say dropped, + +341 +00:18:10,790 --> 00:18:11,923 +we wanna actually edit it and so, + +342 +00:18:11,925 --> 00:18:13,891 +you know if I put it over here on top of this little + +343 +00:18:13,893 --> 00:18:17,328 +airport right here, I probably wanna put airport in there. + +344 +00:18:17,330 --> 00:18:20,431 +Okay? And so how are we gonna do that? Well, + +345 +00:18:20,433 --> 00:18:23,334 +this is a good opportunity to show you a modal segue. + +346 +00:18:23,336 --> 00:18:27,138 +Okay, cuz what we're gonna do is we're gonna create a little + +347 +00:18:27,140 --> 00:18:29,807 +MVC to edit the name and the description there of + +348 +00:18:29,809 --> 00:18:33,244 +the waypoint and we're going to modally present that MVC, + +349 +00:18:33,246 --> 00:18:37,448 +okay? So, how we're gonna do that? Pretty straightforward. + +350 +00:18:37,450 --> 00:18:40,985 +Let's start here by figuring out how we're gonna get + +351 +00:18:40,987 --> 00:18:42,120 +that modal MVC to appear and + +352 +00:18:42,122 --> 00:18:44,956 +what I'm gonna do is you see how I'm using over here + +353 +00:18:44,958 --> 00:18:48,326 +at the left accessory view. Now, I'm gonna use the right + +354 +00:18:48,328 --> 00:18:50,928 +accessory view on these and I'm gonna put a detail + +355 +00:18:50,930 --> 00:18:54,132 +disclosure button in there. That's the little blue kinda + +356 +00:18:54,134 --> 00:18:57,101 +looks like a blue round circle with a carrot in it. So, + +357 +00:18:57,103 --> 00:18:59,804 +I'm gonna put that kind of button in here and only on + +358 +00:18:59,806 --> 00:19:02,173 +that editable way points will I put it there. And + +359 +00:19:02,175 --> 00:19:05,309 +when you click on that, it's going to bring up this modal + +360 +00:19:05,311 --> 00:19:09,714 +panel that lets you edit the name and info. Okay. So, let's + +361 +00:19:09,716 --> 00:19:15,219 +go ahead and do that, let's change our UI to make our UI, + +362 +00:19:15,221 --> 00:19:17,822 +that's how we gonna do that. + +363 +00:19:17,824 --> 00:19:20,358 +We're gonna have to add a RightCalloutAccessoryView. + +364 +00:19:20,360 --> 00:19:22,760 +Just like we added a leftCalloutAccessoryView here, + +365 +00:19:22,762 --> 00:19:25,329 +so I'm gonna do the same thing where I clear it out first + +366 +00:19:25,331 --> 00:19:27,698 +because if it's not at an editable waypoint we don't + +367 +00:19:27,700 --> 00:19:30,301 +want it in there. And remember we're reusing these things, + +368 +00:19:30,303 --> 00:19:33,538 +right? DQ reusable. So, we have to clear it out from + +369 +00:19:33,540 --> 00:19:37,141 +previous uses. And so, here I'm just gonna say, + +370 +00:19:37,143 --> 00:19:41,479 +if the waypoint is an EditableWaypoint,then I need + +371 +00:19:41,481 --> 00:19:46,017 +to add this rightCallout AccessoryView which is just + +372 +00:19:46,019 --> 00:19:51,022 +going to be a UIButton(type: .DetailDisclosure). + +373 +00:19:51,024 --> 00:19:51,923 +Okay, so I'm just going to put it on. + +374 +00:19:51,925 --> 00:19:54,792 +This is only going to appear on editable ones which is + +375 +00:19:54,794 --> 00:19:58,196 +exactly what we want. Now, how do we make it so that it's + +376 +00:19:58,198 --> 00:20:01,866 +going to Do this modal segue whenever we're gonna do it. + +377 +00:20:01,868 --> 00:20:03,801 +We're gonna do the exact same way that we did for + +378 +00:20:03,803 --> 00:20:06,637 +the left call-out accessory, which is what we're gonna do + +379 +00:20:06,639 --> 00:20:08,639 +it in this call-out accessory control tapped. + +380 +00:20:08,641 --> 00:20:11,375 +Okay, cuz now this the right side one. So, I'm gonna say + +381 +00:20:11,377 --> 00:20:15,813 +else if the control equals the right call-out accessory view. + +382 +00:20:15,815 --> 00:20:21,552 +Okay? Then, I need to perform a segue, the different one. + +383 +00:20:22,121 --> 00:20:25,756 +This one's gonna be called, let's see what I call down + +384 +00:20:25,758 --> 00:20:28,759 +here in the constance. I call it edit way points, + +385 +00:20:28,761 --> 00:20:32,830 +the Edit user way points segway, right? Edit user way + +386 +00:20:32,832 --> 00:20:36,000 +points and the sender still gonna be the view because we + +387 +00:20:36,002 --> 00:20:39,003 +still wanna know which way point we're editing, okay? And + +388 +00:20:39,005 --> 00:20:42,540 +of course, we have to fix or prepare for segway to do that + +389 +00:20:42,542 --> 00:20:47,311 +as well. Let's take a time out from doing our prepare for + +390 +00:20:47,313 --> 00:20:51,315 +segue and go into our storyboard and add that new + +391 +00:20:51,317 --> 00:20:54,552 +MVC. All right, so here we are, I'm going to make this + +392 +00:20:54,554 --> 00:20:56,053 +a little zoomed out a little bit. So, + +393 +00:20:56,055 --> 00:20:58,823 +I'm going to put this new view controller just by dragging + +394 +00:20:58,825 --> 00:21:01,158 +out an empty view controller on to the top up here. + +395 +00:21:01,160 --> 00:21:02,226 +This is where we're going to put this thing. + +396 +00:21:02,228 --> 00:21:05,896 +It's of course, going to need it's own Custom Class so lets + +397 +00:21:05,898 --> 00:21:10,635 +go file New. Create a subclass of UI View Controller. Okay. + +398 +00:21:10,637 --> 00:21:13,371 +We'll call this our Edit Waypoint View Controller + +399 +00:21:13,373 --> 00:21:16,674 +because that's what it does. Edit a waypoint. + +400 +00:21:16,676 --> 00:21:19,343 +I'll put it same place as everything as usual. + +401 +00:21:19,345 --> 00:21:22,980 +Here it is, we'll go ahead and get rid of all this stuff. + +402 +00:21:23,950 --> 00:21:26,484 +Yeah, so that's clean. Let's go ahead and build the ui of + +403 +00:21:26,486 --> 00:21:30,321 +it, okay what's the ui of this thing gonna look like here? + +404 +00:21:30,323 --> 00:21:32,290 +Well, it's gonna be a pretty simple UI, + +405 +00:21:32,292 --> 00:21:33,591 +it's gonna have two fields, one for + +406 +00:21:33,593 --> 00:21:36,527 +the name of the waypoint and one for like the info, right, + +407 +00:21:36,529 --> 00:21:38,429 +the little description of the waypoint. So, + +408 +00:21:38,431 --> 00:21:41,565 +that's gonna be easy to build, let's just go down here and + +409 +00:21:41,567 --> 00:21:44,068 +grab a text field or two, there's one text field, + +410 +00:21:44,070 --> 00:21:47,471 +there's another one, let's grab a couple labels okay for + +411 +00:21:47,473 --> 00:21:50,141 +our name and description. So, all right so + +412 +00:21:50,143 --> 00:21:51,442 +this is the name of the waypoint. + +413 +00:21:51,444 --> 00:21:56,347 +This is the description of it which is called the info field + +414 +00:21:56,349 --> 00:22:00,084 +in the GPX structure. So, we'll right align these + +415 +00:22:00,086 --> 00:22:02,887 +because they're gonna be names. We'll go ahead and + +416 +00:22:02,889 --> 00:22:06,724 +put these in a stack view here. So, let's embed these in + +417 +00:22:06,726 --> 00:22:08,893 +a stack view. Hopefully it'll figure out it's horizontal. + +418 +00:22:08,895 --> 00:22:11,495 +It does. We'll put a little spacing in there, + +419 +00:22:11,497 --> 00:22:13,264 +maybe eight or something like that. + +420 +00:22:13,266 --> 00:22:16,534 +Same thing here, let's put those in. Okay. + +421 +00:22:16,536 --> 00:22:22,973 +Also, eight. Now, let's put these in vertical stack view. + +422 +00:22:26,079 --> 00:22:29,113 +Okay, maybe we'll also do 8 here as well. + +423 +00:22:29,115 --> 00:22:32,783 +Okay. Now, these aren't quite looking like what we want, + +424 +00:22:32,785 --> 00:22:35,152 +this, this kind of, this is in the center. + +425 +00:22:35,154 --> 00:22:37,421 +We don't really want center alignment here, + +426 +00:22:37,423 --> 00:22:39,490 +we'd like it to fill the entire space. Also, + +427 +00:22:39,492 --> 00:22:42,560 +we'd really want this and this lined up, which really means + +428 +00:22:42,562 --> 00:22:45,296 +we want Name and Description to be the same width. So, + +429 +00:22:45,298 --> 00:22:48,966 +I'm actually going to control drag between these two and + +430 +00:22:48,968 --> 00:22:52,069 +make them be equal widths, okay? Make name and + +431 +00:22:52,071 --> 00:22:55,973 +description be equal widths and also it's gonna, + +432 +00:22:55,975 --> 00:22:59,477 +let me take it back in a second here I think. + +433 +00:22:59,479 --> 00:23:00,911 +Let's also put it in position. + +434 +00:23:00,913 --> 00:23:05,282 +We're gonna put this leading edge, we're gonna put this + +435 +00:23:05,284 --> 00:23:09,253 +the top edge, we'll put this to the trailing edge and + +436 +00:23:09,255 --> 00:23:13,924 +we'll put this to the bottom edge. Okay? Now, where we + +437 +00:23:13,926 --> 00:23:17,995 +put these is a little weird. Okay, this one is our standard + +438 +00:23:17,997 --> 00:23:21,899 +thing here where we want this to be zero or standard value. + +439 +00:23:21,901 --> 00:23:23,701 +So, there's no standard value so we'll make it zero. + +440 +00:23:23,703 --> 00:23:27,138 +That makes it nice and wide. That's good. This one right + +441 +00:23:27,140 --> 00:23:30,374 +here, I actually don't want this one to be zero cuz + +442 +00:23:30,376 --> 00:23:33,244 +I really want name and description to sit at the top. + +443 +00:23:33,246 --> 00:23:35,746 +So, you might argue I don't even need a constraint on + +444 +00:23:35,748 --> 00:23:38,716 +the bottom here, but here's the thing when I put this + +445 +00:23:38,718 --> 00:23:41,952 +on screen, okay the size is gonna change I always wanna + +446 +00:23:41,954 --> 00:23:45,122 +make sure there's at least the standard issue thing from + +447 +00:23:45,124 --> 00:23:47,391 +the bottom. Get a standard space from the bottom and + +448 +00:23:47,393 --> 00:23:49,527 +you'll see why that is a little bit later. So, + +449 +00:23:49,529 --> 00:23:53,197 +I'm actually have the constant here be greater than or + +450 +00:23:53,199 --> 00:23:54,932 +equal to the standard value. Okay, + +451 +00:23:54,934 --> 00:23:57,535 +so just remember that I put a constraint on the bottom to + +452 +00:23:57,537 --> 00:24:00,971 +make sure it's greater than or equal to the standard value. + +453 +00:24:00,973 --> 00:24:03,641 +We we'll see that later. So, + +454 +00:24:03,643 --> 00:24:08,078 +equal widths. Thought I had done that. Okay, anyway, so + +455 +00:24:08,080 --> 00:24:12,850 +this looks pretty good for our UI, okay? Using the space, + +456 +00:24:12,852 --> 00:24:15,853 +etc. It's kind of lining things up nicely. So + +457 +00:24:15,855 --> 00:24:18,456 +let's go ahead and create a couple of outlets to pl, + +458 +00:24:18,458 --> 00:24:23,494 +plug into these two things, all right. Let's + +459 +00:24:23,496 --> 00:24:26,730 +make sure we set the right class for this. We don't want + +460 +00:24:26,732 --> 00:24:29,567 +to be in GPS Waypoint view controller, we wanted to be in + +461 +00:24:29,569 --> 00:24:32,536 +Edit Waypoint view controller. That's why we're not getting + +462 +00:24:32,538 --> 00:24:36,240 +the right class here when we try to do our list. + +463 +00:24:36,242 --> 00:24:37,575 +Let us drag our outlay here. + +464 +00:24:37,577 --> 00:24:41,979 +This outlay is going to be NameTextField. And + +465 +00:24:41,981 --> 00:24:47,017 +this one is going to be, call this the infoTextField. + +466 +00:24:47,854 --> 00:24:53,457 +All right? And so we kinda set up our UI here how we want it. + +467 +00:24:53,459 --> 00:24:58,128 +What do we wanna do here in terms of a let's + +468 +00:24:58,130 --> 00:25:01,932 +make this over here. Let's look at our edit wave. + +469 +00:25:01,934 --> 00:25:05,402 +Okay, what do we want to do in terms of a public model here, + +470 +00:25:05,404 --> 00:25:05,703 +so that people can set it? + +471 +00:25:05,705 --> 00:25:09,507 +Well, that's obvious, we want the a- waypoint to edit. 'Kay? + +472 +00:25:09,509 --> 00:25:14,478 +GPX, sorry, editable waypoint. Let it be optional. + +473 +00:25:14,480 --> 00:25:17,214 +So that's the public API. If someone sets this waypoint + +474 +00:25:17,216 --> 00:25:20,017 +then obviously we're going to have our UI show it. And when + +475 +00:25:20,019 --> 00:25:23,487 +the UI is changing, it's going to be changing this way point. + +476 +00:25:23,489 --> 00:25:26,524 +So, when it gets set, we're gonna have to update your, + +477 +00:25:26,526 --> 00:25:29,693 +our UI. So we'll call updateUI and make a method that does + +478 +00:25:29,695 --> 00:25:34,765 +that. Probably here when these well we'll talk about + +479 +00:25:34,767 --> 00:25:40,204 +that in a second, so let's get our private funk update ui. + +480 +00:25:40,640 --> 00:25:41,939 +So what do we do to update the ui? + +481 +00:25:41,941 --> 00:25:47,478 +I'm just gonna have the name, text fields, text equal + +482 +00:25:47,480 --> 00:25:52,116 +the waypoint to edit name. + +483 +00:25:52,818 --> 00:25:57,187 +And similarly the info text field Text equals + +484 +00:25:57,189 --> 00:26:02,226 +the Way PointTo Edit info. Okay. So + +485 +00:26:02,228 --> 00:26:05,996 +that's updating that. Probably also we should View Did Load. + +486 +00:26:05,998 --> 00:26:12,403 +And View Did Load will also update our UI. + +487 +00:26:12,405 --> 00:26:14,805 +That way when we're sequeway to it or + +488 +00:26:14,807 --> 00:26:18,442 +something if we set this before our outlets are set, + +489 +00:26:18,444 --> 00:26:23,714 +later on or. Now this is great for transferring information + +490 +00:26:23,716 --> 00:26:26,183 +from the waypoint to our text fields. + +491 +00:26:26,185 --> 00:26:28,986 +What about the other way? We edit in the text fields, + +492 +00:26:28,988 --> 00:26:31,956 +we have to edit our waypoint. So how are we going to that? + +493 +00:26:31,958 --> 00:26:33,591 +Well, there's actually a number of ways + +494 +00:26:33,593 --> 00:26:34,558 +to do that. I already showed you + +495 +00:26:34,560 --> 00:26:36,961 +in textfield how to do that with delegate messages. + +496 +00:26:36,963 --> 00:26:40,064 +I'm gonna show you how to do it now with radio stations. + +497 +00:26:40,066 --> 00:26:43,000 +Okay? Text fields actually broadcast on a radio station, + +498 +00:26:43,002 --> 00:26:46,236 +and one of the things they'll broadcast is my text changed. + +499 +00:26:46,238 --> 00:26:48,172 +So you can listen to that radio station, and + +500 +00:26:48,174 --> 00:26:51,108 +every time the text changes you can update whatever + +501 +00:26:51,110 --> 00:26:55,946 +thing you want to update. Now, before we do that, we + +502 +00:26:55,948 --> 00:26:58,616 +also need some things from the text fields delegate, however. + +503 +00:26:58,618 --> 00:27:01,218 +Like, I'd like to control the keyboard a little bit. + +504 +00:27:01,220 --> 00:27:03,954 +So, every time you press return in the keyboard, + +505 +00:27:03,956 --> 00:27:05,255 +I'd like to remove the keyboard, + +506 +00:27:05,257 --> 00:27:07,858 +just to clear it out of your way. So, how may I do that? + +507 +00:27:07,860 --> 00:27:13,831 +I'm gonna make sure that I am the main text fields delegate. + +508 +00:27:15,301 --> 00:27:15,933 +Okay so let's go ahead and + +509 +00:27:15,935 --> 00:27:19,903 +make sure we are a UI text field delegate. + +510 +00:27:20,673 --> 00:27:25,509 +Do the same thing with the info text field here. + +511 +00:27:25,511 --> 00:27:29,213 +All right, so now with the delegate. + +512 +00:27:29,215 --> 00:27:32,016 +What are we going to do here on that famous text + +513 +00:27:32,018 --> 00:27:35,586 +field should return target method right here. + +514 +00:27:35,588 --> 00:27:39,857 +I'm just gonna say text field, resign your first responder. + +515 +00:27:39,859 --> 00:27:43,360 +'Kay. And I'll return true, + +516 +00:27:43,362 --> 00:27:45,229 +'cause it can do whatever it wants there. + +517 +00:27:45,231 --> 00:27:47,064 +We don't have, you're not gonna have any action setups. + +518 +00:27:47,066 --> 00:27:49,433 +That's not gonna matter anyway. And, in fact, + +519 +00:27:49,435 --> 00:27:52,469 +another thing I'd like is when this NDC first appears, + +520 +00:27:52,471 --> 00:27:55,606 +I'd like to keyboard to appear. Okay I wanted it to + +521 +00:27:55,608 --> 00:27:58,842 +come up don't want to make the person touch in there. + +522 +00:27:58,844 --> 00:28:03,547 +So I'm gonna say let's do the name text field. Become + +523 +00:28:03,549 --> 00:28:07,851 +first response responder. Okay so that means when we reload, + +524 +00:28:07,853 --> 00:28:09,620 +we're gonna become the first responders. + +525 +00:28:09,622 --> 00:28:11,121 +Question. >> Sir, + +526 +00:28:11,123 --> 00:28:12,523 +did you say that the textfield should + +527 +00:28:12,525 --> 00:28:15,025 +return because this one said the textfieldShouldReturn? + +528 +00:28:15,027 --> 00:28:15,359 +>> Good catch, okay so + +529 +00:28:15,361 --> 00:28:17,161 +this is not supposed to be textfieldShouldClear, + +530 +00:28:17,163 --> 00:28:18,395 +this should be textfieldShouldReturn. + +531 +00:28:18,397 --> 00:28:23,100 +Okay, good catch, that's why you guys are here to catch + +532 +00:28:23,102 --> 00:28:27,671 +these mistakes. Yeah, so there we go, textfieldShouldReturn. + +533 +00:28:28,741 --> 00:28:31,809 +All right, so that's gonna manage our keyboard, but + +534 +00:28:31,811 --> 00:28:35,345 +now what about those radio stations? So let's go ahead, + +535 +00:28:35,347 --> 00:28:39,650 +and when, our view appears on screen, okay? + +536 +00:28:39,652 --> 00:28:40,184 +When we get viewDisappear, + +537 +00:28:40,186 --> 00:28:42,386 +we're gonna start listening to those radio stations. And + +538 +00:28:42,388 --> 00:28:45,856 +when we get viewWillDisappear, then we'll stop listening, all + +539 +00:28:45,858 --> 00:28:50,594 +right? So viewWillappear, or else you can do viewDidappear. + +540 +00:28:50,596 --> 00:29:00,704 +Super.viewDidAppear(animated). + +541 +00:29:00,706 --> 00:29:04,908 +All right. So we got viewDidAppear, + +542 +00:29:04,910 --> 00:29:09,279 +and so I am just going to say listenToTextFields Okay, + +543 +00:29:09,281 --> 00:29:17,321 +we'll make a little private func that does that. Okay, + +544 +00:29:17,323 --> 00:29:20,257 +so how we gonna listen to the text fields? Let's go ahead + +545 +00:29:20,259 --> 00:29:24,361 +and get ourselves the center, okay, the NSNotification, + +546 +00:29:24,363 --> 00:29:29,633 +NotificationCenter.defaultCen- ter. And + +547 +00:29:29,635 --> 00:29:31,802 +let's get the q that we want, we're going to do all of this + +548 +00:29:31,804 --> 00:29:36,774 +on the main Q. So ns operation q dot main q. All right now + +549 +00:29:36,776 --> 00:29:39,810 +that we have those two things, two little variables here, + +550 +00:29:39,812 --> 00:29:43,046 +I'm going to ask the center to listen to this radio station. + +551 +00:29:43,048 --> 00:29:47,584 +So I'm going to add observer for name. Return here, so + +552 +00:29:47,586 --> 00:29:50,854 +you can see this again, this is what we did last time. + +553 +00:29:50,856 --> 00:29:54,758 +All right, what's the name of the radio station? + +554 +00:29:54,760 --> 00:29:59,797 +It's UITextFieldTextDidChange, you can see it's got a couple + +555 +00:29:59,799 --> 00:30:03,367 +of other radio stations there too for begin end editing, but + +556 +00:30:03,369 --> 00:30:05,969 +I'm gonna get the one where every time the text change. + +557 +00:30:05,971 --> 00:30:08,338 +Every single character It's going to update. + +558 +00:30:08,340 --> 00:30:12,276 +The object here okay this one I'm gonna be listening to + +559 +00:30:12,278 --> 00:30:13,911 +the Name text field. Okay, and + +560 +00:30:13,913 --> 00:30:18,882 +we'll do it on the main queue. And here's the block. + +561 +00:30:18,884 --> 00:30:23,387 +So what's our block going to do here? We actually don't + +562 +00:30:23,389 --> 00:30:25,322 +even need to look at the notification, because we know + +563 +00:30:25,324 --> 00:30:28,325 +this is the Name text field right here this change. So + +564 +00:30:28,327 --> 00:30:32,563 +I'm just gonna say here, if I can let waypoint equal our + +565 +00:30:32,565 --> 00:30:36,667 +waypointToEdit, so if our waypointToEdit is not nil, + +566 +00:30:36,669 --> 00:30:38,101 +basically, then let's go ahead and + +567 +00:30:38,103 --> 00:30:43,874 +have the waypoint's name equal the nameTextFields.text, + +568 +00:30:43,876 --> 00:30:48,412 +all right? So every time this nameTextField changes, + +569 +00:30:48,414 --> 00:30:52,282 +we're going to update, our name. Okay. And + +570 +00:30:52,284 --> 00:30:56,320 +this needs to be self, because we're inside of closure here. + +571 +00:30:56,322 --> 00:31:00,424 +Okay, we'll do the exact same thing for the info text field. + +572 +00:31:00,426 --> 00:31:03,961 +One thing we could have done by the way, is have the object + +573 +00:31:03,963 --> 00:31:07,464 +we're listening to be nil and get all UI text and + +574 +00:31:07,466 --> 00:31:10,167 +then look at the text field that is sending it to us and + +575 +00:31:10,169 --> 00:31:13,170 +find out which one it is. But, what if we had other text + +576 +00:31:13,172 --> 00:31:15,505 +fields, other places in our UI that were listening, and + +577 +00:31:15,507 --> 00:31:18,075 +maybe they weren't good and that they kept listening even + +578 +00:31:18,077 --> 00:31:21,645 +when they were off screen, and all that getting all these. + +579 +00:31:21,647 --> 00:31:24,381 +This is a little bit more code in terms of alliance + +580 +00:31:24,383 --> 00:31:26,750 +right here, but it makes these closers really, + +581 +00:31:26,752 --> 00:31:30,320 +really, really simple. Okay? So, this is gonna be + +582 +00:31:30,322 --> 00:31:35,292 +the inform text field, update, now in viewDidAppear here, + +583 +00:31:35,294 --> 00:31:41,164 +we're listing the textfields, in viewWillDisappear, + +584 +00:31:43,302 --> 00:31:47,204 +We need to stop listening to these, okay so how do we do + +585 +00:31:47,206 --> 00:31:50,874 +that, okay we just ask the notification center. + +586 +00:31:50,876 --> 00:31:55,412 +DefaultCenter() to remove the Observer, + +587 +00:31:55,414 --> 00:31:58,615 +okay, that is this guy right here. + +588 +00:31:58,617 --> 00:32:01,551 +And same thing, we'll have to do another one for this. + +589 +00:32:01,553 --> 00:32:04,821 +So this is where we have to use the return value of this + +590 +00:32:04,823 --> 00:32:07,891 +addObserverForName. It actually returns something. + +591 +00:32:07,893 --> 00:32:09,793 +We'll call this one ntfObserver. + +592 +00:32:09,795 --> 00:32:12,829 +And this is just basically a cookie that represents + +593 +00:32:12,831 --> 00:32:14,298 +this radio station going here. So + +594 +00:32:14,300 --> 00:32:18,201 +we'll need a couple of private vars here. ntfObserver. + +595 +00:32:18,203 --> 00:32:21,505 +These things are of type NSObjectProtocol. Which + +596 +00:32:21,507 --> 00:32:25,008 +basically just means they're Objective-C compatible things, + +597 +00:32:25,010 --> 00:32:28,779 +they're part, they're visible to the Objective-C runtime. + +598 +00:32:28,781 --> 00:32:33,317 +Okay, and so we'll have info text field observer also. + +599 +00:32:35,955 --> 00:32:38,922 +Okay, so we'll let the ntfObserver equal that, + +600 +00:32:38,924 --> 00:32:41,892 +we'll have the itfObserver equal this. Okay, now + +601 +00:32:41,894 --> 00:32:45,495 +that we have these cookies, we, we wanna remove them here, + +602 +00:32:45,497 --> 00:32:48,098 +okay? We can just put them in here. But we wanna make sure + +603 +00:32:48,100 --> 00:32:51,034 +they're not nil, so I'm gonna say if I can let observer + +604 +00:32:51,036 --> 00:32:58,442 +equal the ntfObserver, then I will remove that observer. + +605 +00:32:58,811 --> 00:33:04,781 +And same thing down here. If I can let observer + +606 +00:33:04,783 --> 00:33:08,919 +equal to itfObserver, + +607 +00:33:08,921 --> 00:33:12,990 +then I will move that. Probably + +608 +00:33:12,992 --> 00:33:14,725 +could have made a nice little function that did this, so + +609 +00:33:14,727 --> 00:33:19,096 +that I don't have this kind of same repeated code style here. + +610 +00:33:19,098 --> 00:33:21,898 +Also, actually probably want to put these in another + +611 +00:33:21,900 --> 00:33:25,936 +private func. Maybe call it private func + +612 +00:33:25,938 --> 00:33:31,008 +stopListeningToTextFields. Put that in there, and + +613 +00:33:31,010 --> 00:33:37,047 +we'll call that from here. Okay? Arrange this + +614 +00:33:37,049 --> 00:33:41,685 +a little bit better. Put this down here. Okay, so basically, + +615 +00:33:41,687 --> 00:33:44,021 +listening and stop listening. So everyone understand that? + +616 +00:33:44,023 --> 00:33:46,323 +See how we're using radio stations to find out what's + +617 +00:33:46,325 --> 00:33:46,990 +happening in the text fields? + +618 +00:33:46,992 --> 00:33:50,627 +So it's kind of a, a fun way to do that. All right, + +619 +00:33:50,629 --> 00:33:54,331 +so the last thing we need to do here is our prepare for + +620 +00:33:54,333 --> 00:33:57,901 +segue, right? Over here, we, when we do this other segue, + +621 +00:33:57,903 --> 00:34:02,472 +this segue, this modal segue, we need to prepare for it. So + +622 +00:34:02,474 --> 00:34:09,713 +let's do that. Say else if segue.identifier == + +623 +00:34:09,715 --> 00:34:15,919 +EditUserWaypoint. Okay, that's the name of that, identifier. + +624 +00:34:15,921 --> 00:34:19,056 +Then in here we just wanna get that editable waypoint. + +625 +00:34:19,058 --> 00:34:20,057 +So I'm gonna see if I can + +626 +00:34:20,059 --> 00:34:22,592 +let the editableWaypoint equal the waypoint as + +627 +00:34:22,594 --> 00:34:26,063 +an EditableWaypoint, so make sure it's editable. It always + +628 +00:34:26,065 --> 00:34:29,866 +should be or we wouldn't be here. Let's put a comma here. + +629 +00:34:29,868 --> 00:34:33,336 +Then we can let our editable Waypoint view controller + +630 +00:34:33,338 --> 00:34:38,675 +equal the destination as EditWaypointViewController. + +631 +00:34:38,677 --> 00:34:43,447 +Okay, then we just set the EWVC's waypointToEdit, which + +632 +00:34:43,449 --> 00:34:50,420 +is its public model there, to the editableWaypoint, okay? + +633 +00:34:50,422 --> 00:34:52,022 +Now let's go back to our storyboard here and + +634 +00:34:52,024 --> 00:34:54,658 +take a look at how we're going to create the segue + +635 +00:34:54,660 --> 00:34:56,493 +right here. Because right now, there's no segue, + +636 +00:34:56,495 --> 00:35:00,997 +this thing is free as a bird out here flying around, okay? + +637 +00:35:00,999 --> 00:35:04,201 +So we want to edit it, so we're gonna do the same thing + +638 +00:35:04,203 --> 00:35:07,304 +we did here when we created this one, which is, + +639 +00:35:07,306 --> 00:35:11,875 +to drag from the, view controller, oops, + +640 +00:35:11,877 --> 00:35:15,479 +not that one, from this view controller right here. + +641 +00:35:15,481 --> 00:35:20,717 +We're gonna drag from this guy up to our new MVC. + +642 +00:35:20,719 --> 00:35:23,620 +So let's do that. Ctrl+drag up here. Now, this time though, + +643 +00:35:23,622 --> 00:35:26,890 +we're gonna do something new. This one's gonna be presented + +644 +00:35:26,892 --> 00:35:28,859 +modally. So instead of saying show and + +645 +00:35:28,861 --> 00:35:31,261 +having it appear inside this navigation controller, + +646 +00:35:31,263 --> 00:35:33,463 +we're gonna do present modally and it's gonna take over + +647 +00:35:33,465 --> 00:35:35,932 +the whole screen while we're editing the waypoint. + +648 +00:35:35,934 --> 00:35:38,135 +So we do present modally. Now let's go ahead and + +649 +00:35:38,137 --> 00:35:40,737 +take a look at this, sorry, let's make this a little + +650 +00:35:40,739 --> 00:35:45,442 +easier to see here. Okay. Let's go ahead and take a look + +651 +00:35:45,444 --> 00:35:48,645 +at this segue that was just created in the inspector. + +652 +00:35:48,647 --> 00:35:52,282 +Okay, so you obviously will need an identifier. + +653 +00:35:52,284 --> 00:35:55,919 +I think I called this one Edit Waypoint. + +654 +00:35:55,921 --> 00:35:59,523 +I hope that's what I called it. Let's go take a quick + +655 +00:35:59,525 --> 00:36:02,292 +look, make sure we get it right in our constants. Yes, + +656 +00:36:02,294 --> 00:36:05,962 +Edit Waypoint. That's what we called this segue right there. + +657 +00:36:06,732 --> 00:36:09,599 +And you can see it's got Present Modally here, + +658 +00:36:09,601 --> 00:36:13,570 +okay? And we'll take a look at these presentation styles down + +659 +00:36:13,572 --> 00:36:17,207 +here a little bit later. Okay? But for right now, + +660 +00:36:17,209 --> 00:36:19,209 +we just wanna present modally. So let's go ahead and + +661 +00:36:19,211 --> 00:36:26,082 +see what this does. All right, so + +662 +00:36:26,084 --> 00:36:29,052 +here we go, we're gonna drop an editable waypoint, okay? + +663 +00:36:29,054 --> 00:36:33,089 +It says Dropped, we can pick it up and move it, okay, + +664 +00:36:33,091 --> 00:36:35,892 +to anywhere we want, like to that airport again. And + +665 +00:36:35,894 --> 00:36:38,328 +hopefully, we press this i, we're gonna get this + +666 +00:36:38,330 --> 00:36:42,032 +modal segue to this new MVC. So hit the i, there we go, + +667 +00:36:42,034 --> 00:36:44,100 +modal segue. Now, we've got some problems here. + +668 +00:36:44,102 --> 00:36:46,736 +Looks like we've got a little problem with our + +669 +00:36:46,738 --> 00:36:49,973 +auto layout there. We'll have to take a look at that. And + +670 +00:36:49,975 --> 00:36:54,511 +in fact, we've gotta fix that, or we're not gonna be able to, + +671 +00:36:54,513 --> 00:36:57,714 +to edit this. So let's go back to our storyboard here and + +672 +00:36:57,716 --> 00:36:58,715 +take a look at what the problem, + +673 +00:36:58,717 --> 00:37:01,184 +probably was that thing where I said same width. + +674 +00:37:01,186 --> 00:37:04,821 +Somebody has the same width who shouldn't, I believe. + +675 +00:37:04,823 --> 00:37:06,823 +Maybe one of these stack views. + +676 +00:37:06,825 --> 00:37:09,559 +Let's take a look at this guy. So I'm just gonna, + +677 +00:37:09,561 --> 00:37:12,362 +when you get a problem with your auto layout, + +678 +00:37:12,364 --> 00:37:16,132 +it's kind of a good idea to make a little tour through + +679 +00:37:16,134 --> 00:37:16,733 +your various things. + +680 +00:37:16,735 --> 00:37:19,769 +You can even see, I've got red here, conflicting constraints, + +681 +00:37:19,771 --> 00:37:22,405 +so we know there's problems. And sure enough, look at this. + +682 +00:37:22,407 --> 00:37:26,109 +When I said, tried to make the description equal to the name, + +683 +00:37:26,111 --> 00:37:28,612 +I made this whole stack view equal to the name. + +684 +00:37:28,614 --> 00:37:31,615 +You see that? Equal width to name, this whole stack view, + +685 +00:37:31,617 --> 00:37:35,185 +so that's not good. So I don't want this, so I'm just gonna + +686 +00:37:35,187 --> 00:37:38,288 +delete that constraint. And now this has probably fixed + +687 +00:37:38,290 --> 00:37:40,357 +the problem, because you see I have no more warning + +688 +00:37:40,359 --> 00:37:44,227 +of conflicting constraints. Okay? So let's go try again, + +689 +00:37:44,229 --> 00:37:50,800 +see if that makes our UI look a little better. All right. + +690 +00:37:50,802 --> 00:37:56,172 +We'll drop here. Edit. That looks a lot better. + +691 +00:37:56,174 --> 00:37:59,743 +Okay. And you can see that it passed from the prepare for + +692 +00:37:59,745 --> 00:38:02,279 +segue, it passed our existing name and info, + +693 +00:38:02,281 --> 00:38:04,981 +which is just dropped with no info, into here. And + +694 +00:38:04,983 --> 00:38:07,784 +it also put the keyboard up, was nice. And if I get rid of, + +695 +00:38:07,786 --> 00:38:10,020 +hit return, it makes the keyboard go away. And + +696 +00:38:10,022 --> 00:38:13,290 +if I make one of these first responder, it comes back. + +697 +00:38:13,292 --> 00:38:14,891 +All right. And I can edit this. + +698 +00:38:14,893 --> 00:38:21,231 +Let's say, I'll say, I love it when people, do something, + +699 +00:38:21,233 --> 00:38:27,437 +okay. And how about, the fact is your name. + +700 +00:38:27,439 --> 00:38:31,408 +Okay, so here's our basically name of our waypoint and + +701 +00:38:31,410 --> 00:38:34,678 +the description. And so, uh-oh, how do we get out of + +702 +00:38:34,680 --> 00:38:38,615 +here? It's like, we can't get out. So this is a problem I + +703 +00:38:38,617 --> 00:38:41,818 +was telling you about. Modal, you have to provide a way for + +704 +00:38:41,820 --> 00:38:44,621 +your user to escape once they've edited whatever they + +705 +00:38:44,623 --> 00:38:47,757 +want to edit. Okay? So how are we gonna do that? Let's go + +706 +00:38:47,759 --> 00:38:49,993 +back to our storyboard. The simple way to do it + +707 +00:38:49,995 --> 00:38:53,029 +is to put this inside a navigation controller and + +708 +00:38:53,031 --> 00:38:57,000 +put a done button up there like we saw in the slides. + +709 +00:38:57,002 --> 00:38:58,201 +So let's do that. Let's go here, + +710 +00:38:58,203 --> 00:39:00,270 +Edit > Embed In > Navigation Controller, + +711 +00:39:00,272 --> 00:39:03,440 +it puts it in a navigation controller right here. And + +712 +00:39:03,442 --> 00:39:04,741 +we're just gonna put a Done button right there. + +713 +00:39:04,743 --> 00:39:09,145 +So let's go down here. We'll search for bar button item. + +714 +00:39:09,147 --> 00:39:11,815 +Here it is, a Bar Button Item. We'll put it right up here. + +715 +00:39:11,817 --> 00:39:15,919 +I think there's even a standard system one for that, + +716 +00:39:15,921 --> 00:39:20,824 +maybe. Yeah, there's a Done button right there, okay, for + +717 +00:39:20,826 --> 00:39:21,124 +clicking Done. + +718 +00:39:21,126 --> 00:39:24,594 +And then we'll just make this done button call a method + +719 +00:39:24,596 --> 00:39:26,229 +in this view controller, by the way, so + +720 +00:39:26,231 --> 00:39:29,165 +you can see our stack view frames are a little off now. + +721 +00:39:29,167 --> 00:39:32,235 +We can fix that clicking on here and + +722 +00:39:32,237 --> 00:39:35,372 +doing a update frames, moves that down. But + +723 +00:39:35,374 --> 00:39:38,875 +let's make this so that it sends a message to ourselves, + +724 +00:39:38,877 --> 00:39:41,578 +and then we'll dismiss ourselves. Okay, so + +725 +00:39:41,580 --> 00:39:46,149 +let's do that. We get here, we'll put this. + +726 +00:39:46,151 --> 00:39:48,585 +Let's make it a little more space for you there. Okay, + +727 +00:39:48,587 --> 00:39:52,856 +we'll put that dismiss, how about, I don't know, + +728 +00:39:52,858 --> 00:39:56,259 +right up after our view controller lifecycle here. + +729 +00:39:56,261 --> 00:39:59,062 +Okay? So I'm just gonna Ctrl+drag right in here. This + +730 +00:39:59,064 --> 00:40:02,932 +is gonna be an action. This is my done action, I'll call it. + +731 +00:40:02,934 --> 00:40:07,137 +Okay, BarButtonitem is gonna be the argument. Here it is. + +732 +00:40:07,139 --> 00:40:08,972 +Now remember, again, + +733 +00:40:08,974 --> 00:40:13,943 +let's go twofold width here. Remember, here, + +734 +00:40:13,945 --> 00:40:18,214 +we don't want to say just dismissViewControllerAnimated. + +735 +00:40:18,216 --> 00:40:23,353 +We want to get our presentingViewController. + +736 +00:40:23,355 --> 00:40:28,091 +That's the view controller that presented us and + +737 +00:40:28,093 --> 00:40:32,195 +ask it to dismiss us, okay. And we don't care when that + +738 +00:40:32,197 --> 00:40:34,864 +happens. Okay, so don't forget that. + +739 +00:40:34,866 --> 00:40:38,301 +I'm kind of putting this self here just to let you know I'm + +740 +00:40:38,303 --> 00:40:41,805 +talking about my self's presentingViewController but + +741 +00:40:41,807 --> 00:40:43,773 +you don't need self there obviously, + +742 +00:40:43,775 --> 00:40:46,810 +okay? Understand that? All right, so let's see that. + +743 +00:40:46,812 --> 00:40:54,150 +See how that makes this work. All right, + +744 +00:40:54,152 --> 00:40:58,922 +so we'll drop this. Go here, we'll edit it. Comes up, + +745 +00:40:58,924 --> 00:41:00,623 +we've got our Navigation Controller, it's there. + +746 +00:41:00,625 --> 00:41:03,460 +We probably should have put a title called edit waypoint or + +747 +00:41:03,462 --> 00:41:06,696 +something like that. So let's go ahead and edit this again. + +748 +00:41:06,698 --> 00:41:12,235 +So let's say the best thing. Okay, that's what our name is. + +749 +00:41:12,237 --> 00:41:17,740 +And the description is, the only way. All right, so we got + +750 +00:41:17,742 --> 00:41:21,177 +the best thing and the only way there. And we hit Done. + +751 +00:41:21,179 --> 00:41:25,048 +And it still says, Dropped, okay? Now why is that? + +752 +00:41:25,050 --> 00:41:27,851 +Well, that's because that callout was put up, and + +753 +00:41:27,853 --> 00:41:30,954 +when it's put up, it's loaded up with the waypoint's + +754 +00:41:30,956 --> 00:41:34,090 +information. And it stays that way all the time, + +755 +00:41:34,092 --> 00:41:37,894 +okay? The only time it changes is if it goes away and + +756 +00:41:37,896 --> 00:41:42,232 +comes back. When it comes back, it came back, okay? + +757 +00:41:42,234 --> 00:41:45,201 +Now we got a bug somewhere in our code cuz it should have + +758 +00:41:45,203 --> 00:41:49,706 +our subtitle there. But that was really annoying for + +759 +00:41:49,708 --> 00:41:51,474 +our user that they went and edited this and + +760 +00:41:51,476 --> 00:41:54,244 +when they came back it still said Dropped, okay. + +761 +00:41:54,246 --> 00:41:56,479 +So let's fix the bug so that this the only way, + +762 +00:41:56,481 --> 00:42:01,684 +which I think was the info was yeah, so here we go. + +763 +00:42:01,686 --> 00:42:05,755 +This should be info = the infoTextField, + +764 +00:42:05,757 --> 00:42:10,360 +okay? So how are we gonna fix that? Well, one thing about it + +765 +00:42:10,362 --> 00:42:16,165 +right off the bat is that when we click on this little i, + +766 +00:42:16,167 --> 00:42:19,402 +I'm gonna take this callout off the screen. Because I know + +767 +00:42:19,404 --> 00:42:22,572 +it's pretty much invalid right away because if I go over here + +768 +00:42:22,574 --> 00:42:23,673 +and change this to anything else, + +769 +00:42:23,675 --> 00:42:26,576 +that thing is no good anymore. So let's do that as step one. + +770 +00:42:26,578 --> 00:42:29,646 +Let's just take that callout away when we do this + +771 +00:42:29,648 --> 00:42:31,948 +performForSeg, performSegue. So + +772 +00:42:31,950 --> 00:42:33,516 +let's find where we do that performSegue, + +773 +00:42:33,518 --> 00:42:38,588 +it's in this funny little calloutAccessoryTapped, right? + +774 +00:42:38,590 --> 00:42:40,089 +Here's where we perform that segue. + +775 +00:42:40,091 --> 00:42:41,558 +And when we perform that segue, + +776 +00:42:41,560 --> 00:42:45,128 +we're going to remove that callout when we do that. And + +777 +00:42:45,130 --> 00:42:50,099 +so, we do that by saying mapView.deselectAnnotation + +778 +00:42:50,101 --> 00:42:52,735 +because the reason that callout is up is because this + +779 +00:42:52,737 --> 00:42:55,805 +annotation is selected. So, if we deselect this annotation, + +780 +00:42:55,807 --> 00:42:59,042 +it will remove that callout. And what do we wanna do? + +781 +00:42:59,044 --> 00:43:02,078 +We wanna remove the annotation in the view that our + +782 +00:43:02,080 --> 00:43:05,348 +callout is currently accessory control tapping. + +783 +00:43:05,350 --> 00:43:07,550 +And sure, we'll, we'll animate it, although it probably + +784 +00:43:07,552 --> 00:43:09,752 +doesn't matter that it's animated because we're gonna + +785 +00:43:09,754 --> 00:43:10,853 +put a modal thing right on top of it. But + +786 +00:43:10,855 --> 00:43:13,756 +maybe it'll be fading out as that's sliding in, that might + +787 +00:43:13,758 --> 00:43:18,428 +be kinda nice. Okay, so let's see if that fixes our problem. + +788 +00:43:22,233 --> 00:43:25,068 +All right, here we go. Put this on the airport here. + +789 +00:43:25,070 --> 00:43:27,704 +We'll click there, there's Dropped. We click. + +790 +00:43:27,706 --> 00:43:31,341 +Okay, we go to Dropped. And we'll put something in here. + +791 +00:43:31,343 --> 00:43:36,412 +Say I'm so excited, that's good. + +792 +00:43:36,414 --> 00:43:40,083 +Description, the fact is. Okay, and + +793 +00:43:40,085 --> 00:43:44,253 +we'll hit Done and hopefully, it's not showing it. + +794 +00:43:44,255 --> 00:43:45,855 +So at least it's not saying dropped, so + +795 +00:43:45,857 --> 00:43:49,192 +that's the improvement, right? But if we click on it, it's + +796 +00:43:49,194 --> 00:43:52,829 +showing it. So really what we'd like is when we come back + +797 +00:43:52,831 --> 00:43:55,732 +from that modal segue, we'd like it to put this thing back + +798 +00:43:55,734 --> 00:43:58,968 +up with the new information. Okay, so how are we gonna do + +799 +00:43:58,970 --> 00:44:02,839 +that, cuz we don't know when that modal thing goes away, + +800 +00:44:02,841 --> 00:44:05,708 +okay. It's just getting dismissed, right? So this is + +801 +00:44:05,710 --> 00:44:09,679 +a good opportunity to show you unwind. Okay, so we're gonna, + +802 +00:44:09,681 --> 00:44:12,915 +instead of hitting Done and having it dismiss ourselves, + +803 +00:44:12,917 --> 00:44:14,917 +we're going to do an unwind segue back to + +804 +00:44:14,919 --> 00:44:17,387 +our GPXController. And when it gets that message, + +805 +00:44:17,389 --> 00:44:20,657 +that special message, it'll know I'm gonna put this thing + +806 +00:44:20,659 --> 00:44:23,826 +back up, okay. So let's do that, so how do we do that? + +807 +00:44:23,828 --> 00:44:27,330 +We know that when we unwind, we always wanna create one of + +808 +00:44:27,332 --> 00:44:31,401 +this special methods, okay? And those special methods, + +809 +00:44:31,403 --> 00:44:34,904 +first of all, they're always IBActions, okay? + +810 +00:44:34,906 --> 00:44:38,141 +They can have any name that we want, so we'll call ours + +811 +00:44:38,143 --> 00:44:42,045 +updatedUserWaypoint because that's what happened, okay? + +812 +00:44:42,047 --> 00:44:44,414 +When the unwind happens, the user update waypoint + +813 +00:44:44,416 --> 00:44:48,785 +got updated. And the other thing that's special about it, + +814 +00:44:48,787 --> 00:44:52,288 +the argument has to be a UIStoryboardSegue, okay? + +815 +00:44:52,290 --> 00:44:54,957 +So this is the special method and this is all we need to do + +816 +00:44:54,959 --> 00:44:57,794 +to create one of these special message, methods. + +817 +00:44:57,796 --> 00:44:59,829 +We'll call it a func. All right, and + +818 +00:44:59,831 --> 00:45:03,599 +so now anybody can unwind to this as long as there's + +819 +00:45:03,601 --> 00:45:06,669 +something we presented. Any MVC that we've presented or + +820 +00:45:06,671 --> 00:45:09,672 +that was presented by somebody we presented, + +821 +00:45:09,674 --> 00:45:12,408 +etc., can now unwind back to us here. + +822 +00:45:12,410 --> 00:45:14,644 +Now what are we gonna do when we unbind back to here? + +823 +00:45:14,646 --> 00:45:18,314 +Well, we're gonna reselect that annotation that we + +824 +00:45:18,316 --> 00:45:22,452 +deselected when we left. So let's do that. + +825 +00:45:22,454 --> 00:45:25,054 +I'll create a little function to do that called sec, + +826 +00:45:25,056 --> 00:45:31,094 +selectWaypoint. Okay, and selectWaypoint, we gotta get + +827 +00:45:31,096 --> 00:45:34,030 +the waypoint we selected, it's a little tricky, watch this. + +828 +00:45:34,032 --> 00:45:38,668 +I'm gonna get the segue's sourceViewController. That's + +829 +00:45:38,670 --> 00:45:41,237 +the view controller that is sending us this unwind. + +830 +00:45:41,239 --> 00:45:43,272 +So that's gonna be the modal segue, right? + +831 +00:45:43,274 --> 00:45:45,274 +That's the source of the unwind. So + +832 +00:45:45,276 --> 00:45:46,776 +we're gonna get that sourceViewController. + +833 +00:45:46,778 --> 00:45:49,479 +And actually we'll get its contentViewController, + +834 +00:45:49,481 --> 00:45:55,451 +okay? And it has to be an EditWaypointViewController. + +835 +00:45:55,453 --> 00:45:57,253 +And if we're able to find that, + +836 +00:45:57,255 --> 00:46:00,223 +then we'll just get its waypointToEdit. Okay, + +837 +00:46:00,225 --> 00:46:03,659 +that's obviously the waypoint that we want to select. + +838 +00:46:03,661 --> 00:46:07,463 +So we need to, this method selectWaypoint. Let's do that. + +839 +00:46:07,465 --> 00:46:12,502 +func selectWaypoint takes a waypoint + +840 +00:46:12,504 --> 00:46:17,240 +which is at GPX.Waypoint, point. We'll + +841 +00:46:17,242 --> 00:46:19,675 +even make it optional if you wanna pass it in there. And + +842 +00:46:19,677 --> 00:46:24,614 +we'll just say if the waypoint != nil then we are gonna go + +843 +00:46:24,616 --> 00:46:29,786 +to the mapView and tell it to select an annotation, which is + +844 +00:46:29,788 --> 00:46:34,991 +the waypoint. Okay, remember that all of our waypoints + +845 +00:46:34,993 --> 00:46:37,827 +are annotations, so we can directly ask the mapView. This + +846 +00:46:37,829 --> 00:46:40,797 +is what's really nice about having some data structure + +847 +00:46:40,799 --> 00:46:43,866 +that we already have in our app, like a GPX waypoint, + +848 +00:46:43,868 --> 00:46:45,735 +implement that MK annotation protocol. + +849 +00:46:45,737 --> 00:46:48,704 +Because we're not having to constantly create these other + +850 +00:46:48,706 --> 00:46:51,774 +little things that contain all the waypoint in you know, + +851 +00:46:51,776 --> 00:46:54,777 +the MK notation information, we just get it directly from + +852 +00:46:54,779 --> 00:46:57,346 +our waypoints. Okay, so this is gonna select it. + +853 +00:46:57,348 --> 00:47:01,017 +So now we have to unwind to this instead of doing Done. + +854 +00:47:01,019 --> 00:47:03,653 +So let's go back to our storyboard here. Okay, + +855 +00:47:03,655 --> 00:47:06,622 +we've got this Done. I'm gonna disconnect Done + +856 +00:47:06,624 --> 00:47:09,525 +from this done method, right. So I'm just going here and + +857 +00:47:09,527 --> 00:47:12,395 +disconnecting it. So now it's not gonna send Done. And + +858 +00:47:12,397 --> 00:47:16,065 +in fact, if we go back to our EditWaypointViewController, + +859 +00:47:16,067 --> 00:47:19,368 +we can just delete this done method entirely whenever it + +860 +00:47:19,370 --> 00:47:22,905 +is, oops, there it is. Okay, we're not even gonna use that + +861 +00:47:22,907 --> 00:47:25,808 +anymore. Instead of doing that, we are going to unwind. + +862 +00:47:25,810 --> 00:47:28,878 +So let's go back here and unwind. So, how do we unwind? + +863 +00:47:28,880 --> 00:47:33,583 +Everyone remember? Ctrl+drag to this Exit button. Okay, + +864 +00:47:33,585 --> 00:47:36,519 +this is how you unwind. This is saying I want this Done + +865 +00:47:36,521 --> 00:47:39,021 +button to unwind, okay? To exit this MVC and + +866 +00:47:39,023 --> 00:47:41,624 +go back to one of its presenters. And look, when we + +867 +00:47:41,626 --> 00:47:44,861 +click, look what we see in the list! updatedUserWaypoint. + +868 +00:47:44,863 --> 00:47:46,796 +That method we put there with the special + +869 +00:47:46,798 --> 00:47:49,065 +IBAction in this segue as an argument, + +870 +00:47:49,067 --> 00:47:51,601 +okay? And every method in every MVC we ever + +871 +00:47:51,603 --> 00:47:54,203 +would've put in our entire app that was like that would + +872 +00:47:54,205 --> 00:47:57,173 +appear here. Yeah, question. >> Does the unwind only work + +873 +00:47:57,175 --> 00:47:59,342 +in a Navigation Controller? >> So the question, + +874 +00:47:59,344 --> 00:48:01,844 +does unwind only work inside a Navigation Controller? + +875 +00:48:01,846 --> 00:48:03,379 +And the answer is no, it works anywhere. + +876 +00:48:03,381 --> 00:48:06,616 +So you could have just a non-navigation controller MBC + +877 +00:48:06,618 --> 00:48:09,719 +present another one modally which presents another one + +878 +00:48:09,721 --> 00:48:13,055 +modally, and then you unwind back to either of those two. + +879 +00:48:13,057 --> 00:48:15,358 +So it has nothing to do with navigation controller. + +880 +00:48:15,360 --> 00:48:17,860 +This is not pop you now back or anything. + +881 +00:48:17,862 --> 00:48:21,664 +This is really just take this MBCs off until you get back to + +882 +00:48:21,666 --> 00:48:24,166 +the guy who implements this method, okay? + +883 +00:48:24,168 --> 00:48:26,535 +Now it would work in a navigation controller as well. + +884 +00:48:26,537 --> 00:48:29,772 +It would pop back from that as well, but it works in any + +885 +00:48:29,774 --> 00:48:33,476 +any environment basically. All right so I'm gonna click that + +886 +00:48:33,478 --> 00:48:37,113 +and that's gonna make the done button unwind to that method. + +887 +00:48:37,115 --> 00:48:42,618 +Okay so that method is gonna get called. So let's ugh. We + +888 +00:48:42,620 --> 00:48:47,256 +looking at this method when it happens. Let's go over here. + +889 +00:48:51,529 --> 00:48:55,665 +All right so drop the pin right here gonna click. + +890 +00:48:55,667 --> 00:48:59,435 +It says dropped right here. We're gonna go edit it. + +891 +00:48:59,437 --> 00:49:03,339 +Change it to something here, + +892 +00:49:03,341 --> 00:49:08,511 +how about the fact that you have to, + +893 +00:49:08,513 --> 00:49:11,747 +and we'll call this I'm so + +894 +00:49:11,749 --> 00:49:15,785 +happy, okay? So we're gonna hit done here and hopefully, + +895 +00:49:15,787 --> 00:49:18,187 +we're gonna see that call out, show up, + +896 +00:49:18,189 --> 00:49:20,056 +without having to click on anything and, sure enough, + +897 +00:49:20,058 --> 00:49:24,226 +it does. Okay because it unwind back, called this code + +898 +00:49:24,228 --> 00:49:26,529 +right here which selected that annotation. + +899 +00:49:26,531 --> 00:49:31,667 +This is back in our TPX view controller here, see? Okay, + +900 +00:49:31,669 --> 00:49:34,036 +everybody got the unwind there? All right, + +901 +00:49:34,038 --> 00:49:37,974 +the next segue we're gonna look at is popovers. Okay, + +902 +00:49:37,976 --> 00:49:41,110 +let's take a look at our app on iPad. And + +903 +00:49:41,112 --> 00:49:44,280 +to do this I'm actually gonna do it on my device over here. + +904 +00:49:44,282 --> 00:49:49,819 +So let's go up here, this is device and run this. + +905 +00:49:54,559 --> 00:49:57,760 +We made this to a universal app so it should work fine + +906 +00:49:57,762 --> 00:50:01,097 +over here. Sure enough there it is, zooming in to where we + +907 +00:50:01,099 --> 00:50:05,167 +are, okay. Here's our stuff we can zoom in here and + +908 +00:50:05,169 --> 00:50:08,304 +we can click on these things just like we could before. And + +909 +00:50:08,306 --> 00:50:14,643 +we can segue to see this. Okay all that stuff is nice. + +910 +00:50:14,645 --> 00:50:18,314 +And we can also add new pins, so I'm just long pressing. + +911 +00:50:18,316 --> 00:50:21,684 +There's a pin. Okay, let's click there, okay dropped. + +912 +00:50:21,686 --> 00:50:27,390 +We're going to edit it. Whoa. Okay this is pretty ugly UI. + +913 +00:50:27,392 --> 00:50:29,325 +Okay do not do this in your final project. + +914 +00:50:29,327 --> 00:50:31,660 +I cannot tell you how many final projects + +915 +00:50:31,662 --> 00:50:35,031 +think I've made it work on the iPad with this kind of UI. + +916 +00:50:35,033 --> 00:50:37,099 +Okay, this kind of UI looks ridiculous. + +917 +00:50:37,101 --> 00:50:39,568 +You're never going to have the name and description be that + +918 +00:50:39,570 --> 00:50:43,506 +long, okay. So you don't want that. There are other ways of + +919 +00:50:43,508 --> 00:50:45,608 +presenting modal NBC's that look a lot + +920 +00:50:45,610 --> 00:50:49,345 +better on iPad. So let's go pick one of them, let's go + +921 +00:50:49,347 --> 00:50:53,482 +back to our storyboard here, oops. Let's go back to our + +922 +00:50:53,484 --> 00:50:57,553 +storyboard and we're just gonna change our segue here, + +923 +00:50:57,555 --> 00:51:00,890 +this is the modal segue okay. That puts this thing up, + +924 +00:51:00,892 --> 00:51:03,893 +okay we're gonna inspect it and I'm gonna try a different + +925 +00:51:03,895 --> 00:51:07,396 +presentation like for example form sheet. So form sheet is + +926 +00:51:07,398 --> 00:51:10,399 +much more appropriate for the iPad. So let's go ahead and + +927 +00:51:10,401 --> 00:51:12,935 +run this. See what form sheet looks like. The form sheet + +928 +00:51:12,937 --> 00:51:16,472 +modal presentation. It's just a different presentation than + +929 +00:51:16,474 --> 00:51:17,540 +take over the whole screen. + +930 +00:51:17,542 --> 00:51:18,574 +It still takes over the whole screen, + +931 +00:51:18,576 --> 00:51:21,877 +it just does it a little more space efficiently here. + +932 +00:51:21,879 --> 00:51:24,013 +All right, so I'm dropping a pin there and + +933 +00:51:24,015 --> 00:51:24,580 +we're gonna edit it. And + +934 +00:51:24,582 --> 00:51:28,617 +you can see this gives a much more sensible looking space. + +935 +00:51:28,619 --> 00:51:32,154 +Now the background here on the side, the grey on the side, + +936 +00:51:32,156 --> 00:51:34,423 +okay, is not active. I can't do anything with it so + +937 +00:51:34,425 --> 00:51:36,525 +it's still modal, it's still completely taking over, + +938 +00:51:36,527 --> 00:51:40,029 +it just presenting it a little nicer here. Okay, and I can + +939 +00:51:40,031 --> 00:51:44,767 +still do all the things that I would do here. Ya know, hello. + +940 +00:51:44,769 --> 00:51:49,271 +Okay so, that's nice but, really on the iPad, what would + +941 +00:51:49,273 --> 00:51:53,776 +be really cool is to do it in a little pop over right there. + +942 +00:51:53,778 --> 00:51:57,179 +Okay to have the name, and info just be in that small, + +943 +00:51:57,181 --> 00:52:00,249 +little pop over pointing right at that little pin, + +944 +00:52:00,251 --> 00:52:03,352 +that would be a much better UI. And so it's great because + +945 +00:52:03,354 --> 00:52:06,222 +we can learn how to do pop overs. So lets do that, how + +946 +00:52:06,224 --> 00:52:11,393 +are we gonna do popovers? So a, and when we have a popover + +947 +00:52:11,395 --> 00:52:14,630 +we're not gonna want this Navigation Controller in here, + +948 +00:52:14,632 --> 00:52:17,032 +okay? We'll zoom out so you can see it. + +949 +00:52:17,034 --> 00:52:20,069 +Okay if when we have a popover to do this we wanna get + +950 +00:52:20,071 --> 00:52:21,303 +rid of this Navigation Controller here. + +951 +00:52:21,305 --> 00:52:24,140 +So I'm gonna delete that. So we have this, okay? + +952 +00:52:24,142 --> 00:52:27,276 +Now, I'm just gonnato create a popover in the same way, + +953 +00:52:27,278 --> 00:52:28,677 +as we created all the other ones, okay? + +954 +00:52:28,679 --> 00:52:32,781 +Which is control drag from here up to here. But + +955 +00:52:32,783 --> 00:52:36,285 +this time, I'm gonna choose present as popover. Okay and + +956 +00:52:36,287 --> 00:52:40,422 +this creates this right here and you can see here's the pop + +957 +00:52:40,424 --> 00:52:43,659 +over segue. Now we of course need an identifier for it. + +958 +00:52:43,661 --> 00:52:45,728 +We're going to do the same identifier cause we're + +959 +00:52:45,730 --> 00:52:47,630 +going to have the same prepare segue as we have for + +960 +00:52:47,632 --> 00:52:52,168 +the mog modal one which was edit waypoint. All right. + +961 +00:52:52,170 --> 00:52:55,771 +Notice popover has some extra things down here. Okay, and + +962 +00:52:55,773 --> 00:52:58,741 +this mostly has to do with when I put this popover up, + +963 +00:52:58,743 --> 00:53:01,911 +okay, where do you want it to appear? And part of where + +964 +00:53:01,913 --> 00:53:04,380 +it wants to appear is where you are going to allow + +965 +00:53:04,382 --> 00:53:07,583 +the Popovers little arrow to point, point up, or left, or + +966 +00:53:07,585 --> 00:53:10,920 +down, or right that's gonna to kind of position it a little + +967 +00:53:10,922 --> 00:53:13,689 +bit. In our case we'll let it point any direction. + +968 +00:53:13,691 --> 00:53:17,526 +So, depending on whether your weight point is up in the left + +969 +00:53:17,528 --> 00:53:18,761 +corner, in the right corner, + +970 +00:53:18,763 --> 00:53:20,362 +we'll let the pop over be above it, below it, + +971 +00:53:20,364 --> 00:53:24,300 +whatever the system thinks is best. But the popover also + +972 +00:53:24,302 --> 00:53:26,936 +needs needs an anchor, which is when I come up I've gotta + +973 +00:53:26,938 --> 00:53:29,471 +point at something. And we're not bringing this up with + +974 +00:53:29,473 --> 00:53:32,308 +a bar button, or something we can point to. We're bringing + +975 +00:53:32,310 --> 00:53:35,311 +it up by clicking on this little annotation thing. So, + +976 +00:53:35,313 --> 00:53:39,748 +we really want the anchor to be those pins. Okay so + +977 +00:53:39,750 --> 00:53:42,218 +those pins are in the map view so + +978 +00:53:42,220 --> 00:53:45,754 +I'm going to have the anchor right here be the map view and + +979 +00:53:45,756 --> 00:53:48,591 +then in code I'm going to specify a rectangle in the map + +980 +00:53:48,593 --> 00:53:51,794 +view which contains that little annotation view. So + +981 +00:53:51,796 --> 00:53:55,731 +the way I make the map view be anchor is I Ctrl+Drag + +982 +00:53:55,733 --> 00:53:59,168 +over to this. Okay, from the little circle. Like that and + +983 +00:53:59,170 --> 00:54:01,070 +you can see it puts the map view in there. + +984 +00:54:01,072 --> 00:54:03,272 +So now it's saying okay, I understand that + +985 +00:54:03,274 --> 00:54:06,342 +I'm gonna point up pointing to somewhere in the map view. + +986 +00:54:06,344 --> 00:54:08,010 +In your code you better tell me where and + +987 +00:54:08,012 --> 00:54:11,480 +we're gonna tell you, tell it where, okay? + +988 +00:54:13,551 --> 00:54:16,785 +Okay, okay, all right. + +989 +00:54:16,787 --> 00:54:20,022 +So where are we gonna set that little rectangle, okay? + +990 +00:54:20,024 --> 00:54:23,659 +We're gonna set that in our prepareforsegue, for + +991 +00:54:23,661 --> 00:54:26,862 +this segue, that's where you set up all your popover stuff, + +992 +00:54:26,864 --> 00:54:28,831 +is in the prepareforsegue for that segue. + +993 +00:54:28,833 --> 00:54:32,635 +So here is that part of this prepareforsegue, + +994 +00:54:32,637 --> 00:54:35,871 +write the edit user waypoint, part of the prepareforsegue. + +995 +00:54:35,873 --> 00:54:39,241 +All we're gonna do here is get the popover presentation + +996 +00:54:39,243 --> 00:54:43,178 +controller. So if we can get that, we get it from the MBC + +997 +00:54:43,180 --> 00:54:47,983 +we're presenting. So in this case it's the EWVC, the edit + +998 +00:54:47,985 --> 00:54:50,719 +wavepoint view controller. We get it from that. + +999 +00:54:50,721 --> 00:54:51,720 +And we get it from this method, + +1000 +00:54:51,722 --> 00:54:55,257 +pop over presentation controller. Now if we're now + +1001 +00:54:55,259 --> 00:54:58,427 +popping over this would be null. This code won't execute, + +1002 +00:54:58,429 --> 00:55:01,230 +excellent, okay? But if we're doing a popover, then it will + +1003 +00:55:01,232 --> 00:55:04,800 +not be null. So in here we configure the popover + +1004 +00:55:04,802 --> 00:55:06,535 +presentation controller and you can go look at the doc, + +1005 +00:55:06,537 --> 00:55:10,506 +but one of the things you can do is the source rectangle + +1006 +00:55:10,508 --> 00:55:14,710 +that it's gonna point to in your anchor view, okay? And + +1007 +00:55:14,712 --> 00:55:16,278 +what is this gonna be? Well that's easy for + +1008 +00:55:16,280 --> 00:55:20,683 +us, that's just gonna be the annotation view's frame. Okay, + +1009 +00:55:20,685 --> 00:55:21,650 +the frame of the little pin, + +1010 +00:55:21,652 --> 00:55:26,355 +that's where we want the popover to point. Make sense? + +1011 +00:55:26,357 --> 00:55:29,091 +All right so, so, let's run this, see what it looks like. + +1012 +00:55:39,270 --> 00:55:43,939 +All right? So, we'll drop this here, click on it and + +1013 +00:55:43,941 --> 00:55:47,710 +whoa! Well, hm, okay we're makin progress but I + +1014 +00:55:47,712 --> 00:55:52,581 +don't think we're quite there. So what's wrong with this? + +1015 +00:55:52,583 --> 00:55:54,883 +Well, one thing is that thing is huge! + +1016 +00:55:54,885 --> 00:55:57,753 +Way bigger than it needs to be! Why is it so big? + +1017 +00:55:57,755 --> 00:56:00,456 +The answer is because no one told it what size it was + +1018 +00:56:00,458 --> 00:56:03,826 +supposed to be. Okay, and you remember from the slides, + +1019 +00:56:03,828 --> 00:56:05,594 +we do this in an object-oriented way. + +1020 +00:56:05,596 --> 00:56:09,164 +The system wants the MVC that's being put up to say, + +1021 +00:56:09,166 --> 00:56:13,669 +what size do you want to be? Now, what's really cool is, + +1022 +00:56:13,671 --> 00:56:18,207 +I'm gonna calculate that size using Auto Layout, okay? + +1023 +00:56:18,209 --> 00:56:21,110 +I'm basically gonna say, make yourself as small as you can + +1024 +00:56:21,112 --> 00:56:23,746 +and still obey the Auto Layout rules, okay? And you can do + +1025 +00:56:23,748 --> 00:56:26,482 +that with one line of code. So it's really cool. All right, + +1026 +00:56:26,484 --> 00:56:28,884 +so where am I gonna do that? So I'm gonna do that in my + +1027 +00:56:28,886 --> 00:56:30,185 +EditWaypointViewController. Okay, + +1028 +00:56:30,187 --> 00:56:32,955 +this is the view controller that's coming up there. So + +1029 +00:56:32,957 --> 00:56:33,655 +it's the one responsible for + +1030 +00:56:33,657 --> 00:56:37,159 +setting its preferred size. And I'm gonna do it in + +1031 +00:56:37,161 --> 00:56:42,231 +the view controller life cycle method viewWillLayoutSubviews. + +1032 +00:56:42,233 --> 00:56:45,334 +Okay, so, I know that in viewWillLayOutSubviews, + +1033 +00:56:45,336 --> 00:56:49,071 +my balance is gonna be set to whatever the latest thing is. + +1034 +00:56:49,073 --> 00:56:53,375 +So I know I'm gonna have some good, bounds situation. + +1035 +00:56:53,377 --> 00:56:55,677 +So I'm just gonna, in here, I'm gonna set my, + +1036 +00:56:55,679 --> 00:57:02,151 +preferred content size, that's the size that I prefer to be, + +1037 +00:57:02,153 --> 00:57:04,119 +to be the following thing, + +1038 +00:57:04,121 --> 00:57:09,825 +view dot, okay, and all views implement this cool method, + +1039 +00:57:09,827 --> 00:57:17,299 +systemLayoutSizeFittingSize, okay. + +1040 +00:57:17,301 --> 00:57:20,402 +So that's basically saying, use Auto Layout and + +1041 +00:57:20,404 --> 00:57:20,803 +tell me what size will + +1042 +00:57:20,805 --> 00:57:25,407 +fit in this size the best. And there's a really cool size, + +1043 +00:57:25,409 --> 00:57:29,845 +predefined size, called the UILayoutFittingSize. + +1044 +00:57:29,847 --> 00:57:33,282 +There's a ExpandedSize, which means, make me as big as you + +1045 +00:57:33,284 --> 00:57:36,852 +can and obey Auto Layout, and then there's CompressedSize, + +1046 +00:57:36,854 --> 00:57:40,389 +which is, make me as small as you can. Okay, so, I'm gonna + +1047 +00:57:40,391 --> 00:57:43,559 +go for CompressedSize, okay, and it's going to give me + +1048 +00:57:43,561 --> 00:57:46,962 +a size that fits as small as possible using Auto Layout. + +1049 +00:57:46,964 --> 00:57:48,931 +Okay, so this is a really cool little method, + +1050 +00:57:48,933 --> 00:57:52,534 +it's how you get Auto Layout to calculate a size for you. + +1051 +00:57:52,536 --> 00:57:55,637 +All right, so let's see, now that the size is right, + +1052 +00:57:55,639 --> 00:57:58,974 +let's go see if that's going to fix things. I don't think + +1053 +00:57:58,976 --> 00:58:02,544 +it's gonna be quite right, but it's gonna be close. + +1054 +00:58:07,485 --> 00:58:11,854 +All right, here we go, drop a pin. We're gonna click on it, + +1055 +00:58:11,856 --> 00:58:16,658 +oops, I clicked on the side of it. Okay, and edit it. Okay, + +1056 +00:58:16,660 --> 00:58:19,828 +now, this is really close. Okay, it's really nice. + +1057 +00:58:19,830 --> 00:58:22,364 +See how it's making it just the right size? + +1058 +00:58:22,366 --> 00:58:25,868 +The problem is, the text editing part is pretty small. + +1059 +00:58:25,870 --> 00:58:29,972 +Because look what it did, it sized it to the word Dropped. + +1060 +00:58:29,974 --> 00:58:33,175 +Okay, and why did it do that? Because in our Auto Layout, + +1061 +00:58:33,177 --> 00:58:36,111 +we didn't tell anything else about what size it should be. + +1062 +00:58:36,113 --> 00:58:37,346 +So it put the contents in there, and + +1063 +00:58:37,348 --> 00:58:39,882 +it made it as small as possible and fit the contents. + +1064 +00:58:39,884 --> 00:58:43,886 +So we actually wanna go back to our storyboard and put + +1065 +00:58:43,888 --> 00:58:47,289 +a minimum, reasonable minimum size for those text fields so + +1066 +00:58:47,291 --> 00:58:50,459 +that they will give the person room to type something in. + +1067 +00:58:50,461 --> 00:58:53,729 +Okay? The other thing is, the background is white. + +1068 +00:58:53,731 --> 00:58:56,698 +This may be hard for you to see on that screen. But if you + +1069 +00:58:56,700 --> 00:59:00,769 +look where the little arrow is pointing next to the word + +1070 +00:59:00,771 --> 00:59:04,540 +description there, that's actually semitransparent. + +1071 +00:59:04,542 --> 00:59:06,041 +And then also where the name and + +1072 +00:59:06,043 --> 00:59:09,077 +description is is a white box. Okay, so it's actually + +1073 +00:59:09,079 --> 00:59:12,781 +possible to have the whole thing be this semitransparent, + +1074 +00:59:12,783 --> 00:59:15,284 +so that we can kind of see that we're on top of a map. + +1075 +00:59:15,286 --> 00:59:19,221 +It won't feel so kind of obnoxious, this white box. And + +1076 +00:59:19,223 --> 00:59:21,657 +the way to do that is just to make this MVC have + +1077 +00:59:21,659 --> 00:59:25,894 +a background of clear. Okay, then it's just going to appear + +1078 +00:59:25,896 --> 00:59:28,730 +clear on top of the popover's background, + +1079 +00:59:28,732 --> 00:59:30,399 +which is semitransparent. + +1080 +00:59:30,401 --> 00:59:32,034 +Okay, so we're gonna fix both those things at once. + +1081 +00:59:32,036 --> 00:59:35,370 +So we're going back to our storyboard here. Okay, so + +1082 +00:59:35,372 --> 00:59:38,674 +we're gonna make it so that these text fields right here, + +1083 +00:59:38,676 --> 00:59:41,343 +okay, are a reasonable minimal, minimum size. + +1084 +00:59:41,345 --> 00:59:43,645 +So what would be a reasonable minimum size? + +1085 +00:59:43,647 --> 00:59:48,483 +Let's go here to our width here and height. And so + +1086 +00:59:48,485 --> 00:59:52,354 +we could say a width of maybe, I don't know, 250 points? + +1087 +00:59:52,356 --> 00:59:54,289 +This is something that you could play with in your UI. + +1088 +00:59:54,291 --> 00:59:57,025 +I really only need to set one of these, because these + +1089 +00:59:57,027 --> 00:59:59,194 +are already gonna be the same width. And so + +1090 +00:59:59,196 --> 01:00:02,130 +that's gonna force these to be the same width. But actually, + +1091 +01:00:02,132 --> 01:00:06,835 +I don't want it to be exactly 250. I want it to be at least + +1092 +01:00:06,837 --> 01:00:11,106 +250, okay. Because if the name is really long, and + +1093 +01:00:11,108 --> 01:00:14,176 +it'll fit without going off the edge of the screen, sure, + +1094 +01:00:14,178 --> 01:00:18,714 +you can do it. So I add the constraint here to be 250. + +1095 +01:00:18,716 --> 01:00:21,149 +And you can see that it makes it exactly 250, but + +1096 +01:00:21,151 --> 01:00:23,785 +I don't want that. So I'm gonna go over here to my + +1097 +01:00:23,787 --> 01:00:27,889 +dimensions inspector and look at this width 250. I'm gonna + +1098 +01:00:27,891 --> 01:00:32,427 +edit it and change it to greater than or equal to 250, + +1099 +01:00:32,429 --> 01:00:38,266 +okay? So understand that Auto Layout is pretty configurable. + +1100 +01:00:38,268 --> 01:00:40,836 +You don't have to make things always be exactly certain + +1101 +01:00:40,838 --> 01:00:47,109 +sizes, okay? So we'll go ahead and adjust our frames here. + +1102 +01:00:47,111 --> 01:00:52,147 +Okay, got that? Okay, now what about the clear? That's really + +1103 +01:00:52,149 --> 01:00:54,616 +simple. I'm just gonna click the background view here, + +1104 +01:00:54,618 --> 01:00:56,451 +and instead of having it be white, okay, + +1105 +01:00:56,453 --> 01:00:58,987 +this background view, I'm gonna have it be the default, + +1106 +01:00:58,989 --> 01:01:04,192 +which is clear. Okay? So let's run it again. + +1107 +01:01:13,671 --> 01:01:14,870 +Okay, yes, so that's working. + +1108 +01:01:14,872 --> 01:01:16,938 +All right, so let's drop a pin. Okay. + +1109 +01:01:16,940 --> 01:01:22,310 +We're gonna edit it, here we go. Boom. Perfect. Okay, + +1110 +01:01:22,312 --> 01:01:24,680 +give us a little extra space to work with. + +1111 +01:01:24,682 --> 01:01:25,614 +We can see, can you see that? + +1112 +01:01:25,616 --> 01:01:26,648 +Yeah, you can see it's kind of a little bit see through. + +1113 +01:01:26,650 --> 01:01:30,318 +You can see it's a little bit green behind that, looks a, + +1114 +01:01:30,320 --> 01:01:34,189 +a lot nicer. Okay so, excellent. + +1115 +01:01:34,191 --> 01:01:37,659 +Wow, popovers are great. I'm sure this didn't do any damage + +1116 +01:01:37,661 --> 01:01:40,896 +on the iPhone side. Let's go take a look, okay? + +1117 +01:01:40,898 --> 01:01:47,436 +iPhone. Sure the iPhone looks just great. + +1118 +01:01:50,307 --> 01:01:53,709 +All right, here it is. We'll drop a pin. + +1119 +01:01:53,711 --> 01:01:56,912 +All right, there it is, all right, here we go. Oops. + +1120 +01:01:56,914 --> 01:02:00,215 +Ugh. Okay, well, clearly we totally broke, and + +1121 +01:02:00,217 --> 01:02:03,118 +understandably, broke our iPhone side of this. + +1122 +01:02:03,120 --> 01:02:05,787 +So what's wrong here, what's going on? Well, first of all, + +1123 +01:02:05,789 --> 01:02:07,456 +we took it out of the navigation controller, so + +1124 +01:02:07,458 --> 01:02:09,925 +we lost our done button, okay? So we're done, okay? + +1125 +01:02:09,927 --> 01:02:13,261 +[LAUGH] Second one is, we made the background clear, so + +1126 +01:02:13,263 --> 01:02:17,065 +it's looking into the void. Because, we know that when + +1127 +01:02:17,067 --> 01:02:20,502 +it adapts, okay, first of all, why is it coming up this way? + +1128 +01:02:20,504 --> 01:02:23,338 +Well, the system knows this is horizontally compact, so + +1129 +01:02:23,340 --> 01:02:26,074 +it adapted from popover to full screen modal, okay. + +1130 +01:02:26,076 --> 01:02:30,245 +Full screen modal completely covers + +1131 +01:02:30,247 --> 01:02:32,514 +the thing underneath it, doesn't show anything, + +1132 +01:02:32,516 --> 01:02:34,616 +doesn't show through, it completely covers it. + +1133 +01:02:34,618 --> 01:02:38,420 +And it covers it with the void, the great void, okay. + +1134 +01:02:38,422 --> 01:02:41,656 +And since we're looking clear into the void, it's black, + +1135 +01:02:41,658 --> 01:02:44,126 +okay, the void happens to be black. All right, so that's + +1136 +01:02:44,128 --> 01:02:47,028 +why this looks so terrible. So what are we gonna do about + +1137 +01:02:47,030 --> 01:02:51,066 +this, okay? There's a number of things that we can do + +1138 +01:02:51,068 --> 01:02:55,704 +to make this a lot better. So, actually, before we do this, + +1139 +01:02:55,706 --> 01:02:58,907 +let's do one other quick thing. I wanna show you one + +1140 +01:02:58,909 --> 01:03:01,910 +other quick thing. Let's go back over to our, + +1141 +01:03:01,912 --> 01:03:07,215 +look at our iPad here, okay? We're back on the iPad there. + +1142 +01:03:07,217 --> 01:03:11,319 +Okay, so when I change this, let's say I change something + +1143 +01:03:11,321 --> 01:03:15,857 +here, like, you know, let's change it to, I'm not going, + +1144 +01:03:15,859 --> 01:03:19,194 +okay, I'm not going, and I hit return. And now, + +1145 +01:03:19,196 --> 01:03:22,397 +how do we dismiss a popover? We just hit somewhere else, + +1146 +01:03:22,399 --> 01:03:26,535 +right? So here we go, tap. Look at that. It didn't + +1147 +01:03:26,537 --> 01:03:29,838 +show it to us. Remember, when we had it on the iPhone, + +1148 +01:03:29,840 --> 01:03:33,008 +when I clicked Done, it showed it. Now it's not showing. + +1149 +01:03:33,010 --> 01:03:36,511 +Now, if I click on it, okay, it worked, that's great. But + +1150 +01:03:36,513 --> 01:03:39,815 +no, we want it to show just like it did on the iPhone. + +1151 +01:03:39,817 --> 01:03:44,085 +So how are we gonna fix that? That's pretty easy to fix. + +1152 +01:03:44,087 --> 01:03:47,455 +We're gonna use, over here in our GPX controller, + +1153 +01:03:47,457 --> 01:03:50,625 +this same popover presentation controller. + +1154 +01:03:50,627 --> 01:03:53,595 +We're going to implement one of its delegate methods. + +1155 +01:03:53,597 --> 01:03:55,931 +Okay, so we're going to set ourself as the delegate + +1156 +01:03:55,933 --> 01:03:58,767 +of this pop-over presentation controller, which means, + +1157 +01:03:58,769 --> 01:04:02,370 +of course, we have to go up here. And say that we + +1158 +01:04:02,372 --> 01:04:07,475 +are a UIPopoverPresentationControll- + +1159 +01:04:07,477 --> 01:04:11,880 +erDeligate, okay? And that, all right. So we're + +1160 +01:04:11,882 --> 01:04:14,216 +PopoverPresentationController- Deligate. Which + +1161 +01:04:14,218 --> 01:04:16,685 +PopoverPresentationController- Deligate method are we gonna + +1162 +01:04:16,687 --> 01:04:20,522 +implement here? We're gonna implement the one where we + +1163 +01:04:20,524 --> 01:04:26,595 +find out that it dismissed, dismiss pop over. + +1164 +01:04:26,597 --> 01:04:28,096 +Okay, so this message gets sent to + +1165 +01:04:28,098 --> 01:04:29,898 +the pop over presentation controller's delegate, + +1166 +01:04:29,900 --> 01:04:31,933 +when the pop over is dismissed. A perfect time for + +1167 +01:04:31,935 --> 01:04:35,370 +us to reselect that waypoint. Okay, we have that method + +1168 +01:04:35,372 --> 01:04:37,539 +still, stay select waypoint, so let's go ahead and + +1169 +01:04:37,541 --> 01:04:39,774 +do it. How do we get it this time? Well, we're going to + +1170 +01:04:39,776 --> 01:04:42,777 +get this from the pop over presentation controller. Okay? + +1171 +01:04:42,779 --> 01:04:46,648 +We're gonna get it's presented ViewController, okay? + +1172 +01:04:46,650 --> 01:04:48,917 +That's the controller its presenting which is our + +1173 +01:04:48,919 --> 01:04:52,220 +editable view, waypoint view controller. And it better be + +1174 +01:04:52,222 --> 01:04:56,291 +an EditWaypointViewController, okay? And if it is, + +1175 +01:04:56,293 --> 01:05:01,363 +then we can just get the waypoint to edit, okay? So + +1176 +01:05:01,365 --> 01:05:07,736 +now, we're on this. Okay. So we'll drop, + +1177 +01:05:07,871 --> 01:05:15,043 +click, go up here, change this to something, random words. + +1178 +01:05:15,879 --> 01:05:20,048 +The only thing is tip away, and we got it. Okay. + +1179 +01:05:20,050 --> 01:05:22,317 +So that's a great use of that little delegate. But + +1180 +01:05:22,319 --> 01:05:25,620 +there are even better uses of that little delegate. + +1181 +01:05:25,622 --> 01:05:28,256 +And a lot of them have to do with this adaptation + +1182 +01:05:28,258 --> 01:05:31,526 +behavior, okay? The way that the system is adopting to that + +1183 +01:05:31,528 --> 01:05:33,962 +horizontally compact environment and + +1184 +01:05:33,964 --> 01:05:38,199 +putting that thing up on our iPhone + +1185 +01:05:38,201 --> 01:05:42,037 +in this really obnoxious way. Okay so let's go and + +1186 +01:05:42,039 --> 01:05:45,707 +fix some of these things. One thing we could do to fix this + +1187 +01:05:45,709 --> 01:05:50,478 +is we could make it not adapt. Okay? We can make it just so + +1188 +01:05:50,480 --> 01:05:53,081 +that it uses popover on iPhone. It doesn't do this + +1189 +01:05:53,083 --> 01:05:55,850 +whole putting a modal one up instead. Okay so + +1190 +01:05:55,852 --> 01:05:59,321 +how would we do that? All right, that one we're gonna + +1191 +01:05:59,323 --> 01:06:01,790 +implement a different delegate method here. + +1192 +01:06:01,792 --> 01:06:06,461 +Popover delegate. This one is called the, + +1193 +01:06:06,463 --> 01:06:11,066 +note here, adaptivePresentationStyleforP- + +1194 +01:06:11,068 --> 01:06:15,870 +resentationController. Okay, this guy right here. Okay, + +1195 +01:06:15,872 --> 01:06:19,040 +adapt to presentation style for presentation controller, + +1196 +01:06:19,042 --> 01:06:20,208 +actually we want a different one, + +1197 +01:06:20,210 --> 01:06:23,645 +we want the one that gives us the trade collection. + +1198 +01:06:24,781 --> 01:06:29,951 +AdaptivePresentationStyle, it's this one. Okay? + +1199 +01:06:29,953 --> 01:06:32,954 +So this one is basically asking us, let me make it so + +1200 +01:06:32,956 --> 01:06:36,324 +you can see it a little better here. Okay? + +1201 +01:06:36,326 --> 01:06:39,494 +It has two arguments here and it returns + +1202 +01:06:39,496 --> 01:06:42,230 +a ModalPresentationStyle. So this is saying, for + +1203 +01:06:42,232 --> 01:06:45,533 +a given trait collection like horizontally compact or + +1204 +01:06:45,535 --> 01:06:49,404 +whatever how do you want to present this + +1205 +01:06:49,406 --> 01:06:52,607 +thing in when you're adapting. Now if I don't implement this, + +1206 +01:06:52,609 --> 01:06:55,276 +what it does is, it looks at this tray collection, says, + +1207 +01:06:55,278 --> 01:06:59,748 +is it horizontally compact? Yes? Then return full screen. + +1208 +01:06:59,750 --> 01:07:01,916 +That's how this whole adaptation thing works. + +1209 +01:07:01,918 --> 01:07:05,387 +Well, I can fix that by just saying return none. Okay, + +1210 +01:07:05,389 --> 01:07:10,191 +that means don't adapt, okay? So now we will never adapt, + +1211 +01:07:10,193 --> 01:07:12,327 +now if I run on the iPhone, + +1212 +01:07:12,329 --> 01:07:16,898 +you'll see that it's not going to adapt because I set + +1213 +01:07:16,900 --> 01:07:20,702 +the presentation style for, adapting style, to be none so + +1214 +01:07:20,704 --> 01:07:24,406 +it's never going to adapt. Go here, you click this. + +1215 +01:07:24,408 --> 01:07:27,809 +Sure enough we get that. Now look how terrible this looks. + +1216 +01:07:27,811 --> 01:07:31,346 +Okay? Clearly horizontally compact is not wide enough to + +1217 +01:07:31,348 --> 01:07:34,849 +show this popover. Okay? It's, smashed it in there, + +1218 +01:07:34,851 --> 01:07:37,986 +tried to obey the 250 point wide for the text field. + +1219 +01:07:37,988 --> 01:07:40,855 +The name and description got cut off. It just not you + +1220 +01:07:40,857 --> 01:07:44,025 +know couldn't quite point to the [LAUGH] the pin prob + +1221 +01:07:44,027 --> 01:07:46,661 +is a big mess. So this is not the solution to this problem. + +1222 +01:07:46,663 --> 01:07:48,797 +It seemed like it would be a good solution to this problem. + +1223 +01:07:48,799 --> 01:07:52,834 +But it's not. So, lets go try and solve some of those other + +1224 +01:07:52,836 --> 01:07:57,405 +problems we had. Okay, one is, we had no done button, okay? + +1225 +01:07:57,407 --> 01:07:59,074 +So how can we get the done button back? Well, + +1226 +01:07:59,076 --> 01:08:01,876 +we need to put that thing back in a navigation controller, + +1227 +01:08:01,878 --> 01:08:06,614 +but only when we're adapting. So, first of all, + +1228 +01:08:06,616 --> 01:08:07,749 +I'm going to comment this out so + +1229 +01:08:07,751 --> 01:08:10,418 +that we're back to adapting. And I'm gonna input another + +1230 +01:08:10,420 --> 01:08:15,423 +delegate method here which is called view controller for + +1231 +01:08:15,425 --> 01:08:20,462 +adaptive presentation style. Here it is. Okay, + +1232 +01:08:20,464 --> 01:08:26,801 +again I'll show you the arguments here. Okay, now look + +1233 +01:08:26,803 --> 01:08:30,505 +what this one returns. This one returns a view controller. + +1234 +01:08:30,507 --> 01:08:33,274 +This is basically saying, okay, I'm trying to adapt + +1235 +01:08:33,276 --> 01:08:36,144 +to a certain style, that's gonna be the full screen style + +1236 +01:08:36,146 --> 01:08:38,880 +here give me a View Controller to show + +1237 +01:08:38,882 --> 01:08:41,916 +when I adapt. Now if I don't implement this, it's just + +1238 +01:08:41,918 --> 01:08:44,452 +going to use the edit waypoint view controller, okay. + +1239 +01:08:44,454 --> 01:08:47,422 +But I'm going to fix this to return a navigational control + +1240 +01:08:47,424 --> 01:08:50,325 +that has an edit waypoint controller in it. Okay. So + +1241 +01:08:50,327 --> 01:08:53,194 +let's do that. I'm going to say, first I'm gonna let, + +1242 +01:08:53,196 --> 01:08:56,831 +well first I'm gonna say, if the style that we're adapting + +1243 +01:08:56,833 --> 01:09:01,569 +to is full screen. Okay, then I'm going to create + +1244 +01:09:01,571 --> 01:09:05,907 +a navigation controller, let navcon equal a UINavigation. + +1245 +01:09:05,909 --> 01:09:09,144 +I'm just creating it with its constructor, right, + +1246 +01:09:09,146 --> 01:09:12,614 +its initializer. And the rootViewController of it is + +1247 +01:09:12,616 --> 01:09:19,187 +going to be the controllers. PresentedViewController, + +1248 +01:09:19,189 --> 01:09:21,723 +remember we used that in the other one, okay, + +1249 +01:09:21,725 --> 01:09:22,423 +that is the EditWaypoint, + +1250 +01:09:22,425 --> 01:09:25,293 +EditWaypointViewController that we're trying to present, + +1251 +01:09:25,295 --> 01:09:28,129 +that's what it is. And so now I'm just gonna return this + +1252 +01:09:28,131 --> 01:09:31,266 +navigation controller instead. So it's gonna use + +1253 +01:09:31,268 --> 01:09:34,369 +the navigation controller instead of this. If we're not + +1254 +01:09:34,371 --> 01:09:36,671 +adapting to full screen then I'm gonna return nil and + +1255 +01:09:36,673 --> 01:09:39,507 +let it do whatever it does by default which is you know + +1256 +01:09:39,509 --> 01:09:43,144 +use the popover or it's not adapting so it doesn't matter. + +1257 +01:09:43,146 --> 01:09:46,214 +All right let's see if that fixes anything here. + +1258 +01:09:51,388 --> 01:09:54,656 +All right here we go. Drop it. Click on it, + +1259 +01:09:54,658 --> 01:09:58,459 +boom. Wahoo! Look at that we have a done button back. + +1260 +01:09:58,461 --> 01:10:00,528 +Now that done button, by the way, you might say, + +1261 +01:10:00,530 --> 01:10:00,762 +where'd that come from? + +1262 +01:10:00,764 --> 01:10:03,598 +Okay, well that's because we put the done button into that + +1263 +01:10:03,600 --> 01:10:06,167 +NBC back when it used to be a navigation controller. + +1264 +01:10:06,169 --> 01:10:09,003 +When we removed the navigation controller it kept the done + +1265 +01:10:09,005 --> 01:10:11,472 +button. It wasn't able to display it because it wasn't + +1266 +01:10:11,474 --> 01:10:14,475 +in a navigation controller until now. Again, but it kept + +1267 +01:10:14,477 --> 01:10:17,412 +the Done button. Remember that all the things that appear + +1268 +01:10:17,414 --> 01:10:19,647 +in a navigation controllers title bar, the buttons and + +1269 +01:10:19,649 --> 01:10:23,384 +stuff are associated with the NBC inside, okay. And + +1270 +01:10:23,386 --> 01:10:25,920 +when you remove, put something in, embed in, or + +1271 +01:10:25,922 --> 01:10:28,056 +take out of a navigational controller in NBC, + +1272 +01:10:28,058 --> 01:10:30,892 +it keeps all it's things so that's why we kept the Done + +1273 +01:10:30,894 --> 01:10:33,228 +button. Okay, not only kept the Done button there, + +1274 +01:10:33,230 --> 01:10:34,829 +it's still going to unwind. Okay? + +1275 +01:10:34,831 --> 01:10:37,565 +Cuz it's still hooked up to that to unwind there. Now, + +1276 +01:10:37,567 --> 01:10:40,702 +we still have this black background. That's not so + +1277 +01:10:40,704 --> 01:10:43,137 +good. Okay? How are we gonna fix that? Well, + +1278 +01:10:43,139 --> 01:10:46,174 +I'm gonna do that in a cool way, which is to stop + +1279 +01:10:46,176 --> 01:10:51,079 +having it basically cover up the the thing underneath, and + +1280 +01:10:51,081 --> 01:10:52,747 +let it show through. Okay? + +1281 +01:10:52,749 --> 01:10:56,451 +I'm gonna have this modal view controller come up. But + +1282 +01:10:56,453 --> 01:10:59,220 +not cover up what's behind, okay, and + +1283 +01:10:59,222 --> 01:11:01,756 +that's really simple to do. Actually, + +1284 +01:11:01,758 --> 01:11:04,959 +we're going to use the same method we did back here, okay, + +1285 +01:11:04,961 --> 01:11:07,929 +but instead of saying return none, okay, + +1286 +01:11:07,931 --> 01:11:12,700 +we're just going to say let's just return. If the trace + +1287 +01:11:12,702 --> 01:11:18,139 +collection here collection, okay trait selection, + +1288 +01:11:18,141 --> 01:11:22,644 +horizontal size class, equals compact, then we're gonna + +1289 +01:11:22,646 --> 01:11:26,881 +return this new style which is over full screen. + +1290 +01:11:26,883 --> 01:11:28,549 +So over full screen is like full screen but + +1291 +01:11:28,551 --> 01:11:31,919 +it's over the things so the things shines through. Okay + +1292 +01:11:31,921 --> 01:11:33,588 +that's the only difference between full screen and + +1293 +01:11:33,590 --> 01:11:38,126 +over full screen. Otherwise, we're just going to not adapt. + +1294 +01:11:38,128 --> 01:11:40,762 +Okay, we're only gonna adapt in the horizontalSizeClass + +1295 +01:11:40,764 --> 01:11:45,466 +Compact. Okay, so let's see what that looks like. + +1296 +01:11:51,074 --> 01:11:56,044 +All right, here it is. Drop one, click, bring it up. + +1297 +01:11:56,046 --> 01:12:00,114 +All right! Okay, it brought it up. But, it's kinda weird that + +1298 +01:12:00,116 --> 01:12:02,950 +we can see all the way through it kinda makes it think that + +1299 +01:12:02,952 --> 01:12:06,521 +we could click on this things. Also having the word + +1300 +01:12:06,523 --> 01:12:09,123 +description be on the dark background makes it hard to + +1301 +01:12:09,125 --> 01:12:13,895 +see it. Okay. I also noticed that maybe our 250 is a little + +1302 +01:12:13,897 --> 01:12:17,598 +too wide of a minimum. Maybe we wanna go down to 200. + +1303 +01:12:17,600 --> 01:12:19,734 +But, what were really cool is if we could actually show + +1304 +01:12:19,736 --> 01:12:23,137 +what's behind slightly blurred. Just like the popover + +1305 +01:12:23,139 --> 01:12:26,641 +one does. Right? The popover one it showed the name and + +1306 +01:12:26,643 --> 01:12:29,844 +description, but it was only kinda the slightly see-through + +1307 +01:12:29,846 --> 01:12:31,612 +semi-transparent blurred thing. + +1308 +01:12:31,614 --> 01:12:34,449 +Well we can do that ourselves. Okay? There's a view, okay, + +1309 +01:12:34,451 --> 01:12:37,418 +we can talk about in the slides. But there's a view + +1310 +01:12:37,420 --> 01:12:42,457 +which essentially presents whatever's behind it blurred + +1311 +01:12:42,459 --> 01:12:45,626 +okay, tha's what the view does. so were gonna poke one + +1312 +01:12:45,628 --> 01:12:49,764 +of this views right at the top of the navigation controllers + +1313 +01:12:49,766 --> 01:12:52,533 +view hierarchy okay. Even behind the things + +1314 +01:12:52,535 --> 01:12:55,036 +like this bar at the top of the navigation control + +1315 +01:12:55,038 --> 01:12:57,705 +everything. Okay, we're gonna be really right at the top, so + +1316 +01:12:57,707 --> 01:12:58,773 +it's gonna blur everything behind. And + +1317 +01:12:58,775 --> 01:13:01,109 +the navigation controller's gonna be on top of this nice, + +1318 +01:13:01,111 --> 01:13:04,746 +blurred thing. Okay? So, how do we do that? Well, + +1319 +01:13:04,748 --> 01:13:07,281 +we create that navigation controller right here. So + +1320 +01:13:07,283 --> 01:13:10,218 +all we need to do is to create this little blurring view + +1321 +01:13:10,220 --> 01:13:15,890 +doohickey, which is called a visual effects view. And + +1322 +01:13:15,892 --> 01:13:19,594 +also, by the way, we're gonna wanna put here if the style + +1323 +01:13:19,596 --> 01:13:24,365 +is OverFullScreen so that we can do it in both cases there. + +1324 +01:13:24,768 --> 01:13:27,068 +So, we're gonna create a visual effects view, + +1325 +01:13:27,070 --> 01:13:30,938 +visualEffectsView, we'll call it and + +1326 +01:13:30,940 --> 01:13:31,973 +it's UIVisualEffectView. + +1327 +01:13:31,975 --> 01:13:38,246 +That's the name of the class. VisualEffectView. I guess + +1328 +01:13:38,248 --> 01:13:42,083 +it would be VisualEffectView cuz it's a single effect. And + +1329 +01:13:42,085 --> 01:13:46,587 +you just specify what kind of effect you want. Effect, and + +1330 +01:13:46,589 --> 01:13:51,392 +I want a UIBlurEffect. And the style of + +1331 +01:13:51,394 --> 01:13:54,695 +it is I want a ExtraLight okay which is a really + +1332 +01:13:54,697 --> 01:13:57,965 +extra light ver, blur. And the reason I want extra light is + +1333 +01:13:57,967 --> 01:13:59,801 +cuz I'm gonna be putting black text on top of it and + +1334 +01:13:59,803 --> 01:14:02,670 +things like that so I really want that to stand out. So + +1335 +01:14:02,672 --> 01:14:05,139 +there's extra light blurring. + +1336 +01:14:05,141 --> 01:14:10,445 +Now I'm going to set the visual effects views frame + +1337 +01:14:11,247 --> 01:14:14,482 +to equal the navCon bounds. Okay. + +1338 +01:14:14,484 --> 01:14:16,150 +So navCon is a view controller. It's just + +1339 +01:14:16,152 --> 01:14:17,919 +a regular view controller like any other view controller. + +1340 +01:14:17,921 --> 01:14:20,621 +It's got a view which is it's top level view. So I'm gonna + +1341 +01:14:20,623 --> 01:14:23,991 +put my visual effects right at the top of its hierarchy, so + +1342 +01:14:23,993 --> 01:14:25,893 +I'm gonna have it fill the entire thing. Now, + +1343 +01:14:25,895 --> 01:14:28,296 +I'm also gonna do a little bit of magic here which we didn't + +1344 +01:14:28,298 --> 01:14:30,164 +talk about at all, which is, there's + +1345 +01:14:30,166 --> 01:14:33,734 +a really kind of an old style way of doing auto layout where + +1346 +01:14:33,736 --> 01:14:36,604 +you can specify just a couple of things. + +1347 +01:14:36,606 --> 01:14:40,608 +And, I'm going to have this visual effect view + +1348 +01:14:40,610 --> 01:14:44,445 +always stick to the same size as the nab cons bounds. + +1349 +01:14:44,447 --> 01:14:47,315 +And the way I'm gonna do it, is by using these old style + +1350 +01:14:47,317 --> 01:14:51,018 +constraints where I basically say that the width and height + +1351 +01:14:51,020 --> 01:14:55,122 +of my visual effects view is flexible. So, as things change + +1352 +01:14:55,124 --> 01:14:57,859 +it tries to stick to its super view. Okay? Don't worry + +1353 +01:14:57,861 --> 01:15:00,628 +too much about this magic It's just a little easier way than + +1354 +01:15:00,630 --> 01:15:03,965 +doing this than trying to show you how to do it with + +1355 +01:15:03,967 --> 01:15:05,166 +the new way. + +1356 +01:15:05,168 --> 01:15:08,870 +So I just basically say that's auto resizing math is flexible + +1357 +01:15:08,872 --> 01:15:09,203 +width and flexible height. + +1358 +01:15:09,205 --> 01:15:13,374 +If it's superview changes it's size than it sizes with it, + +1359 +01:15:13,376 --> 01:15:15,443 +using the rules keep your width and + +1360 +01:15:15,445 --> 01:15:16,544 +height flexible. Okay? + +1361 +01:15:16,546 --> 01:15:20,815 +So now I'm just going to take that navcon top level view and + +1362 +01:15:20,817 --> 01:15:23,551 +insert a subview, which is a visual effects view. + +1363 +01:15:23,553 --> 01:15:28,189 +And I'm gonna put it at index zero, which is all the way at + +1364 +01:15:28,191 --> 01:15:31,359 +the back. Remember subviews is ordered int he subview list. + +1365 +01:15:31,361 --> 01:15:34,762 +All right, so let's take a look at that. + +1366 +01:15:39,936 --> 01:15:45,473 +All right. Drop it here. Up. There we go. + +1367 +01:15:45,475 --> 01:15:48,209 +Okay, see how it, you can kinda see the, + +1368 +01:15:48,211 --> 01:15:51,012 +I don't know how, how good the projection there is, but + +1369 +01:15:51,014 --> 01:15:52,513 +you can kinda almost see the valleys here. + +1370 +01:15:52,515 --> 01:15:55,783 +The mountains and the valleys. In there. When you get this + +1371 +01:15:55,785 --> 01:16:01,455 +we'll go run it at home you'll see it a lot clearer. Okay? So + +1372 +01:16:01,457 --> 01:16:03,024 +that's it we only have three minutes so + +1373 +01:16:03,026 --> 01:16:08,963 +I'm not going to the slides on that. I will post on + +1374 +01:16:08,965 --> 01:16:12,533 +how you can learn a little more about that. And + +1375 +01:16:12,535 --> 01:16:14,435 +that's it. So, that's everything there. + +1376 +01:16:14,437 --> 01:16:15,903 +You learned a lot about map view and + +1377 +01:16:15,905 --> 01:16:17,572 +about all kinds of segways there, so + +1378 +01:16:17,574 --> 01:16:18,773 +hopefully that will prepare you for + +1379 +01:16:18,775 --> 01:16:20,708 +your final presentation. So, + +1380 +01:16:20,710 --> 01:16:22,343 +next week is just the alternate final, + +1381 +01:16:22,345 --> 01:16:24,445 +there's a holiday on Monday, so there's no class then, + +1382 +01:16:24,447 --> 01:16:26,747 +and Wednesday is the alternate final. And, + +1383 +01:16:26,749 --> 01:16:30,718 +if you have any questions I'll help you here as usual. For + +1384 +01:16:30,720 --> 01:16:30,751 +more, please visit us at stanford.edu. + From ddbcb30e06c8a8d9c00b5c7860e6685345ee4186 Mon Sep 17 00:00:00 2001 From: TangJR Date: Sun, 24 Jul 2016 23:13:10 +0800 Subject: [PATCH 03/23] translate to 160 --- .../8. Multithreading and Text Field.srt | 160 ++++++++++++++++++ 1 file changed, 160 insertions(+) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index 63e51d5..670e586 100644 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -5,643 +5,803 @@ 2 00:00:03,804 --> 00:00:08,040 Standford University. >> All right, +斯坦福大学 3 00:00:08,042 --> 00:00:13,746 welcome then to lecture number eight. I think it's eight, +欢迎参加第八讲。好像是第八讲。 4 00:00:13,748 --> 00:00:18,083 yes, of CS193P Spring of 2016. So today, we start off +是的，2016 春季 CS193P 课程。今天，我们将 5 00:00:18,085 --> 00:00:21,020 by continuing that demo that we were doing last time. +继续完成上一次的 demo 6 00:00:21,022 --> 00:00:24,423 Remember we had the demo, Cassini demo with the, scroll +今天用到之前 scroll view 写的 Cassini 7 00:00:24,425 --> 00:00:27,693 view in there. And so I'm gonna make it more powerful, +让它功能更加强大. 8 00:00:27,695 --> 00:00:30,262 we're gonna get multiple MVCs going in there. +我们将会用到多个 MVC 的结构. 9 00:00:30,264 --> 00:00:34,533 We'll start doing some zooming in the scroll view. +会用到 scroll view 的缩放属性. 10 00:00:34,535 --> 00:00:37,703 Depending on how the time goes I might actually show you some +如果有时间，我会通过实际案例来 11 00:00:37,705 --> 00:00:40,406 things that couple of you have asked about on Piazza. +解答有些同学对 Piazza 项目的疑问. 12 00:00:40,408 --> 00:00:44,009 Like, how to when I launch my calculator app can I have it +例如，在启动我的计算器 app 的时候， 13 00:00:44,011 --> 00:00:46,311 not launch and show a blank graph, right, +因为没有启动图而显示空白的情况. 14 00:00:46,313 --> 00:00:49,314 how can I have it launch and show the calculator for +怎样才能在在第一次启动计算器时， 15 00:00:49,316 --> 00:00:52,651 the very first time, okay, those kinds of things. +显示启动页等，诸如此类的问题. 16 00:00:52,653 --> 00:00:53,652 So we'll see how the time goes and +最后，我们会根据时间安排 17 00:00:53,654 --> 00:00:56,121 decide on the fly whether to do that stuff. +来决定是否要解答这些. 18 00:00:56,123 --> 00:00:57,623 Then we're gonna dive back into the slides. +让我们回到幻灯片上. 19 00:00:57,625 --> 00:00:59,358 I'm gonna talk about multi-threading, okay? +我之后还会讲到多线程. 20 00:00:59,360 --> 00:01:04,029 Very, very important thing in iOS is how to multithread +在 iOS 上，多线程的处理是非常非常重要的内容. 21 00:01:04,031 --> 00:01:06,799 your execution. And then I'll go back to the demo, and +然后我们会回到 Cassini demo, 22 00:01:06,801 --> 00:01:10,436 we'll multithread this Cassini thing we're working on, okay? +为它加上多线程支持. 23 00:01:10,438 --> 00:01:12,104 And then time permitting at the end I'll go back to +在时间允许的情况下, 最后还会回到幻灯片 24 00:01:12,106 --> 00:01:14,673 the slides and I'm gonna talk about text fields. And +讲一下 text field. 然后 25 00:01:14,675 --> 00:01:19,511 then, next week we have table views, databases, etc. And +下周会讲 table view，database 等内容. 26 00:01:19,513 --> 00:01:21,947 again, remember, no assignment going out today. +今天不会布置作业. 27 00:01:21,949 --> 00:01:24,283 The assignment is gonna be a table view based thing, so +作业是基于 table view 的, 28 00:01:24,285 --> 00:01:27,986 it will go out after Monday's lecture, all right? So, +所以我们会在下周一课程之后再布置, 没问题吧. 29 00:01:27,988 --> 00:01:30,589 let's dive back into this Cassini demo. Okay, +那么, 让我们回到 Cassini demo. 30 00:01:30,591 --> 00:01:36,762 we'll start off just exactly where we left off before. So +接着上一次的内容继续完善. 31 00:01:36,764 --> 00:01:41,100 we'll go to Xcode here. So I'm just gonna open Cassini, +启动 Xcode, 打开 Cassini 32 00:01:41,102 --> 00:01:42,868 here it is. I'm just gonna run it real quick just +我先来带大家快速过一遍 33 00:01:42,870 --> 00:01:47,139 to remind you where we were for those with short memories. +回忆下之前的内容. 34 00:01:47,141 --> 00:01:53,812 Even though it's only two days ago. All right, +虽然是两天前才讲的. 35 00:01:53,814 --> 00:01:56,915 here it is. So we've got, our image view, right? +好的, 我们有一个 image view. 36 00:01:56,917 --> 00:02:00,285 We have an ImageView and it's inside a UIScrollView, and so +这个 ImageView 嵌套在 UIScrollView 中, 37 00:02:00,287 --> 00:02:03,922 we're able to scroll around, okay, just by panning with our +所以我们可以进行滚动, 用手指滑动就行 38 00:02:03,924 --> 00:02:06,291 finger. My mouse is like a finger there, so +这光标就是手指 39 00:02:06,293 --> 00:02:10,262 I'm just panning around, and that's all we can do, okay? +目前就只能随意滑动 40 00:02:10,264 --> 00:02:11,997 But we've created this nice UI, or +但是我们这个漂亮的界面 41 00:02:11,999 --> 00:02:15,734 this nice ImageViewController, which is an MVC that lets you +或者说, 漂亮的 ImageViewController 所用的 MVC 模式, 42 00:02:15,736 --> 00:02:19,371 take any image and put it on screen inside the scroll view, +能任意将图片加入到 scroll view 中, 并显示出来 43 00:02:19,373 --> 00:02:23,108 that's kind of a nice reusable, reusable MVC, right? +有很好的重用性, 重用 MVC, 对吧 44 00:02:23,110 --> 00:02:26,378 So now we're going to make this a multi-MVC app, okay, +接下来, 我们会做一个多 MVC 的 app 45 00:02:26,380 --> 00:02:28,213 and I'm gonna reuse this ImageViewController +重用的 ImageViewController 46 00:02:28,215 --> 00:02:31,450 as one of the MVCs. So let's go right to our storyboard, +也是其中之一. 让我们打开 storyboard. 47 00:02:31,452 --> 00:02:32,117 see what this is gonna look like. +来看看里面都有什么内容 48 00:02:32,119 --> 00:02:34,419 This is where the Cassini part of this whole thing is gonna +Cassini 所展示的内容都从这里得到. 49 00:02:34,421 --> 00:02:37,589 come in. All right, I'm gonna create a new View Controller, +现在, 我准备创建一个新的 View Controller 50 00:02:37,591 --> 00:02:39,224 just gonna drag it out right here. Again, +将它拖到这里就可以了 51 00:02:39,226 --> 00:02:41,693 I'm gonna go fairly quickly, cuz I've done this all before, +之前我们已经做过了, 所以这一步操作有点快 52 00:02:41,695 --> 00:02:44,630 so this is almost like a review, for you here. +更像是在帮大家复习 53 00:02:44,632 --> 00:02:45,397 So, I have this controller. +好, controller 创建好了 54 00:02:45,399 --> 00:02:48,700 It needs to have a custom subclass of UIViewController +因为需要自定义 UIViewController 55 00:02:48,702 --> 00:02:51,904 so I'm going to create such a thing. Go here to New File, +所以要做接下来的这些操作. 创建一个新文件 56 00:02:51,906 --> 00:02:55,274 it's iOS source, it's a Cocoa Touch Class. Cuz it's +选择 iOS source, Cocoa Touch Class, 因为 57 00:02:55,276 --> 00:02:58,210 a subclass of an iOS class, which is a UIViewController in +要子类化的类属于 iOS, 这里是 UIViewController 58 00:02:58,212 --> 00:03:01,647 this case. I'm going to call this CassiniViewController, +类名就叫 CassiniViewController 吧 59 00:03:01,649 --> 00:03:04,149 cuz it's gonna let us look at some Cassini images. +这个类会展示更多 Cassini 的图片 60 00:03:04,151 --> 00:03:08,587 That's what our app is gonna do. But just in the same place +也是这个 app 的需求. 存放路径和之前一样 61 00:03:08,589 --> 00:03:11,523 as always here is our CassiniViewController, +CassiniViewController 创建好了 62 00:03:11,525 --> 00:03:15,327 I'm gonna remove the view controller lifecycle methods +暂时先删除模板给出的 view controller 63 00:03:15,329 --> 00:03:18,630 that it gives me right here just for now anyway. +生命周期方法 64 00:03:18,632 --> 00:03:22,067 And I'm actually gonna uncomment this prepareForSegue +然后打开 prepareForSegue 的注释 65 00:03:22,069 --> 00:03:24,002 because my CassiniViewController is +因为 CassiniViewController 会 66 00:03:24,004 --> 00:03:27,005 definitely going to be doing, some segueing. +用到这个方法, 一些 segue 67 00:03:27,007 --> 00:03:29,341 So let's now go back to our storyboard, +现在让我们回到 storyboard 68 00:03:29,343 --> 00:03:32,744 now that we have this ImageViewController class, and +我们已经有了 ImageViewController 69 00:03:32,746 --> 00:03:36,315 I'm gonna change the class of this controller right here +再通过 identity inspector, 将这个 70 00:03:36,317 --> 00:03:40,452 with the identity inspector, to be a CassiniViewController, +controller 改为 CassiniViewController 71 00:03:40,454 --> 00:03:45,724 okay. Everybody got that? I'm going to put this whole +好的, 都能跟上吧? 接下来, 我会将整个 72 00:03:45,726 --> 00:03:49,494 MVC structure into that split view with navigation that's +MVC 结构装到 split view 中 73 00:03:49,496 --> 00:03:52,331 over in there, the thing that will work in both iPad and +这样就能同时用 iPad 和 74 00:03:52,333 --> 00:03:55,300 iPhone, exact same thing we did for, +iPhone 上, 这种处理方式我们在 75 00:03:55,302 --> 00:03:57,869 the emotions view controller. So, let's do that. +emotions view controller 上也做过. 下面来实现吧. 76 00:03:57,871 --> 00:04:00,939 I'm going to start by dragging out the split view controller, +接下来需要拖一个 split view controller 77 00:04:00,941 --> 00:04:02,007 I'm gonna zoom way out here. +先缩小画板 78 00:04:02,009 --> 00:04:04,810 Let's go get a Split View Controller, here it is. I'll +然后找到 Split View Controller 79 00:04:04,812 --> 00:04:09,781 drag it out. I'll get rid of these extra things that came +拖拽出来. 删掉除了 80 00:04:09,783 --> 00:04:12,551 along here with the Split View Controller because I already +Split View Controller 的其他内容, 因为我们已经 81 00:04:12,553 --> 00:04:15,153 have my master and detail right here. The Cassini's +有自己的 master 和 detail 了. Cassini 是 82 00:04:15,155 --> 00:04:17,956 gonna be my master and this ImageViewController's gonna be +master, ImageViewController 是 detail. 83 00:04:17,958 --> 00:04:21,260 my detail right there. So I'm just gonna Control drag, hook +按住 Control 并拖拽到 master 84 00:04:21,262 --> 00:04:25,197 up my master. And a Control drag, hook up my detail. +然后按住 Control 并拖拽到 detail 85 00:04:25,199 --> 00:04:28,400 I'm also gonna take my little entry arrow and make it so +接下来, 将入口箭头移动到 86 00:04:28,402 --> 00:04:31,136 that it enters on the Split View Controller. Right, +Split View Controller 87 00:04:31,138 --> 00:04:32,738 instead of entering on my Image View Controller, +Image View Controller 不再是入口 88 00:04:32,740 --> 00:04:37,376 obviously. And, I want this to work on both iPhone and iPad, +我想要在 iPhone 和 iPad 上使用 89 00:04:37,378 --> 00:04:41,013 so I'm gonna take my master and put it embedded inside +所以, 我准备将 master 嵌入到 90 00:04:41,015 --> 00:04:45,917 of a navigation controller, okay? And maybe I can even go +navigation controller 中, 然后我能在这 91 00:04:45,919 --> 00:04:50,589 in here and put a nice title here, right here. Cassini, +给它加上 title. Cassini. 92 00:04:50,591 --> 00:04:54,626 okay? All right now, what is this UI going to do? +跟上了吗? 最终, 这个界面到底有什么作用? 93 00:04:54,628 --> 00:04:57,029 What's it going to look like? How's it gonna function? +长什么样呢? 怎样触发一些功能? 94 00:04:57,031 --> 00:04:59,598 Well, I'm just gonna have three buttons here. +好的, 我会在这里放 3 个按钮 95 00:04:59,600 --> 00:05:01,500 Similar to how I had in emotions view controller. +和之前的 emotions view controller 很像 96 00:05:01,502 --> 00:05:04,102 In a demo I can only do, I can't do a nice complicated +在 demo 中也只能这样了, 不能像计算器 97 00:05:04,104 --> 00:05:07,172 MVC like a calculator and then another complicated one like +一样有复杂的 MVC 结构, 也不能像 98 00:05:07,174 --> 00:05:09,808 a graph view. I have to do a simple one. So I'm gonna do +graph view 那样复杂. 只能做个简单的界面了. 所以我也只好 99 00:05:09,810 --> 00:05:11,877 a simple one here. Where I'm gonna put three buttons and +这样了. 之所以我要放三个按钮, 100 00:05:11,879 --> 00:05:15,180 those three buttons are just going to cause three different +是因为要展示三张 101 00:05:15,182 --> 00:05:20,285 images from NASA, okay, about Cassini which is a little +NASA 的图片. 至于 Cassini, 它是被 102 00:05:20,287 --> 00:05:22,988 thing sent out into space to take pictures. I'm gonna put +发送到太空来拍摄图片的. 我会把 103 00:05:22,990 --> 00:05:25,223 those three buttons here and then were just gonna segue, +三个按钮放到这, 然后我们处理 segue, 104 00:05:25,225 --> 00:05:27,826 as we know how to do, down to here, +大家应该知道怎么做. 将 ImageViewController 105 00:05:27,828 --> 00:05:29,194 which is gonna be our ImageViewController, +放到下面来 106 00:05:29,196 --> 00:05:30,662 all right. So the Image View Controller's just gonna show +Image View Controller 会用来显示图片 107 00:05:30,664 --> 00:05:33,065 the image, and we already know that the Image View Controller +我们已经知道展示图片的 Image View Controller 是一个 108 00:05:33,067 --> 00:05:35,901 is a nice, little, reasonable MVC that shows an image. +优雅的, 小巧的, 合理的 MVC 结构. 109 00:05:35,903 --> 00:05:37,836 So it's perfect, exactly what I want. So +如此完美, 正是我们想要的 110 00:05:37,838 --> 00:05:39,871 I'm gonna go down here and get the buttons. So it's this +向下滚动, 找到按钮. 111 00:05:39,873 --> 00:05:44,343 button right here. Let's go ahead and make it bigger, +将按钮放在这. 继续, 把它放大点, 112 00:05:44,345 --> 00:05:48,580 I'll say 40 point would be a pretty good size here. +设置为 40 点看起来比较好 113 00:05:48,582 --> 00:05:52,417 And, make three of them, copy, paste so +然后创建三个这样按钮, 复制, 粘贴 114 00:05:52,419 --> 00:05:56,154 I get that. Okay, one of them is gonna be called Earth, +好了, 一个叫做 Earth 115 00:05:56,156 --> 00:05:59,291 another one is gonna be called Cassini. +一个叫做 Cassini. 116 00:05:59,293 --> 00:06:02,194 And another one is gonna be called Saturn, okay? +剩下的一个叫 Saturn, 好了吗? 117 00:06:02,196 --> 00:06:04,262 And then I'm just gonna take these three things. +然后, 将这三个按钮 118 00:06:04,264 --> 00:06:06,031 Of course it put them in a stack view. +放到 stack view 中 119 00:06:06,033 --> 00:06:11,903 Okay, we'll go ahead and have the stack view be fill. +ok, 将 stack view 对齐方式设置为 fill. 120 00:06:11,905 --> 00:06:13,338 And we'll also do again fill equally. +然后将分布设置为 fill equally. 121 00:06:13,340 --> 00:06:15,474 It doesn't really matter because they're all identical, +这些都无关紧要, 它们都是相同的 122 00:06:15,476 --> 00:06:17,909 they're all buttons. We'll put a little spacing in there, +都是按钮. 然后给它们加一些间隙 123 00:06:17,911 --> 00:06:21,179 maybe. 20 points something like that. Then I'm gonna drag +20 点之类的. 接下来将它拖到 124 00:06:21,181 --> 00:06:24,082 this into the middle use my blue lines right there so that +视图中间, 有蓝色对齐线这里 125 00:06:24,084 --> 00:06:27,152 I can go here and say Reset to suggested constraints. +点击这里, 选择 Reset to suggested constraints (重置为建议约束). 126 00:06:27,154 --> 00:06:29,588 And then I'm gonna go over to my size inspector and +接着看到 size inspector 127 00:06:29,590 --> 00:06:32,224 double check that it did the kind of constraints I want. +再次确认约束是否正确添加 128 00:06:32,226 --> 00:06:35,227 Which that looks good to me it's gonna align these things +看来这些约束能正确将 129 00:06:35,229 --> 00:06:39,030 in the center, okay? So, here's our UI right here. +视图居中, 好了吗? 这就是我们的 UI 了. 130 00:06:39,032 --> 00:06:43,802 Now, all we need to do is have these three things segue down +现在, 就只需要将这三个按钮的事件和下面 131 00:06:43,804 --> 00:06:47,472 to here to fill these images. Now, I'll show you where these +这个关联, 来显示图片了. 之后, 我会展示这些 132 00:06:47,474 --> 00:06:49,841 images come from in a minute here, but let's just create +图片从哪来, 现在先来创建 segue. 133 00:06:49,843 --> 00:06:52,110 the segue. Now, I'm gonna do something a little different +这次我们处理 segue 的方式和之前不一样. 134 00:06:52,112 --> 00:06:55,847 with this segue. In our last one I, each segue had +之前, 每个 segue 都有 135 00:06:55,849 --> 00:06:57,816 its own identifier that was different, and +自己的 identifier, 每一个都不同 136 00:06:57,818 --> 00:07:00,619 it was the identifier that let us know which emotion to +这些 identifier 使我们知道应该 137 00:07:00,621 --> 00:07:03,488 show in the emotions one. Here I'm gonna have them all have +显示哪个表情. 这一次, 它们只有 138 00:07:03,490 --> 00:07:06,591 the same identifier, and I'm gonna use the title of +一个相同的 identifier, 我将使用按钮的 title 139 00:07:06,593 --> 00:07:09,628 the button to decide which image, okay? So it's kind of +来决定显示的图片. 所以, 140 00:07:09,630 --> 00:07:11,897 a cross between what we did in the calculator and +这和我们之前做计算器, 141 00:07:11,899 --> 00:07:14,666 what we did in emotions, all right? So, let's go ahead and +做表情的处理不一样. 142 00:07:14,668 --> 00:07:17,969 create these things. So, I'm gonna, Control drag, okay, +下面我们来创建 segue 吧. 按钮 Contorl 并拖拽, 143 00:07:17,971 --> 00:07:21,540 from Saturn down to here. This is in a split view, right, +从 Saturn 到这里. 他们都在 split view 中. 144 00:07:21,542 --> 00:07:22,374 so I'm gonna do Show Detail, right? +选择 Show Detail. 145 00:07:22,376 --> 00:07:25,143 That's the kind of segue I want, not show. The same thing +这才是我想要的 segue, 而不是 Show. 146 00:07:25,145 --> 00:07:29,514 with Cassini right here, Show Detail. And then up here to +Cassini 也是同样, ShowDetail. 接着是 147 00:07:29,516 --> 00:07:34,486 Earth, Show Detail. Whoops, not Present Modally, undo, +Earch, Show Detail. 噢, 不是 Present Modally, 撤销, 148 00:07:34,488 --> 00:07:38,990 let's try that again. Show Detail. Okay, so +重新来一次, Show Detail. 149 00:07:38,992 --> 00:07:41,092 we've got these three things here. Let's go ahead and +这三个就关联好了. 然后来检查下. 150 00:07:41,094 --> 00:07:43,662 inspect them. I'm gonna put an identifier on them but +我准备给它们设置 identifier, 但 151 00:07:43,664 --> 00:07:45,163 they're all gonna have the same identifier. +它们的 identifier 都相同. 152 00:07:45,165 --> 00:07:48,266 And what that means is when prepareForSegue gets called, +那么, 这在调用 prepareForSegue 时意味着什么呢 153 00:07:48,268 --> 00:07:51,169 it's gonna be called, and the same thing is gonna happen for +调用时, 他们所触发的事件都是相同的. 154 00:07:51,171 --> 00:07:53,505 each one. Again I'm gonna look at the sender in +不过, 可以通过 155 00:07:53,507 --> 00:07:54,706 prepareForSegue to know which button, +prepareForSegue 的 sender 来区别按钮, 156 00:07:54,708 --> 00:07:57,175 but we're gonna use the same code. So I'm gonna call this +但是它们的代码是共用的. 所以, 就命名为 157 00:07:57,177 --> 00:08:00,345 Show Image, cuz that's what it does, okay, when you click On +Show Image 吧, 见名知意. 158 00:08:00,347 --> 00:08:03,381 here to segue, it segues to this image view controller and +点击 Segue, 跳转到 image view controller 159 00:08:03,383 --> 00:08:06,585 shows an image. Okay, so let's make sure all three of +显示图片. 确保三个按钮都 160 00:08:06,587 --> 00:08:10,755 them are doing that. Okay, so everybody cool with this? +设置好. 好了, 大家对这一步有疑问吗? 161 00:08:10,757 --> 00:08:14,092 This is all just review, I haven't done anything new, yet + 162 00:08:14,094 --> 00:08:17,829 here. K, now of course we know if we want these From 6fb6c715ee5ad7e4cb1c73d5c878ff50b50f6e5a Mon Sep 17 00:00:00 2001 From: saitjr Date: Mon, 15 Aug 2016 22:56:12 +0800 Subject: [PATCH 04/23] 168~270 --- README.md | 0 ... Introduction to iOS, Xcode, and Swift.srt | 0 subtitles/10. Core Data.srt | 0 subtitles/11. Core Data Demo.srt | 0 subtitles/13. NSTimer and Animation.srt | 0 subtitles/14. Animation and Core Motion.srt | 0 ...pplication Lifecycle, Alerts, CloudKit.srt | 0 subtitles/16. Notifications and CloudKit.srt | 0 .../17. Segues, Core Location, and MapKit.srt | 0 subtitles/18. Persistence.srt | 0 subtitles/2. Applying MVC.srt | 0 ...3. More Swift and Foundation Framework.srt | 0 subtitles/4. Views.srt | 0 ...ontroller, Gestures, and Multiple MVCs.srt | 0 ... FaceIt, and View Controller Lifecycle.srt | 0 ... Protocols, Delegation, and ScrollView.srt | 0 .../8. Multithreading and Text Field.srt | 112 +++++++++++++++++- subtitles/9. Table View.srt | 0 18 files changed, 110 insertions(+), 2 deletions(-) mode change 100644 => 100755 README.md mode change 100644 => 100755 subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt mode change 100644 => 100755 subtitles/10. Core Data.srt mode change 100644 => 100755 subtitles/11. Core Data Demo.srt mode change 100644 => 100755 subtitles/13. NSTimer and Animation.srt mode change 100644 => 100755 subtitles/14. Animation and Core Motion.srt mode change 100644 => 100755 subtitles/15. Application Lifecycle, Alerts, CloudKit.srt mode change 100644 => 100755 subtitles/16. Notifications and CloudKit.srt mode change 100644 => 100755 subtitles/17. Segues, Core Location, and MapKit.srt mode change 100644 => 100755 subtitles/18. Persistence.srt mode change 100644 => 100755 subtitles/2. Applying MVC.srt mode change 100644 => 100755 subtitles/3. More Swift and Foundation Framework.srt mode change 100644 => 100755 subtitles/4. Views.srt mode change 100644 => 100755 subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt mode change 100644 => 100755 subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt mode change 100644 => 100755 subtitles/7. Closures, Extensions, Protocols, Delegation, and ScrollView.srt mode change 100644 => 100755 subtitles/8. Multithreading and Text Field.srt mode change 100644 => 100755 subtitles/9. Table View.srt diff --git a/README.md b/README.md old mode 100644 new mode 100755 diff --git a/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt b/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt old mode 100644 new mode 100755 diff --git a/subtitles/10. Core Data.srt b/subtitles/10. Core Data.srt old mode 100644 new mode 100755 diff --git a/subtitles/11. Core Data Demo.srt b/subtitles/11. Core Data Demo.srt old mode 100644 new mode 100755 diff --git a/subtitles/13. 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More Swift and Foundation Framework.srt old mode 100644 new mode 100755 diff --git a/subtitles/4. Views.srt b/subtitles/4. Views.srt old mode 100644 new mode 100755 diff --git a/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt b/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt old mode 100644 new mode 100755 diff --git a/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt b/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt old mode 100644 new mode 100755 diff --git a/subtitles/7. Closures, Extensions, Protocols, Delegation, and ScrollView.srt b/subtitles/7. Closures, Extensions, Protocols, Delegation, and ScrollView.srt old mode 100644 new mode 100755 diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt old mode 100644 new mode 100755 index 670e586..3061ba8 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -800,439 +800,547 @@ them are doing that. Okay, so everybody cool with this? 161 00:08:10,757 --> 00:08:14,092 This is all just review, I haven't done anything new, yet - +以上是对之前的回顾，还没添加新的知识点 162 00:08:14,094 --> 00:08:17,829 here. K, now of course we know if we want these +如果想要这些 segue 生效 163 00:08:17,831 --> 00:08:21,366 little segues here to work, we need to prepare them, so +还需要准备 segue 164 00:08:21,368 --> 00:08:25,003 let's go back to our Cassini View Controller right here and +接下来回到 Cassini View Controller， 165 00:08:25,005 --> 00:08:27,973 do our prepare for segue. I'm gonna show you something +准备 segue. 接下来我会演示如何 166 00:08:27,975 --> 00:08:31,109 that's kind of nice to do from a clean coding mechanism, +在用纯代码来实现 167 00:08:31,111 --> 00:08:35,747 which is I like to create a private struct here to +我比较喜欢创建一个私有 struct 168 00:08:35,749 --> 00:08:38,750 store my constants that are strings in the storyboard. +来存放 storyboard 中 string 类型的常量 169 00:08:38,752 --> 00:08:42,754 So I usually call this thing storyboard okay? And then I +所以命名为 storyboard 170 00:08:42,756 --> 00:08:47,225 just put these static lets inside. So the ShowImageSegue +然后将这些静态常量放到 struct 中. ShowImageSegue 171 00:08:47,227 --> 00:08:51,296 = "Show Image". So that this string, and basically any += "Show Image". 就是这样. 在 172 00:08:51,298 --> 00:08:55,400 string that I put anywhere in my story board, like in these, +storyboard 中的其他 string 也都和这个类似， 173 00:08:55,402 --> 00:08:58,236 when I inspect these things down here like this string. +比如看到的这个下面这个 string 174 00:08:58,238 --> 00:09:02,440 Okay? That's all collected here into this nice struct. +将这些都添加到 struct 中 175 00:09:02,442 --> 00:09:03,208 Okay? So +到此， 176 00:09:03,210 --> 00:09:05,644 we already know that this is what we do to do constants, +我们已经知道怎样处理这些常量了 177 00:09:05,646 --> 00:09:08,113 okay? I'm just calling this group of constants storyboard. +我暂且把这个集合称为 storyboard 常量集吧 178 00:09:08,115 --> 00:09:10,882 They're my storyboard constants, all right? +这就是我的 storyboard 常量集了 179 00:09:10,884 --> 00:09:14,252 All right, so let's do prepare for segue right here. +然后在这里准备 segue 180 00:09:14,254 --> 00:09:15,820 What do we need to do in prepare for segue? +我们需要在 prepareForsSegue 中做哪些处理？ 181 00:09:15,822 --> 00:09:19,324 Well first of all, we probably want to make sure that this is +首先，我们要确保 segue 是 182 00:09:19,326 --> 00:09:23,194 the show image segue, so I'm going to say if the segue's +show image segue，所以先进行判断 183 00:09:23,196 --> 00:09:28,366 identifier = the storyboard.ShowImageSegue. +segue 的 identifier 是否等于 Storyboard.ShowImageSegue 184 00:09:28,368 --> 00:09:31,469 Okay? Then we know this is what we're preparing for. +这一步是保证我们处理的是正确的 segue 185 00:09:31,471 --> 00:09:34,539 And remember, +记住，在一个复杂的 app 中，可能会有很多不同的 186 00:09:34,541 --> 00:09:37,309 of segues, like we have in emotions actually, with +segue，就像我们有不同的情绪一样，它们有 187 00:09:37,311 --> 00:09:39,911 different identifiers going off. So that's why we almost +不同的标识. 所以我们 188 00:09:39,913 --> 00:09:43,114 always check the identifier first just to make sure +通常使用 identifier 来确保 189 00:09:43,116 --> 00:09:44,583 that we are doing the right thing, and +处理方式是对的 190 00:09:44,585 --> 00:09:48,153 usually we'll try and spell identifier properly. Okay. +当然，还需要正确的拼写 identifier 191 00:09:48,155 --> 00:09:52,157 So now, we know this is the right segue. We need to get +现在，我们知道这里就是想要的 segue 了. 还需要 192 00:09:52,159 --> 00:09:55,293 the MVC that we're segueing to so we can prepare it. +有一个 MVC 结构来准备 segue 193 00:09:55,295 --> 00:09:57,662 So we know that's supposed to be an Image View Controller so +假设需要的是 Image View Controller 194 00:09:57,664 --> 00:10:00,999 I'm going to say if I can let IVC, short for +所以定义一个叫做 ivc 的常量 195 00:10:01,001 --> 00:10:01,900 Image View Controller, +ImageViewController 的简写 196 00:10:01,902 --> 00:10:07,772 equal the segue's destination view controller as +等于 segue 的 destinationViewController 197 00:10:07,774 --> 00:10:11,843 an image view controller. Okay. +转换为 ImageViewController 198 00:10:11,845 --> 00:10:15,513 So if I, I don't even need the parentheses there, sorry. So +这里不需要大括号，不好意思 199 00:10:15,515 --> 00:10:19,217 if I can get that destination view controller as an image +如果能正确将 destinationViewController 转为 200 00:10:19,219 --> 00:10:24,122 view controller then now I'm ready to prepare this thing. +ImageViewController，那么就可以开始做一些准备了 201 00:10:24,124 --> 00:10:26,024 So, how do I need to prepare it? Well, +怎样去准备呢？ 202 00:10:26,026 --> 00:10:29,828 it depends on which button Is doing this show image, okay. +这要取决于哪个按钮触发显示图片事件 203 00:10:29,830 --> 00:10:32,564 So, I'm actually gonna look back at the button. Now, +所以，回头看看这些按钮 204 00:10:32,566 --> 00:10:34,966 -here's the button. Remember it prepares for seque. +here's the button. Remember it prepares for segue. +这个参数就是按钮，并且是谁触发的 segue， 205 00:10:34,968 --> 00:10:38,970 The sender is the button or the line in a table or +那这个 sender 就是谁，可能是按钮或者 table 的某一行 206 00:10:38,972 --> 00:10:40,772 something like that that caused it to happen. +或者其他触发事件的对象 207 00:10:40,774 --> 00:10:43,108 So, I need to convert this into a button. So +所以，我需要将它强转为 button 208 00:10:43,110 --> 00:10:46,411 I could actually do this like this. I could say, if I can +我可以这样做，如果 sender 209 00:10:46,413 --> 00:10:52,017 let the sending button equal the sender as a UI button, +是 UIButton，并解包给 sendingButton 不为空 210 00:10:52,019 --> 00:10:55,887 then I can go forward here and say let's let the image name, +那么就可以定义一个 imageName 211 00:10:55,889 --> 00:10:57,822 that's the name of the image we wanna show, +代表我们想要显示的图片名称 212 00:10:57,824 --> 00:11:02,827 equal the sending button's current title. Oops, +并将 sendingButton 的当前图片，哦，不 213 00:11:02,829 --> 00:11:05,363 not current image, current title. All right, so +当前标题. 214 00:11:05,365 --> 00:11:06,531 this'll be one way to do this, +这是一种处理方式 215 00:11:06,533 --> 00:11:11,603 okay, but kind of a cool way here is, this is this, right? +但是还有一种更好的方法，看这个和这个 216 00:11:11,605 --> 00:11:14,205 So what if I took this, cut and +如果我将这个 217 00:11:14,207 --> 00:11:17,375 put it in here like that. Okay, so +剪切到这里 218 00:11:17,377 --> 00:11:21,479 I don't need this except for this is If, let. So, if I put +那就不再需要这个 if let 了，但如果 219 00:11:21,481 --> 00:11:24,616 this in here, this is going to be an optional. I can't send +将它放到这里，那这就会是个可选值，不能从可选值 220 00:11:24,618 --> 00:11:28,053 current title to an optional. So, how can I deal with that? +中直接访问 currentTitle 属性. 该怎么办呢？ 221 00:11:28,055 --> 00:11:33,124 Let's use optional chaining. Okay? So it's perfectly legal +让我们试试可选链. 在表达式返回可选值的时候 222 00:11:33,126 --> 00:11:36,494 to use the optional chaining stuff on the end of some, +使用可选链来操作 223 00:11:36,496 --> 00:11:39,898 some other expression that returns a possible optional. +是完全合法的 224 00:11:39,900 --> 00:11:42,400 And remember, if this is nil right here, +如果这里是 nil 225 00:11:42,402 --> 00:11:43,868 then this whole thing's just gonna be ignored. +那么之后的都会被忽略 226 00:11:43,870 --> 00:11:46,571 That's what the question mark means, it means if it's nil, +这个问号就是表示可能为 nil 227 00:11:46,573 --> 00:11:48,206 nil then just return nil and ignore it. +遇到 nil 会返回 nil，然后忽略掉 228 00:11:48,208 --> 00:11:52,677 That means imageName is gonna be returned to nil. Okay. +也就是说 imageName 可能为 nil 229 00:11:52,679 --> 00:11:55,947 See how I did that? This cleans up our code a little +接下来做什么呢？先把代码 230 00:11:55,949 --> 00:11:58,616 bit, to do that. Less if then, if thens and +整理一下. 减少分支语句 231 00:11:58,618 --> 00:12:02,554 all that, business around there. Okay? Now I'm going +接下来，要根据 232 00:12:02,556 --> 00:12:06,291 to go get the image that goes with this button's title. +按钮的 title 来获取图片 233 00:12:06,293 --> 00:12:07,659 Now let me show you how we're gonna do that. +让我来演示一下 234 00:12:07,661 --> 00:12:10,462 This DemoURL class, remember the one that had that little +这个 DemoURL 类，有一个 Stanford 的 URL 235 00:12:10,464 --> 00:12:14,165 Stanford URL in there? Well it also had these NASA URLs, +还有 NASA 的 URL 236 00:12:14,167 --> 00:12:16,568 one for Cassini, one for Earth, and one for Saturn. +里面包含 Cassini，Earth 和 Saturn 237 00:12:16,570 --> 00:12:17,802 Those are the three buttons we have. And +对应着我们的三个按钮 238 00:12:17,804 --> 00:12:20,939 I have a little function right here that just gets the name +这还有个简单的方法，接收图片名称 239 00:12:20,941 --> 00:12:24,676 of the image and looks it up in that dictionary right here, +然后在字典中查找 240 00:12:24,678 --> 00:12:27,979 okay, and returns it. So this a little function called +并返回，所以这个方法叫 241 00:12:27,981 --> 00:12:30,815 NASA Image Named. So let's use this NASA Image Named. +NASAImageNamed. 来调用下这个方法 242 00:12:30,817 --> 00:12:35,520 I'm just gonna say right here that the IVC's image URL +在这里写 ivc 的 imageURL 243 00:12:35,522 --> 00:12:41,326 equals the NASAImageNamed this imageName. Okay? +等于 NASAImageNamed 的这个 imageNames 244 00:12:41,328 --> 00:12:46,731 This thing I got right here. >> [COUGH] +就这样 245 00:12:46,733 --> 00:12:47,398 >> All right. +能跟上吗 246 00:12:47,400 --> 00:12:50,502 And then, oops, sorry, this has gotta be DemoURL., +接下来，哦，不好意思，要加上 DemoURL. 247 00:12:50,504 --> 00:12:52,670 because it's over here in this DemoURL. +因为这个方法在 DemoURL 中 248 00:12:52,672 --> 00:12:55,306 Notice this is a static function, right? +注意这是个静态方法 249 00:12:55,308 --> 00:12:56,341 NASAImageNamed is static function. +NASAImageNamed 是个静态方法 250 00:12:56,343 --> 00:12:59,611 So, we send it to the class DemoURL, that's why I had to +所以应该用 DemoURL 类来调用，所以 251 00:12:59,613 --> 00:13:05,116 put DemoURL here. Okay, just kind of a utility function for +应该加上 DemoURL. 这只是 DemoURL 中 252 00:13:05,118 --> 00:13:08,820 that little DemoURL class. And while we're at it, +的一个工具方法而已. 接下来， 253 00:13:08,822 --> 00:13:12,323 you know what, let's set the title of that MVC to be that +将 MVC 结构的 title 设置为 254 00:13:12,325 --> 00:13:15,527 image name as well. So that way we'll Earth or Cassini or +图片名字吧. 这样 MVC 的 title 会是 Earth 或 Cassini 255 00:13:15,529 --> 00:13:21,766 whatever as the title of that MVC. Okay so this make sense? +或者其他的名字. 这就是这段代码的作用 256 00:13:22,068 --> 00:13:25,203 Everybody okay now? Let's go ahead and run this and +都能跟上吗？运行程序 257 00:13:25,205 --> 00:13:30,141 see if this is working. Here we go. +看看效果 258 00:13:33,380 --> 00:13:37,081 Okay, there we go. So here's Cassini right here, and +运行起来了，这是 Cassini， 259 00:13:37,083 --> 00:13:41,686 if I click Earth, okay, whoa. So it worked. I clicked Earth +如果我点击 Earth，有点击效果. 点击了 Earth 260 00:13:41,688 --> 00:13:44,923 but nothing's happening in my app. Wait, no there, +但是 app 却没做出响应. 等下，不对啊 261 00:13:44,925 --> 00:13:47,358 it's showing Stanford. Why is is showing Stanford here? +这展示的是斯坦福，为什么会这样？ 262 00:13:47,360 --> 00:13:50,361 Well, that's because our nice reusable image view controller +那是因为我们重用的 ImageViewController 263 00:13:50,363 --> 00:13:54,732 we have over here, it's view did load smashes Stanford on +的 viewDidLoad 方法中，将斯坦福盖在了 264 00:13:54,734 --> 00:13:57,435 top of everything. So, that we only put that in there as +所有视图的顶部. 这只是之前的 demo 265 00:13:57,437 --> 00:14:01,105 a demo. Right, so I'm taking that out, sorry about that. +把它提出来，不好意思 266 00:14:01,107 --> 00:14:02,707 Makes everyone see what happened there. So +现在来看看都发生了什么 267 00:14:02,709 --> 00:14:05,143 now let's go back here. It won't be slamming a Stanford +重新运行一次，这下我们的重用 ImageViewController 268 00:14:05,145 --> 00:14:08,880 in there in our reusable image view controller. Okay? So +应该不会被斯坦福盖住了 269 00:14:08,882 --> 00:14:11,182 now we'll go back to Cassini. We'll pick Earth this time. +回到 Cassini 界面，选择 Earth 270 00:14:11,184 --> 00:14:15,119 diff --git a/subtitles/9. Table View.srt b/subtitles/9. Table View.srt old mode 100644 new mode 100755 From 54e486b16639b0fad933f2517f14cfdcb26251ce Mon Sep 17 00:00:00 2001 From: saitjr Date: Wed, 17 Aug 2016 09:54:34 +0800 Subject: [PATCH 05/23] 8. 260-360 --- .../8. Multithreading and Text Field.srt | 110 +++++++++++++++++- 1 file changed, 109 insertions(+), 1 deletion(-) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index 3061ba8..b4162c3 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -1345,435 +1345,543 @@ now we'll go back to Cassini. We'll pick Earth this time. 270 00:14:11,184 --> 00:14:15,119 Again it seems like it's kinda stuck. I can't click on any of +又卡住了. 所有按钮都 271 00:14:15,121 --> 00:14:17,989 these buttons. I can't, actually I can't do anything. +无法点击. 点不了，什么都做不了 272 00:14:17,991 --> 00:14:21,025 There it is. Okay. So that must have been a really big +进来了，真是一张大图 273 00:14:21,027 --> 00:14:24,462 image. It took a very long time to load and here it is. +需要这么长的时间加载，终于显示出来了 274 00:14:24,464 --> 00:14:27,131 It doesn't really look like Earth, but +看起来不怎么像是地球， 275 00:14:27,133 --> 00:14:29,634 pictures of people on Earth, hm. That's interesting., +倒像是地球上的人，有意思. 276 00:14:29,636 --> 00:14:32,503 Let's try one of these others. Let's try Cassini here. Okay, +再试试别的，试试 Cassini 277 00:14:32,505 --> 00:14:35,106 what happening? This is, basically, just blank. +怎么回事，怎么只有一个白板 278 00:14:35,108 --> 00:14:39,310 What's going on here? How about Saturn? Again, +怎么回事？再试试 Saturn 呢？又来了 279 00:14:39,312 --> 00:14:41,312 taking a really long time, you can see why we're gonna talk +又要等很久，这就是为什么之后我们要讲 280 00:14:41,314 --> 00:14:45,583 about multi-threading a little later. Okay, and here it is, +多线程. 好，进来了 281 00:14:45,585 --> 00:14:47,385 okay that's not good either. All right, so +看起来也不怎么像. 好吧， 282 00:14:47,387 --> 00:14:50,722 we gotta start here. We know the Cassini's not working. +刚才发现 Cassini 没能正常显示 283 00:14:50,724 --> 00:14:53,258 It comes up blank. So why might Cassini not be working. +看到一片空白，为什么会这样 284 00:14:53,260 --> 00:14:56,027 Let's go back here and check for example to make sure that +回到这里，检查下 segue 有没有什么问题 285 00:14:56,029 --> 00:14:59,030 our segue is good. Okay, the Earth's segue. Here's +这是 Earth 的 segue，这是 286 00:14:59,032 --> 00:15:02,667 the Cassini segue. Let';s go look at its identifier. +Cassini 的 segue. 来检查下它的 identifier 287 00:15:02,669 --> 00:15:06,905 Look at that. This Cassini identifier, no identifier. +看到没，Cassini 的 identifier 是空的 288 00:15:06,907 --> 00:15:08,940 So let's put show image in here. Okay? +设置为 Show Image 289 00:15:08,942 --> 00:15:11,743 So when you have a segue and it doesn't seem to be working, +所以，如果你有一个segue，但是没能正常响应 290 00:15:11,745 --> 00:15:12,877 like it segues to the new MVC but +比如想推出一个新的 MVC，但是 291 00:15:12,879 --> 00:15:15,346 the prepared doesn't happen, often you want to go back and +prepare 中的代码没有运行，通常需要回头 292 00:15:15,348 --> 00:15:17,715 look at your identifier, make sure it's set properly or +检查下 identifier，确保它正确的 293 00:15:17,717 --> 00:15:21,419 set in there. Okay, so now, if we go back here. +赋了值. 现在重新运行 294 00:15:25,458 --> 00:15:27,558 All right, we have Cassini here. Let's click on it. +找到 Cassini 并点击 295 00:15:27,560 --> 00:15:30,728 Again, it's loading. That one must be a smaller image. +再次等待加载，这图片应该不大 296 00:15:30,730 --> 00:15:32,797 It loaded pretty quick. And here it is. +加载起来很快，显示出来了 297 00:15:32,799 --> 00:15:36,234 It looks like it's just a bunch of outer space. Okay, so +看起来就只是外太空而已 298 00:15:36,236 --> 00:15:36,935 we've got a problem here, +现在有一个问题 299 00:15:36,937 --> 00:15:39,637 which is that these images that I loaded are huge. That's +当我们加载一些大图的时候 300 00:15:39,639 --> 00:15:44,008 created two problems for us. One, our app get's blocked. +有两个问题摆在了面前. 一个是 app 被卡死了 301 00:15:44,010 --> 00:15:46,878 See I can't click on anything else. I can't even rotate or +任何东西都没办法点击. 连旋转都不行 302 00:15:46,880 --> 00:15:49,547 anything here. My app is just completely stuck. +app 完完全全卡住 303 00:15:49,549 --> 00:15:51,916 You never want your app in that circumstance. +你肯定不想你的 app 出现这样的情况 304 00:15:51,918 --> 00:15:54,652 Never should your app be stuck like that. Users will just, +你们的 app 绝不能出现这样的情况. 用户发现， 305 00:15:54,654 --> 00:15:56,988 basically, double click on the home button and +就会双击 home 键 306 00:15:56,990 --> 00:15:58,456 kill your app and never run it again. +然后杀死进程，再也不会用了 307 00:15:58,458 --> 00:16:00,925 They'll think your app is totally hosed. And it is, +他们会觉得你的 app 太烂了，这就是 308 00:16:00,927 --> 00:16:04,228 if it behaves that way, okay, so we really need to fix that. +界面卡死的后果，所以我们需要修复下 309 00:16:04,230 --> 00:16:06,197 The other thing is, this image is so +另外一个问题就是，图片太大 310 00:16:06,199 --> 00:16:09,500 huge that we can't really see it. So we'd like to be able to +无法直观的展示. 所以我们要添加 311 00:16:09,502 --> 00:16:11,936 zoom in on it, right. So let's go ahead and +缩放功能. 先来处理 312 00:16:11,938 --> 00:16:17,508 do the zooming, okay? How do we do the zooming in our, +缩放吧. 怎么在 ImageViewController 中 313 00:16:18,178 --> 00:16:19,844 back here in our image view controller, right? +做缩放呢？ 314 00:16:19,846 --> 00:16:22,146 So our image view controller has this scroll view, +ImageViewController 有一个 scrollView 315 00:16:22,148 --> 00:16:24,983 right? That we dragged into the storyboard. It's got this +我们拖到 storyboard 中的. 并将 imageView 添加 316 00:16:24,985 --> 00:16:28,453 image view as the subview of the scroll view. Okay, and +到了 scrollView 上 317 00:16:28,455 --> 00:16:31,556 we set our content size, so it's working nicely. And +我们还设置了 contentSize，看起来非常棒 318 00:16:31,558 --> 00:16:32,857 we know from the slides last time that +从之前的幻灯片我们知道了 319 00:16:32,859 --> 00:16:37,495 to make zooming work. Okay, we need to set some other things. +缩放的原理. 那这里还需要处理一些东西 320 00:16:37,497 --> 00:16:39,364 What are some of the things we need to do? Well, +需要怎么做呢？ 321 00:16:39,366 --> 00:16:42,600 the most important thing is we need to set ourselves +最重要的一点，就是要将我们自己设置为 322 00:16:42,602 --> 00:16:44,135 as the scrollView's delegate. Okay, so +scrollView 的 delegate. 323 00:16:44,137 --> 00:16:48,373 this is the first time you're seeing delegation demoed here. +这是我们在 demo 中第一次用到 delegate 324 00:16:48,375 --> 00:16:48,773 And the way we do that, +我的做法是 325 00:16:48,775 --> 00:16:52,844 I'd probably do it here in my scrollView didSet here, right? +在 scrollView 的 didSet 方法中来设置 326 00:16:52,846 --> 00:16:55,680 The didSet for my scrollView. Probably just say that Mr. +这就是 scrollView 的 didSet 方法. 这样说， 327 00:16:55,682 --> 00:17:00,084 scrollView, please set your delegate to be self. In other +亲爱的 scrollView，让我成为你的代理吧！换句话说， 328 00:17:00,086 --> 00:17:04,856 words, send me any questions you have about how to operate. +就是把你的问题抛给我来处理吧 329 00:17:04,858 --> 00:17:07,125 Now when I put that in there I have a error, +照我这样设置出现了一个错误 330 00:17:07,127 --> 00:17:11,796 anyone guess what this error is? Okay, +有谁知道这是什么错误吗？ 331 00:17:11,798 --> 00:17:14,699 it's going to say that these types, this and +错误是说，他们的类型，这个和 332 00:17:14,701 --> 00:17:18,870 this do not match. Okay, and why is that? The type of this +这个不匹配. 为什么呢？这个的类型是... 333 00:17:18,872 --> 00:17:22,006 is, well the type of this, not showing, but the type of this +好吧，看不到，但是这个的类型是 334 00:17:22,008 --> 00:17:27,211 is UI scrollView delegate. Which is a protocol, okay. +UIScrollViewDelegate. 是个协议 335 00:17:27,213 --> 00:17:31,883 The type of this is UI or image view controller. +这个类型是 UI...哦，是ImageViewController 336 00:17:31,885 --> 00:17:34,652 That's its type. Those don't match. Okay, so +这就是它们的类型，并不匹配. 难怪 337 00:17:34,654 --> 00:17:38,523 that's why this says cannot assign value of type image +报错说不能将 ImageViewController 338 00:17:38,525 --> 00:17:42,260 view controller to UI scroll view delegate, optional. +赋值给可选的 UIScrollViewDelegate 339 00:17:42,262 --> 00:17:46,230 Okay, so we need to say that this image view controller is +所以，我们要先让 ImageViewController 遵循 340 00:17:46,232 --> 00:17:51,736 a UI scroll view delegate. And we do that by just putting +UIScrollViewDelegate. 需要做的是，将 UIScrollViewDelegate 声明在 341 00:17:51,738 --> 00:17:54,672 that right after our super class there, a little comma, +父类的右边，逗号分隔 342 00:17:54,674 --> 00:17:57,642 UIScrollViewDelegate, and that says we are scroll view +这表明我们就是 scrollView 343 00:17:57,644 --> 00:18:00,178 delegate, and all of a sudden this works. +的代理，这样就没问题了 344 00:18:00,180 --> 00:18:03,047 Now UIScrollViewDelegate has no methods or +UIScrollViewDelegate 没有方法或 345 00:18:03,049 --> 00:18:05,950 vars in there that are not optional. In other words +变量是不可选的，换句话说， 346 00:18:05,952 --> 00:18:08,853 they're all optional, so we've successfully implemented so +它们都是可选的，所以，遵循以后 347 00:18:08,855 --> 00:18:10,688 the compiler's not complaining. Okay, +编译器并没有报错 348 00:18:10,690 --> 00:18:14,725 cuz none of them are required. But, we still wanna implement +因为没有必须实现的方法. 不过我们还是需要实现 349 00:18:14,727 --> 00:18:17,995 one, that zooming one, which is called +其中一个方法，缩放的那个，叫做 350 00:18:17,997 --> 00:18:19,363 viewForZoomingInScrollView. Now, one +viewForZoomingInScrollView. 在你 351 00:18:19,365 --> 00:18:21,632 thing that's cool is once you say that you're a ScrollView +成为 ScrollView 的代理之后， 352 00:18:21,634 --> 00:18:24,735 delegate, look what happens when I start typing view +在最新的 Xcode 键入字母时 353 00:18:24,737 --> 00:18:26,971 in Xcode. It knows I'm a ScrollView delegate, so +它就知道你已经是 ScrollView 的代理了，所以 354 00:18:26,973 --> 00:18:30,308 the very first thing it offers me is viewForScroll, +提供的首个联想方法就是 viewForScroll 355 00:18:30,310 --> 00:18:33,177 ScrollingInScrollView. For +ZoomingInScrollView（白胡子口误了） 356 00:18:33,179 --> 00:18:36,981 -zooming in scrollView. Right? So that's kind of cool. And +zooming in scrollView.、 Right? So that's kind of cool. And +用做 scrollView 的缩放. 这真的非常棒 357 00:18:36,983 --> 00:18:40,017 what view, which of the scrollView subviews do we want +那个视图？我们想让 scrollView 的哪个子视图 358 00:18:40,019 --> 00:18:44,622 to zoom in on? Well, of course, the image view. This +做缩放？当然是 imageView. 这是 359 00:18:44,624 --> 00:18:48,159 is our image view right here that we store our image in. +我们的 imageView，里面存储了相应图片 360 00:18:48,161 --> 00:18:49,494 That's of course the thing we want +很明显我们是想 361 00:18:49,496 --> 00:18:54,599 to have its transform modified when we pinch in there. Okay? +在手指捏合的时候，对图片做对应的缩放 362 00:18:54,601 --> 00:18:56,400 Now you might think okay, that's good. +你可能会想，那已经完成了， 363 00:18:56,402 --> 00:19:00,505 Got it all ready to go. Let's go start zooming, and +可以运行了. 让我来看看缩放效果吧 364 00:19:00,507 --> 00:19:03,341 we'll go over here. Let's get Cassini, kinda small. +到这个界面，打开 Cassini，一张小图 365 00:19:03,343 --> 00:19:06,277 Let's start zooming. Now how do I zoom? It's with Pinch, so +试试缩放. 怎么进行缩放呢？需要捏合手势，所以 366 00:19:06,279 --> 00:19:08,913 I'm gonna hold down the Option key right here and +按住 Option 键，然后 367 00:19:08,915 --> 00:19:11,048 start pinching. And it's not working. +进行捏合. 但并没有效果 368 00:19:11,050 --> 00:19:14,085 It's not doing anything. Okay, I can still scroll but +完全没有效果. 依然可以滚动，但是 369 00:19:14,087 --> 00:19:18,990 I can't zoom in. Anyone know why? Say +不能缩放. 有人知道为什么吗？大点声. 370 00:19:18,992 --> 00:19:25,396 it louder. I think I might have heard it back there. +我刚才好像听到那有人回答. 371 00:19:25,398 --> 00:19:28,065 Yeah, this right now, our scrollView by default, +是的，没错，现在 scrollView 的默认值是 372 00:19:28,067 --> 00:19:31,836 it's maximum zoom and its minimum zoom is 1.0. +放大倍数和缩小倍数都是 1.0 373 00:19:31,838 --> 00:19:33,738 So it is zooming to the maximum, +所以我们放大 374 00:19:33,740 --> 00:19:36,974 minimum extent we allow which is none, 1.0. So +和缩小的效果根本看不出来，都是 1.0，所以 375 00:19:36,976 --> 00:19:41,779 we need to set the maximum and minimum scrolling factor or +我们需要给 scrollView 的范围因子，或叫做 376 00:19:41,781 --> 00:19:45,583 zooming factor on this scrollView. So let's do that. +缩放因子赋值. 回到代码. 377 00:19:45,585 --> 00:19:48,386 Let's do that also right here when we're setting our + 378 00:19:48,388 --> 00:19:50,254 scrollView from our storyboard. So From 8fb2258e6c9ff6d8859df7b8229fea3c9c175c5b Mon Sep 17 00:00:00 2001 From: Xinyu Zhao Date: Mon, 22 Aug 2016 23:15:35 +0800 Subject: [PATCH 06/23] add download link --- download.md | 49 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 download.md diff --git a/download.md b/download.md new file mode 100644 index 0000000..e516c5c --- /dev/null +++ b/download.md @@ -0,0 +1,49 @@ +# Video +[lecture 1](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic1/v4/64/b0/84/64b084ce-11d0-a3ff-e901-bcb0b38340b9/318-3290009375018043679-01_iTunes_CS193P_03_28_16_1080_720p_1500cc.m4v) +[lecture 2](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/45/74/46/45744676-931d-e1d4-1787-952713e66c45/320-8373286204145257290-02_CS193P_3_30_16_720p1500cc.mp4) +[lecture 3](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/a8/92/8e/a8928e55-ff74-cd37-6c9d-a91d1dda2b71/309-7506772204647137370-03_CS193P_4_04_16_1080p_3mb_cc2.m4v) +[lecture 4](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/70/86/bf/7086bfd5-f133-6686-a319-7ba7947bae16/305-7247414449295650666-04_CS193P_4_06_16_1080p_3mb_cc.m4v) +[lecture 5](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/36/91/d6/3691d659-ec3b-d34f-b8ec-a92e1183095f/328-1962441713930624806-05_CS193P_4_11_16_1080p_3mb_cc.m4v) +[lecture 6](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/ab/b2/70/abb270a8-6473-7658-72b6-f614a3bd5489/333-2664853460560613531-06_CS193P_4_13_16_rev_1080p_3mb.m4v) +[lecture 7](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/81/b0/1f/81b01f26-ccd9-9df7-df6f-c5d34aea47aa/302-7208808734861639493-07_CS193__4_18_16_1080p_3mb_cc.m4v) +[lecture 8](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/99/1e/e0/991ee064-fcd4-267f-4595-361d14bc09d0/336-4841244943511706201-08_CS193_4_20_16_1080p_3mb_cc.m4v) +[lecture 9](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/b3/4f/d0/b34fd003-ee43-43dc-4b21-6c355688fb3c/311-4524248345011539875-09_CS193_4_25_16_1_1080p_3mb.m4v) +[lecture 10](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/df/93/44/df9344e9-03cf-fcfe-e550-3548d53c190d/326-7677824725330965182-10_CS193_4_27_16_1_1080p_3mb.m4v) +[lecture 11](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/d8/08/29/d80829e3-fced-1630-5942-5306cc663461/322-952121251318135044-11_CS193_5_02_16_1080p_3mb.m4v) +[lecture 12](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/64/6c/40/646c4016-9bd4-d378-a880-2ac977f38093/330-2525015638168359918-12_CS193_5_04_16_rev2_1080p_3mb.m4v) +[lecture 13](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/14/a3/b6/14a3b675-ba6c-7594-fcb7-fc0b4e82a0b7/310-1407346536923462131-13_CS193_5_09_16_1080p_3mb.m4v) +[lecture 14](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/f1/ca/44/f1ca444b-4578-8114-7297-555f4cdc9b57/326-7999025039413500594-14_CS193_5_11_16_1080p_3mb.m4v) +[lecture 15](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/80/eb/65/80eb6594-3604-9eac-1a93-187de9e32c1e/337-4900765140487554688-15_CS193_5_16_16_1080p_3mb.m4v) +[lecture 16](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/2b/9a/58/2b9a58e0-7761-b64f-45a2-2582d7f93644/324-5681395727728634007-16_CS193_5_18_16_1080p_3mb.m4v) +[lecture 17](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/bb/39/61/bb3961d5-73a0-42ec-1e71-0336508e9dfa/311-3400152801833314139-17_CS193_5_23_16_1080p_3mb.m4v) +[lecture 18](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/c8/db/e9/c8dbe99d-6f8e-28f5-47f4-ffe0c873d021/335-740161242915993166-18_CS193_5_25_16_1080p_3mb.m4v) + +# Slides +[lecture 1 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic1/v4/f4/05/ff/f405ffb5-50b0-95c6-fd17-a6c262311a2d/321-5596613686960899183-CS193P_S16_Lecture_1_Slides.pdf) +[lecture 2 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/ef/31/cc/ef31cc34-7cd0-e3c4-425c-e7f75a262f00/321-3432256539360740647-CS193P_S16_Lecture_2_Slides.pdf) +[lecture 3 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/e6/a1/7e/e6a17ee2-b99f-3221-addd-da39d12d8802/321-6470380314597358395-CS193P_S16_Lecture_3_Slides.pdf) +[lecture 4 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/fb/b9/58/fbb95870-c6be-79e2-77c5-c6474b8a40bf/307-5050413922657858617-CS193P_S16_Lecture_4_Slides.pdf) +[lecture 5 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/7d/de/00/7dde003d-b32b-93fc-9786-0ec16c29ffb5/334-741241953225611839-CS193P_S16_Lecture_5_Slides.pdf) +[lecture 6 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/ae/3e/6e/ae3e6ece-fead-e585-2035-756ccd82bfd0/308-1536759857490550427-CS193P_S16_Lecture_6_Slides.pdf) +[lecture 7 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/47/02/9e/47029e12-1843-f40c-095c-ce3781137ed0/308-1708618185040143775-CS193P_S16_Lecture_7_Slides.pdf) +[lecture 8 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/57/48/6c/57486c13-678e-7892-9cb4-9dbd58ab6fae/328-2295701575035385283-CS193P_S16_Lecture_8_Slides.pdf) +[lecture 9 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/31/fb/33/31fb33c5-65ff-8e07-9c8a-2c49dd75f734/319-404525925375936666-CS193P_S16_Lecture_9_Slides.pdf) +[lecture 10 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/7c/36/24/7c36249c-605a-8fc7-5c6c-a49abe0c8d37/317-3926700305190050506-CS193P_S16_Lecture_10_Slides.pdf) +[lecture 11 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/52/74/73/52747331-a857-1914-9ebb-dc4a6dde68e7/319-3727135049627801646-CS193P_S16_Lecture_11_Slides.pdf) +[lecture 12 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/f2/9c/61/f29c6128-8f92-5c81-b1ce-6d0d62d29f0c/318-7132989426423920990-CS193P_S16_Lecture_12_Slides.pdf) +[lecture 13 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/c5/37/96/c537967b-6e29-f272-b57a-88e0ce60d531/306-350276286767890645-CS193P_S16_Lecture_13_Slides.pdf) +[lecture 14 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/9b/5e/59/9b5e5936-5126-85d4-6b18-4a13d9e7afc5/335-2050748076731576057-CS193P_S16_Lecture_14_Slides.pdf) +[lecture 15 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/55/28/db/5528dbac-7421-90ea-0d18-61d8b085e7e1/304-2868878214971040553-CS193P_S16_Lecture_15_Slides.pdf) +[lecture 16 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/42/13/f9/4213f984-9a28-80ac-8db8-b242dd377c4c/335-760378487450689313-CS193P_S16_Lecture_16_Slides.pdf) +[lecture 17 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/d8/aa/24/d8aa2482-9c87-d22a-ecec-c5bff601bc0e/322-3967892605293848768-CS193P_S16_Lecture_17_Slides.pdf) +[lecture 18 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/d9/38/2c/d9382c15-0379-0000-3cbe-233ac1f92023/328-8624592354314154483-CS193P_S16_Lecture_18_Slides.pdf) +[project 1](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/8b/a7/8c/8ba78c73-a911-b9d9-7406-7b6c35b1a635/330-4665516795304515844-CS193P_S16_Programming_Project_1.pdf) +[project 2](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/62/62/f2/6262f2b4-721c-d325-3c23-ced31802068d/303-6526141645397285536-Programming_2.pdf) +[project 3](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/90/64/be/9064beaa-cc04-ad7f-30e4-a9330e21caba/320-5665175142130618734-CS193P_S16_Programming_Project_3.pdf) +[project 4](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/0b/d2/ad/0bd2ad88-4abf-29a5-b406-cefeb3637c55/315-4965520355348488665-CS193P_S16_Programming_Project_4.pdf) +[project 5](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/e8/ba/cc/e8bacc96-9c52-8652-5613-950db7b65e5e/328-5947046615294240890-CS193P_S16_Programming_Project_5.pdf) +[project 6](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/46/05/9a/46059aff-bffb-1dcf-00ef-0d22bad80b47/322-6708752098278348100-CS193P_S16_Programming_Project_6.pdf) +[reading 1](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/df/8f/72/df8f7285-414d-f3f3-318a-6bb7246252b8/329-6584533342020921682-Reading_1.pdf) +[reading 2](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/32/fc/8b/32fc8b6a-bc29-8977-9035-1fc2b1b427d3/323-869352964012275742-Reading_2.pdf) +[reading 3](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/4a/d9/8f/4ad98f9f-18ba-7d7e-8a3e-99e8bebd2e82/313-6521184191452265856-Reading_3_2.pdf) + From 596289df1645c1864f43240229b753db3303ebd4 Mon Sep 17 00:00:00 2001 From: Xinyu Zhao Date: Mon, 22 Aug 2016 23:17:24 +0800 Subject: [PATCH 07/23] add empty lines --- download.md | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) diff --git a/download.md b/download.md index e516c5c..ea91963 100644 --- a/download.md +++ b/download.md @@ -1,49 +1,92 @@ # Video [lecture 1](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic1/v4/64/b0/84/64b084ce-11d0-a3ff-e901-bcb0b38340b9/318-3290009375018043679-01_iTunes_CS193P_03_28_16_1080_720p_1500cc.m4v) + [lecture 2](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/45/74/46/45744676-931d-e1d4-1787-952713e66c45/320-8373286204145257290-02_CS193P_3_30_16_720p1500cc.mp4) + [lecture 3](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/a8/92/8e/a8928e55-ff74-cd37-6c9d-a91d1dda2b71/309-7506772204647137370-03_CS193P_4_04_16_1080p_3mb_cc2.m4v) + [lecture 4](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/70/86/bf/7086bfd5-f133-6686-a319-7ba7947bae16/305-7247414449295650666-04_CS193P_4_06_16_1080p_3mb_cc.m4v) + [lecture 5](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/36/91/d6/3691d659-ec3b-d34f-b8ec-a92e1183095f/328-1962441713930624806-05_CS193P_4_11_16_1080p_3mb_cc.m4v) + [lecture 6](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/ab/b2/70/abb270a8-6473-7658-72b6-f614a3bd5489/333-2664853460560613531-06_CS193P_4_13_16_rev_1080p_3mb.m4v) + [lecture 7](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/81/b0/1f/81b01f26-ccd9-9df7-df6f-c5d34aea47aa/302-7208808734861639493-07_CS193__4_18_16_1080p_3mb_cc.m4v) + [lecture 8](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/99/1e/e0/991ee064-fcd4-267f-4595-361d14bc09d0/336-4841244943511706201-08_CS193_4_20_16_1080p_3mb_cc.m4v) + [lecture 9](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/b3/4f/d0/b34fd003-ee43-43dc-4b21-6c355688fb3c/311-4524248345011539875-09_CS193_4_25_16_1_1080p_3mb.m4v) + [lecture 10](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/df/93/44/df9344e9-03cf-fcfe-e550-3548d53c190d/326-7677824725330965182-10_CS193_4_27_16_1_1080p_3mb.m4v) + [lecture 11](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/d8/08/29/d80829e3-fced-1630-5942-5306cc663461/322-952121251318135044-11_CS193_5_02_16_1080p_3mb.m4v) + [lecture 12](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/64/6c/40/646c4016-9bd4-d378-a880-2ac977f38093/330-2525015638168359918-12_CS193_5_04_16_rev2_1080p_3mb.m4v) + [lecture 13](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/14/a3/b6/14a3b675-ba6c-7594-fcb7-fc0b4e82a0b7/310-1407346536923462131-13_CS193_5_09_16_1080p_3mb.m4v) + [lecture 14](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/f1/ca/44/f1ca444b-4578-8114-7297-555f4cdc9b57/326-7999025039413500594-14_CS193_5_11_16_1080p_3mb.m4v) + [lecture 15](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/80/eb/65/80eb6594-3604-9eac-1a93-187de9e32c1e/337-4900765140487554688-15_CS193_5_16_16_1080p_3mb.m4v) + [lecture 16](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/2b/9a/58/2b9a58e0-7761-b64f-45a2-2582d7f93644/324-5681395727728634007-16_CS193_5_18_16_1080p_3mb.m4v) + [lecture 17](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/bb/39/61/bb3961d5-73a0-42ec-1e71-0336508e9dfa/311-3400152801833314139-17_CS193_5_23_16_1080p_3mb.m4v) + [lecture 18](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/c8/db/e9/c8dbe99d-6f8e-28f5-47f4-ffe0c873d021/335-740161242915993166-18_CS193_5_25_16_1080p_3mb.m4v) # Slides [lecture 1 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic1/v4/f4/05/ff/f405ffb5-50b0-95c6-fd17-a6c262311a2d/321-5596613686960899183-CS193P_S16_Lecture_1_Slides.pdf) + [lecture 2 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/ef/31/cc/ef31cc34-7cd0-e3c4-425c-e7f75a262f00/321-3432256539360740647-CS193P_S16_Lecture_2_Slides.pdf) + [lecture 3 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/e6/a1/7e/e6a17ee2-b99f-3221-addd-da39d12d8802/321-6470380314597358395-CS193P_S16_Lecture_3_Slides.pdf) + [lecture 4 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/fb/b9/58/fbb95870-c6be-79e2-77c5-c6474b8a40bf/307-5050413922657858617-CS193P_S16_Lecture_4_Slides.pdf) + [lecture 5 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/7d/de/00/7dde003d-b32b-93fc-9786-0ec16c29ffb5/334-741241953225611839-CS193P_S16_Lecture_5_Slides.pdf) + [lecture 6 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/ae/3e/6e/ae3e6ece-fead-e585-2035-756ccd82bfd0/308-1536759857490550427-CS193P_S16_Lecture_6_Slides.pdf) + [lecture 7 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/47/02/9e/47029e12-1843-f40c-095c-ce3781137ed0/308-1708618185040143775-CS193P_S16_Lecture_7_Slides.pdf) + [lecture 8 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/57/48/6c/57486c13-678e-7892-9cb4-9dbd58ab6fae/328-2295701575035385283-CS193P_S16_Lecture_8_Slides.pdf) + [lecture 9 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/31/fb/33/31fb33c5-65ff-8e07-9c8a-2c49dd75f734/319-404525925375936666-CS193P_S16_Lecture_9_Slides.pdf) + [lecture 10 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/7c/36/24/7c36249c-605a-8fc7-5c6c-a49abe0c8d37/317-3926700305190050506-CS193P_S16_Lecture_10_Slides.pdf) + [lecture 11 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/52/74/73/52747331-a857-1914-9ebb-dc4a6dde68e7/319-3727135049627801646-CS193P_S16_Lecture_11_Slides.pdf) + [lecture 12 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/f2/9c/61/f29c6128-8f92-5c81-b1ce-6d0d62d29f0c/318-7132989426423920990-CS193P_S16_Lecture_12_Slides.pdf) + [lecture 13 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/c5/37/96/c537967b-6e29-f272-b57a-88e0ce60d531/306-350276286767890645-CS193P_S16_Lecture_13_Slides.pdf) + [lecture 14 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/9b/5e/59/9b5e5936-5126-85d4-6b18-4a13d9e7afc5/335-2050748076731576057-CS193P_S16_Lecture_14_Slides.pdf) + [lecture 15 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/55/28/db/5528dbac-7421-90ea-0d18-61d8b085e7e1/304-2868878214971040553-CS193P_S16_Lecture_15_Slides.pdf) + [lecture 16 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/42/13/f9/4213f984-9a28-80ac-8db8-b242dd377c4c/335-760378487450689313-CS193P_S16_Lecture_16_Slides.pdf) + [lecture 17 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/d8/aa/24/d8aa2482-9c87-d22a-ecec-c5bff601bc0e/322-3967892605293848768-CS193P_S16_Lecture_17_Slides.pdf) + [lecture 18 slides](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/d9/38/2c/d9382c15-0379-0000-3cbe-233ac1f92023/328-8624592354314154483-CS193P_S16_Lecture_18_Slides.pdf) + [project 1](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/8b/a7/8c/8ba78c73-a911-b9d9-7406-7b6c35b1a635/330-4665516795304515844-CS193P_S16_Programming_Project_1.pdf) + [project 2](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/62/62/f2/6262f2b4-721c-d325-3c23-ced31802068d/303-6526141645397285536-Programming_2.pdf) + [project 3](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/90/64/be/9064beaa-cc04-ad7f-30e4-a9330e21caba/320-5665175142130618734-CS193P_S16_Programming_Project_3.pdf) + [project 4](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/0b/d2/ad/0bd2ad88-4abf-29a5-b406-cefeb3637c55/315-4965520355348488665-CS193P_S16_Programming_Project_4.pdf) + [project 5](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic18/v4/e8/ba/cc/e8bacc96-9c52-8652-5613-950db7b65e5e/328-5947046615294240890-CS193P_S16_Programming_Project_5.pdf) + [project 6](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic20/v4/46/05/9a/46059aff-bffb-1dcf-00ef-0d22bad80b47/322-6708752098278348100-CS193P_S16_Programming_Project_6.pdf) + [reading 1](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic60/v4/df/8f/72/df8f7285-414d-f3f3-318a-6bb7246252b8/329-6584533342020921682-Reading_1.pdf) + [reading 2](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/32/fc/8b/32fc8b6a-bc29-8977-9035-1fc2b1b427d3/323-869352964012275742-Reading_2.pdf) + [reading 3](https://itunesu-assets.itunes.apple.com/apple-assets-us-std-000001/CobaltPublic30/v4/4a/d9/8f/4ad98f9f-18ba-7d7e-8a3e-99e8bebd2e82/313-6521184191452265856-Reading_3_2.pdf) From b379bed02ceb35abf500d62721e0bbb93043979c Mon Sep 17 00:00:00 2001 From: Xinyu Zhao Date: Mon, 22 Aug 2016 23:19:13 +0800 Subject: [PATCH 08/23] update download links --- README.md | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/README.md b/README.md index a3cf16e..9b489f8 100644 --- a/README.md +++ b/README.md @@ -17,15 +17,15 @@ CS193P 课程地址：[CS193P iPhone Application Development](http://web.stanfor 直接点击[项目 Zip 包](https://github.com/X140Yu/Developing-iOS-9-Apps-with-Swift/archive/master.zip)进行全部已有字幕的下载。 -### 视频及课件第三方网盘下载 +### 视频及课件下载 -[百度网盘](http://pan.baidu.com/s/1kVlf1wr) +[Download](./download.md) ### 联系我们 -如果您想参与项目，请加入 CS193P 工作用 QQ 群：277542197 ，如果你只是想和我们取得联络，请直接在 [Issues](https://github.com/X140Yu/Developing-iOS-9-Apps-with-Swift/issues) 区发言。 +如果您想参与项目，请直接在 [Issues](https://github.com/X140Yu/Developing-iOS-9-Apps-with-Swift/issues) 区发言。 -如果仅仅是想了解翻译的进度，无需加入 QQ 群，关注项目的更新或者到 [Issues](https://github.com/X140Yu/Developing-iOS-9-Apps-with-Swift/issues) 区发言即可。 +如果仅仅是想了解翻译的进度，关注项目的更新或者到 [Issues](https://github.com/X140Yu/Developing-iOS-9-Apps-with-Swift/issues) 区发言即可。 ### 版权说明 From 9fc98f76dfcda603e94c31f70fa74d62c7296ef5 Mon Sep 17 00:00:00 2001 From: Xinyu Zhao Date: Tue, 23 Aug 2016 09:29:16 +0800 Subject: [PATCH 09/23] add subtitle 12 --- subtitles/12. AutoLayout.srt | 3264 ++++++++++++++++++++++++++++++++++ 1 file changed, 3264 insertions(+) create mode 100644 subtitles/12. AutoLayout.srt diff --git a/subtitles/12. AutoLayout.srt b/subtitles/12. AutoLayout.srt new file mode 100644 index 0000000..5c9475f --- /dev/null +++ b/subtitles/12. AutoLayout.srt @@ -0,0 +1,3264 @@ +1 +00:00:00,001 --> 00:00:03,702 +[MUSIC] + +2 +00:00:03,704 --> 00:00:07,973 +Stanford University. >> Welcome to + +3 +00:00:07,975 --> 00:00:12,945 +Lecture 12 of Stanford CS193P, spring of 2016. Today + +4 +00:00:12,947 --> 00:00:15,647 +we have Autolayout, which we've actually been doing + +5 +00:00:15,649 --> 00:00:18,550 +quite a bit of Autolayout, so far, but we're gonna talk + +6 +00:00:18,552 --> 00:00:21,353 +a lot more in detail about the concepts of Autolayout and + +7 +00:00:21,355 --> 00:00:25,491 +things like that. And we're gonna introduce an important + +8 +00:00:25,493 --> 00:00:28,460 +Autolayout feature called Size Classes, okay? + +9 +00:00:28,462 --> 00:00:30,129 +All right, so let's dive in to Autolayout. + +10 +00:00:30,131 --> 00:00:32,798 +So you already know a lot about Autolayout, right? For + +11 +00:00:32,800 --> 00:00:36,235 +example, you know you can use those dashed blue lines when + +12 +00:00:36,237 --> 00:00:38,871 +you drag things in and move things around to kinda tell + +13 +00:00:38,873 --> 00:00:42,441 +Xcode what you intend about how things are laid out, okay? + +14 +00:00:42,443 --> 00:00:45,444 +But you know that those blue lines are really only just + +15 +00:00:45,446 --> 00:00:48,247 +kind of a hint, right? But you can say reset to + +16 +00:00:48,249 --> 00:00:51,016 +suggest a constraints. And it'll use the dashed blue line + +17 +00:00:51,018 --> 00:00:54,753 +information to try and guess, what constraints you want. + +18 +00:00:54,755 --> 00:00:58,590 +And sometimes that's what you want, sometimes not. Really + +19 +00:00:58,592 --> 00:01:03,228 +that's just minimal help from the system to do Autolayout. + +20 +00:01:03,230 --> 00:01:04,663 +It's kinda maybe to get you started, + +21 +00:01:04,665 --> 00:01:06,865 +or to get some initial constraints or + +22 +00:01:06,867 --> 00:01:08,200 +something like that, okay? And + +23 +00:01:08,202 --> 00:01:11,136 +you know that you can look in the Size Inspector, okay? + +24 +00:01:11,138 --> 00:01:12,304 +You can click, click on any view and + +25 +00:01:12,306 --> 00:01:13,505 +look in the Size Inspector, and now, + +26 +00:01:13,507 --> 00:01:16,075 +now, down there you'll see all of the constraints. + +27 +00:01:16,077 --> 00:01:20,612 +We've looked at those before that are on a particular view. + +28 +00:01:20,614 --> 00:01:24,716 +Okay, you also know that you can click on a constraint + +29 +00:01:24,718 --> 00:01:27,619 +itself and look at it in the Attributes Inspector. + +30 +00:01:27,621 --> 00:01:29,988 +So just like we click on a view and inspect that, + +31 +00:01:29,990 --> 00:01:31,757 +you can click on any constraint, + +32 +00:01:31,759 --> 00:01:33,692 +like a little i-beam or, you know, some bar, + +33 +00:01:33,694 --> 00:01:36,628 +something that's connecting something to an edge or + +34 +00:01:36,630 --> 00:01:38,630 +something. You can click on those things. + +35 +00:01:38,632 --> 00:01:40,099 +You can even double-click on them and + +36 +00:01:40,101 --> 00:01:41,733 +edit them kind of in a little window. + +37 +00:01:41,735 --> 00:01:42,768 +But you can single-click on them and + +38 +00:01:42,770 --> 00:01:46,271 +then edit them in the Attributes Inspector as well. + +39 +00:01:47,108 --> 00:01:50,509 +Now we know that the other way, another way we can set, + +40 +00:01:50,511 --> 00:01:53,212 +constraints is to control drag like we control drag to + +41 +00:01:53,214 --> 00:01:56,515 +the edge and say, you know, make it be a certain distance + +42 +00:01:56,517 --> 00:01:58,750 +from this edge. Okay, we saw that quite a bit. + +43 +00:01:58,752 --> 00:02:01,720 +That Ctrl-dragging can also be done between views. + +44 +00:02:01,722 --> 00:02:04,123 +So you can Ctrl-drag between two views and then say, + +45 +00:02:04,125 --> 00:02:08,227 +make these two be the same with, okay? Things like that. + +46 +00:02:08,229 --> 00:02:10,529 +And we'll see a little bit of that today in the demo. So + +47 +00:02:10,531 --> 00:02:14,299 +that Ctrl-dragging is probably the number one way you do + +48 +00:02:14,301 --> 00:02:18,036 +Autolayout, okay? But there's also a couple of menus down in + +49 +00:02:18,038 --> 00:02:21,106 +the bottom right corner where that menu that you bring up + +50 +00:02:21,108 --> 00:02:25,110 +that says reset to suggested constraints or update frames. + +51 +00:02:25,112 --> 00:02:25,244 +You know that thing, + +52 +00:02:25,246 --> 00:02:27,846 +there's two other little menus right by it. Okay the pin and + +53 +00:02:27,848 --> 00:02:31,717 +arrange menus, and they also let you say things like + +54 +00:02:31,719 --> 00:02:34,720 +make these. You can select five views, and then bring up + +55 +00:02:34,722 --> 00:02:37,990 +the arrange menu and say, make all of these equal widths. + +56 +00:02:37,992 --> 00:02:39,992 +And now we have a constraint on all five of the views to + +57 +00:02:39,994 --> 00:02:44,830 +make them equal widths. So, those menus, frankly + +58 +00:02:44,832 --> 00:02:47,833 +you don't use them that much because the Ctrl-drag is so + +59 +00:02:47,835 --> 00:02:49,968 +incredibly convenient for doing that, but + +60 +00:02:49,970 --> 00:02:56,241 +sometimes we will. You can look at your constraints by + +61 +00:02:56,243 --> 00:02:59,378 +inspecting things, but really the way to see a big picture + +62 +00:02:59,380 --> 00:03:02,648 +of all of the constraints is in the document outline, okay? + +63 +00:03:02,650 --> 00:03:04,950 +Remember the document outline? That's the thing on the left + +64 +00:03:04,952 --> 00:03:06,251 +in the storyboard that you can kinda + +65 +00:03:06,253 --> 00:03:07,953 +bring out with the little button on the bottom and + +66 +00:03:07,955 --> 00:03:11,123 +it shows you all your views and the hierarchy of it and + +67 +00:03:11,125 --> 00:03:11,156 +all that stuff. + +68 +00:03:11,158 --> 00:03:14,059 +Well it'll also show all your constraints in there. Okay, + +69 +00:03:14,061 --> 00:03:15,994 +a big long list of your constraints. + +70 +00:03:15,996 --> 00:03:19,331 +And, that's a good place where you can go to see them. + +71 +00:03:19,333 --> 00:03:22,734 +It also has a constraint resolution + +72 +00:03:22,736 --> 00:03:25,337 +UI which I might have brief, briefly shown but + +73 +00:03:25,339 --> 00:03:28,340 +I'll certainly show today. Where it'll actually tell you + +74 +00:03:28,342 --> 00:03:30,642 +all the constraints that are conflicting or + +75 +00:03:30,644 --> 00:03:33,378 +not fully specifying things, that kind of stuff. + +76 +00:03:33,380 --> 00:03:36,148 +So it's kind of, Document Outline is your constraint + +77 +00:03:36,150 --> 00:03:39,484 +headquarters to go try and fix things with constraints and + +78 +00:03:39,486 --> 00:03:42,454 +understand what's going on with your constraints. Now + +79 +00:03:42,456 --> 00:03:45,624 +mastering Autolayout requires experience. I can tell you all + +80 +00:03:45,626 --> 00:03:49,194 +these things what the, what the things you can do are, but + +81 +00:03:49,196 --> 00:03:52,231 +until you get in there and start trying to lay things out + +82 +00:03:52,233 --> 00:03:55,801 +and make things line up, and do things like that, + +83 +00:03:55,803 --> 00:03:57,536 +you really won't be able to master it, okay? + +84 +00:03:57,538 --> 00:03:59,571 +So it requires experience. So hopefully in your final + +85 +00:03:59,573 --> 00:04:02,241 +project you'll have some UIs that require quite a bit of + +86 +00:04:02,243 --> 00:04:04,977 +Autolayout. You know the UIs we've had so far have not + +87 +00:04:04,979 --> 00:04:07,079 +required that much Autolayout because I haven't gotten to + +88 +00:04:07,081 --> 00:04:09,781 +this lecture yet. So you know we've been using StatView + +89 +00:04:09,783 --> 00:04:12,317 +a lot, okay? We're heavily relying on StatView to make it + +90 +00:04:12,319 --> 00:04:15,187 +so we don't have to do so much Autolayout, cuz StatView kind + +91 +00:04:15,189 --> 00:04:18,457 +of is a thing for doing Autolayout in a very simple + +92 +00:04:18,459 --> 00:04:22,361 +way when you want to line things up in grids, okay? So + +93 +00:04:22,363 --> 00:04:26,498 +there's no, no substitute for experience in Autolayout. It + +94 +00:04:26,500 --> 00:04:29,868 +is possible to do Autolayout constraints from code, okay? + +95 +00:04:29,870 --> 00:04:33,272 +There is a class called ns layout constraint. And + +96 +00:04:33,274 --> 00:04:36,041 +it does all the things you can do in the storyboard and + +97 +00:04:36,043 --> 00:04:38,277 +possibly even a little bit more. + +98 +00:04:38,279 --> 00:04:40,078 +Actually definitely a little bit more. + +99 +00:04:40,080 --> 00:04:41,913 +I'm not gonna teach that in this course. + +100 +00:04:41,915 --> 00:04:44,549 +If you wanna learn about it, you might think about trying + +101 +00:04:44,551 --> 00:04:48,987 +to do something in your final project, maybe. It requires + +102 +00:04:48,989 --> 00:04:51,923 +a certain understanding of mathematics and + +103 +00:04:51,925 --> 00:04:54,259 +really understanding relationships between things, + +104 +00:04:54,261 --> 00:04:56,962 +to really set things up and make things work. It's a heck + +105 +00:04:56,964 --> 00:04:59,631 +of a lot easier just to do it all in the story board. So + +106 +00:04:59,633 --> 00:05:02,067 +unless you wanna kinda make that one of your investigative + +107 +00:05:02,069 --> 00:05:04,303 +things for your final project, which you're gonna see + +108 +00:05:04,305 --> 00:05:06,104 +is required that you go investigate something that I + +109 +00:05:06,106 --> 00:05:09,541 +don't teach in lecture. You're probably gonna wanna try and + +110 +00:05:09,543 --> 00:05:12,711 +do Autolayout from the story board, okay. And + +111 +00:05:12,713 --> 00:05:15,814 +you can certainly do everything you need to do + +112 +00:05:15,816 --> 00:05:19,251 +almost all the time in your story board. Okay, + +113 +00:05:19,253 --> 00:05:24,656 +so, let's see what's next here. Let's talk about, + +114 +00:05:24,658 --> 00:05:30,195 +rotation, okay? So sometimes, when you rotate your UI, + +115 +00:05:30,197 --> 00:05:33,098 +the geometry of it changes so drastically that + +116 +00:05:33,100 --> 00:05:36,668 +Autolayout is not enough to reposition everything, okay? + +117 +00:05:36,670 --> 00:05:39,738 +A great example of this is our calculator, okay? Our + +118 +00:05:39,740 --> 00:05:43,775 +calculator had five across, five buttons across and + +119 +00:05:43,777 --> 00:05:47,913 +four buttons down, I think, okay? And that looked fine. + +120 +00:05:47,915 --> 00:05:49,948 +Or it was four across and five down, I guess. + +121 +00:05:49,950 --> 00:05:50,982 +And that looks fine in portrait. + +122 +00:05:50,984 --> 00:05:53,552 +All the buttons were almost square. They were rectangular, + +123 +00:05:53,554 --> 00:05:55,420 +but they were close to being square. But + +124 +00:05:55,422 --> 00:05:56,121 +when we went into landscape, + +125 +00:05:56,123 --> 00:05:58,390 +all of our buttons got really squished down, okay. + +126 +00:05:58,392 --> 00:06:01,393 +They're really wide and really short. Okay, and really, it + +127 +00:06:01,395 --> 00:06:04,363 +would have been a lot better if we had gone five across and + +128 +00:06:04,365 --> 00:06:06,832 +four down. Because we'd have more space + +129 +00:06:06,834 --> 00:06:09,735 +across than we do have down in landscape. Okay, well there's + +130 +00:06:09,737 --> 00:06:13,238 +no way to do Autolayout. No way so that that would happen. + +131 +00:06:13,240 --> 00:06:16,675 +Okay, there's no way to put any relationships between them + +132 +00:06:16,677 --> 00:06:18,210 +so that they would just somehow flip over. + +133 +00:06:18,212 --> 00:06:20,979 +Some of the buttons would flip over from being along the top, + +134 +00:06:20,981 --> 00:06:23,448 +for example, to being along the left, okay? So you can't + +135 +00:06:23,450 --> 00:06:26,051 +do it that way. So what would you do if you wanted to build + +136 +00:06:26,053 --> 00:06:29,588 +a calculator that repositioned the buttons when you flipped + +137 +00:06:29,590 --> 00:06:32,424 +it over? Because it's not just the calculate, + +138 +00:06:32,426 --> 00:06:35,327 +the calculator that might want to do this. For + +139 +00:06:35,329 --> 00:06:39,297 +you example you know when you're in the master of + +140 +00:06:39,299 --> 00:06:43,101 +a split view okay it's not you're not in portrait. + +141 +00:06:43,103 --> 00:06:44,236 +You're probably on an iPad or + +142 +00:06:44,238 --> 00:06:47,973 +at least you might be on an iPhone 6+. In that master, + +143 +00:06:47,975 --> 00:06:51,309 +you also want it to be the right arrangement of buttons. + +144 +00:06:51,311 --> 00:06:54,513 +Okay, more like iPhone portrait, okay, than iPad. + +145 +00:06:54,515 --> 00:06:58,784 +Okay, so the solution to doing this is called size classes. + +146 +00:06:58,786 --> 00:07:00,685 +Okay, so your view controllers, + +147 +00:07:00,687 --> 00:07:02,020 +any view controller that you're doing, + +148 +00:07:02,022 --> 00:07:02,988 +like the calculator view controller, + +149 +00:07:02,990 --> 00:07:06,691 +always lives in a size class environment, okay, for + +150 +00:07:06,693 --> 00:07:10,896 +its width and its height. Okay, and that size class is + +151 +00:07:10,898 --> 00:07:14,466 +either compact or regular. Regular means + +152 +00:07:14,468 --> 00:07:18,270 +it's not compact, okay? So your view controller for each, + +153 +00:07:18,272 --> 00:07:21,206 +for horizontally and vertically, will get something + +154 +00:07:21,208 --> 00:07:25,177 +told to it, okay you are in a compact vertical environment, + +155 +00:07:25,179 --> 00:07:28,680 +or you are in a compact horizontal environment. And + +156 +00:07:28,682 --> 00:07:31,983 +you can react to that, okay? So in the calculator's case, + +157 +00:07:31,985 --> 00:07:34,352 +if we're in a compact vertical environment, + +158 +00:07:34,354 --> 00:07:38,256 +let's put five across and four down, because we're squi, + +159 +00:07:38,258 --> 00:07:40,192 +you know, squished down vertically so + +160 +00:07:40,194 --> 00:07:43,228 +we'll spread them out a little bit. And if we're not, + +161 +00:07:43,230 --> 00:07:46,498 +then we'll go ahead and use the vertical space and make it + +162 +00:07:46,500 --> 00:07:50,001 +be four across and five down, okay? So getting all this, + +163 +00:07:50,003 --> 00:07:53,405 +kind of all the different kinds of aspect ratios, and + +164 +00:07:53,407 --> 00:07:56,942 +things for all the devices to fit into this compact in + +165 +00:07:56,944 --> 00:07:59,277 +regular. You know it's not a perfect fit, but + +166 +00:07:59,279 --> 00:08:02,380 +here's a kind of general idea of how these fit, all right? + +167 +00:08:02,382 --> 00:08:06,651 +So the iPhone 6 Plus in Portrait, right when it's, + +168 +00:08:06,653 --> 00:08:09,855 +it's stand, standing upright basically. + +169 +00:08:09,857 --> 00:08:14,025 +That is compact width, regular height. Makes perfect sense, + +170 +00:08:14,027 --> 00:08:15,894 +right? Okay, compact width, regular height. + +171 +00:08:15,896 --> 00:08:18,697 +When you go to Landscape, now it's compact height, + +172 +00:08:18,699 --> 00:08:22,801 +regular width. Okay. So iPhone 6 Plus makes the most sense of + +173 +00:08:22,803 --> 00:08:28,240 +all of the devices. Okay? Now iPhone non-plus, + +174 +00:08:28,242 --> 00:08:32,944 +okay, is compact, in width. + +175 +00:08:32,946 --> 00:08:35,413 +Sorry, in Portrait, it's compact in width and + +176 +00:08:35,415 --> 00:08:37,649 +regular in height. But in Landscaped, okay, + +177 +00:08:37,651 --> 00:08:39,885 +non 6 Plus now I'm talking about here, it's + +178 +00:08:39,887 --> 00:08:44,422 +compact in both directions. So on a normal iPhone, non plus + +179 +00:08:44,424 --> 00:08:47,726 +iPhone, in width, you would think it would be regular + +180 +00:08:47,728 --> 00:08:50,495 +cuz it was regular when it was in Portrait in height, but no, + +181 +00:08:50,497 --> 00:08:53,431 +it's compact. So you can actually tell the difference + +182 +00:08:53,433 --> 00:08:57,736 +between whether you're on a 6 Plus or a regular iPhone 4 or + +183 +00:08:57,738 --> 00:09:00,705 +S or 5 or 6 or whatever, non Plus because you'll + +184 +00:09:00,707 --> 00:09:03,241 +be compact in both directions in Landscape. Okay? + +185 +00:09:03,243 --> 00:09:06,011 +So it's just kinda weird gotta be used to that. + +186 +00:09:06,013 --> 00:09:10,015 +iPad is always regular in both directions. Cuz it£s so big, + +187 +00:09:10,017 --> 00:09:13,351 +it£s not compact in any way, in any direction. However, + +188 +00:09:13,353 --> 00:09:16,821 +if you£re an MVC that is in the master of a split view, + +189 +00:09:16,823 --> 00:09:21,226 +you£ll be compact in width. Okay, understandably right cuz + +190 +00:09:21,228 --> 00:09:27,265 +you're kinda, jammed in there. This whole system, + +191 +00:09:27,267 --> 00:09:31,136 +by the way, is extensible. It's not just rock solid, + +192 +00:09:31,138 --> 00:09:34,372 +you know, hooked up to whether you're on a 6 Plus or + +193 +00:09:34,374 --> 00:09:36,474 +an iPhone or in a split view master or + +194 +00:09:36,476 --> 00:09:38,476 +a whatever. It has a whole mechanism for + +195 +00:09:38,478 --> 00:09:42,781 +an MVC to find out what size class it's in. It can even say + +196 +00:09:42,783 --> 00:09:45,650 +based on its environment I wanna be in this size class. + +197 +00:09:45,652 --> 00:09:48,687 +And then if it has MVCs inside of it like it's a navigation + +198 +00:09:48,689 --> 00:09:49,354 +controller or something like that. + +199 +00:09:49,356 --> 00:09:52,724 +Then they would inherit that size class information, okay. + +200 +00:09:52,726 --> 00:09:56,328 +Now I'm not gonna talk about that all the code side of it. + +201 +00:09:56,330 --> 00:09:59,097 +The only code you're probably gonna be interested + +202 +00:09:59,099 --> 00:10:01,232 +in is this method here in view controller, + +203 +00:10:01,234 --> 00:10:04,736 +Self traitCollection. Horizontal size class and + +204 +00:10:04,738 --> 00:10:05,503 +vertical size class and + +205 +00:10:05,505 --> 00:10:07,672 +it's gonna give you back compact irregular. + +206 +00:10:07,674 --> 00:10:09,641 +Okay? So that's how you'll know if you're compact + +207 +00:10:09,643 --> 00:10:12,844 +irregular. Now, that's only if you wanted to react + +208 +00:10:12,846 --> 00:10:15,947 +to your compactness in code. A lot of times we're gonna + +209 +00:10:15,949 --> 00:10:19,217 +be doing this in our story board. Okay? And I'm gonna + +210 +00:10:19,219 --> 00:10:21,686 +show you how in the story board we'll react to that. So + +211 +00:10:21,688 --> 00:10:24,589 +in summary it looks like this, okay? You got compact width + +212 +00:10:24,591 --> 00:10:26,491 +and regular width. Compact height and regular height. + +213 +00:10:26,493 --> 00:10:30,462 +So, iPhones (non-Plus) in Landscape are here. Compact, + +214 +00:10:30,464 --> 00:10:35,567 +compact. Regular width compact is iPhone 6 Plus in Landscape. + +215 +00:10:35,569 --> 00:10:36,234 +Regular height and + +216 +00:10:36,236 --> 00:10:38,470 +compact width is iPhones in Portrait or + +217 +00:10:38,472 --> 00:10:40,772 +you're the Master of the Split View. And + +218 +00:10:40,774 --> 00:10:44,009 +then iPads are regular in both. Okay. So, + +219 +00:10:44,011 --> 00:10:45,443 +if you want to look at the calculator, for example, + +220 +00:10:45,445 --> 00:10:49,180 +it would look something like this, all right. Now here is, + +221 +00:10:49,182 --> 00:10:53,718 +I'm drawing my UI here as if I've adapted to this. In + +222 +00:10:53,720 --> 00:10:57,255 +in this case right here, I've decided to go four across and + +223 +00:10:57,257 --> 00:11:00,191 +five down because I gotta lot of down, a lot of vertical + +224 +00:11:00,193 --> 00:11:02,761 +space. Whereas here I've gone five across and + +225 +00:11:02,763 --> 00:11:04,663 +four down cuz I'm kinda compact in height, + +226 +00:11:04,665 --> 00:11:07,699 +you see. Even here I've done the same thing. + +227 +00:11:07,701 --> 00:11:09,200 +I've decided here, compact and + +228 +00:11:09,202 --> 00:11:11,970 +regular width to go five across and four down. And + +229 +00:11:11,972 --> 00:11:14,539 +down here, in regular both directions I decided it + +230 +00:11:14,541 --> 00:11:19,244 +looks a little better to have the four across and five down. + +231 +00:11:19,246 --> 00:11:24,015 +Okay? Now you would imagine if I wanted my calculator to work + +232 +00:11:24,017 --> 00:11:27,318 +this way I might have to build fi, four different UIs, one, + +233 +00:11:27,320 --> 00:11:30,321 +two, three, four. For all four of these. Okay, and + +234 +00:11:30,323 --> 00:11:32,657 +that would normally be the way it is. + +235 +00:11:32,659 --> 00:11:35,760 +Except for that, we actually do size classes with a little + +236 +00:11:35,762 --> 00:11:38,797 +more subtlety than that. Because if you look here, + +237 +00:11:38,799 --> 00:11:41,866 +compact height always is five across and + +238 +00:11:41,868 --> 00:11:43,968 +four down. Whether it's compact width or + +239 +00:11:43,970 --> 00:11:45,303 +regular width, doesn't matter. And + +240 +00:11:45,305 --> 00:11:48,573 +here, in regular height, it's always four across, + +241 +00:11:48,575 --> 00:11:50,542 +five down, no matter what the width. So + +242 +00:11:50,544 --> 00:11:52,343 +really I should only have to do two things here, + +243 +00:11:52,345 --> 00:11:55,413 +okay, based on the height. I shouldn't have to do anything + +244 +00:11:55,415 --> 00:11:59,851 +different based on the width. And that's why the whole size + +245 +00:11:59,853 --> 00:12:03,388 +class thing is actually treated as a grid like this. + +246 +00:12:03,390 --> 00:12:05,790 +With nine things in it and in the middle you + +247 +00:12:05,792 --> 00:12:09,894 +have this special width and height called any. Okay. So + +248 +00:12:09,896 --> 00:12:11,996 +now if I want what I had on the previous screen, + +249 +00:12:11,998 --> 00:12:15,900 +all I have to do is two UIs. One for regular height, + +250 +00:12:15,902 --> 00:12:19,571 +any width, and one for compact height, any width. And + +251 +00:12:19,573 --> 00:12:23,842 +even better than that, I can actually put some of my UI + +252 +00:12:23,844 --> 00:12:27,312 +here in the middle, any height, any width. And + +253 +00:12:27,314 --> 00:12:31,483 +only put the differences out here in these other two. So + +254 +00:12:31,485 --> 00:12:34,352 +this the part of the UI that's the same on both right, + +255 +00:12:34,354 --> 00:12:36,855 +I got the display and I've got this part of the keypad. + +256 +00:12:36,857 --> 00:12:39,424 +It's the same on both. And it's only that piece that's + +257 +00:12:39,426 --> 00:12:42,527 +either gonna be here or here okay that is different. + +258 +00:12:42,529 --> 00:12:45,864 +And that's all I'm gonna have to do in these two things. All + +259 +00:12:45,866 --> 00:12:49,434 +right? So, we just add this idea of this any width and + +260 +00:12:49,436 --> 00:12:53,738 +any height to make a nine way thing. And I, in your story + +261 +00:12:53,740 --> 00:12:56,908 +board, you can actually go to any of these nine squares and + +262 +00:12:56,910 --> 00:13:00,411 +edit the UI. Okay? And that's what we're gonna show in our + +263 +00:13:00,413 --> 00:13:03,148 +demo here. Okay? So, I'm gonna do this calculator thing, + +264 +00:13:03,150 --> 00:13:05,850 +exactly what I just showed there. And + +265 +00:13:05,852 --> 00:13:09,521 +we'll see what it looks like to the size class business + +266 +00:13:09,523 --> 00:13:12,857 +in Xcode. Okay so here we are in calculator. + +267 +00:13:12,859 --> 00:13:15,326 +This is how we left off in calculator. + +268 +00:13:15,328 --> 00:13:16,761 +Actually it's a little different cuz I this is + +269 +00:13:16,763 --> 00:13:18,863 +the version before we did that save restore. So + +270 +00:13:18,865 --> 00:13:21,733 +I don't have save restore. So otherwise it's just a normal + +271 +00:13:21,735 --> 00:13:24,702 +calculator thing here. I'm gonna start right off + +272 +00:13:24,704 --> 00:13:28,173 +by noticing that I have this warning up here. You see this, + +273 +00:13:28,175 --> 00:13:30,708 +this yellow triangle that's all over the place here. + +274 +00:13:30,710 --> 00:13:32,977 +Telling me about warnings. What are this warnings? + +275 +00:13:32,979 --> 00:13:36,181 +If I click them, it's the old frame will be different at + +276 +00:13:36,183 --> 00:13:40,018 +run time. You guys, I'm sure, are well acquainted with that. + +277 +00:13:40,020 --> 00:13:43,188 +That you get it all the time, when you're doing auto layout + +278 +00:13:43,190 --> 00:13:45,824 +stuff. And you know the fix to this? Anyone wanna tell me + +279 +00:13:45,826 --> 00:13:50,461 +what the fix for this is? What do I do? Go down here, + +280 +00:13:50,463 --> 00:13:54,899 +right. Select this view controller. Go down here and + +281 +00:13:54,901 --> 00:13:59,637 +say update frames, right. Okay let's try it. + +282 +00:14:00,373 --> 00:14:04,676 +No. It didn't work. What's going on here? Okay, so + +283 +00:14:04,678 --> 00:14:06,978 +have you seen this? Where you do this update frames and + +284 +00:14:06,980 --> 00:14:09,347 +it doesn't work. I'm sure some of you have seen that as well. + +285 +00:14:09,349 --> 00:14:12,150 +Okay, well I'm gonna show you another way to fix this, okay, + +286 +00:14:12,152 --> 00:14:15,253 +which is also not going to work. In the document outline, + +287 +00:14:15,255 --> 00:14:16,921 +so here's our document outline right here. + +288 +00:14:16,923 --> 00:14:19,524 +You see this? I told you the document outline is + +289 +00:14:19,526 --> 00:14:22,393 +kinda the headquarters for constraints. In fact, + +290 +00:14:22,395 --> 00:14:25,396 +here's all my constraints, okay? + +291 +00:14:25,398 --> 00:14:27,966 +Look at this little guy right here, this little button. + +292 +00:14:27,968 --> 00:14:31,069 +This is telling me there's a problem with your constraints. + +293 +00:14:31,071 --> 00:14:32,871 +And you can actually click on this little button, + +294 +00:14:32,873 --> 00:14:36,140 +which I'm going to do. And it'll show you all the places, + +295 +00:14:36,142 --> 00:14:38,076 +all the misplaced views in this case. + +296 +00:14:38,078 --> 00:14:38,810 +It's going around showing them, + +297 +00:14:38,812 --> 00:14:41,813 +I can even highlight them as I mouse over them. + +298 +00:14:41,815 --> 00:14:44,582 +And you can even fix them, if you click on this little + +299 +00:14:44,584 --> 00:14:46,818 +triangle, right here. It'll come up and + +300 +00:14:46,820 --> 00:14:49,787 +you can do update frames to fix this. You can try and + +301 +00:14:49,789 --> 00:14:52,090 +update the constraints to match what's here. + +302 +00:14:52,092 --> 00:14:55,093 +I recommend against that, generally Because it's gonna + +303 +00:14:55,095 --> 00:14:56,728 +put hardwired constraints in there to try and + +304 +00:14:56,730 --> 00:14:59,964 +hold that thing in position. That's usually not what you + +305 +00:14:59,966 --> 00:15:03,201 +want. You can also reset to suggested constraints here. + +306 +00:15:03,203 --> 00:15:06,070 +That might be something you want sometimes if you know + +307 +00:15:06,072 --> 00:15:07,305 +that you put it on the blue lines, + +308 +00:15:07,307 --> 00:15:09,307 +but usually you want to try and update frames. + +309 +00:15:09,309 --> 00:15:11,309 +And you can even apply it too all the views in + +310 +00:15:11,311 --> 00:15:14,145 +the container, cuz we know we got five problems right here. + +311 +00:15:14,147 --> 00:15:17,849 +So, I can click those and hit fix displacement here, and + +312 +00:15:17,851 --> 00:15:22,253 +that should fix it. Nope, it didn't, okay. Now, I'm not + +313 +00:15:22,255 --> 00:15:25,723 +exactly sure why those either of those things didn't fix it. + +314 +00:15:25,725 --> 00:15:29,027 +It should've. But I'm gonna show you a tricky way, + +315 +00:15:29,029 --> 00:15:31,496 +to fix this misplacement problem. + +316 +00:15:31,498 --> 00:15:34,032 +Would you just pick up something, okay, + +317 +00:15:34,034 --> 00:15:37,368 +that's misplaced like this, and just put it back down + +318 +00:15:37,370 --> 00:15:42,507 +where you think it's supposed to be. Okay? Voila, okay? + +319 +00:15:42,509 --> 00:15:42,674 +some reason that causes the entire constraint system to + +320 +00:15:42,676 --> 00:15:45,610 +Because for + +321 +00:15:45,612 --> 00:15:48,746 +reevaluate everything's in the right spot, no issues, see? + +322 +00:15:48,748 --> 00:15:52,450 +No auto layout issues here, no yellow buttons up here. Okay? + +323 +00:15:52,452 --> 00:15:55,019 +So that's a real nice little trick to know, okay? + +324 +00:15:55,021 --> 00:15:59,657 +Just pick the thing up and put it back down in the right + +325 +00:15:59,659 --> 00:16:03,861 +place, might fix everything All right, okay. + +326 +00:16:03,863 --> 00:16:07,432 +So let's talk about our calculator here. + +327 +00:16:07,434 --> 00:16:10,868 +Our calculator wants to use size classes so that instead + +328 +00:16:10,870 --> 00:16:14,072 +of being four across and five down like this, okay, in + +329 +00:16:14,074 --> 00:16:18,209 +compact situations, it's gonna be five across and four down. + +330 +00:16:18,211 --> 00:16:21,512 +So I told you there's those nine little spots? + +331 +00:16:21,514 --> 00:16:23,214 +Here they are, right here, right down at the bottom. + +332 +00:16:23,216 --> 00:16:27,552 +See this W Any H Any? That tells you you're editing with + +333 +00:16:27,554 --> 00:16:30,455 +any height, any. And if you click on this, + +334 +00:16:30,457 --> 00:16:33,524 +it'll show you all nine of those areas, okay? + +335 +00:16:33,526 --> 00:16:37,328 +Just mouse over them. So the middle one is any, any, okay. + +336 +00:16:37,330 --> 00:16:41,199 +Up here, this is compact height, any width. + +337 +00:16:41,201 --> 00:16:45,336 +This down here is regular height, any width, okay? + +338 +00:16:45,338 --> 00:16:48,072 +Here is compact width, compact height. + +339 +00:16:48,074 --> 00:16:50,341 +So if I were to click on this and + +340 +00:16:50,343 --> 00:16:56,014 +go edit that UI, what device would this, that ui be on? + +341 +00:16:56,016 --> 00:16:56,781 +>> iPhone 6. + +342 +00:16:56,783 --> 00:16:56,848 +>> iPhone 6, + +343 +00:16:56,850 --> 00:17:00,852 +in landscape, right? Or iPhone 5 in landscape also, okay? + +344 +00:17:00,854 --> 00:17:01,853 +Cuz that's the only one that's compact. So + +345 +00:17:01,855 --> 00:17:06,557 +this is actually specifically choosing a non-plus iPhone, + +346 +00:17:06,559 --> 00:17:09,527 +okay? So you can pick any of these positions that you want. + +347 +00:17:09,529 --> 00:17:13,931 +Now we know in our calculator that the compact height, one, + +348 +00:17:13,933 --> 00:17:18,036 +okay, is the one that we wanna move these buttons down to + +349 +00:17:18,038 --> 00:17:21,172 +the side over here. Okay, here's a compact height. + +350 +00:17:21,174 --> 00:17:24,409 +Now, I'm gonna show you a feature here that you might + +351 +00:17:24,411 --> 00:17:26,577 +be inclined to use with size classes, + +352 +00:17:26,579 --> 00:17:28,079 +but it's not gonna work for us. + +353 +00:17:28,081 --> 00:17:31,215 +Okay, but I wanna show you how it works, which is, + +354 +00:17:31,217 --> 00:17:34,786 +I might just start by saying let's at first, at least get + +355 +00:17:34,788 --> 00:17:38,856 +rid of these four buttons when we're in this compact version, + +356 +00:17:38,858 --> 00:17:41,659 +okay? See here we're in width any, height compact. We're + +357 +00:17:41,661 --> 00:17:45,296 +editing this UI. Changes that we make in here are only going + +358 +00:17:45,298 --> 00:17:49,700 +to apply to this size class, okay, which is compact height. + +359 +00:17:49,702 --> 00:17:51,035 +Any time we're in a compact height. + +360 +00:17:51,037 --> 00:17:53,538 +Now, we can only make certain changes in here, like, + +361 +00:17:53,540 --> 00:17:56,040 +we couldn't inspect objects and change their color. + +362 +00:17:56,042 --> 00:17:59,143 +That's not gonna work. But we can remove and add views, + +363 +00:17:59,145 --> 00:18:03,247 +and most importantly, we can change constraints, okay? + +364 +00:18:03,249 --> 00:18:03,881 +Those are the things we can do. + +365 +00:18:03,883 --> 00:18:06,484 +So I said we can remove and add views, how would we remove + +366 +00:18:06,486 --> 00:18:09,320 +this stack view? Let's say we don't want this x divide plus + +367 +00:18:09,322 --> 00:18:11,522 +minus stack here, we just don't want it in there. + +368 +00:18:11,524 --> 00:18:13,291 +Well, we can go over to the Inspector, okay, and + +369 +00:18:13,293 --> 00:18:16,294 +inspect this thing. And look down at the very bottom, okay? + +370 +00:18:16,296 --> 00:18:18,029 +This is just the Inspector for the stack view. + +371 +00:18:18,031 --> 00:18:21,599 +And the bottom, it says right here, Installed with a check. + +372 +00:18:21,601 --> 00:18:26,070 +That means it's installed in all size classes. + +373 +00:18:26,072 --> 00:18:28,973 +And if we didn't want it installed in this one, + +374 +00:18:28,975 --> 00:18:31,375 +we can actually click this little plus, and + +375 +00:18:31,377 --> 00:18:34,812 +pick this size class, which is with any height compact, + +376 +00:18:34,814 --> 00:18:38,549 +or we could actually pick any other one we wanted, okay? + +377 +00:18:38,551 --> 00:18:41,185 +So we can pick any combination we want. + +378 +00:18:41,187 --> 00:18:42,687 +Since this is the one we're editing, it's, + +379 +00:18:42,689 --> 00:18:44,455 +the kind of the first choice right here, any width, + +380 +00:18:44,457 --> 00:18:47,692 +compact, height. So I'm gonna pick that. And when I pick + +381 +00:18:47,694 --> 00:18:50,795 +that, it breaks that one out. It's still installed, but + +382 +00:18:50,797 --> 00:18:52,830 +it breaks that one out with any height compact. + +383 +00:18:52,832 --> 00:18:56,868 +But if I click this off, it will no longer install this + +384 +00:18:56,870 --> 00:19:00,371 +view in this size class. So now anytime I'm running in + +385 +00:19:00,373 --> 00:19:03,407 +a modern environment where it's compact, that view, + +386 +00:19:03,409 --> 00:19:06,444 +that stack view's not even gonna be there. Okay, + +387 +00:19:06,446 --> 00:19:11,015 +if I go back to any any here, it's still there, + +388 +00:19:11,017 --> 00:19:15,753 +okay. It's only in this compact height that it's gone. + +389 +00:19:15,755 --> 00:19:20,758 +So let's go run and see if this is working for us. + +390 +00:19:26,900 --> 00:19:29,167 +All right, here we go. It's five high and + +391 +00:19:29,169 --> 00:19:32,603 +four wide in portrait. Looks good, okay. Hopefully, + +392 +00:19:32,605 --> 00:19:35,506 +if we go to landscape, which we know is compact height, + +393 +00:19:35,508 --> 00:19:39,243 +it should get rid of those four buttons, right? It did! + +394 +00:19:39,245 --> 00:19:41,712 +Excellent, see, this size class stuff works. + +395 +00:19:41,714 --> 00:19:45,683 +And now we'll just go back over to portrait. Oops, okay, + +396 +00:19:45,685 --> 00:19:49,720 +look what happened there. When I went back to portrait, + +397 +00:19:49,722 --> 00:19:53,124 +it tried to put that stack view back, but the size class + +398 +00:19:53,126 --> 00:19:57,128 +system can't put things back into other view hierarchies, + +399 +00:19:57,130 --> 00:19:59,430 +you can only put it back at the top level. + +400 +00:19:59,432 --> 00:20:02,934 +So it couldn't do that, so it decided to put it back, and + +401 +00:20:02,936 --> 00:20:05,436 +just put it back as 0,0 up there, okay? + +402 +00:20:05,438 --> 00:20:07,338 +So that's clearly not what we want, + +403 +00:20:07,340 --> 00:20:08,673 +that's clearly not gonna work. So + +404 +00:20:08,675 --> 00:20:12,276 +we need a different strategy, but I just wanted to show you + +405 +00:20:12,278 --> 00:20:15,713 +there is this feature where you can use this mechanism to + +406 +00:20:15,715 --> 00:20:19,417 +decide that certain views exist in certain places, okay? + +407 +00:20:19,419 --> 00:20:21,919 +And you're gonna see this is gonna automatically happen + +408 +00:20:21,921 --> 00:20:24,855 +when we start putting views in different kinds of views, + +409 +00:20:24,857 --> 00:20:26,591 +vertical stack views and things like that. + +410 +00:20:26,593 --> 00:20:29,193 +You'll see that this will automatically be happening for + +411 +00:20:29,195 --> 00:20:32,930 +us. So I'm gonna undo here, get that thing back, okay? + +412 +00:20:32,932 --> 00:20:38,302 +So let's get this back in our width any horizontal compact. + +413 +00:20:38,304 --> 00:20:38,769 +So that's not gonna work. + +414 +00:20:38,771 --> 00:20:42,807 +So what could we do instead? All right, well, since I + +415 +00:20:42,809 --> 00:20:46,310 +know I can't have this thing inside this stack view, right, + +416 +00:20:46,312 --> 00:20:49,380 +working, I'm gonna have to pull it out. I'm gonna have to + +417 +00:20:49,382 --> 00:20:51,916 +pull all of these things out of the stack view. So let's + +418 +00:20:51,918 --> 00:20:55,353 +just do that, okay? I'm just going to move this thing. And + +419 +00:20:55,355 --> 00:20:57,588 +actually, you know what? I'm gonna do all this in any any. + +420 +00:20:57,590 --> 00:21:01,158 +Because when I think about it, I can't have this here in any + +421 +00:21:01,160 --> 00:21:04,195 +any, otherwise, it's always gonna appear there. + +422 +00:21:04,197 --> 00:21:07,531 +Okay, in other ones, and I don't want it there, + +423 +00:21:07,533 --> 00:21:08,466 +on the top in compact, so + +424 +00:21:08,468 --> 00:21:12,036 +I'm gonna take this whole stack view right here, okay? + +425 +00:21:12,038 --> 00:21:14,905 +This one, the one that I don't want here, and + +426 +00:21:14,907 --> 00:21:18,976 +I'm going to just delete it, hit cut to delete it. Okay, so + +427 +00:21:18,978 --> 00:21:21,779 +now in the any any, that means on all size classes, + +428 +00:21:21,781 --> 00:21:25,616 +that thing is gone. It's not there. And what's more, + +429 +00:21:25,618 --> 00:21:28,252 +I'm going to take this stack view right here, and + +430 +00:21:28,254 --> 00:21:29,687 +I'm gonna pull the things out of it. + +431 +00:21:29,689 --> 00:21:33,491 +So for example, I'm gonna pull the display out of it, okay, + +432 +00:21:33,493 --> 00:21:36,460 +I'm gonna take this inner stack view right here and + +433 +00:21:36,462 --> 00:21:39,897 +pull it out, leaving this empty stack view, okay? Which + +434 +00:21:39,899 --> 00:21:43,668 +we don't even need anymore, so I'm gonna delete it, okay? + +435 +00:21:43,670 --> 00:21:48,539 +So now, this is all part of all size classes, + +436 +00:21:48,541 --> 00:21:52,643 +right? This is in all size classes. In the compact case, + +437 +00:21:52,645 --> 00:21:57,048 +it's this with buttons down here. And in the regular case, + +438 +00:21:57,050 --> 00:22:00,851 +it's this with some buttons along here. We all agree with + +439 +00:22:00,853 --> 00:22:04,789 +that? So in any any, we always wanna build as much of the UI + +440 +00:22:04,791 --> 00:22:08,859 +as we can that we know applies to all size classes, okay? + +441 +00:22:08,861 --> 00:22:11,696 +So this one, we know that this is gonna go + +442 +00:22:11,698 --> 00:22:14,732 +in the corner down here, right? And + +443 +00:22:14,734 --> 00:22:19,103 +we also know that this goes up at the top, + +444 +00:22:19,105 --> 00:22:23,107 +right? And we can even do the constraints here, or at + +445 +00:22:23,109 --> 00:22:26,877 +least some of the constraints. I'm gonna go down here and + +446 +00:22:26,879 --> 00:22:30,381 +reset all of our constraints by picking Clear Constraints + +447 +00:22:30,383 --> 00:22:33,084 +in the same place you Update Frames and all that. + +448 +00:22:33,086 --> 00:22:36,120 +I'm gonna Clear Constraints to get all these constraints out + +449 +00:22:36,122 --> 00:22:38,656 +of here, and now I'm gonna put new constraints in. + +450 +00:22:38,658 --> 00:22:41,258 +Now this part is exactly what you're used to, + +451 +00:22:41,260 --> 00:22:44,128 +I'm just going to Ctrl + Drag to the edge here and + +452 +00:22:44,130 --> 00:22:47,832 +hook up that trailing space. I'm gonna Ctrl + Drag to + +453 +00:22:47,834 --> 00:22:50,801 +the bottom down here, okay, at the bottom. + +454 +00:22:50,803 --> 00:22:55,573 +I'm gonna, for the display up here, Ctrl + Drag to the top, + +455 +00:22:55,575 --> 00:22:58,142 +Ctrl + Drag to the leading edge, okay? + +456 +00:22:58,144 --> 00:23:03,013 +Ctrl + Drag to the right edge, okay? So look, no errors, + +457 +00:23:03,015 --> 00:23:06,016 +no auto-layout issues over here in my document outline. + +458 +00:23:06,018 --> 00:23:08,919 +No little yellow thing, so everything is perfectly fine. + +459 +00:23:08,921 --> 00:23:10,588 +I can even run right now. Let's run and + +460 +00:23:10,590 --> 00:23:17,495 +see what happens. Okay, so here it is in portrait. Okay, + +461 +00:23:17,497 --> 00:23:20,398 +it's doing what we want, which is this down in the corner, + +462 +00:23:20,400 --> 00:23:20,998 +this up here. Of course, + +463 +00:23:21,000 --> 00:23:23,868 +I haven't added the buttons that I want right here. + +464 +00:23:23,870 --> 00:23:26,470 +And how about in landscape? It's working here too. + +465 +00:23:26,472 --> 00:23:29,140 +Of course, I haven't added the buttons here, all right? + +466 +00:23:29,142 --> 00:23:31,275 +So it's putting the display in the right space. + +467 +00:23:31,277 --> 00:23:33,010 +It's keeping these buttons over in the corner. + +468 +00:23:33,012 --> 00:23:37,882 +So this is great, okay? It's all working fine so far. + +469 +00:23:37,884 --> 00:23:41,385 +Now let's go and fix the two size classes. So let's start + +470 +00:23:41,387 --> 00:23:44,422 +with compact height, okay. In compact type, actually let's + +471 +00:23:44,424 --> 00:23:46,290 +start with regular height cuz it's the similar, + +472 +00:23:46,292 --> 00:23:47,725 +the most similar to the other one we have. + +473 +00:23:47,727 --> 00:23:50,227 +So here's regular height. Unfortunately, it's so + +474 +00:23:50,229 --> 00:23:52,730 +big I have to scroll up and down, but in this one, + +475 +00:23:52,732 --> 00:23:55,266 +we basically just want to put, take these things. + +476 +00:23:55,268 --> 00:23:57,435 +I just pasted them back, I had cut them before, and + +477 +00:23:57,437 --> 00:24:01,972 +we just to put it right here. Okay, right along the top. + +478 +00:24:01,974 --> 00:24:03,274 +Now the problem here though, + +479 +00:24:03,276 --> 00:24:06,243 +is that we need to put some constraints to make it be + +480 +00:24:06,245 --> 00:24:10,114 +the same as the rest of those buttons in the stack view. + +481 +00:24:10,116 --> 00:24:13,317 +Right? So, how are we gonna do that? Well there's a couple + +482 +00:24:13,319 --> 00:24:14,752 +of different ways that we can do it. + +483 +00:24:14,754 --> 00:24:16,954 +1. Is with these menus down here I told you about so + +484 +00:24:16,956 --> 00:24:22,126 +I'm gonna select this one so these two views are selected, + +485 +00:24:22,128 --> 00:24:24,228 +this whole big stack view here, and + +486 +00:24:24,230 --> 00:24:26,163 +this stack view here. And we're gonna go down here, and + +487 +00:24:26,165 --> 00:24:29,967 +we're gonna look at these alignment and pin menus. So + +488 +00:24:29,969 --> 00:24:33,938 +here's an alignment one. We can do thing here to, for + +489 +00:24:33,940 --> 00:24:37,842 +example, align the edges of these things. So it might make + +490 +00:24:37,844 --> 00:24:41,412 +a lot of sense to take this guy and have his leading and + +491 +00:24:41,414 --> 00:24:44,949 +trailing edges aligned with this one, right? So + +492 +00:24:44,951 --> 00:24:47,284 +let's try that I'm just going to turn on leading and + +493 +00:24:47,286 --> 00:24:48,986 +trailing edges here to align those. + +494 +00:24:48,988 --> 00:24:51,155 +I could also align things like the horizontal center, + +495 +00:24:51,157 --> 00:24:55,926 +vertical centers, I could horizontally in the containers + +496 +00:24:55,928 --> 00:24:58,929 +centered in the container etcetera. But I'm going to do + +497 +00:24:58,931 --> 00:25:01,799 +it, but also notice it's going to align the leading edges + +498 +00:25:01,801 --> 00:25:05,369 +with no delta. It's just like right along the leading edge. + +499 +00:25:05,371 --> 00:25:07,705 +So I'm going to add those two constraints. Okay. + +500 +00:25:07,707 --> 00:25:08,439 +It's added the constraints. + +501 +00:25:08,441 --> 00:25:11,275 +Now what's interesting here is now these + +502 +00:25:11,277 --> 00:25:14,545 +constraint complaints are red not yellow red. + +503 +00:25:14,547 --> 00:25:17,381 +And why is that? Okay, let's go over here and look at this. + +504 +00:25:17,383 --> 00:25:20,217 +And it says vertical position is ambiguous for + +505 +00:25:20,219 --> 00:25:24,488 +stack view, okay? It says it over here as well in my docu-, + +506 +00:25:24,490 --> 00:25:24,655 +no-, outline. + +507 +00:25:24,657 --> 00:25:28,125 +It's saying this guy has no vertical position to find. And + +508 +00:25:28,127 --> 00:25:30,995 +in fact, that's true. There, it's just floating there. + +509 +00:25:30,997 --> 00:25:33,063 +There's nothing that says where it is vertically. + +510 +00:25:33,065 --> 00:25:34,598 +We've defined where it is horizontally, + +511 +00:25:34,600 --> 00:25:36,834 +but we haven't defined where it is vertically. So + +512 +00:25:36,836 --> 00:25:40,838 +to do that, I'm gonna re-, go back to our Ctrl-drag, okay? + +513 +00:25:40,840 --> 00:25:43,107 +So I'm just gonna Ctrl-drag from this one to this one, + +514 +00:25:43,109 --> 00:25:46,977 +and this time, I'm gonna put Vertical spacing, okay? + +515 +00:25:46,979 --> 00:25:50,114 +Now he's got vertical spacing, so now his problem's right + +516 +00:25:50,116 --> 00:25:53,684 +here, are just the frames are not, are wrong, okay. And + +517 +00:25:53,686 --> 00:25:56,954 +again, I could pick up this thing right here and try and + +518 +00:25:56,956 --> 00:26:00,324 +put it there. I can take this, put it down here, you know, + +519 +00:26:00,326 --> 00:26:01,125 +try and move things back or + +520 +00:26:01,127 --> 00:26:04,161 +I could do update frames, but we're not done yet + +521 +00:26:04,163 --> 00:26:08,299 +either with this. Because there we fix the width + +522 +00:26:08,301 --> 00:26:11,268 +to be the same width as this cuz we align the edges but + +523 +00:26:11,270 --> 00:26:14,572 +what about the height, okay. We need the height of this row + +524 +00:26:14,574 --> 00:26:17,241 +to be exactly the same height as all these rows. And + +525 +00:26:17,243 --> 00:26:21,378 +it's perfectly legal for us to do that by going control drag, + +526 +00:26:21,380 --> 00:26:24,515 +okay, from this guy down to this guy. And + +527 +00:26:24,517 --> 00:26:28,118 +then saying that we want them to be equal heights. + +528 +00:26:28,120 --> 00:26:31,589 +Okay? See that Equal Heights? Okay, so + +529 +00:26:31,591 --> 00:26:36,060 +now they're gonna be equal heights. So you see how we've + +530 +00:26:36,062 --> 00:26:38,996 +put this thing basically and really stack view does a very + +531 +00:26:38,998 --> 00:26:41,131 +similar thing to what we're doing right here, okay,. + +532 +00:26:41,133 --> 00:26:43,367 +When you said all things like fill and fill equally, + +533 +00:26:43,369 --> 00:26:45,502 +it's making equal heights and all that stuff. + +534 +00:26:45,504 --> 00:26:45,736 +But unfortunately, + +535 +00:26:45,738 --> 00:26:49,206 +we had to move this stack view out because it doesn't exist, + +536 +00:26:49,208 --> 00:26:52,843 +in some of the size classes. All right, so + +537 +00:26:52,845 --> 00:26:53,143 +we're not quite done, + +538 +00:26:53,145 --> 00:26:55,713 +because we still want this thing to fill the whole space, + +539 +00:26:55,715 --> 00:26:59,116 +right? We want this nice block that we've built to fill this + +540 +00:26:59,118 --> 00:27:02,219 +whole space. So I'm gonna do exact same thing we did + +541 +00:27:02,221 --> 00:27:05,389 +before which is control drag okay from the edge of this. + +542 +00:27:05,391 --> 00:27:08,025 +And make it leading space, right be fixed here. + +543 +00:27:08,027 --> 00:27:10,728 +I'm gonna double click on it, try to make it standard. + +544 +00:27:10,730 --> 00:27:15,332 +That's not available so I'll go zero. Okay, makes it wide. + +545 +00:27:15,334 --> 00:27:15,666 +And same thing here. + +546 +00:27:15,668 --> 00:27:17,134 +I wanna make the distance between here and + +547 +00:27:17,136 --> 00:27:20,838 +here be a standard distance so let's do that. Control drag. + +548 +00:27:20,840 --> 00:27:24,308 +And down to here and this is the vertical spacing right + +549 +00:27:24,310 --> 00:27:27,544 +here. Okay, which makes this beam. Double click on that + +550 +00:27:27,546 --> 00:27:30,481 +and of course when we click on it it's also showing over here + +551 +00:27:30,483 --> 00:27:31,382 +not just in this little window, but + +552 +00:27:31,384 --> 00:27:35,285 +it's over here as well. And here standard is available. + +553 +00:27:35,287 --> 00:27:38,689 +Okay, so we can do standard height. Okay, so + +554 +00:27:38,691 --> 00:27:42,393 +this looks pretty good. In the regular height situation, + +555 +00:27:42,395 --> 00:27:45,129 +we've got four wide and five high. + +556 +00:27:45,131 --> 00:27:52,703 +So let's go into run, see if it worked. All right, + +557 +00:27:52,705 --> 00:27:54,371 +here it is, four wide and five high. Okay, + +558 +00:27:54,373 --> 00:27:58,208 +let's go to landscape. Perfect we don't want four wide and + +559 +00:27:58,210 --> 00:28:00,844 +five high there so we're just getting the any any + +560 +00:28:00,846 --> 00:28:05,516 +situation right back to here and is back. Okay so + +561 +00:28:05,518 --> 00:28:08,318 +it's working fine. And now, what we need to do is the same + +562 +00:28:08,320 --> 00:28:11,488 +thing we just did for regular for compact. Okay so + +563 +00:28:11,490 --> 00:28:15,426 +let's go to that we do that by going to this little nine grid + +564 +00:28:15,428 --> 00:28:18,862 +here we're going up to compact height any width. And + +565 +00:28:18,864 --> 00:28:22,099 +here we want that same thing right here, + +566 +00:28:22,101 --> 00:28:24,435 +but this time this has to be vertical. Okay. + +567 +00:28:24,437 --> 00:28:26,870 +So I'm just gonna go to the stack views inspector. + +568 +00:28:26,872 --> 00:28:27,871 +Here's the stack view inspecting it. + +569 +00:28:27,873 --> 00:28:31,275 +And I'm gonna make it vertical this time. Okay? + +570 +00:28:31,277 --> 00:28:34,278 +And I want to put it along here. Okay? + +571 +00:28:34,280 --> 00:28:36,847 +So I'm gonna use control drag to do it this time and + +572 +00:28:36,849 --> 00:28:40,784 +I can actually set up most of this using shift in here. + +573 +00:28:40,786 --> 00:28:43,420 +I think I told you before when this comes up You can actually + +574 +00:28:43,422 --> 00:28:47,024 +click multiple things, okay, with shift. So I can make it, + +575 +00:28:47,026 --> 00:28:51,495 +for example, the horizontal spacing, the top, the bottom. + +576 +00:28:51,497 --> 00:28:53,697 +I can line those all up. Okay? Now, + +577 +00:28:53,699 --> 00:28:55,899 +I don't actually want this to be equal widths, because I + +578 +00:28:55,901 --> 00:28:58,335 +don't want this to be the same width as this whole thing. + +579 +00:28:58,337 --> 00:29:00,170 +So, I'm going to have to do equal widths, + +580 +00:29:00,172 --> 00:29:03,540 +by making this the same width as one of these buttons. Okay. + +581 +00:29:03,542 --> 00:29:06,110 +So we do that to set those. So I'm gonna Control drag + +582 +00:29:06,112 --> 00:29:07,711 +from here to one of these buttons and + +583 +00:29:07,713 --> 00:29:11,181 +do Equal Widths, okay, so that this will be the same width. + +584 +00:29:11,183 --> 00:29:14,718 +Of course, we've got this whole frames are wrong, + +585 +00:29:14,720 --> 00:29:16,086 +so this time, just to be different, + +586 +00:29:16,088 --> 00:29:17,955 +I'll go up here and click one of these and + +587 +00:29:17,957 --> 00:29:22,292 +apply to all views in container. Fix it. Okay. So + +588 +00:29:22,294 --> 00:29:24,194 +now, we've got it there where we want it. Again, + +589 +00:29:24,196 --> 00:29:28,465 +same thing here. We want to put a vertical spacing + +590 +00:29:28,467 --> 00:29:32,970 +constraint here. Okay, we'll do standard if available, + +591 +00:29:32,972 --> 00:29:37,841 +yep. Okay, and same thing over here. We will put this to + +592 +00:29:37,843 --> 00:29:43,113 +the leading edge and again, no standard. Sorry, + +593 +00:29:43,115 --> 00:29:49,186 +so we'll do zero. Okay, there we go. We've got five wide, + +594 +00:29:49,188 --> 00:29:53,590 +four high in this compact situation, all right? + +595 +00:29:53,592 --> 00:29:59,596 +So let's run that. Okay, + +596 +00:29:59,598 --> 00:30:02,499 +here it is, portrait, looking good, landscape, + +597 +00:30:02,501 --> 00:30:07,037 +looking good. Okay, + +598 +00:30:07,606 --> 00:30:11,809 +any questions about that? Make sense? All right, now I wanna + +599 +00:30:11,811 --> 00:30:15,012 +show you a couple of things about what we've wrought here. + +600 +00:30:15,014 --> 00:30:18,182 +One thing is let's look at this stack view right here. + +601 +00:30:18,184 --> 00:30:21,285 +Look at it's installed state down there. See that? + +602 +00:30:21,287 --> 00:30:25,823 +It's not installed in any any. It's only installed in any + +603 +00:30:25,825 --> 00:30:28,559 +with compact height. That's exactly what we want. So + +604 +00:30:28,561 --> 00:30:31,862 +see how it automatically did this when we pasted this one + +605 +00:30:31,864 --> 00:30:35,132 +in? Any time we add a view to the size class, it's going to + +606 +00:30:35,134 --> 00:30:39,036 +automatically do this install magic for you here. Okay? + +607 +00:30:39,038 --> 00:30:42,472 +Now another think I told you was that the document outline + +608 +00:30:42,474 --> 00:30:44,942 +is kind of your constraint central. Okay? + +609 +00:30:44,944 --> 00:30:47,711 +So let's understand what the document outline is telling us + +610 +00:30:47,713 --> 00:30:52,649 +about constraints here okay? Here's all our constraints and + +611 +00:30:52,651 --> 00:30:54,985 +notice that some of them are grayed out and + +612 +00:30:54,987 --> 00:30:57,654 +some of them are dark blue. See that? + +613 +00:30:57,656 --> 00:31:00,157 +Well, as you might imagine the grayed out ones + +614 +00:31:00,159 --> 00:31:03,327 +are constraints that only apply in other size classes. + +615 +00:31:03,329 --> 00:31:06,363 +That don't apply here. So since this is any width + +616 +00:31:06,365 --> 00:31:09,499 +compact height, we're not seeing any of the constraints + +617 +00:31:09,501 --> 00:31:12,870 +that have to do with any width regular heigth. + +618 +00:31:12,872 --> 00:31:13,136 +if I switch over okay watch these carefully right here. + +619 +00:31:13,138 --> 00:31:14,972 +Okay? But, + +620 +00:31:14,974 --> 00:31:17,174 +You're gonna see some of these are gonna go like right and + +621 +00:31:17,176 --> 00:31:19,309 +some of these are gonna go dark blue. Okay. + +622 +00:31:19,311 --> 00:31:23,780 +So I'm gonna switch down here to any width, regular height. + +623 +00:31:23,782 --> 00:31:25,215 +Which has different constraints. + +624 +00:31:25,217 --> 00:31:27,651 +You see how this changed? So you can always tell + +625 +00:31:27,653 --> 00:31:31,421 +which ones apply to you, okay, by which ones are dark. + +626 +00:31:31,423 --> 00:31:35,025 +Now another thing you wanna do when you are using constraints + +627 +00:31:35,027 --> 00:31:39,296 +is to go magic number hunting. Okay. You want to look at + +628 +00:31:39,298 --> 00:31:41,732 +these constraints and hunt for magic numbers and + +629 +00:31:41,734 --> 00:31:45,802 +get rid of them. Unless you really mean to have one. Okay, + +630 +00:31:45,804 --> 00:31:49,640 +very important. So in here let's find some magic numbers. + +631 +00:31:49,642 --> 00:31:53,610 +Okay. Here's one, 8, here's 282, 82, + +632 +00:31:53,612 --> 00:31:58,181 +88 and 20. So those are all of our magic numbers right there. + +633 +00:31:58,183 --> 00:32:01,118 +First thing you wanna do is, only you can only hunt for + +634 +00:32:01,120 --> 00:32:04,321 +magic numbers in the ones that are dark blue. Okay, + +635 +00:32:04,323 --> 00:32:08,725 +you can£t, these 282 is in some other constraint in some + +636 +00:32:08,727 --> 00:32:12,396 +other size class, so just ignore it here. It£s like + +637 +00:32:12,398 --> 00:32:15,966 +you£re not even seeing it. But this eight right here, okay? + +638 +00:32:15,968 --> 00:32:19,236 +This is the one we do need to look at, okay? Cuz we just + +639 +00:32:19,238 --> 00:32:21,905 +don't want this magic number here. So what is this one? + +640 +00:32:21,907 --> 00:32:25,976 +This is the display's top to the top layout guide's bottom. + +641 +00:32:25,978 --> 00:32:28,812 +It's this one right here. Okay, so that's eight. + +642 +00:32:28,814 --> 00:32:32,783 +Okay, let's go ahead and inspect this. We're inspecting + +643 +00:32:32,785 --> 00:32:35,452 +this constraint. And you can see that it's 8 and + +644 +00:32:35,454 --> 00:32:38,522 +really what you wanna change that to is standard value. + +645 +00:32:38,524 --> 00:32:40,590 +And when you change that to standard value, look. + +646 +00:32:40,592 --> 00:32:43,894 +The eight's gone, okay? Now you might ask, + +647 +00:32:43,896 --> 00:32:45,362 +where did that eight come in in the first place? + +648 +00:32:45,364 --> 00:32:48,899 +Well probably we dragged that thing to, and used a blue line + +649 +00:32:48,901 --> 00:32:52,736 +to do, to put it there. And it was eight points from the top. + +650 +00:32:52,738 --> 00:32:54,871 +And so when we added constraint, + +651 +00:32:54,873 --> 00:32:58,075 +it added it as eight. But what we really wanted was standard + +652 +00:32:58,077 --> 00:33:00,510 +distance. Okay, how about this one right here? + +653 +00:33:00,512 --> 00:33:03,313 +This is the stack view's top to the stack view bottom. + +654 +00:33:03,315 --> 00:33:06,984 +That's this one right here. Okay, uh-oh, [LAUGH] that one + +655 +00:33:06,986 --> 00:33:11,655 +is a magic number, but that's the wrong magic number. + +656 +00:33:11,657 --> 00:33:14,558 +Because what is the distance in all these other things. + +657 +00:33:14,560 --> 00:33:16,860 +In this stack view, what's the spacing? + +658 +00:33:16,862 --> 00:33:20,464 +It's ten, remember that? Okay? So, we want the space in + +659 +00:33:20,466 --> 00:33:24,001 +between these two stack views to also be ten. Okay? So + +660 +00:33:24,003 --> 00:33:26,169 +this constant wants to be a magic number and + +661 +00:33:26,171 --> 00:33:29,406 +it wants to be ten, and it truly is a magic number. Okay? + +662 +00:33:29,408 --> 00:33:30,140 +So we want that magic number, + +663 +00:33:30,142 --> 00:33:33,377 +because we intended it to be a magic number. + +664 +00:33:33,379 --> 00:33:36,179 +All right? How about this one? 20. + +665 +00:33:36,181 --> 00:33:38,782 +Okay, stack view bottom right here. That one also, + +666 +00:33:38,784 --> 00:33:42,386 +we probably don't want that to be a non-standard value, so + +667 +00:33:42,388 --> 00:33:45,689 +I'm just gonna pick Standard Value, okay? + +668 +00:33:45,691 --> 00:33:49,726 +And we'll do the same thing in our other size classes, + +669 +00:33:49,728 --> 00:33:52,195 +so we'll go here. This one right here has + +670 +00:33:52,197 --> 00:33:54,297 +this Stack View.leading to Stack View.trailing, + +671 +00:33:54,299 --> 00:33:56,600 +that's right here, see it highlighted right there? + +672 +00:33:56,602 --> 00:34:00,437 +That wants to be ten. What else have we got here? + +673 +00:34:00,439 --> 00:34:02,773 +Anything else? No? All the rest of these are good? + +674 +00:34:02,775 --> 00:34:05,842 +And don't forget any any when you do these things. + +675 +00:34:05,844 --> 00:34:07,044 +So go to any any. Now it looks good. + +676 +00:34:07,046 --> 00:34:11,248 +They're all good. Okay, so I have no magic numbers now. So + +677 +00:34:11,250 --> 00:34:13,083 +my UI is all nice and arranged. + +678 +00:34:13,085 --> 00:34:15,118 +Now why do we wanna get rid of these magic numbers? + +679 +00:34:15,120 --> 00:34:18,889 +Because the built-in numbers, the standard numbers, + +680 +00:34:18,891 --> 00:34:20,090 +are gonna be the same in every single app, + +681 +00:34:20,092 --> 00:34:22,492 +not just your app. So when people are running other apps, + +682 +00:34:22,494 --> 00:34:25,028 +things are gonna look similar, similar spacing, etc. And + +683 +00:34:25,030 --> 00:34:27,564 +that's what you want, cuz you want a consistent experience, + +684 +00:34:27,566 --> 00:34:31,001 +not just inside your own app, but within you know, + +685 +00:34:31,003 --> 00:34:36,940 +two other apps, as well. What else did I want to show here? + +686 +00:34:36,942 --> 00:34:41,945 +We talked about insufficient constraints, + +687 +00:34:41,947 --> 00:34:47,084 +we talked about, okay. Conflicting constraints. + +688 +00:34:47,086 --> 00:34:49,086 +Sometimes you'll have conflicting constraints, like + +689 +00:34:49,088 --> 00:34:51,488 +two different constraints that are trying to constrain the + +690 +00:34:51,490 --> 00:34:55,525 +same two things and they'll be across size classes. + +691 +00:34:55,527 --> 00:34:58,061 +Those can be sometimes hard to find. Okay, + +692 +00:34:58,063 --> 00:35:00,497 +let's say I have my calculator app here. Okay, + +693 +00:35:00,499 --> 00:35:02,699 +I'm looking at any any here and I go away for + +694 +00:35:02,701 --> 00:35:05,268 +a few months and I come back and I look at this, and + +695 +00:35:05,270 --> 00:35:08,305 +I forget the fact that I had these other side classes over + +696 +00:35:08,307 --> 00:35:12,042 +here. And I look at this and I'm like, my gosh, I forgot to + +697 +00:35:12,044 --> 00:35:15,712 +control drag this up to the top. No, I better do that. + +698 +00:35:15,714 --> 00:35:18,381 +Okay vertical spacing and I better put this thing over + +699 +00:35:18,383 --> 00:35:22,919 +here my lead spacing. Yeah, well have to fix that let's + +700 +00:35:22,921 --> 00:35:27,958 +make this be zero and we'll fix this and we'll + +701 +00:35:27,960 --> 00:35:32,529 +make this one be a standard. Okay whew, I fixed it. Okay, + +702 +00:35:32,531 --> 00:35:36,500 +everything's good. Look I have no conflicting constraints. + +703 +00:35:36,502 --> 00:35:38,435 +I must have fixed my app, it's in good shape. + +704 +00:35:38,437 --> 00:35:41,805 +So let's go ahead and run it. I'm sure it looks really good. + +705 +00:35:45,844 --> 00:35:49,980 +What the, okay, that one's okay but what a mess. + +706 +00:35:49,982 --> 00:35:51,014 +What the heck happened here? And look, + +707 +00:35:51,016 --> 00:35:53,083 +I'm getting all kinds of warnings on my console, + +708 +00:35:53,085 --> 00:35:56,853 +conflicting constraints. You know what, so I've totally + +709 +00:35:56,855 --> 00:35:59,623 +broken the world, even though when I go back into my app, + +710 +00:35:59,625 --> 00:36:02,726 +it looks like everything fine. That's because when you change + +711 +00:36:02,728 --> 00:36:04,861 +constraints, especially when you change any any, + +712 +00:36:04,863 --> 00:36:08,265 +you wanna go take a look at your other size classes. Now, + +713 +00:36:08,267 --> 00:36:11,768 +when we look at that. [SOUND] Two views are horizontally + +714 +00:36:11,770 --> 00:36:15,739 +ambiguous. Three conflicting constraints. If we go down + +715 +00:36:15,741 --> 00:36:20,477 +to this one down here, we got four conflicting constraints. + +716 +00:36:20,479 --> 00:36:23,580 +When you have conflicting constraints, this little + +717 +00:36:23,582 --> 00:36:26,616 +yellow thing up here will actually turn red, okay? And + +718 +00:36:26,618 --> 00:36:28,952 +then you can click on that and see all the conflicts. + +719 +00:36:28,954 --> 00:36:30,687 +So these things are all conflicting, and + +720 +00:36:30,689 --> 00:36:32,322 +of course these conflict, okay? + +721 +00:36:32,324 --> 00:36:33,356 +We know why these conflict. + +722 +00:36:33,358 --> 00:36:37,394 +Because in any any, we've fixed the edges of this stack + +723 +00:36:37,396 --> 00:36:40,797 +view to some things. And in the other size classes, we've + +724 +00:36:40,799 --> 00:36:45,468 +also fixed the edges of these, this thing to other things. + +725 +00:36:45,470 --> 00:36:49,272 +Okay, like to this thing over here, for example. So + +726 +00:36:49,274 --> 00:36:54,744 +be careful about that when you have, when you're putting your + +727 +00:36:54,746 --> 00:36:57,080 +constraints in there, it might look like everything's fine, + +728 +00:36:57,082 --> 00:36:58,248 +but you could have conflicts across. + +729 +00:36:58,250 --> 00:37:03,186 +So I'm gonna undo all this. To go back here. All right, + +730 +00:37:03,188 --> 00:37:06,590 +another thing I want to show you is + +731 +00:37:06,592 --> 00:37:09,159 +just to kind of prove to you what we were talking + +732 +00:37:09,161 --> 00:37:12,229 +about with the compact width being on some platforms + +733 +00:37:12,231 --> 00:37:15,232 +not others, I'm actually gonna go up here to a different one + +734 +00:37:15,234 --> 00:37:18,802 +which is this guy right here. This is compact width + +735 +00:37:18,804 --> 00:37:21,905 +any height. That's what this square is. I'm gonna click on + +736 +00:37:21,907 --> 00:37:23,406 +that. So here's compact width any height. + +737 +00:37:23,408 --> 00:37:25,742 +Notice that it looks like any any because we haven't done + +738 +00:37:25,744 --> 00:37:28,845 +anything special in here. And I'm actually gonna drag + +739 +00:37:28,847 --> 00:37:32,115 +a button out. Okay, here's a button. I'm gonna drag it. + +740 +00:37:32,117 --> 00:37:34,384 +I'm gonna call this button, actually, we'll just do it + +741 +00:37:34,386 --> 00:37:36,920 +with a label. We don't need a button, this label here, + +742 +00:37:36,922 --> 00:37:40,323 +and we'll call this thing Compact Width. + +743 +00:37:40,325 --> 00:37:42,659 +Cuz we're putting this in the compact width any, + +744 +00:37:42,661 --> 00:37:46,830 +right? Then I'll even put it right here in the middle. + +745 +00:37:46,832 --> 00:37:49,032 +I'll do another control drag so you can see constraints. + +746 +00:37:49,034 --> 00:37:52,402 +So, I'm gonna control drag to my super view, okay, and + +747 +00:37:52,404 --> 00:37:56,806 +say center this vertically in the container. So + +748 +00:37:56,808 --> 00:37:58,742 +now it's gonna center this. So now when I run, + +749 +00:37:58,744 --> 00:38:03,346 +okay, any time I'm appearing on a compact width situation, + +750 +00:38:03,348 --> 00:38:04,547 +it's gonna say compact width. So + +751 +00:38:04,549 --> 00:38:07,250 +sure enough, this one, that's compact width, right? + +752 +00:38:07,252 --> 00:38:09,452 +We know iPhone 6 and portrait is compact width. + +753 +00:38:09,454 --> 00:38:13,056 +And here, this is also compact width cuz this is iPhone 6 not + +754 +00:38:13,058 --> 00:38:17,427 +6 Plus, iPhone 6 in landscape is also compact width, okay? + +755 +00:38:17,429 --> 00:38:19,329 +Now we know this is compact height, because look, + +756 +00:38:19,331 --> 00:38:23,633 +our times divide plus minus are not along the sides so + +757 +00:38:23,635 --> 00:38:23,967 +it's compact height. And + +758 +00:38:23,969 --> 00:38:26,836 +we know this is regular height because those things are on + +759 +00:38:26,838 --> 00:38:30,440 +the top. Okay, now let's go look at this on 6 Plus. + +760 +00:38:38,583 --> 00:38:42,719 +All right, so 6 Plus portrait is compact width, + +761 +00:38:42,721 --> 00:38:46,089 +okay. In landscape, not compact width. + +762 +00:38:46,091 --> 00:38:51,261 +It's regular width. All right? But this height is the same. + +763 +00:38:51,263 --> 00:38:54,397 +This is compact height because these are not along the top. + +764 +00:38:54,399 --> 00:38:58,068 +And this is regular height because these are the top. + +765 +00:38:58,270 --> 00:39:01,371 +Okay, let's take a look at iPad. + +766 +00:39:12,417 --> 00:39:16,186 +All right, so iPad, not compact width in portrait, + +767 +00:39:16,188 --> 00:39:20,423 +also not compact width in landscape. And it's + +768 +00:39:20,425 --> 00:39:24,194 +regular in height because, see these buttons on the top? + +769 +00:39:24,196 --> 00:39:27,931 +In landscape and it's regular in height in portrait as well. + +770 +00:39:27,933 --> 00:39:31,134 +So regular in both directions. Both landscape and portrait. + +771 +00:39:31,136 --> 00:39:32,369 +Okay now I'm gonna do something here, + +772 +00:39:32,371 --> 00:39:34,971 +I'm gonna go back to the calculator here and + +773 +00:39:34,973 --> 00:39:38,575 +I'm gonna put it in a split view. Okay? + +774 +00:39:38,577 --> 00:39:40,610 +So this is my calculator here, I'm gonna pop this thing into + +775 +00:39:40,612 --> 00:39:43,613 +split view,so let's grab a split view. I'm gonna make + +776 +00:39:43,615 --> 00:39:45,915 +this calculator be the master of the split view. + +777 +00:39:45,917 --> 00:39:50,186 +There is the split view. I'm to, delete this and this. + +778 +00:39:50,188 --> 00:39:53,189 +And I'm just gonna make this be the entry point, right? + +779 +00:39:53,191 --> 00:39:55,325 +This split view is gonna be the entry point. And then I'll + +780 +00:39:55,327 --> 00:39:59,763 +make this be the master. Okay? So now let's run on iPad and + +781 +00:39:59,765 --> 00:40:05,402 +see what we got. Okay. + +782 +00:40:05,404 --> 00:40:08,738 +Here we go. This is portrait. Here's landscape. + +783 +00:40:08,740 --> 00:40:12,142 +Okay notice or my calculator is compact width + +784 +00:40:12,144 --> 00:40:14,711 +when it's even if it's on iPad. But it's still compact + +785 +00:40:14,713 --> 00:40:17,180 +width because it's in the master here. Here's a really + +786 +00:40:17,182 --> 00:40:20,016 +interesting one. What happens if I'm in portrait and + +787 +00:40:20,018 --> 00:40:25,588 +I pull the master out? Not compact width. Okay + +788 +00:40:25,590 --> 00:40:29,426 +not compact width, even though it's the exact same width + +789 +00:40:29,428 --> 00:40:32,362 +okay as in landscape. It's not compact width, and that's + +790 +00:40:32,364 --> 00:40:34,397 +because there's actually API in the split view what when + +791 +00:40:34,399 --> 00:40:37,267 +you put that thing out it can pull out different distances. + +792 +00:40:37,269 --> 00:40:40,437 +And rather than have them try to be changing the size class + +793 +00:40:40,439 --> 00:40:43,706 +on the fly, sometimes it's compact, sometimes regular. + +794 +00:40:43,708 --> 00:40:45,442 +They just said, okay, + +795 +00:40:45,444 --> 00:40:49,412 +because it lets you tell these two different states, okay? + +796 +00:40:49,414 --> 00:40:52,682 +Whether you're in the landscape as the master or + +797 +00:40:52,684 --> 00:40:55,218 +you're pulled out as the master, okay? + +798 +00:40:55,220 --> 00:41:00,056 +Everyone got that? Okay, so that's it, for size classes, + +799 +00:41:00,058 --> 00:41:04,394 +that's it for auto layout. Again, only experience will + +800 +00:41:04,396 --> 00:41:06,362 +really teach you auto layout in the long run, + +801 +00:41:06,364 --> 00:41:08,031 +but you know where all the pieces of it are now, + +802 +00:41:08,033 --> 00:41:10,166 +and you know how to do control drag. + +803 +00:41:10,168 --> 00:41:12,735 +That's probably the main thing you're gonna be doing. + +804 +00:41:12,737 --> 00:41:14,270 +And maybe you'll be doing these menus down here, + +805 +00:41:14,272 --> 00:41:20,477 +possibly. Okay, Friday, no section again on this Friday. + +806 +00:41:20,479 --> 00:41:22,912 +Monday your current assignment is coordinate a smash tag + +807 +00:41:22,914 --> 00:41:27,116 +is due. There will be another assignment, Assignment 6 going + +808 +00:41:27,118 --> 00:41:30,787 +out next week. Not sure, probably gonna go out on + +809 +00:41:30,789 --> 00:41:33,756 +Wednesday. It might go out on Wednesday, not 100% sure. + +810 +00:41:33,758 --> 00:41:36,125 +I'll think about it over the week can't okay but + +811 +00:41:36,127 --> 00:41:38,728 +the topic of that assignment and in the topic of next + +812 +00:41:38,730 --> 00:41:41,598 +week's lectures is gonna be animation. Okay, a very + +813 +00:41:41,600 --> 00:41:45,101 +important part obviously building an app on iOS and + +814 +00:41:45,103 --> 00:41:49,939 +that's it. So I'll be here I'm here if you have questions as + +815 +00:41:49,941 --> 00:41:53,710 +usual, that kind of business. >> For + +816 +00:41:53,712 --> 00:41:53,743 +more please visit us at Stanford.edu. + From 7443c7ae3dfea95888c8858a853aac7e8a97067b Mon Sep 17 00:00:00 2001 From: saitjr Date: Mon, 26 Sep 2016 23:11:03 +0800 Subject: [PATCH 10/23] finish 1-500 in 8. Multithreading and Text Field --- .../8. Multithreading and Text Field.srt | 130 +++++++++++++++++- 1 file changed, 128 insertions(+), 2 deletions(-) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index b4162c3..a65d536 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -1870,7 +1870,7 @@ minimum extent we allow which is none, 1.0. So 375 00:19:36,976 --> 00:19:41,779 we need to set the maximum and minimum scrolling factor or -我们需要给 scrollView 的范围因子，或叫做 +我们需要给 scrollView 的范围因子，或叫做给 376 00:19:41,781 --> 00:19:45,583 @@ -1880,507 +1880,633 @@ zooming factor on this scrollView. So let's do that. 377 00:19:45,585 --> 00:19:48,386 Let's do that also right here when we're setting our - +在这里进行设置，在 378 00:19:48,388 --> 00:19:50,254 scrollView from our storyboard. So +scrollView 在 storyboard 中被赋值时调用的方法 379 00:19:50,256 --> 00:19:52,924 we just say that the scrollView's minimum zoom +键入 scrollView 的 minimumZoomScale 380 00:19:52,926 --> 00:19:57,962 scale. I'm gonna have this minimum zoom scale. +来设置最小缩放因子 381 00:19:57,964 --> 00:20:02,433 What did I think that worked well here? 0.03. +设成多少效果比较好呢？0.03 吧 382 00:20:02,435 --> 00:20:04,735 So we're gonna zoom- allowed to zoom way out. +我们可以进行缩放 383 00:20:04,737 --> 00:20:07,205 So it will make the image really small, okay? +图片会缩小到很小 384 00:20:07,207 --> 00:20:10,975 Three one-hundredths of it's size. +是原图的百分之三 385 00:20:10,977 --> 00:20:13,844 3% of its size. And then the maximum, +也就是 3% 的大小，接下来设置最大因子 386 00:20:13,846 --> 00:20:16,480 it is perfectly fine for us to say the maximum is 1.0. +这个值设为 1.0 就好了 387 00:20:16,482 --> 00:20:20,318 Maybe we never want the thing to be zoomed out any bigger +可能我们永远不会将该图片放大 388 00:20:20,320 --> 00:20:23,020 than it already is, especially there are huge images already. +毕竟它已经是一张很大的图片了 389 00:20:23,022 --> 00:20:26,190 So we can set the maximum to zoom scale. We don't even need +其实我们完全可以不用设置放大因子，这条 390 00:20:26,192 --> 00:20:29,060 to put this. Cuz by default, it's 1.0. But we'll put it +语句可以不用谢，因为默认值就是 1.0. 这里就不删了， 391 00:20:29,062 --> 00:20:32,430 in here just to kinda be very clear about what we're doing. +看着更清晰一点 392 00:20:32,432 --> 00:20:39,737 All right, so now lets try it. All right, +再来看看效果 393 00:20:39,739 --> 00:20:44,542 so lets go get Cassini right here. All right, here it is. +点击 Cassini，然后 394 00:20:44,544 --> 00:20:48,212 Lets zoom in on it, right. I'm pinching. Yeah, look at that, +进行缩放，捏合一下，看到了吧 395 00:20:48,214 --> 00:20:50,314 it's zooming. And sure enough, look, +缩小了. 效果很好 396 00:20:50,316 --> 00:20:54,352 there's Cassini. Taking a little trip by Saturn, okay, +这是 Cassini，在围着 Saturn 兜风 397 00:20:54,354 --> 00:20:57,021 let's zip it around here so we can see a little better. Okay, +旋转一下屏幕，就能看到更多内容 398 00:20:57,023 --> 00:21:00,324 how about some of these other images, go look at the Earth, +来看看其他图片呢，看看 Earch 399 00:21:00,493 --> 00:21:03,861 didn't look like much like Earth. Now if we zoom, +之前看着并不像 Earth. 这次缩小试试 400 00:21:03,863 --> 00:21:07,131 we'll see something here. All right, so here it is, +说不定能看到更多东西. 好了，加载出来了 401 00:21:07,133 --> 00:21:11,802 scrolling around, I'm gonna pinch, pinch some more. +滚动看看，然后捏合，再缩小点 402 00:21:11,804 --> 00:21:17,675 Look at this Earth, okay? Same thing with Saturn. +啊哈，这就是 Earch. 在看看 Saturn 呢 403 00:21:18,111 --> 00:21:20,244 Okay, everyone see what we do with the zooming? +每个人都知道怎么实现缩放了吗？ 404 00:21:20,246 --> 00:21:21,279 Zooming quite simple +实现起来真的很简单 405 00:21:21,281 --> 00:21:22,847 in terms of the code you have to write, but +就那么几句代码 406 00:21:22,849 --> 00:21:24,882 you have to understand that delegation piece for +这全都要靠 delegate 407 00:21:24,884 --> 00:21:28,152 it to really, to make it work. And you'll see Saturn, +那才是真谛. 来看看 Saturn 408 00:21:28,154 --> 00:21:34,325 there's Saturn. Okay? Now let's try this on iPad, +这是 Saturn. 没问题，运行在 iPad 上试试， 409 00:21:34,327 --> 00:21:37,528 okay? Let's see what it looks like here. +看看显示效果 410 00:21:47,373 --> 00:21:48,906 All right, so here is our master and +这是 master 411 00:21:48,908 --> 00:21:51,542 our detail right here. So if I click on Cassini, +这是 detail，点击 Cassini， 412 00:21:51,544 --> 00:21:54,912 hopefully Cassini will eventually really slow, +加载起来确实很慢 413 00:21:54,914 --> 00:21:57,315 appear right here. Okay? And we can zoom in here, okay? +显示出来了，缩放试试呢 414 00:21:57,317 --> 00:22:02,119 Now, what would be really cool here is if we could have +如果在这里能有个标题 415 00:22:02,121 --> 00:22:05,856 a title up here that said this was Cassini, +告诉我们这是 Cassini， 416 00:22:05,858 --> 00:22:09,560 or Earth, or Saturn, right? So remember +还是是 Earth，是 Saturn，就更好了 417 00:22:09,562 --> 00:22:12,863 the tricky way we did that, is we went to our storyboard, and +其实有一个很取巧的方式，打开 storyboard 418 00:22:12,865 --> 00:22:17,201 we just put this one down here. Also in the scrollView. +将下面的这个包含 scrollView 的控制器 419 00:22:17,203 --> 00:22:19,704 So we said embed in navigation control. +加上 navigation 420 00:22:19,706 --> 00:22:21,872 Or not in a scrollView, in a navigation controller. So +或者嵌入到 navigation controller 中 421 00:22:21,874 --> 00:22:25,910 I embed it in there, so that now I have a title. Right? And +嵌入之后，就可以设置标题了 422 00:22:25,912 --> 00:22:26,644 we know that if we can go and +如果现在运行 423 00:22:26,646 --> 00:22:29,547 run this, it's not going to work, right? Because these +不会有任何效果，因为 424 00:22:29,549 --> 00:22:33,984 segues are segueing now to a navigation controller. And +现在这个 segue 是 navigation controller 了. 425 00:22:33,986 --> 00:22:36,687 so our prepare is not gonna work, +所以 prepare 方法不会有效 426 00:22:36,689 --> 00:22:40,124 cuz this line of code is going to fail. Right, +这句代码代码判断失败了 427 00:22:40,126 --> 00:22:43,394 because the destination view controller is now a navigation +现在这个 destinationViewController 是 navigationController 428 00:22:43,396 --> 00:22:43,594 controller. Of course, +显然， 429 00:22:43,596 --> 00:22:46,063 a navigation controller is not an image view controller. +navigationController 不是 imageViewController 430 00:22:46,065 --> 00:22:48,165 This is the exact same problem we had before. So +这种问题我们之前遇到过 431 00:22:48,167 --> 00:22:51,869 I'm gonna show you now how to use that extensions mechanism +下面我将演示如何使用 extension 来 432 00:22:51,871 --> 00:22:54,805 to fix this. So I'm gonna create an extension. This is +解决这个问题. 先创建一个 extension. 433 00:22:54,807 --> 00:22:59,143 exactly what I did in the slides of UIViewController. +这是给 UIViewController 的 extension. 434 00:23:00,012 --> 00:23:03,481 Okay, and in this extension, like to scroll up a little so +好的，在 extension 中，好像往下滚动一点 435 00:23:03,483 --> 00:23:07,351 you can see it better. Okay, inside this extension, +更方便你们看. 好的，在这个 extension 中， 436 00:23:07,353 --> 00:23:11,689 I'm gonna add the var contentViewController. +我准备添加一个 contentViewController 变量. 437 00:23:11,691 --> 00:23:14,525 Which is a UIViewController, okay? +类型是 UIViewController 438 00:23:14,527 --> 00:23:17,862 I'm adding this var to the class UIViewController. +这是给 UIViewController 添加的变量 439 00:23:17,864 --> 00:23:21,232 So, all UIViewControllers will now respond to this property +所以所有的 UIViewController 都有一个叫做 440 00:23:21,234 --> 00:23:24,568 contentViewController. Okay? It's gonna be get only. +contentViewController 的属性了. 将它声明为只读属性. 441 00:23:24,570 --> 00:23:27,171 It's gonna get it. And what I'm gonna put in here is +直接就能获取值. 这里的代码和 442 00:23:27,173 --> 00:23:29,907 basically that same code I had in prepareforSegue, +motion view controller 中的 prepareforSegue 方法 443 00:23:29,909 --> 00:23:32,309 in a motionview controller. I'm gonna say, +代码相同，这样写， 444 00:23:32,311 --> 00:23:37,915 if I can let navcon = self as a UINavigationController, +if let navcon = self as? UINavigationController， 445 00:23:37,917 --> 00:23:43,120 so in otherwords, if I am a navigation controller, +意思是，如果 self 是 UINaviagtionController， 446 00:23:43,122 --> 00:23:47,858 then return navcon.visibleViewController. +就返回 navcon.visibleViewController. 447 00:23:47,860 --> 00:23:50,594 Okay? The only problem with this is this is +这里唯一的问题就是 448 00:23:50,596 --> 00:23:53,631 an optional view controller, because the navigation +这个 view controller 是可选值，因为 navigation 449 00:23:53,633 --> 00:23:56,700 controller might not have anything showing. Okay, so +controller 可能不会展示任何信息，所以 450 00:23:56,702 --> 00:24:00,237 I need to return something because contentViewController +这里必须要返回一个确切的值，因为 contentViewController 451 00:24:00,239 --> 00:24:02,940 does not return an optional So I'm gonna use this +不是一个可选类型. 所以我准备用 ?? 将默认值 452 00:24:02,942 --> 00:24:06,210 defaulting to say if I have a NavigationController and +设置为 self，如果有 NavigationController 453 00:24:06,212 --> 00:24:08,779 it has no visible ViewController, just return +但是 visibleViewController 为空的话，就返回 454 00:24:08,781 --> 00:24:12,082 self, which is to say the NavigationController itself, +self，也就是 NavigationController 455 00:24:12,084 --> 00:24:14,819 okay? Otherwise, we can just return self. So if it's not +其他情况，就返回 self. 即如果不是 456 00:24:14,821 --> 00:24:17,655 a NavigationController, then the content is myself. +NavigationController，就返回 self 作为 content 457 00:24:17,657 --> 00:24:22,293 Everyone understand that code right there? Okay? Good. +大家对这段代码有疑问吗？没有？好的. 458 00:24:22,295 --> 00:24:25,296 So, now that we have this, we can just use that method right +有了这个以后，我们在这里直接调方法就可以了. 459 00:24:25,298 --> 00:24:29,400 here. Okay? Instead of asking if the destination can view +这里还要把之前判断的 destination view 460 00:24:29,402 --> 00:24:31,535 controller is an image view controller, I'm gonna ask if +controller 是 imageViewController 改为判断 461 00:24:31,537 --> 00:24:36,240 the destination controller's content view controller, and +destination controller 的 content view controller 是否是 462 00:24:36,242 --> 00:24:38,742 I can escape complete, cuz now that's a method on U, I, +imageViewController. 现在这个方法，哦，这个 + 463 00:24:38,744 --> 00:24:41,579 this is a UI view controller. This is a method on UI view +就是 UIViewController 了，这个方法就是 UIViewController 的 464 00:24:41,581 --> 00:24:44,381 controller. I'm just gonna ask if the content view controller +只需要判断 content view controller 是否 465 00:24:44,383 --> 00:24:49,954 is an image view controller. Okay? So now we should be able +是 image view controller 就行了. 现在在 iPad 上跑起来 466 00:24:49,956 --> 00:24:54,825 to run an iPad and get some nice titles. All right. +应该就可以看到标题了. 467 00:24:54,827 --> 00:24:58,162 Cassini again. We've got the navigation controller up here. +依然打开 Cassini，能看到这里有个 navigation controller 468 00:24:58,164 --> 00:25:00,297 There's Cassini. Sure enough, there's the title, right. +这是 Cassini，没问题，这是标题 469 00:25:00,299 --> 00:25:04,568 We set the title right here. Ivc.title = imageName, okay? +我们在这里加上了标题，ivc.title = imageName 470 00:25:04,570 --> 00:25:11,275 And of course, we can zoom around, okay? +当然，我们还可以进行缩放 471 00:25:11,277 --> 00:25:13,310 All right, any questions about that before I go back to +讲到这里，大家有什么问题吗？ 472 00:25:13,312 --> 00:25:18,449 the slides? All right. Let's hit the slides here. +好的，再回到讲义. 473 00:25:23,689 --> 00:25:26,524 Okay, so now we're gonna talk about multithreading, so +接下来，我会讲讲多线程 474 00:25:26,526 --> 00:25:28,592 we can fix that problem where our Cassini app, +这样就能修复 Cassini app 中，当我们加载大图时 475 00:25:28,594 --> 00:25:31,962 when we click on the big image, it just froze. Okay. +导致的界面卡死问题了. 476 00:25:31,964 --> 00:25:36,033 When you build an app, never have it freeze like that ever. +当你做一款 app 时，千万不要出现界面卡死的情况 477 00:25:36,035 --> 00:25:38,435 In fact, if it freezes like that, probably you won't get +事实上，出现界面卡死的情况， 478 00:25:38,437 --> 00:25:41,605 through the app store approval process. Okay. So the only +还会影响你上架 app store. 解决界面卡死的 479 00:25:41,607 --> 00:25:44,808 way to stop it from freezing is to use multithreading. +唯一方式，就是使用多线程. 480 00:25:44,810 --> 00:25:48,646 Okay. So, multithreading just means we're going to +多线程意味着我们会在 481 00:25:48,648 --> 00:25:50,781 have different threads of execution, +不同的线程中执行任务 482 00:25:50,783 --> 00:25:54,118 okay? Different places in, in our iPhone or +在，在 iPhone 或 iPad 的不同的地方 483 00:25:54,120 --> 00:25:56,887 our iPad where code is running, okay? +执行代码 484 00:25:56,889 --> 00:26:00,090 And these, these appear to run simultaneously, but +这些代码，几乎是同时运行的， 485 00:26:00,092 --> 00:26:03,227 it'll even work on a single core processor, okay, +即使在单核处理器上，也没问题 486 00:26:03,229 --> 00:26:07,231 not a multiprocessor. It works, then, by timesharing. +虽然不是多核处理，但是运用了分时操作手段 487 00:26:07,233 --> 00:26:08,399 Okay. And so you got one thing running, +所以，一个事件在执行， 488 00:26:08,401 --> 00:26:09,867 another thing running and it's kinda going back and +然后再切换到另一个事件，执行后又切回刚才的事件 489 00:26:09,869 --> 00:26:13,304 forth. Letting them each run a little bit and maybe if one of +继续执行. 每个事件都能执行一段时间，如果某个事件 490 00:26:13,306 --> 00:26:15,573 them's more important than the other, it gets run a lot and +在其中比较重要，那么就会停留得就一些， 491 00:26:15,575 --> 00:26:18,576 the other one doesn't get to run so much. Okay? But +次要的事件就不会占用那么长事件. 492 00:26:18,578 --> 00:26:21,545 that's basically what multithreading is all about. +这就是多线程最基础的部分. 493 00:26:21,547 --> 00:26:22,079 So how many people have, +在做的有同学已经， 494 00:26:22,081 --> 00:26:25,583 have done any multithreading programming of any kind? Okay, +已经做过多线程的项目了？好吧， 495 00:26:25,585 --> 00:26:28,586 so some of you have, okay. About a little less than half +一部分同学，大概不到一半的人吧。 496 00:26:28,588 --> 00:26:31,722 of you. Okay, good. So in iOS multithreading is about +谈到 iOS 上的多线程，其实都是 497 00:26:31,724 --> 00:26:35,859 queues, okay? Queue meaning like, if you go to the movies +队列. 队列就像是...如果你在 England 去 498 00:26:35,861 --> 00:26:37,895 maybe in England [LAUGH] they would say, well, +看电影，那么他们会说， 499 00:26:37,897 --> 00:26:40,664 get in the queue, meaning the line to get into the movie, +排队去，意思是，排队依次进电影院. 500 00:26:40,666 --> 00:26:43,901 okay? So same thing here, and it's the same thing as queue +这里的队列和计算机科学中队列 501 00:26:43,903 --> 00:26:46,971 in the computer science sense, right? A queue is a thing, +的含义是一样的. 队列其实就是一个东西， 502 00:26:46,973 --> 00:26:48,973 a bunch of things lined up to do something. +一个有先后顺序的东西. 503 00:26:48,975 --> 00:26:54,912 From 044db15d4ebdbf9c45041532cc27d835449083ab Mon Sep 17 00:00:00 2001 From: saitjr Date: Mon, 26 Sep 2016 23:20:09 +0800 Subject: [PATCH 11/23] finish 1-500 in 8. Multithreading and Text Field --- subtitles/8. Multithreading and Text Field.srt | 2 ++ 1 file changed, 2 insertions(+) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index a65d536..4c107a8 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -2511,10 +2511,12 @@ a bunch of things lined up to do something. 503 00:26:48,975 --> 00:26:54,912 All right. And these queues contained an iOS functions. +这些队列包含了 iOS 的方法. 504 00:26:54,914 --> 00:26:58,482 Okay? Most of the time these functions are closures. Okay? +绝大多数方法都是闭包. 好吧？ 505 00:26:58,484 --> 00:27:02,052 From 5285fb35f6f05929b98c7cd30ccb91f9b1a4ba1c Mon Sep 17 00:00:00 2001 From: saitjr Date: Sun, 23 Oct 2016 19:23:50 +0800 Subject: [PATCH 12/23] translate 510~640 --- .../8. Multithreading and Text Field.srt | 191 +++++++++++++++++- 1 file changed, 185 insertions(+), 6 deletions(-) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index 4c107a8..edd6622 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -2521,718 +2521,897 @@ Okay? Most of the time these functions are closures. Okay? 505 00:26:58,484 --> 00:27:02,052 That you've put in there. Okay? Blocks of code that you +然后加入到队列中. 就是闭包中的代码， 506 00:27:02,054 --> 00:27:06,824 put in this queue. Okay? And then, the system simply runs +加入到队列中. 接着，系统会单独运行 507 00:27:06,826 --> 00:27:09,693 along this queue, pulls the next thing off the queue and +这个队列，将队列中的任务取出， 508 00:27:09,695 --> 00:27:13,430 starts it running in a separate thread, okay? +然后在独立的线程中运行. 509 00:27:13,432 --> 00:27:16,100 And you can have multiple of these queues and the system is +你也可以有很多个队列，然后系统便会 510 00:27:16,102 --> 00:27:18,602 pulling them off each one and running them un, in their +分别取出，然后...在各自的线程中 511 00:27:18,604 --> 00:27:21,705 own threads, simple as that, you just got multithreading. +执行，就这么简单的用上了多线程. 512 00:27:21,707 --> 00:27:24,642 Okay. Now there's a little bit of trickiness +那么现在有个问题， 513 00:27:24,644 --> 00:27:25,909 here of what are these queues and +队列是什么， 514 00:27:25,911 --> 00:27:27,444 how do you put things on the queues, but +怎么将任务加入到队列中， 515 00:27:27,446 --> 00:27:30,180 that's the fundamental way these work. Now queues can +这属于队列运行原理. 队列可以是 516 00:27:30,182 --> 00:27:34,118 either be serial, which means the function that's on the top +串行的，意思是只有当上一个任务执行完后， 517 00:27:34,120 --> 00:27:37,154 of the queue gets pulled off, it runs to completion, and +新的队首元素才会出队 518 00:27:37,156 --> 00:27:40,824 then the next one gets pulled off. That's serial queues. Or +接着执行. 这就是串行队列. 519 00:27:40,826 --> 00:27:43,494 they can be concurrent, where the system pulls the top +队列也可以是并行的，意思是系统出队 520 00:27:43,496 --> 00:27:46,130 one off the queue, starts it running in a thread. If it's +一个队首元素，就立即在一个线程中执行. 如果是这样， 521 00:27:46,132 --> 00:27:48,599 got more thread resources, it takes the next one off, +就会占用更多的资源，下一个任务出队以后 522 00:27:48,601 --> 00:27:51,402 starts it running in another thread while the first one's +就会在另一个线程中进行执行，此时，第一个出队的任务 523 00:27:51,404 --> 00:27:51,502 still running, and +仍在执行， 524 00:27:51,504 --> 00:27:55,873 it might keep pulling a whole bunch of them off. Okay, so +这种队列甚至可以直接将整个队列元素出队执行. 525 00:27:55,875 --> 00:27:57,775 that's a concurrent queue. +这就是并行队列. 526 00:27:57,777 --> 00:28:00,544 All right, so let's talk about the queues, how we get them, +接下来，再来看看队列的其他知识. 我们怎么获得队列， 527 00:28:00,546 --> 00:28:03,781 what, what we call them, etc. The most important queue, +怎样调用它们，等等. 对重要的队列， 528 00:28:03,783 --> 00:28:06,717 it's a serial queue called the main queue, okay? +就是一个称为主队列的串行队列. 529 00:28:06,719 --> 00:28:10,554 The main queue is where all UI activity has to happen. And +主队列是刷新 UI 控件的队列. 530 00:28:10,556 --> 00:28:14,658 this is super important for you to understand. That if you +大家一定要着重理解这个知识点. 如果你在 531 00:28:14,660 --> 00:28:19,063 want to do anything where you call something a UI kit, okay, +做一些和 UIKit 相关的动作，比如 532 00:28:19,065 --> 00:28:21,331 UI button, UI anything, all right, +UIButton，或其他 UI 元素， 533 00:28:21,333 --> 00:28:24,334 with a couple of exceptions which I'll talk about later. +包括之后我们还会学到的其他 UI 控件. 534 00:28:24,336 --> 00:28:27,104 You need to be making those calls on the main queue. +它们都必须要在主队列中进行操作. 535 00:28:27,106 --> 00:28:31,241 In other words, you can't put those calls in a closure that +换句话说，它们不能再其他队列的闭包 536 00:28:31,243 --> 00:28:34,378 you put on some other queue. Okay, it has to be on the main +中执行. 必须在主队列中执行》 537 00:28:34,380 --> 00:28:39,149 queue, all right? Now conversely, all non-UI +记住了吗？相反，所有和 UI 控件 538 00:28:39,151 --> 00:28:42,519 activity that's gonna take any amount of time or resources, +无关的操作，可能会耗时，或耗资源的操作， 539 00:28:42,521 --> 00:28:45,589 probably wants to be off the main queue. So it never blocks +就不要放到主队列中. 千万不要阻塞 540 00:28:45,591 --> 00:28:48,092 the main queue. We want the main queue reserved for +主队列. 我们应该尽可能的将主队列的资源 541 00:28:48,094 --> 00:28:51,562 doing our UI stuff as much as possible. Okay, now this is +用来调度 UI 元素. 当然，希望 UI 控件能及时响应 542 00:28:51,564 --> 00:28:55,799 not only cuz we want our main queue UI to be responsive, +只是其中一个原因， 543 00:28:55,801 --> 00:28:56,767 okay, that's the main reason, but +也是最主要的原因，另外 544 00:28:56,769 --> 00:29:00,671 also it serializes the activity on the main queue so +一个原因，是因为主队列是串行队列，所以 545 00:29:00,673 --> 00:29:03,907 that our UI is presented in an orderly fashion. If, +UI 元素能按照我们给的顺序来执行. 如果， 546 00:29:03,909 --> 00:29:06,343 if we allowed our UI to be on all these different queues, it +如果允许在不同的队列中操作 UI，实际上却是是 547 00:29:06,345 --> 00:29:08,912 could, things would be drawing at all different rates and +可以的，但是绘制速度就会不同，从而出现 548 00:29:08,914 --> 00:29:09,480 overlapping, it would be +重叠，预测不了 549 00:29:09,482 --> 00:29:11,882 unpredictable as to what happened on screen. Okay, so +界面效果. 所以 550 00:29:11,884 --> 00:29:15,285 we use the main queue as kind of a synchronization point +我们需要要利用主队列的同步性， 551 00:29:15,287 --> 00:29:18,522 where everybody comes back to draw on the main queue, +保证所有的绘制都在主队列中进行， 552 00:29:18,524 --> 00:29:22,259 all right? Now the main queue can only pull a closure or +明白了吗？主队列每次会出队一个闭包或 553 00:29:22,261 --> 00:29:24,294 a function off of the main queue and +一个方法， 554 00:29:24,296 --> 00:29:26,630 work on it when it's quiet. In other words, +在静默时，执行它. 换句话说， 555 00:29:26,632 --> 00:29:28,532 it's not off doing something else, like drawing or +它一直都是执行状态，比如在绘制，或 556 00:29:28,534 --> 00:29:31,835 something like, like that. Now the system is using the main +在执行和绘制差不多的任务. 主队列会一直在 557 00:29:31,837 --> 00:29:33,403 queue behind the scenes all the time. +系统后台运行着. 558 00:29:33,405 --> 00:29:35,572 For example, you know about draw req. Right. +比如，你知道绘制操作吧. 559 00:29:35,574 --> 00:29:38,342 I told you draw req gets called by the system and +我之前说过，绘制是系统在调用， 560 00:29:38,344 --> 00:29:40,277 it doesn't get called, you don't call it, +你并没有手动去调用， 561 00:29:40,279 --> 00:29:42,913 you don't tell it to, you just set needs display. +并没有让系统去调，只是告诉系统它需要显示. 562 00:29:42,915 --> 00:29:44,348 Well, you set needs display and +设置在主线程空闲的时候 563 00:29:44,350 --> 00:29:48,585 as soon as the main queue gets quiet, it goes and runs some +进行显示，系统会运行或调用某些 564 00:29:48,587 --> 00:29:51,555 function that causes that draw req to be called. So +方法来进行绘制. 这便是 565 00:29:51,557 --> 00:29:54,525 you see how that works, okay? So that's what's going on in +绘制的工作原理. 这便是主队列 566 00:29:54,527 --> 00:29:57,294 the main queue. What about other queues? Okay, so +在处理的东西. 那么其他队列呢？看 567 00:29:57,296 --> 00:30:00,030 there's, I'm, in the next slide I'm gonna talk about +这里，下个话题便会讲讲 568 00:30:00,032 --> 00:30:02,800 two different kinds of other queues that you can use to run +其他两种不同的队列，能用来处理 569 00:30:02,802 --> 00:30:06,236 all your non-UI stuff. All right? So the first, +所有和 UI 无关的队列. 目前， 570 00:30:06,238 --> 00:30:09,039 not gonna talk about this now, that'll be on the next slide. +我们暂时不谈这个，这是下个话题. 571 00:30:09,041 --> 00:30:12,142 So on this slide I'm gonna talk a little bit about how we +这张幻灯片还有一点东西没讲完，关于如何 572 00:30:12,144 --> 00:30:14,845 put something on a queue and the main way we do it is +将任务放到队列中，最常见的做法是 573 00:30:14,847 --> 00:30:17,981 -with this function right here called dispatc_async. +with this function right here called dispatch_async. +调用一个叫 dispatch_async 的方法. 574 00:30:17,983 --> 00:30:22,986 -Dispatc_async takes two arguments. One is the queue to +Dispatch_async takes two arguments. One is the queue to +Dispatch_async 有两个参数. 一个是要加入的 575 00:30:22,988 --> 00:30:25,455 put it on, like the main queue or one of these other queues, +队列，可以是主队列，或者其他队列， 576 00:30:25,457 --> 00:30:29,760 and the second argument is the function to put on the queue, +第二个参数是，要加入队列的方法， 577 00:30:29,762 --> 00:30:32,963 again, usually it's a closure. You see how I'm using trailing +当然，通常是闭包. 我这里简单写了一个 578 00:30:32,965 --> 00:30:35,933 closure syntax right there? Okay. This is two arguments. +闭包的语法. 这有两个参数， 579 00:30:35,935 --> 00:30:39,002 One argument. Two arguments. So this is the closure you're +一个参数. 两个参数. 这就是加入到队列中的 580 00:30:39,004 --> 00:30:41,605 gonna put on there. What's cool about these closures, +闭包. 看起来很不错吧， 581 00:30:41,607 --> 00:30:43,607 they take no arguments and then return no arguments. +闭包没有参数，也没有返回值. 582 00:30:43,609 --> 00:30:46,910 So they're really easy to, to [LAUGH] put into your code. +所以，非常容易嵌到你的代码中（笑~ 583 00:30:46,912 --> 00:30:50,180 Okay? And you can put anything you want in here. Okay? +你可以将任何想执行的代码扔到里面. 584 00:30:50,182 --> 00:30:53,884 But if this gonna do UI, you better not put it on anything +当然，最好是将 UI 操作扔进去，而不是别的操作， 585 00:30:53,886 --> 00:30:58,388 but the main queue. All right, so how do you get the queue? +毕竟这是主线程. 所以，怎样获得一个队列呢？ 586 00:30:58,390 --> 00:30:59,823 How do you get this little queue argument? +怎样传入这个队列参数？ 587 00:30:59,825 --> 00:31:02,993 Well, for the main queue, you call this function, +对于主队列来说，可以通过调用 588 00:31:02,995 --> 00:31:05,963 -dispatc_ge_mai_queue. Now, you might ask, +dispatch_get_main_queue. Now, you might ask, +dispatch_get_main_queue 来获得. 你或许会问， 589 00:31:05,965 --> 00:31:10,100 why is all these underbars and why does this look like this? +为什么这么多下划线，为什么这个方法长这样？ 590 00:31:10,102 --> 00:31:15,339 This is basically a CAPI, okay, from iOS before Swift, +因为这是基于 CAPI 的，属于 iOS，而不是 Swift 的语法， 591 00:31:15,341 --> 00:31:18,008 and so it comes into swift looking like a CAPI. +所以这使得 Swift 看起来像 CAPI 一样. 592 00:31:18,010 --> 00:31:21,011 These are Swift, these are just Swift global functions. +在 Swift 中，这是个全局方法. 593 00:31:21,013 --> 00:31:23,413 But the reason this is not object oriented, for +它不是面向对象的，因为 594 00:31:23,415 --> 00:31:26,083 example is because this is a CAPI. +它是 CAPI. 595 00:31:26,085 --> 00:31:28,852 This, this is called grand central dispatch actually, +实际上，它被称为 GCD（大中枢派发） 596 00:31:28,854 --> 00:31:30,454 that's why they all start with dispatch, +所以这个方法以 dispatch 开头， 597 00:31:30,456 --> 00:31:33,290 all this multithreading stuff, and that's why it looks like +这就是为什么，所有这类多线程接口，都和这个类似. 598 00:31:33,292 --> 00:31:37,094 this. I'm gonna show you the object-oriented way to do +之后我会介绍怎么用面向对象的方式使用 599 00:31:37,096 --> 00:31:40,764 this in a minute, but actually we're gonna end up using these +这些接口，在此之前，你还会继续 600 00:31:40,766 --> 00:31:44,768 C-like ones more often, all right? So, again, all UI stuff +使用 C 语言的风格的接口. 再次强调，所有 UI 的操作 601 00:31:44,770 --> 00:31:49,039 have to be on this main queue. It's a serial queue, okay, so +都必须在主队列中进行. 这是个串行队列， 602 00:31:49,041 --> 00:31:51,608 nothing happens concurrently on this queue, +所以这个队列中不可能有并行的操作出现， 603 00:31:51,610 --> 00:31:55,112 things happen in order in the order they go in, okay? +入队是什么顺序，出队就是什么顺序，有问题吗？ 604 00:31:55,114 --> 00:31:57,381 And, but all time-consuming stuff, +所有耗时的操作， 605 00:31:57,383 --> 00:31:59,750 okay, or even worse stuff that might block, +或其他耗资源的操作，都可能造成阻塞， 606 00:31:59,752 --> 00:32:02,786 like you're going out to the network to get an image, +就像网络请求图片这类的操作， 607 00:32:02,788 --> 00:32:05,555 like we are doing where that block's waiting for +或者其他因等待网络响应， 608 00:32:05,557 --> 00:32:07,958 the Web server on the other side to respond, +而导致阻塞的操作， 609 00:32:07,960 --> 00:32:10,794 all that wants to happen off the main queue. +这些操作，都不应该出现在主队列中. 610 00:32:10,796 --> 00:32:15,032 -Now you still dispatch to that queue using dispatc_async. +Now you still dispatch to that queue using dispatch_async. +目前我们在使用 dispatch_async 来派发队列. 611 00:32:15,034 --> 00:32:17,367 You go down here and you say look at the bottom, +看到讲义的底部， 612 00:32:17,369 --> 00:32:20,170 it says dispatc_async, not the main queue in here. +参数这里写到，不一定非要传入主队列. 613 00:32:20,172 --> 00:32:22,973 And I'll talk about where you get that queue in a second. +之后会讲到如何获得其他队列. 614 00:32:22,975 --> 00:32:24,007 And then open curly brace, +接着，代码包含在大括号中， 615 00:32:24,009 --> 00:32:27,644 so this is a closure, inside that closure you do the non-UI +所以这是一个闭包，在闭包中，执行的是和 UI 无关的 616 00:32:27,646 --> 00:32:31,081 thing that takes a long time or blocks. And then still +操作，它可能会花很长时间，或者发生阻塞. 接着又是一个 617 00:32:31,083 --> 00:32:35,485 -inside this closure, you dispatc_async again. This +inside this closure, you dispatch_async again. This +闭包，再次 dispatch_async. 这次 618 00:32:35,487 --> 00:32:39,990 time back to the main queue to do the UI stuff that you need, +回到了主队列中，处理和 UI 相关的操作， 619 00:32:39,992 --> 00:32:43,160 maybe that the image you got from doing this, you now put +可能是你请求完了图片，需要 620 00:32:43,162 --> 00:32:47,064 this in the UI here. So look how I'm dispatching within +扔到 UI 上进行显示. 所以来看看如何通过闭包 621 00:32:47,066 --> 00:32:50,567 a closure. So can you imagine this outer closure +来派发它们. 你能想象外部闭包 622 00:32:50,569 --> 00:32:53,770 is off running on some other thread in some other queue and +在其他队列的其他线程上运行， 623 00:32:53,772 --> 00:32:57,908 in the middle of it, it puts a block of code, +然后在其中，又有一个代码块， 624 00:32:57,910 --> 00:32:58,508 this block right here, +就是这个代码块， 625 00:32:58,510 --> 00:33:02,279 this closure. It puts it back on the main queue, this one +这个闭包. 又回到了主队列， 626 00:33:02,281 --> 00:33:05,315 continues to run after that in fact dispatc_async, +继续通过 dispatch_async 方法执行操作， 627 00:33:05,317 --> 00:33:08,418 that function always returns immediately. Because all it +这个方法会立即返回. 因为它是将任务 628 00:33:08,420 --> 00:33:11,655 does is put things on queues, it doesn't actually execute +扔到队列中，而没有真正执行 629 00:33:11,657 --> 00:33:13,490 any of the code inside the block. +代码块中的代码. 630 00:33:13,492 --> 00:33:16,827 It just puts that block of code onto the queue. Okay, and +只是将代码块扔到了队列中. 631 00:33:16,829 --> 00:33:20,397 then this outer closure just happily runs to completion and +接着，这个外部闭包就 632 00:33:20,399 --> 00:33:23,500 it's done. Meanwhile, that inner block has been posted +执行完了. 与此同时，内部闭包也扔到了 633 00:33:23,502 --> 00:33:24,868 on the main queue and it's just waiting for +主队列中，等待 634 00:33:24,870 --> 00:33:27,637 the main queue, for it to be first in line and +主队列执行. 排到主队列中， 635 00:33:27,639 --> 00:33:28,405 for the main queue to be quiet, and +当主队列空闲下来， 636 00:33:28,407 --> 00:33:33,143 then it'll pick it up and run it. You got it? So this is why +便会出队并执行. 这就是为什么 637 00:33:33,145 --> 00:33:36,680 we use the C function notation because it reads really cool, +我们会用 C 函数，因为看起来真的挺酷的. 638 00:33:36,682 --> 00:33:39,816 okay? Dispatch off the queue this, then dispatch the main +先派发这个队列，然后派发 639 00:33:39,818 --> 00:33:44,087 queue this, okay? It reads very clearly to the person +主队列. 很容易让阅读代码的人 640 00:33:44,089 --> 00:33:46,790 who's reading your code what you intend. Okay, but +明白你的意图. 但是 641 00:33:46,792 --> 00:33:49,192 you do have to remember that this is async, +注意这些都是异步的， 642 00:33:49,194 --> 00:33:53,163 it's out of sync. Just because you say to execute this code, +不是同步的. 因为我们并不需要显性调用这些代码， 643 00:33:53,165 --> 00:33:53,997 it's not gonna happen right away. +这些代码不会立刻执行. 644 00:33:53,999 --> 00:33:56,099 It's just being put on that queue, it'll happen sometime +只是将它们加入到队列中，它们会在 645 00:33:56,101 --> 00:34:00,037 in the future when that queue is ready, okay? When it rises +队列空闲下来的时候自己执行. 当它们是队列 646 00:34:00,039 --> 00:34:04,975 to the top of that queue and the main queue is quiet, okay? +的队首元素，并且主队列闲下来的时候，就会执行. 647 00:34:04,977 --> 00:34:08,111 So how do we get these not the main queue queues? +那么，怎么获得除了主队列以外的队列呢？ 648 00:34:08,113 --> 00:34:10,313 Okay, that we want to run something else on. +比如我们想要执行其他的一些操作. 649 00:34:10,315 --> 00:34:11,415 Well there's really two ways to do it. +这有两种方式可用. 650 00:34:11,417 --> 00:34:15,552 The most common way is to use one of the concurrent queues +最常见的直接使用系统提供的 651 00:34:15,554 --> 00:34:18,121 provided by the system, okay? Now these +并行队列. 这四种队列 652 00:34:18,123 --> 00:34:21,758 queues provided by the system there's four of them, okay? +就是系统提供的. 653 00:34:21,760 --> 00:34:25,295 They each have what's called a quality of service and +它们有着不同的优先级的服务， 654 00:34:25,297 --> 00:34:28,165 the quality of service is really how +服务的优先级其实就是 655 00:34:28,167 --> 00:34:31,668 much attention the system gives to them. +系统会给予多少的关注度. 656 00:34:31,670 --> 00:34:34,304 You can think of it as their priority. High-priority queues +你可以顺着优先级来认识它们. 高优先级队列 657 00:34:34,306 --> 00:34:37,174 get a high quality of service. They get serviced a lot, okay? +拥有最高优先级的服务. 它们能获得较多的服务. 658 00:34:37,176 --> 00:34:41,111 But it's not purely that, but it's generally that. So +但也不是绝对的，只是大致上来说而已. 659 00:34:41,113 --> 00:34:43,513 what are the four qualities of service here? +来看看这四种优先级的服务吧. 660 00:34:43,515 --> 00:34:46,817 -One is USE_INTERACTIVE. So, you can get a queue, you +One is USER_INTERACTIVE. So, you can get a queue, you +一种是 USER_INTERACTIVE. 所以，你可以通过调用 661 00:34:46,819 --> 00:34:49,753 can call this dispatch, get global queue right here. And +get_global_queue 方法来获得一个队列. 662 00:34:49,755 --> 00:34:52,589 you can say give me the user interactive queue. Again, it's +然后给它 USER_INTERACTIVE 优先级. 这是个 663 00:34:52,591 --> 00:34:54,925 a concurrent queue, so it's doing things concurrently, +并行队列，所以会并行处理操作， 664 00:34:54,927 --> 00:34:58,495 it's not serial. And user interactive means +这就不像串行了. USER_INTERACTIVE 意味着 665 00:34:58,497 --> 00:35:01,398 the user just asked to do something. +这是用户要求处理的事情. 666 00:35:01,400 --> 00:35:03,066 It's gonna take a little bit of time, +可能会花一些时间， 667 00:35:03,068 --> 00:35:04,801 so I don't want to do it on the main queue, +虽然我不想再主队列中进行处理， 668 00:35:04,803 --> 00:35:07,604 but I need this done as soon as possible because the user +但是我仍然希望能进行执行，毕竟这是用户 669 00:35:07,606 --> 00:35:09,673 is interacting with me right now, okay? +希望立马响应的操作. 670 00:35:09,675 --> 00:35:11,641 So, this is very high priority, but +所以它拥有最高优先级， 671 00:35:11,643 --> 00:35:15,345 lower priority than the main queue, okay? So, this might be +但这仍然要比主队列的优先级低. 这可能是 672 00:35:15,347 --> 00:35:18,081 something where the user is dragging with their finger, +用户在拖拽手指时， 673 00:35:18,083 --> 00:35:21,218 and you're having to calculate something to make the image +你需要同时计算一些数据并 674 00:35:21,220 --> 00:35:23,220 that's pretty intensive, time wise, and so +立即给出反馈，这时就应该将任务扔到 675 00:35:23,222 --> 00:35:26,089 you put it off on the thread. The user continues to drag, +这种队列中. 用户继续手指继续拖拽， 676 00:35:26,091 --> 00:35:27,390 they're not seeing the result and +但是没有看到数据显示， 677 00:35:27,392 --> 00:35:28,558 then the result comes back in and +等数据计算完成时， 678 00:35:28,560 --> 00:35:30,393 then the user gets to see the result. So +用户才能看到数据. 所以， 679 00:35:30,395 --> 00:35:32,362 the results a little bit behind their finger, +数据会比用户的手势慢一步， 680 00:35:32,364 --> 00:35:33,196 because it takes so much time, but +因为计算会花一些时间， 681 00:35:33,198 --> 00:35:35,799 at least as their finger tracks the main queue is still +但至少主线程一直在监听 682 00:35:35,801 --> 00:35:39,870 listening to their finger, okay, and responding, okay? +手指的轨迹，并且响应还是有的， 683 00:35:39,872 --> 00:35:42,005 So that's what USE_INTERACTIVE is for. +这就是 USER_INTERACTIVE 优先级. 684 00:35:42,007 --> 00:35:45,675 From 1ec32775592faf973e236652908efc0e6c0d37e1 Mon Sep 17 00:00:00 2001 From: Leo Date: Sat, 5 Nov 2016 15:19:45 +0800 Subject: [PATCH 13/23] fix spelling mistake --- ...iple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt b/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt index 19735ae..fec5bc5 100755 --- a/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt +++ b/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt @@ -1288,7 +1288,7 @@ You can move things around wherever you want. Okay, so 323 00:16:03,630 --> 00:16:07,098 -now I have to NVCs in here. One really interesting thing +now I have two MVCs in here. One really interesting thing 324 00:16:07,100 --> 00:16:12,704 From 2217954c236eb496708804d55a3dd10cca75237a Mon Sep 17 00:00:00 2001 From: saitjr Date: Sat, 12 Nov 2016 22:13:06 +0800 Subject: [PATCH 14/23] 700~800 --- .../8. Multithreading and Text Field.srt | 134 +++++++++++++++++- 1 file changed, 129 insertions(+), 5 deletions(-) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index edd6622..d30606b 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -3416,498 +3416,622 @@ So that's what USE_INTERACTIVE is for. 684 00:35:42,007 --> 00:35:45,675 USE_INITIATED means the user just asked me to do this, but +USE_INITIATED 意思是，用户让我处理这个，但是不需要在 685 00:35:45,677 --> 00:35:48,812 it's not in the middle of an interactive event so, you can +用户交互的时候去处理，所以允许事件 686 00:35:48,814 --> 00:35:51,181 take a little bit of time but get back to me right away, +等待一些事件，但一旦处理完一定要有反馈 687 00:35:51,183 --> 00:35:53,950 cuz the user just asked for this, right now, okay? +因为这是用户要求处理的 688 00:35:53,952 --> 00:35:58,255 So, that's lower priority, than an interactive thing. +所以，它的优先级要比交互事件低一等 689 00:35:58,257 --> 00:36:02,626 UTILITY is something that usually runs in the background +UTILITY 一般用于在后台处理 690 00:36:02,628 --> 00:36:06,796 for a long time, okay? Maybe it's fetching data. +一些耗时操作，比如获取数据什么的. 691 00:36:06,798 --> 00:36:09,633 It's cleaning up some database somewhere. It's doing +也可以用于清理数据库，或者 692 00:36:09,635 --> 00:36:12,569 something that the user didn't ask to do, but that needs to +处理一些程序必须要处理， 693 00:36:12,571 --> 00:36:15,305 be done for this program. It's that kind of thing. And +而用户又没有要求处理的事件. 大致就是这一类事件. 694 00:36:15,307 --> 00:36:17,941 then BACKGROUND is even lower priority. This is the kind of +BACKGROUND 的优先级最低. 一般将一些可 695 00:36:17,943 --> 00:36:22,078 thing well it could run today or tomorrow. But you know, +今天，可明天处理的事件加到里面. 也就是， 696 00:36:22,080 --> 00:36:24,247 it's really not something that I need done right away, +没必要立马处理， 697 00:36:24,249 --> 00:36:26,516 I don't really care. So, it's kind of just a, +不需要过于关注的事件. 就好比是， 698 00:36:26,518 --> 00:36:28,318 something that runs along in the background. +在后台默默执行的事件. 699 00:36:28,320 --> 00:36:30,253 It's only gonna happen when things are really quiet, +在没有其他事件需要占用资源的时候， 700 00:36:30,255 --> 00:36:34,991 when nobody wants any other service, okay? So, you get one +它才执行. 到此，你就已经学习了 701 00:36:34,993 --> 00:36:37,594 -of these four queues by saying dispatc_ge_globa_queue, +of these four queues by saying dispatch_get_global_queue, +dispatch_get_global_queue 包含的四种优先级. 702 00:36:37,596 --> 00:36:40,430 you specify which one you want. Then this has this +可根据需要选择. 除此之外， 703 00:36:40,432 --> 00:36:44,768 extra argument ,0 which is reserved for future use, so +还有一个参数 0，这将在之后用到， 704 00:36:44,770 --> 00:36:45,602 you just always put ,0 there. +现在就简单的传 0 就可以了. 705 00:36:45,604 --> 00:36:48,505 -And that's gonna give you back a queue, a dispatc_queu_t +And that's gonna give you back a queue, a dispatch_queue_t +这样函数就会返回 dispatch_queue_t 类型的队列， 706 00:36:48,507 --> 00:36:51,942 that you can then use as your first argument to dispatch +它可以作为 dispatch_async 的第一个参数. 707 00:36:51,944 --> 00:36:55,645 async, okay. So these are the, this is the cues, +那么，这就是， 708 00:36:55,647 --> 00:36:57,514 these are the cues you're most often going to +这就是在你要处理后台事件时， 709 00:36:57,516 --> 00:37:00,383 put this work that needs to be done in the background onto. +最为常用的队列了. 710 00:37:00,385 --> 00:37:03,720 Now, its also possible for you to create your own +当然，你也可以创建自己的 711 00:37:03,722 --> 00:37:07,023 -serial queue. You call dispatc_queu_create. +serial queue. You call dispatch_queue_create. +串行队列. 通过调用 dispatch_queue_create 函数， 712 00:37:07,025 --> 00:37:09,626 You give it a name. This can be any name you want, okay? +并给队列一个名字，任何名字都可以， 713 00:37:09,628 --> 00:37:12,028 This is usually just so you can see it in the debugger, +这在调试的时候经常看到， 714 00:37:12,030 --> 00:37:14,297 okay, this name is gonna appear in the debugger. +队列名称会出现在调试界面中. 715 00:37:14,299 --> 00:37:16,366 -And then you say DISPATC_QUEU_SERIAL, +And then you say DISPATC_QUEUE_SERIAL, +第二个参数是 DISPATC_QUEUE_SERIAL， 716 00:37:16,368 --> 00:37:17,500 saying you want a serial queue. +表示你需要创建串行队列. 717 00:37:17,502 --> 00:37:20,737 Now you will get a serial queue of your own. +这样就能获得一个自己的串行队列了. 718 00:37:20,739 --> 00:37:22,672 And it's gonna be a pretty high priority queue, +这是一个优先级相当高的队列， 719 00:37:22,674 --> 00:37:25,742 nothing like the main queue, but pretty high priority. +虽然不像主队列那么高，但也算是万人之上了. 720 00:37:25,744 --> 00:37:27,644 Why would you ever want a serial queue? +什么时候需要创建串行队列呢？ 721 00:37:27,646 --> 00:37:31,581 Let's say you had a big table that you wanna download +假设你有一个长长的列表，想要下载 722 00:37:31,583 --> 00:37:34,351 a thousand images to put in that table. +一千张图片扔到列表中 723 00:37:34,353 --> 00:37:37,754 Small little images, okay? Well you could do it on +都是些小图标. 你可以 724 00:37:37,756 --> 00:37:40,290 one of these user initiated queues or something like that. +在 USER_INITIATED 队列中或者其他队列中下载. 725 00:37:40,292 --> 00:37:42,225 But it's gonna fork off a whole bunch of threads and +但是这样系统就会创建一大串线程， 726 00:37:42,227 --> 00:37:45,128 try to download as many as it can concurrently. +而且尽可能多的进行并发下载. 727 00:37:45,130 --> 00:37:46,663 Open a whole bunch of network connections. +同时发起一堆网络请求. 728 00:37:46,665 --> 00:37:50,800 Whereas if you do is serially it will do it one by one, +但如果你在串行队列中处理，就会一个一个按秩序下载， 729 00:37:50,802 --> 00:37:53,837 okay? So it kind of throttles, it's a throttling, +就像是限流的阀门， 730 00:37:53,839 --> 00:37:55,872 a way of throttling your access to the network, +有限制的去访问网络. 731 00:37:55,874 --> 00:37:59,109 all right? You usually don't need this. +不过通常不需要这个. 732 00:37:59,111 --> 00:38:02,212 These are usually what you're gonna use for that not main +这些通常会在其他队列中处理，而不是主队列. 733 00:38:02,214 --> 00:38:06,449 queue queue, okay? Now, we're only seeing the absolute +到此，你已学习了多线程必备的一些知识， 734 00:38:06,451 --> 00:38:09,219 tip of the iceberg on multithreading here, +当然这只是冰山一角. 735 00:38:09,221 --> 00:38:13,323 okay? There's a lot more to GCD, Grand Central Dispatch. +更多关于 GCD，Grand Central Dispatch 的内容， 736 00:38:13,325 --> 00:38:14,557 You can look in the documentation for +可以查看文档， 737 00:38:14,559 --> 00:38:16,660 all the functions that start with dispatch underbar and +所有方法都以 dispatch_ 开头， 738 00:38:16,662 --> 00:38:20,263 you'll get an idea, there's at least a couple dozen in there. +至少有一打这样的方法. 739 00:38:20,265 --> 00:38:24,034 I don't have time to cover it in this class. +我没办法在课堂上依次为大家介绍. 740 00:38:24,036 --> 00:38:24,100 You won't need it, +其他方法你也不需要， 741 00:38:24,102 --> 00:38:26,102 you won't need anything more than I just showed you for +除了我介绍给大家的这些方法外，你暂时还用不到别的 742 00:38:26,104 --> 00:38:28,371 the work that you're gonna be doing in your assignments. +包括课后作业也不会用到. 743 00:38:28,373 --> 00:38:31,007 In your final project, you probably also won't need +甚至是最终考核项目，你都可能用不上 744 00:38:31,009 --> 00:38:33,910 anymore than that, but at least you know where to look, +别的方法，但至少要知道用的时候， 745 00:38:33,912 --> 00:38:38,214 if you might need more. There is an object-oriented +能在哪里查到. 这是面向对象的 746 00:38:38,216 --> 00:38:40,850 way of doing all this called, there's two classes, +调用方式，提供了两个类， 747 00:38:40,852 --> 00:38:43,853 NSOperationQueue, which is kind of like dispatch queues. +NSOperationQueue，和 dispatch queue 很像. 748 00:38:43,855 --> 00:38:47,824 And NSOperation, which is kinda like those closures, +还有 NSOperation，和闭包类似， 749 00:38:47,826 --> 00:38:52,929 right, those little functions. Why would you ever want this? +包含要处理的事件. 为什么我们需要这个两个类呢？ 750 00:38:52,931 --> 00:38:56,132 These do have a little bit of extra functionality, +因为它们在 GCD 基础上， 751 00:38:56,134 --> 00:38:59,069 that they wrap from GCD, things like, hey, +还提供了一些额外的功能，比如， 752 00:38:59,071 --> 00:39:00,704 I have these two operations and +两个事件(operation)， 753 00:39:00,706 --> 00:39:04,441 this one depends on this one finishing, okay. And so +一个要在另一个结束之后发起. 754 00:39:04,443 --> 00:39:06,076 I'm gonna put them in a concurrent queue, but +把它们扔在并发队列中， 755 00:39:06,078 --> 00:39:08,845 don't let this other one go until the first one finishes, +也能保证一个在另一个结束之后发起. 756 00:39:08,847 --> 00:39:11,047 right. So dependencies, you can have dependencies and +这就是依赖，你能对事件添加依赖. 757 00:39:11,049 --> 00:39:14,417 things like that. We're not gonna talk about that. +课堂上不讲， 758 00:39:14,419 --> 00:39:16,553 You can look at the documentation if you want. +你可以在文档中看到. 759 00:39:16,555 --> 00:39:20,690 You can do, I think almost everything here with GCD. +我们需要的处理，GCD 已经足够了. 760 00:39:20,692 --> 00:39:23,259 This would be more if you actually are building +如果你是在创建一个 761 00:39:23,261 --> 00:39:26,029 something where there's queue are doing queues and +有很多队列，而且 762 00:39:26,031 --> 00:39:29,299 these operations are doing the actual calculation. Like as +operation 都在处理相关运算. 就像 763 00:39:29,301 --> 00:39:31,568 your model is doing, you're doing some scientific app and +建模一样，做一个科学相关的 app， 764 00:39:31,570 --> 00:39:33,803 it's actually doing all this complex calculation where +并且在处理一些非常复杂的计算， 765 00:39:33,805 --> 00:39:35,372 things depend on each other and all that stuff. +每个计算都相互依赖. 766 00:39:35,374 --> 00:39:38,441 And so it has a lot of queues and a lot of operations going. +这样，就需要很多队列和操作了. 767 00:39:38,443 --> 00:39:40,910 You wouldn't use it as much for things like, I'm fetching +也就这个时候，你需要使用到依赖，如果只是 768 00:39:40,912 --> 00:39:42,879 something from the network and I need to put it in the UI, +需要从网络上拉取数据，然后在 UI 上展示， 769 00:39:42,881 --> 00:39:45,181 and I want that fetched to happen in another queue. +即使想要在其他队列中发起请求， 770 00:39:45,183 --> 00:39:47,317 That kind of stuff you're just going to use the dispatch +dispatch_ 相关方法已经够用了. 771 00:39:47,319 --> 00:39:53,156 underbar, okay. Now, in addition to dispatch underbar, +作为 dispatch_ 的补充， 772 00:39:53,158 --> 00:39:55,625 you have to understand multithreading from +你还需要从 iOS 的 API 中 773 00:39:55,627 --> 00:39:57,827 the perspective of how iOS's API uses it. +理解多线程该如何使用. 774 00:39:57,829 --> 00:40:00,997 Because there are plenty of methods all throughout +因为关于异步线程的方法， 775 00:40:00,999 --> 00:40:05,168 iOS that do what they do asynchronously, using threads. +实在是太多了. 776 00:40:05,170 --> 00:40:08,438 Okay? And the way you see this in the API, is that one of +你在看 API 的时候，其中一个 777 00:40:08,440 --> 00:40:11,941 the arguments to these methods is a block, is a closure, +参数是 block，一个闭包， 778 00:40:11,943 --> 00:40:14,477 right? It's gonna be a closure you provide, and +闭包内容由你提供， 779 00:40:14,479 --> 00:40:16,980 the documentation for that function will say your +文档的解释是，你的闭包 780 00:40:16,982 --> 00:40:21,084 closure's executed off the main cue, asynchronously. +会异步的在主队中执行. 781 00:40:21,086 --> 00:40:23,753 So what kind of methods are we talking about here that do +这就是能解决我们之前问题的方法. 782 00:40:23,755 --> 00:40:27,690 that? Here's one that goes and fetches a URL. Okay, +可以用它来拉取网络数据. 783 00:40:27,692 --> 00:40:30,794 from the internet. Downloads it from the internet. And +进行网络数据下载. 784 00:40:30,796 --> 00:40:32,595 when it, and it does it asynchronously obviously. +它会在异步中处理. 785 00:40:32,597 --> 00:40:34,798 You wouldn't wanna block the main queue waiting for +你也不想要它因为加载 url，而阻塞主队列吧. 786 00:40:34,800 --> 00:40:37,233 this URL to load. And when it comes back, +在响应回来后， 787 00:40:37,235 --> 00:40:39,936 it calls this closure right here, okay? Now +它救护调用这个闭包. 788 00:40:39,938 --> 00:40:44,040 inside this closure, you might want to do some UI things. +在这个闭包中，你就可以做一些 UI 操作了. 789 00:40:44,042 --> 00:40:46,543 Like maybe you downloaded an image and you wanna put it. +比如显示刚下载完成的图片. 790 00:40:46,545 --> 00:40:49,078 But you can't put that code right inside here. +但是你不能直接将 UI 代码写在这， 791 00:40:49,080 --> 00:40:52,015 Because this closure is executed on a different +因为这个闭包会在 792 00:40:52,017 --> 00:40:54,818 thread and on a different queue than the main queue. So +另一个队列的线程中执行，而不是在主队列中执行. 所以 793 00:40:54,820 --> 00:40:56,886 what you would have to do in here is the same thing +这里你还需要 794 00:40:56,888 --> 00:40:57,720 -you have to do with the dispatc_async, +you have to do with the dispatch_async, +像之前创建 dispatch_async 一样， 795 00:40:57,722 --> 00:41:03,560 which is you have to wrap dispatc_async ge_mai_queue +用一个主队列的异步线程去包裹它. 796 00:41:03,562 --> 00:41:07,464 around it, okay? So here's the method. This is an iOS method +就像这样写. 这是个 iOS 的 797 00:41:07,466 --> 00:41:10,333 downloadTaskWithRequest. It takes this last argument, +downloadTaskWithRequest 方法. 最后一个参数， 798 00:41:10,335 --> 00:41:12,836 which is a closure. And inside there you're gonna have to +是一个闭包. 在闭包中， 799 00:41:12,838 --> 00:41:15,572 do this dispatch to the main queue. Because if you wanna do +你需要回到主队列. 因为你要处理 800 00:41:15,574 --> 00:41:18,107 something to the UI, because this is not happening, +UI 相关操作，就不能直接写， 801 00:41:18,109 --> 00:41:21,911 this closure will not be executed on the main queue. +这个闭包不会在主队列中执行. 802 00:41:22,047 --> 00:41:25,982 Got it? So we will talk a little bit about, you're just +明白吗？所以建议大家 803 00:41:25,984 --> 00:41:29,919 gonna run into occasional iOS APIs that take these closures, +可以查查 iOS API 中，异步操作时， 804 00:41:29,921 --> 00:41:32,455 and they're asynchronous. And you just have to know that if +关于这个闭包的描述. 你需要知道，要处理任何 805 00:41:32,457 --> 00:41:33,957 you wanna do anything in the UI, you're gonna have +与 UI 相关的操作，都必须要 806 00:41:33,959 --> 00:41:38,628 to dispatch async back to the main queue. All right, so +先回到主队列. 行，接下来 807 00:41:38,630 --> 00:41:41,364 let's do a demo of this where let's fix Cassini. +我们来完善 Cassini demo 中的问题. 808 00:41:41,366 --> 00:41:44,934 From fe9d4105a75dd9ffdd94ce322b2cae9ce6dac295 Mon Sep 17 00:00:00 2001 From: ZhangNan_ludan Date: Thu, 24 Nov 2016 20:13:53 +0800 Subject: [PATCH 15/23] =?UTF-8?q?=E7=BF=BB=E8=AF=91=E4=BA=86=E7=AC=AC?= =?UTF-8?q?=E4=BA=94=E9=9B=86500-1000?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...ontroller, Gestures, and Multiple MVCs.srt | 517 +++++++++++++++++- 1 file changed, 504 insertions(+), 13 deletions(-) diff --git a/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt b/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt index 77f78ed..99b803b 100755 --- a/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt +++ b/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt @@ -1997,1014 +1997,1262 @@ that's done with a gesture handler. 500 00:27:44,997 --> 00:27:46,664 So you've got gesture recognizers and +现在，你有一个手势识别器和 501 00:27:46,666 --> 00:27:50,067 gesture handlers, okay? And the handler is called +处理手势事件的方法，这个方法 502 00:27:50,069 --> 00:27:53,370 as the recognizer goes through a basically a state machine +在识别器不断从基础的状态机 503 00:27:53,372 --> 00:27:55,506 of recognizing this gesture. Okay, and - +识别到这个手势时被调用 504 00:27:55,508 --> 00:27:58,142 we'll talk about what that state machine looks like. But +我们稍后会讨论这个状态机 505 00:27:58,144 --> 00:27:58,475 it's called repeatedly, +这个状态会不断重复 506 00:27:58,477 --> 00:28:01,145 the handler's gonna be called repeatedly, as the gesture +所以处理手势事件的方法也会不断被调用 507 00:28:01,147 --> 00:28:03,080 goes through the process of being recognized and +手势不断继续，这个过程不断被识别到 508 00:28:03,082 --> 00:28:06,383 moving and all the things it does. Okay now usually +调用也在继续 509 00:28:06,385 --> 00:28:10,454 the first of these things the creating of a recognizer and +通常我们先创建一个手势识别器 510 00:28:10,456 --> 00:28:10,821 adding it to some +然后将它添加 511 00:28:10,823 --> 00:28:14,191 view is usually done by your controller. Okay. +到 view 上，这通常由控制器完成 512 00:28:14,193 --> 00:28:16,560 It doesn't have to be done by your controller but +但并不是必须由控制器完成 513 00:28:16,562 --> 00:28:20,030 it's a good way for +但由控制器添加更好 514 00:28:20,032 --> 00:28:22,866 its views. Okay the views are the minion of the controller +views 是 controller 的仆从 515 00:28:22,868 --> 00:28:26,603 anyway. So, the controller wants to control its minions. +所以，控制器想控制它的仆从 516 00:28:26,605 --> 00:28:30,541 So, it might usually be the one that wants to +控制器通常 517 00:28:30,543 --> 00:28:32,976 add the gesture recognizer to a view but +给 view 添加手势识别器 518 00:28:32,978 --> 00:28:36,013 some views, the gesture recognition is so +但是，对于一些 view 来说，其手势识别器 519 00:28:36,015 --> 00:28:39,783 fundamental to who they are that they add it themselves. +太过于基础，所以他们自己添加 520 00:28:39,785 --> 00:28:40,084 They add it themselves. +他们为自己添加手势识别器 521 00:28:40,086 --> 00:28:42,653 For example, ScrollView. Okay what would a ScrollView +比如说，ScrollView 如果 ScrollView 没有 522 00:28:42,655 --> 00:28:45,456 be without a pan gesture. Just scrolling up and down it would +拖动手势，只是滚来滚去 523 00:28:45,458 --> 00:28:48,726 be useless it wouldn't even be a ScrollView anymore. +这样的 ScrollView 没有什么用，也不会再被叫做 ScrollView 了 524 00:28:48,728 --> 00:28:52,262 So ScrollView adds a pan gesture recognizer and +所以，ScrollView自己添加了拖动手势和 525 00:28:52,264 --> 00:28:54,131 a pinch gesture recognizer to itself. +捏合手势 526 00:28:54,133 --> 00:28:58,001 Probably in it's initializer. Okay but lot of the times your +可能是内部通过自己的初始化方法添加到 527 00:28:58,003 --> 00:28:59,903 controller that's adding the gesture, +但是，大多数时间都是 controller 添加手势的 528 00:28:59,905 --> 00:29:03,140 again the controller can't do the recognition to gesture +再重复一遍，controller 不能识别到手势 529 00:29:03,142 --> 00:29:05,576 only of you with the gesture recognizer can. But +只有你添加了手势识别器的控件可以 530 00:29:05,578 --> 00:29:08,879 the controller can add that gesture recognizer create and +但是，controller可以添加手势识别器 531 00:29:08,881 --> 00:29:11,582 add the gesture I can add it to one of its views in its +创建和添加手势给 controller 里的一个 view 中 532 00:29:11,584 --> 00:29:17,154 view. Okay, the second thing that handler that handles it. +第二件事是，处理方法来处理手势 533 00:29:17,156 --> 00:29:19,723 Well that could be handled by the controller or +可以使 controller 来处理 534 00:29:19,725 --> 00:29:20,691 it might be handled by the view. +也可以是添加了手势的 view 来处理 535 00:29:20,693 --> 00:29:23,393 It could even be handled by someone else. Would never be - +甚至可以是其他人 536 00:29:23,395 --> 00:29:26,663 handled by your model because UI independent. But it could +但是，永远不要在你的 model 中处理，因为UI分离 537 00:29:26,665 --> 00:29:30,100 be anyone in the controller view camps can handle it. +在 controller 或者 view 阵营中的任何一者可以处理 538 00:29:30,102 --> 00:29:34,872 Generally, kind of, if the things that's the gesture is +通常，如果手势的处理事件是 539 00:29:34,874 --> 00:29:38,509 doing is only modifying how the view displays itself, +怎么修改 view 的展示 540 00:29:38,511 --> 00:29:42,012 like in our Faceview, it was just the scale of the view or +像我们的 FaceView 中 view 的大小 541 00:29:42,014 --> 00:29:44,414 maybe somehow it was change in the color of the view. +或是 view 颜色的变化 542 00:29:44,416 --> 00:29:47,518 Then the view is probably going to handle the gesture. +这是，通常是这个view来处理这个手势 543 00:29:47,520 --> 00:29:49,052 Okay, it's gonna both recognize it +这个view不仅识别手势 544 00:29:49,054 --> 00:29:52,990 with the recognizers and handle it. But if the gesture +而且处理对应的事件，但是如果这个手势 545 00:29:52,992 --> 00:29:56,260 is changing the model, then definitely the controller +改变了 model，这种情况绝对是 546 00:29:56,262 --> 00:29:58,662 would be the handler. Do you see why that is? +controller要成为处理事件的对象，你明白吗？ 547 00:29:58,664 --> 00:30:00,597 Because the view can't see the model, okay, +因为，view 是看不到 model 的 548 00:30:00,599 --> 00:30:03,934 but the controller can. So the controller would set itself +但是 controller 可以， controller会成为 549 00:30:03,936 --> 00:30:07,004 as the recognizer of anything that's gonna affect the model. +任何会影响 model 的识别器 550 00:30:07,006 --> 00:30:11,308 We'll see that in the demo as well. Okay, so how do we +我们会在过会儿的 demo 中讲这一点 551 00:30:11,310 --> 00:30:15,445 add a gesture to UIView? We've decided we want a view, +我们应该如何给 UIView 添加手势呢，在这个例子中 552 00:30:15,447 --> 00:30:18,515 in this case lets say to recognize pan. +我们决定让 view 能识别到拖动手势 553 00:30:18,517 --> 00:30:21,752 Okay a pan is putting your finger down on the screen and +拖动手势就是在屏幕上拖动你的手指 554 00:30:21,754 --> 00:30:23,287 moving it around without lifting it up. +拖动时并不抬起手指 555 00:30:23,289 --> 00:30:26,023 And when you lift it up the pan is over. Kay, +当手指抬起来的时候，拖动手势也就结束了 556 00:30:26,025 --> 00:30:27,157 that's what a pan is basically. +这是拖动手势基本的含义 557 00:30:27,159 --> 00:30:30,160 You're panning your finger around. On the screen. +你可以在屏幕上来回拖动你的手指 558 00:30:30,162 --> 00:30:33,831 All right? So if we wanted to do that. Well, one, so we have +如果我们想添加这样一个手势 559 00:30:33,833 --> 00:30:37,067 to somewhere in our controller code add a pan gesture +我们需要在 controller 的代码中创建一个 pan 手势识别器 560 00:30:37,069 --> 00:30:40,437 recognizer to the view that we want the panning to happen in. +并将它添加到我们想让拖动手势发生的 view 上 561 00:30:40,439 --> 00:30:45,142 Okay? Well a great place to do that is in that didSet, okay? +最好是在 didSet 方法中做这些事情 562 00:30:45,144 --> 00:30:48,111 Of the outlet. Cuz as soon as that view that +因为在获得这个 view 的同时 563 00:30:48,113 --> 00:30:48,145 as soon as we get a pointer to it, let's immediately just add +我们立即为他添加了手势 564 00:30:48,147 --> 00:30:51,381 we want to pan, +我们想要拖动时 565 00:30:51,383 --> 00:30:53,350 the gesture recognizer right there. Okay. +对应的手势识别器已经准备好了 566 00:30:53,352 --> 00:30:55,886 And we know that this didSet right here. +我们知道这里的 didSet 方法 567 00:30:55,888 --> 00:30:58,622 Okay we already saw this in the demo I just did. This +在刚刚的 demo 中我写过这个方法 568 00:30:58,624 --> 00:31:01,758 didSet, when you're doing it to an outlet. This gets called +当你处理一个 outlet 时 569 00:31:01,760 --> 00:31:05,963 only once. It gets called when iOS first hooks up that view. +他在 iOS 绘制这个 view 时刚好调用，且只调用一次 570 00:31:05,965 --> 00:31:10,567 Kay, perfect time to go add a gesture recognizer. Okay, so +这是一个添加手势识别器的完美时机 571 00:31:10,569 --> 00:31:14,938 we're gonna do that. First, we are going to create the pan +我们开始这么做，首先，创建手势识别器 572 00:31:14,940 --> 00:31:18,275 gesture recognizer. Okay, here is a concrete subclass of +PanGestureRecognizer 是 UIGestureRecognizer 的 573 00:31:18,277 --> 00:31:21,478 UIGestureRecognizer called pan gesture recognizer. +一个继承实体类 574 00:31:21,480 --> 00:31:26,617 It takes two arguments here. The first is who is going +他有两个参数 575 00:31:26,619 --> 00:31:31,822 to handle this gesture when I recognize it. Okay. +第一个是当识别到手势后，处理手势的对象 576 00:31:31,824 --> 00:31:33,957 So this gesture pan gesture recognizer saying hey, +当PanGestureRecognizer 577 00:31:33,959 --> 00:31:36,760 if I recognize a pan, who's gonna handle it for me? +识别到拖动手势后，会问谁帮我来处理这个手势呢？ 578 00:31:36,762 --> 00:31:40,764 And the answer is, self, so that's the controller. Okay. +答案是，controller 自己来处理手势 579 00:31:40,766 --> 00:31:42,499 Cuz there's an outlet in the controller so +因为这是在一个 controller 中的 outlet 580 00:31:42,501 --> 00:31:44,968 the target itself means the controller is going to +target 为 self，指这个 controller 自己将会 581 00:31:44,970 --> 00:31:50,007 handle this pan itself. Okay. The second argument here. +处理拖动手势，第二个参数是 582 00:31:50,009 --> 00:31:55,379 Is what method do you want me to invoke in self? +在识别到这个手势后 583 00:31:55,381 --> 00:31:58,749 When this gets recognized, okay? +你想让我调用 self 中的什么方法？ 584 00:31:58,751 --> 00:32:00,984 Now there's some kind of funky syntax here. +第二个参数的语法可能有些难以理解 585 00:32:00,986 --> 00:32:05,989 This has to be an Objective-C runtime compatible selector, +这是一种兼容 OC 运行时的选择器 586 00:32:05,991 --> 00:32:10,093 okay? That just means a selector, a method, okay, +仅仅意味着是一个选择器、一个方法 587 00:32:10,095 --> 00:32:10,928 the name of a method, +方法的名字 588 00:32:10,930 --> 00:32:14,631 that is visible to the Objective-C runtime. Now, for +对于 OC 运行时是可见的 589 00:32:14,633 --> 00:32:17,701 this to be visible to run to the Objective-C runtime, +因为他对于 OC 运行时是可见的 590 00:32:17,703 --> 00:32:21,538 this method must be in a class that inherits from NS object. +所以，这个方法必须出现在某个继承自 NSObject 的类中 591 00:32:21,540 --> 00:32:24,641 Remember I was talking about that NS object thing and +记得我之前说过关于 NSObject 592 00:32:24,643 --> 00:32:25,776 sometimes you're gonna need it, well, +有些时候你需要它 593 00:32:25,778 --> 00:32:28,345 here you would need it. Now you don't usually care about +此时我们就需要，但我们通常不用关心这个问题 594 00:32:28,347 --> 00:32:31,281 that here, because this is almost always being handled by +因为这个处理方法通常在一个 595 00:32:31,283 --> 00:32:34,952 either a UI view controller which definitely inherits from +UIViewController 中， 而这个UIViewController 绝对继承了 596 00:32:34,954 --> 00:32:35,619 NS objects or a UI view, +NSObject 又或者在一个 UIView 中 597 00:32:35,621 --> 00:32:38,322 which definitely inherits from NS object, right? So +UIView 也绝对继承了 NSObject 598 00:32:38,324 --> 00:32:41,692 you usually don't care, okay? You're not usually going to be +所以你通常不用关心这个问题，你不会 599 00:32:41,694 --> 00:32:44,761 trying to send this to some object that's a Swift object +尝试将这个方法给一个没有 600 00:32:44,763 --> 00:32:48,699 that doesn't inherit from NS object. But this syntax here +继承 NSObject 的 Swift 类 601 00:32:48,701 --> 00:32:53,070 means create an Objective-C compatible selector, okay? +这个语法表示创建一个 OC 运行时的兼容选择器 602 00:32:53,072 --> 00:32:56,573 Selector just means a kind of an identifier for a method. +selector 表示方法的一种标识符 603 00:32:56,575 --> 00:33:00,911 And here is just the class, a dot, and then the name of +这是处理方法的类、点，然后是 604 00:33:00,913 --> 00:33:04,648 the method including the argument names. Don't forget +包含参数名称的方法名称。 605 00:33:04,650 --> 00:33:07,951 the argument names here. Now, this pan method that I'm gonna +别忘了参数名称，我会在下一页说明 606 00:33:07,953 --> 00:33:11,989 show you on the next screen, it has one argument. +这个 pan 方法，只有一个参数 607 00:33:11,991 --> 00:33:14,958 That argument is the pan gesture recognizer. +而这个参数就是这个拖动手势识别器 608 00:33:14,960 --> 00:33:16,994 So just like when we have target action, and +就像我们有一个 target - action 方法 609 00:33:16,996 --> 00:33:19,863 we have a button that has the sender is sending itself. +一个 button 将自己作为 sender 传递 610 00:33:19,865 --> 00:33:22,332 Same thing here, when we have a pan gesture recognizer and +同样的，当我们有一个拖动手势识别器 611 00:33:22,334 --> 00:33:25,502 it starts to recognize, it sends this pan method +当它识别到手势时，它会将自己作为参数 612 00:33:25,504 --> 00:33:29,706 here to the view controller with itself as the argument. +调用 ViewController 的 pan 方法 613 00:33:29,708 --> 00:33:32,409 Now you might say, why is this underbar right here? +你可能会问，为什么有这个下划线呀？ 614 00:33:32,411 --> 00:33:35,345 Why don't I have the name of whatever this first keyword +为什么对于这个参数不能有一个名字 615 00:33:35,347 --> 00:33:39,349 is? And that's because I don't really care what that name is. +这是因为，我们不关心它的名字是什么 616 00:33:39,351 --> 00:33:39,883 I just wanna make it clear, +我只想让它保持优雅整洁 617 00:33:39,885 --> 00:33:44,221 I want the version of pan that has one argument. Now if I had +我希望这个 Pan 方法仅有一个参数 618 00:33:44,223 --> 00:33:49,426 multiple, pan methods that had different first, names there, +如果我需要多个参数，那么这里就需要参数名称 619 00:33:49,428 --> 00:33:52,829 then I would have to put the name in there. But I can put +我需要写名称，但是我可以 620 00:33:52,831 --> 00:33:56,133 underbar here because underbar in Swift means, I don't care, +在这里写下划线，因为在 Swift 中，下划线表示我不关心 621 00:33:56,135 --> 00:33:59,269 whatever, okay? I don't really care what this is. It's +我确实不关心这个参数名称的问题 622 00:33:59,271 --> 00:34:02,272 a substitute for I don't care. So I don't really care here. +下划线是我不关心这个问题的代名词 623 00:34:02,274 --> 00:34:05,675 So I just wanna introduce that you can do this underbar here. +我只是想说明你可以在这里用下划线替代参数名称 624 00:34:05,677 --> 00:34:09,179 But if I don't put this _:) here, then it's gonna try and - +但是，如果我在这里没有写 (_:) 625 00:34:09,181 --> 00:34:10,981 call a pan method that has no arguments. +它会调用一个没有参数的 pan 方法 626 00:34:10,983 --> 00:34:14,017 So be careful, if you want the one that has the gesture +在这里需要注意，如果你想将一个手势识别器 627 00:34:14,019 --> 00:34:17,854 recognizer as an argument, you gotta put that in there, okay? +作为参数调用，你得在这里写 (_:) 628 00:34:17,856 --> 00:34:21,458 So that's specifying the selector. And then I just turn +这是一个具体的选择器，然后 629 00:34:21,460 --> 00:34:25,562 on this recognizer by taking the view, this is the UIView, +我通过添加手势识别器到这个 view 也就是这个 pannableView 630 00:34:25,564 --> 00:34:30,434 this pannableView, okay? And adding this thing I created as +开启我的手势识别器 631 00:34:30,436 --> 00:34:34,504 a gesture recognizer, okay? As soon as I add that, +一旦我添加了手势识别器 632 00:34:34,506 --> 00:34:38,108 this view is gonna start recognizing pan gestures, +这个 view 就开始识别拖动手势 633 00:34:38,110 --> 00:34:41,378 okay? And when it does, it's gonna send this method to +当确实有拖动手势发生时，它会调用 controller 634 00:34:41,380 --> 00:34:46,516 self which is the controller, got it? Okay, makes sense, +中的处理方法 635 00:34:46,518 --> 00:34:48,985 that's what we're doing there? All right, so now, +我们在处理方法中干什么呢？ 636 00:34:48,987 --> 00:34:50,420 let's talk about how we implement this handler? +现在，我们讨论一下如何实现处理方法 637 00:34:50,422 --> 00:34:52,656 This method right here, this pan thing, okay? +这个 pan 方法 638 00:34:52,658 --> 00:34:57,060 What does that look like to implement? To, +它应该如何处理呢？ 639 00:34:57,062 --> 00:34:59,663 to understand how we're gonna implement such a method, we +为了明白我们在这个方法中如何处理手势事件 640 00:34:59,665 --> 00:35:02,766 needed to understand a little bit more about the concrete +我们需要知道关于 641 00:35:02,768 --> 00:35:04,668 subclasses of UI gesture recognizer. So +UIGestureRecognizer 继承实体类的一些知识 642 00:35:04,670 --> 00:35:09,272 let's look at pan, okay? So pan, UIPanGestureRecognizer, +关于UIPanGestureRecognizer 643 00:35:09,274 --> 00:35:12,943 it has a few methods on it that are specific to panning, +有一些专门处理拖动手势的方法 644 00:35:12,945 --> 00:35:15,045 okay? For example, it has translationInView. +比如，translationInView 方法 645 00:35:15,047 --> 00:35:19,783 It takes a UIView and tells you how far the pan has moved +它获取一个 UIView 参数，然后返回这个拖动手势 646 00:35:19,785 --> 00:35:23,053 in that view's coordinate system, okay? +在这个 view 的坐标中移动了多远 647 00:35:23,055 --> 00:35:25,789 Which is exactly what you want for a pan cuz you wanna know +这个方法确切的告诉你关于拖动手势你想知道的 648 00:35:25,791 --> 00:35:29,459 where you are, so calls wanted to know how far you moved? +也就是这个拖动手势移动了多远 649 00:35:29,461 --> 00:35:32,129 It even has velocity in view, we'll tell you how fast +甚至还有在这个 view 中，手指开始拖动的速度有多快 650 00:35:32,131 --> 00:35:34,998 the pan is happening, okay? If you're ripping it around +如果你在周围非常非常非常缓慢地 651 00:35:35,000 --> 00:35:36,833 versus going really really really really slow. +拖动手指 652 00:35:36,835 --> 00:35:39,002 Like if you had a drawing app, when you're going really slow, +像你有个画画的应用，当你非常缓慢地拖动手指 653 00:35:39,004 --> 00:35:40,270 you might be drawing really carefully. +这时就需要仔细绘图了 654 00:35:40,272 --> 00:35:41,271 And if you're zipping it around, +或者你在周围快速移动手指 655 00:35:41,273 --> 00:35:43,874 now you're making big arcs or something, who knows? And +你就需要画一个大的弧度之类的(因为手指移动速度快) 656 00:35:43,876 --> 00:35:47,511 it even has set translation, which is setting this. +在配置手势识别器时，甚至需要设置 translation 657 00:35:47,513 --> 00:35:48,845 Why would you ever want to set this? +为什么每次还得设置这个参数呢? 658 00:35:48,847 --> 00:35:53,583 Well, if you don't set this, okay? Then this translationVew +如果你不设置，之后 659 00:35:53,585 --> 00:35:56,620 is going to be the cumulative translationInView, +translationView 会变成一个递增的 translationView 660 00:35:56,622 --> 00:36:00,090 okay? It's how far the pan has moved since it started, +这个是你的拖动手势从开始到现在拖动的距离 661 00:36:00,092 --> 00:36:04,227 the cumulative thing. If you what you want instead is, how +是一个递增的值，如果你不设置 662 00:36:04,229 --> 00:36:07,831 much it's changed since last time you told me about it, +手势内容会是上一次你拖动的距离 663 00:36:07,833 --> 00:36:11,468 okay? You can constantly reset this to zero. +应将这个值重置为 0 664 00:36:11,470 --> 00:36:13,637 If you constantly reset this translation to zero, +如果你再下一次将得到这个值时 665 00:36:13,639 --> 00:36:14,504 then the next time you get it, +不断将它设置为 0 666 00:36:14,506 --> 00:36:18,408 it's gonna be the translation incremental, okay? Tiny bit, +这就会是一个递增的 translation 667 00:36:18,410 --> 00:36:21,411 little tiny bit it moves since the last time, okay? +基于每一次最后拖动的一点点距离 668 00:36:21,413 --> 00:36:24,748 So you'll see in the demo that we we will reset this to zero +一会儿在 demo 中你会看到我们每次将其重置为 0 669 00:36:24,750 --> 00:36:28,218 every time, cuz we just want the incremental panning, okay? +因为我们想要一个慢慢递增的拖动手势 670 00:36:28,220 --> 00:36:32,956 All right, so the abstract superclass of UI pan gesture +UIPanGesture 这个抽象的基类 671 00:36:32,958 --> 00:36:37,761 also provides a very important var, which is the state. +也提供了一些重要的属性，比如说手势的状态 672 00:36:37,763 --> 00:36:40,730 Okay, I told you that these gesture recognizers go through +我之前说过手势识别器是在不断检测 673 00:36:40,732 --> 00:36:44,568 a state machine, okay? And this is how you can find out +状态机的状态，你可以在处理方法中 674 00:36:44,570 --> 00:36:48,371 in your handler what state the gesture is in. +发现手势的状态 675 00:36:48,373 --> 00:36:52,409 So they all start around in this state possible, okay? +所以他们在 possible 状态开始识别 676 00:36:52,411 --> 00:36:55,478 UIGestureRecognizerState.Poss- ible. Then for +UIGestureRecognizerState.Possible 677 00:36:55,480 --> 00:36:59,015 a discrete gesture, like a swipe, once the swipe happens, +对于一个离散状态的手势，比方说扫动 678 00:36:59,017 --> 00:37:02,652 it immediately goes to the state recognized, okay? +这个手势很快就被识别到 679 00:37:02,654 --> 00:37:03,720 It recognized the swipe. So +手势识别器识别到扫动手势 680 00:37:03,722 --> 00:37:07,591 your handler gets called, the state will be recognized. For +处理方法被调用，这是状态就是 Recognize 681 00:37:07,593 --> 00:37:11,828 a continuous gesture like a pan or a pinch, okay? It goes +对于一个连续状态的手势，比方说拖动或捏合 682 00:37:11,830 --> 00:37:15,599 to the state Began as soon as the pan gets held down, and +当手势开始时，状态就是 Began 683 00:37:15,601 --> 00:37:18,768 as soon as the pan starts moving it keeps going to +手势一开始移动，状态就立即变为 Changed 684 00:37:18,770 --> 00:37:21,471 the state Changed. Change, change, change, change, +随着手势变化，状态一直是 Changed Changed Changed 685 00:37:21,473 --> 00:37:23,306 change, the handler keeps getting called over and +这样处理方法一直被调用调用调用 686 00:37:23,308 --> 00:37:25,208 over and over and over and over with Changed, okay? +因为状态一直是 Changed 687 00:37:25,210 --> 00:37:28,812 And every time this translation is changing, okay? +每次手势状态变化就会是 Changed 状态 688 00:37:28,814 --> 00:37:33,883 And then, when the finger goes up, then it goes to Ended. +最后，当手指抬起，状态就变为 Ended 689 00:37:33,885 --> 00:37:38,188 Make sense? Now there's couple other states here, Failed and +明白了吗？还有一些状态，Failed 690 00:37:38,190 --> 00:37:41,925 Cancelled. Like if you're doing the middle of a pan and +和 Cancelled，比如你正在做一个拖动手势 691 00:37:41,927 --> 00:37:43,760 a phone call comes in, okay? +一个电话进来了 692 00:37:43,762 --> 00:37:45,996 Then you're gesture is gonna get cancelled, +这个拖动手势就 Cancelled 了 693 00:37:45,998 --> 00:37:49,032 okay? So you might or might not have to deal with that. +通常你不用特别的处理这个状态 694 00:37:49,034 --> 00:37:52,035 If you're dealing with your pan incrementally, - +如果前面一直在处理这个拖动手势 + 695 00:37:52,037 --> 00:37:54,638 then who cares if it gets interrupted? +对于它突然被打断，我们并不需要关心这个 696 00:37:54,640 --> 00:37:55,605 You were moving the thing incrementally. +因为你打断之前你已经做了相关处理了 697 00:37:55,607 --> 00:37:58,074 If you are dealing with your pan with some big +如果你需要在拖动手势结束时 698 00:37:58,076 --> 00:38:01,678 thing at the end, when the pan ends, then you better do in +做一些操作，你最好在 699 00:38:01,680 --> 00:38:04,547 here what you were gonna do when it ended, okay? +状态变为 Ended 时操作 700 00:38:04,549 --> 00:38:07,617 But a lot of times you don't care cuz you're doing all +通常我们不用担心被打断 701 00:38:07,619 --> 00:38:09,919 the work in Changed so Cancelled and Failed is +因为大多数时候，操作都在状态为 Changed 时完成了 702 00:38:09,921 --> 00:38:13,256 just like Ended but you don't notice the finger going up. +Cancelled 和 Failed 就类似与一种手指没抬起时就 Ended 状态 703 00:38:13,258 --> 00:38:16,793 Well, no big deal. Okay, so now that I have all this +这不是什么大问题，现在 704 00:38:16,795 --> 00:38:17,927 information about a pan gesture, +我有了关于拖动手势的所有信息 705 00:38:17,929 --> 00:38:21,831 how do I make a handler that handles a pan gesture, okay? +我的处理方法应该如何处理这个拖动手势呢？ 706 00:38:21,833 --> 00:38:23,500 This is what the code would look like. This code is gonna +处理方法在这里 707 00:38:23,502 --> 00:38:25,969 be in my controller because I said the controller is gonna +这些应该写在 controller 中，因为我之前说过 708 00:38:25,971 --> 00:38:30,440 handle the pan. And first I'm gonna look at the state, okay? +controller应该处理这个手势， 首先我要看手势的状态 709 00:38:30,442 --> 00:38:35,111 Of the, okay, yeah, I'm sorry, here's that pan_:), +不是，先看 pan_:) 710 00:38:35,113 --> 00:38:37,380 you see, this pan takes an argument, +这个 pan 方法有一个参数 711 00:38:37,382 --> 00:38:39,983 okay? Instead of underbar there I could have put gesture +与写下划线相反的是，这里我写参数名为 gesture 712 00:38:39,985 --> 00:38:42,218 because that's what I called it here, gesture, but +因为后面是这么调用的，这是内部参数名 713 00:38:42,220 --> 00:38:45,188 I don't care. But, this one take an argument, +这里有一个参数 714 00:38:45,190 --> 00:38:47,190 you could have pan with no arguments here and +你也可以在这里不写参数 715 00:38:47,192 --> 00:38:50,293 nothing there and this would not pass the pan gesture along +不写参数的话就不会将拖动手势作为参数传递 716 00:38:50,295 --> 00:38:52,896 as an argument. But, here I need the pan gesture, +但在这里我需要这个拖动手势 717 00:38:52,898 --> 00:38:56,499 cuz I need to know how far the pan is gone, okay? So, next +因为我需要知道这个手势我拖动了多远 718 00:38:56,501 --> 00:39:00,370 I'm gonna switch on the state that the pan gesture is in and +下面，switch 这个拖动手势的 state 719 00:39:00,372 --> 00:39:05,608 if it's Changed Or Ended, then I am going to update something - +如果 state 是 Changed 或 Ended，我希望更新 720 00:39:05,610 --> 00:39:08,311 in my controller, okay? Otherwise, +在 controller 中的一些东西 721 00:39:08,313 --> 00:39:10,947 I'm gonna ignore it, okay? If it's Cancelled or Failed or +剩下的 state 会直接被忽略 722 00:39:10,949 --> 00:39:15,151 if it Began, I don't care. I'm only interested when it moves, - +在 Cancelled、Failed、Began 状态中不用处理，我只关心它移动的时候 + 723 00:39:15,153 --> 00:39:17,053 okay? So that's why I'm only looking at this. +这就是为什么我只找关于移动的状态 724 00:39:17,055 --> 00:39:19,656 Now, I wanna show you this kinda cool thing in Switch. +现在，我想给你看一些在 Switch 中很 cool 的东西 725 00:39:19,658 --> 00:39:22,459 Hopefully you got this in your homework? But there's this +希望你在作业中早已读过 726 00:39:22,461 --> 00:39:25,061 thing, fallthrough. Remember that Swift cases +就是 fallthrough，在 Swift 里 727 00:39:25,063 --> 00:39:28,631 don't fall through to the next case like they do in C, okay? +不像 C 跳转到下一个 case 方法(将 case 后语句置为空) 728 00:39:28,633 --> 00:39:31,368 But you can force them to fall through with fallthrough. +但是你可以通过添加 fallthrough 关键字跳转 729 00:39:31,370 --> 00:39:34,504 Now, I probably wouldn't write code like this, +代码也可以不这么写 730 00:39:34,506 --> 00:39:37,841 I would just say case.Changed, .Ended, okay? +直接写 case.Changed, .Ended 731 00:39:37,843 --> 00:39:39,442 That's a easier way to do this, but +这种方式更简单 732 00:39:39,444 --> 00:39:42,912 I just wanted to show you fallthrough, okay? All right, +我只是想秀一下 fallthrough 关键字 733 00:39:42,914 --> 00:39:46,616 so here inside, when things have Changed or Ended, +在这儿，当状态是 Changed 或 Ended 734 00:39:46,618 --> 00:39:50,653 I'm gonna get the translation in the pannableView. Okay, +可以得到 pannableView 的translation 735 00:39:50,655 --> 00:39:53,957 remember this to that outlet? I'm gonna get that translation +记得前面那个 outlet 吗？ 736 00:39:53,959 --> 00:39:56,559 from the gesture. And then I'm gonna go and +获得手势的 translation 737 00:39:56,561 --> 00:39:59,629 update something that depends on where the pan is. +然后更新一些取决于手势发生位置的操作 738 00:39:59,631 --> 00:40:02,966 I've got, I know where the pan, how far it has moved. So +现在我知道手势在哪里发生了、手势挪动了多远 739 00:40:02,968 --> 00:40:06,836 I'm just gonna update what, something that needs that. +给需要这些信息的操作更新信息 740 00:40:06,838 --> 00:40:10,039 And then I'm gonna set the translation back to 0. - +之后，将 translation 重置 + 741 00:40:10,041 --> 00:40:13,910 Okay, this also could be CGPoint.Zero if you want. But +需要的话，这将置为 CGPointZero 742 00:40:13,912 --> 00:40:15,078 see, I'm gonna set it back to 0 so +我想让它变为0 743 00:40:15,080 --> 00:40:17,113 that the next time I get called to my handler, +当下一次我调用处理方法时 744 00:40:17,115 --> 00:40:19,983 next time it comes back around, this translation will +又走到这一步 745 00:40:19,985 --> 00:40:23,520 be the incremental translation from the last time it sent it +translation 将从上一次我拖动到的地方继续拖动 746 00:40:23,522 --> 00:40:28,992 to me. Everybody get that? Please? Okay? All right. +大家明白吗？ 747 00:40:28,994 --> 00:40:30,560 So that's it. That's what the handler looks like. +在处理方法中大概就写这些 748 00:40:30,562 --> 00:40:32,896 Pretty straight forward. Okay. We'll see this in the demo, +处理的方法很简单，我们待会儿在 demo 中会继续讲这些内容 749 00:40:32,898 --> 00:40:36,933 it's not too bad, okay? Let's briefly talk about some of +我们简单讲一下除了拖动手势 750 00:40:36,935 --> 00:40:39,102 the other concrete gestures besides pan, +其他的手势实体类 751 00:40:39,104 --> 00:40:41,571 there's pinches. Pinches is two fingers down, - +比如捏合手势，捏合手势指 752 00:40:41,573 --> 00:40:44,741 pinching in and out like this, okay? And here what +两个手指像这样 753 00:40:44,743 --> 00:40:48,378 @@ -3013,686 +3261,854 @@ you're getting instead of the translation, it is the scale. 754 00:40:48,380 --> 00:40:51,581 So if I start my fingers here and I bring them out twice as +如果我把手指间距放宽到之前两倍 755 00:40:51,583 --> 00:40:55,185 wide that will be a scale of two. If I start him here and +这样 scale 会变为 2 756 00:40:55,187 --> 00:40:57,654 move him in half way, that's a scale 0.5. +如果我缩小到一半，scale 会变为 0.5 757 00:40:57,656 --> 00:41:01,791 Okay, so I'm scaling whatever on my screen and again I can +重复的在屏幕上进行捏合操作 758 00:41:01,793 --> 00:41:06,663 get velocity, how fast I'm pinching. Rotation is two +我可以得到 velocity 参数，代表我捏合的速度 759 00:41:06,665 --> 00:41:10,767 fingers turning them, okay. Like you're turning a knob and +旋转指两根手指转圈的手势，就像你旋转把手时 760 00:41:10,769 --> 00:41:14,337 it will tell you how many radians you've turned, okay. +会知道你旋转了多少度 761 00:41:14,339 --> 00:41:18,374 And again velocity, how fast you're turning. Swipe gesture, - +这个手势也有 velocity 参数表示你旋转的速度 + 762 00:41:18,376 --> 00:41:21,544 okay. The swipe gesture you usually have to configure - +轻扫手势，这个手势通常需要你配置参数 763 00:41:21,546 --> 00:41:24,147 before you use it. You have to say, do you want a left +在你用之前，你必须标明扫动方向 764 00:41:24,149 --> 00:41:27,484 going swipe, or right going swipe or up or down. Okay, and +是左是右，是上是下 765 00:41:27,486 --> 00:41:31,421 also two fingers swipe, or one finger or three fingers okay. +也需要配置手势是一个、两个还是三个手指操作 766 00:41:31,423 --> 00:41:34,324 You have to configure that then you add the gesture +你需要在添加手势之前配置好这些参数 767 00:41:34,326 --> 00:41:37,026 recognizer and it will only recognize it if all those +在当前手势符合这些你配置的参数之后 768 00:41:37,028 --> 00:41:39,896 things are true. Two finger swipe up has all the, +手势才会被识别到，你想识别到两根手指在这里扫动 769 00:41:39,898 --> 00:41:41,397 it has to be a two finger swipe up. +你的手势识别器就必须设置为两根手指的扫动 770 00:41:41,399 --> 00:41:44,334 Otherwise it doesn't recognize it, okay. So +不然的话，这个手势就不能被识别到 771 00:41:44,336 --> 00:41:48,037 that's swipe. Tap, which seems like it would be discreet, +这就是轻扫手势，下面轻击手势 772 00:41:48,039 --> 00:41:49,939 is not quite a discreet gesture, but +轻击手势不是一个很单一的手势 773 00:41:49,941 --> 00:41:52,108 you also configure it with how many taps. You know, +你仍需要配置点几下 774 00:41:52,110 --> 00:41:55,945 is it a single tap, or a double tap? And two fingers, +只是点一下还是双击？ 775 00:41:55,947 --> 00:41:59,415 or one? Okay, you configure that, add it, and here, you're +是两根手指点还是一根？ 你需要配置这些，添加手势 776 00:41:59,417 --> 00:42:03,853 gonna look for .ended to find out when the tap has happened, +然后当手势开始后，识别手势状态是否结束 777 00:42:03,855 --> 00:42:07,290 okay. That's because a tap actually has intermediate +这是因为轻击的手势有中间状态 778 00:42:07,292 --> 00:42:10,593 things going on like a double tap has a, the first tap. And +比方说，双击时第一下点完到第二下的状态 779 00:42:10,595 --> 00:42:12,929 then the second tap. And it might go through a state +这会在你处理方法中经历一个 780 00:42:12,931 --> 00:42:16,533 change that will call your handler, but +状态的变化 781 00:42:16,535 --> 00:42:20,236 it's not done yet. Okay and you can't look at recognized, +但是手势仍没结束，这时识别器就无法识别 782 00:42:20,238 --> 00:42:23,139 at recognized with tap because it's not a discreet gesture. +因为这不是一个简单手势 783 00:42:23,141 --> 00:42:25,675 Because it goes through those intermediate phases. +它经历了一个中间的状态 784 00:42:25,677 --> 00:42:29,245 So you really look for .ended for tap, okay. +所以你确实需要找到 ended 状态 785 00:42:29,247 --> 00:42:33,283 All right, so let's do a demo. Let's see all this in action +好的，现在我们开始在 demo FaceIt 中添加这些操作 786 00:42:33,285 --> 00:42:38,054 with our facet and what we're gonna do. First, I'm gonna add +首先需要做什么，我先添加 787 00:42:38,056 --> 00:42:41,190 a pinch gesture that makes our face get bigger and +一个可以让 face 变大变小的捏合手势 788 00:42:41,192 --> 00:42:43,493 smaller. Okay, we're just gonna pinch in and out and +通过手势的捏合调整 face 的大小 789 00:42:43,495 --> 00:42:47,530 adjust our scale. And then I'm gonna add a pan gesture. +然后，我需要添加一个拖动手势 790 00:42:47,532 --> 00:42:48,398 Actually I'll probably do a swipe. +哦不，我加的是轻扫手势 791 00:42:48,400 --> 00:42:53,002 Let's do a swipe gesture, that modifies our model, okay. +我们用轻扫手势修改我们的模型 792 00:42:53,004 --> 00:42:55,939 We're gonna use it to make our model happier or sadder. +用这个手势使模型快乐一点或者悲伤一点 793 00:42:55,941 --> 00:42:59,375 If I make it happier or sadder, then we'll adjust our +如果模型中的数据变化了，我们需要调整 794 00:42:59,377 --> 00:43:04,914 face view, okay. Let's do that. Back to our facet here. - +faceView 的状态，好了，回到FaceIt工程中 795 00:43:04,916 --> 00:43:09,419 All right, so how are we gonna do this? +我们如何做呢？ 796 00:43:09,421 --> 00:43:12,722 First thing we need to do is add a gesture recognizer, +首先，我们需要添加手势识别器 797 00:43:12,724 --> 00:43:16,759 okay. And again I said inside faceView didset is a good +再重复一遍我之前说的，faceView 的 didSet 方法是一个 798 00:43:16,761 --> 00:43:19,095 place to do that. So now I'm gonna expand this back out. +合适的时机添加手势识别器，现在我需要把括号中内容扩大 799 00:43:19,097 --> 00:43:21,998 Because I'm gonna add more code than just that one, +因为这里有一些代码超过一行了 800 00:43:22,000 --> 00:43:25,034 thing here, okay. And I'm still gonna update you, +添加完手势识别器，updateUI 801 00:43:25,036 --> 00:43:28,037 UI here, but I'm also going to add a gesture recognizer. +我添加完了手势识别器 802 00:43:28,039 --> 00:43:30,807 I know that this didSet is only gonna be called once +这个 didSet 方法只会在 803 00:43:30,809 --> 00:43:34,110 when my outlet is first hooked up to my UI, so that's perfect +outlet 绘制在UI上时被调用一次 804 00:43:34,112 --> 00:43:36,512 cuz I only wanna add the gesture recognizer once. And +所以这是一个添加手势识别器的完美时机 805 00:43:36,514 --> 00:43:39,582 I know that the faceView is the guy who has to recognize +faceView 需要识别到这个手势 806 00:43:39,584 --> 00:43:43,953 the gesture. Only views can recognize gestures. So +只有 view 可以识别手势 807 00:43:43,955 --> 00:43:48,024 I'm going to add a gesture recognizer. +我添加一个手势识别器 808 00:43:48,026 --> 00:43:50,994 Okay and you can see that when you add a gesture +你可以发现，当你添加一个手势识别器 809 00:43:50,996 --> 00:43:52,462 recognizer to a UI view it takes +给一个 view 810 00:43:52,464 --> 00:43:56,132 a gesture recognizer an argument. So I'm gonna create +它会把这个手势识别器当做参数 811 00:43:56,134 --> 00:44:00,703 one here, a UI pinch gesture recognizer, okay. And +所以我在这儿写 UIPinchGestureRecognizer 812 00:44:00,705 --> 00:44:04,374 that recognizer takes that target and action as they are, +创建这个识别器需要 target 和 action 813 00:44:04,376 --> 00:44:07,443 as the two arguments, right? So the target here, +作为两个参数 814 00:44:07,445 --> 00:44:11,381 in this case, since that pinch is only changing the scale +在这个例子中，因为捏合手势只是改变了 815 00:44:11,383 --> 00:44:13,216 of the view, it's not changing my model, +这个 view 的大小，并不会改变我的model 816 00:44:13,218 --> 00:44:18,488 I'm gonna let the face view handle this thing itself. Now, +所以我让 FaceView 自己处理这个手势 817 00:44:18,490 --> 00:44:21,157 for the FaceView to handle it, it's going to have to make +如果 FaceView 自己处理这个方法，但我需要在controller中 818 00:44:21,159 --> 00:44:25,728 some sort of gesture handler available to my controller. +调用这个方法，这个 FaceView 的方法必须可以让 controller 调用到 819 00:44:25,730 --> 00:44:28,765 So it's gonna have the public method right, +所以我需要在这里写一个 public 方法 820 00:44:28,767 --> 00:44:30,133 that handles a pinch. +来处理 pinch 手势 821 00:44:30,135 --> 00:44:32,969 So we're gonna have to add that to FaceView which will do +下一步，我们应该给 FaceView 添加处理方法 822 00:44:32,971 --> 00:44:36,606 next. And the action here is gonna be a selector, +这里的 action 必须是一个 selector 823 00:44:36,608 --> 00:44:41,477 it's gonna be a FaceView selector. FaceView selector. +是 FaceView 的 selector 824 00:44:41,479 --> 00:44:44,614 And I'm gonna call it changeScale, okay. +我叫它 changeScale 825 00:44:44,616 --> 00:44:49,318 And I am definitely going to need the argument there. +我这里确实需要参数 826 00:44:49,320 --> 00:44:52,422 So I'm gonna do that, as well, okay. +我马上添加参数 827 00:44:52,424 --> 00:44:56,459 Maybe this is a little easier to see if I do this. +我处理的方法很简单 828 00:44:56,461 --> 00:45:02,865 Like that. Okay. So it gives me an error here because +这儿有一个 error 829 00:45:02,867 --> 00:45:05,635 of course this method doesn't exist. So it's nice that it +因为这个方法还没有写，这样很好 830 00:45:05,637 --> 00:45:08,404 actually checks to make sure that this exist, okay. +因为每次会检查这个方法是否存在 831 00:45:08,406 --> 00:45:11,140 So let's go ahead and add this method right here, okay. This +现在让我们直接给 FaceView 添加这个方法 832 00:45:11,142 --> 00:45:14,644 is the method that's going to handle when a pinch happens, +这个方法将在每次捏护手势发生时被调用 833 00:45:14,646 --> 00:45:16,446 okay. We're gonna put that in our FaceView, so +我们在 FaceView 中写这个方法 834 00:45:16,448 --> 00:45:18,347 I'm gonna go over here to FaceView. +回到 FaceView 835 00:45:18,349 --> 00:45:20,883 Put it up here towards the top since it's gonna be public, +在上面一点写这个方法，因为他是公用的方法 836 00:45:20,885 --> 00:45:23,486 okay. It has to be public, because the controller +因为 controller 希望在处理手势的时候 837 00:45:23,488 --> 00:45:27,657 wants the gesture handler to call it. So changeScale. It's +调用这个方法，改变 FaceView 的大小 838 00:45:27,659 --> 00:45:31,427 going to have a recognizer as its argument, okay? +这里需要将一个手势识别器作为参数 839 00:45:31,429 --> 00:45:36,566 That UIPinchGestureRecognizer. Okay, +这个参数是 UIPinchGestureRecognizer 840 00:45:36,568 --> 00:45:39,902 so it's nice that when we're asked to handle the gesture, +每次我们需要处理这个手势时， 841 00:45:39,904 --> 00:45:42,505 the recognizer is passed along to us. +controller 将识别器作为参数传递给我们，这样很好 842 00:45:42,507 --> 00:45:44,540 And, this is really easy to implement, +实现起来也很简单 843 00:45:44,542 --> 00:45:49,879 I'm just gonna switch on the recognizer state. And +我需要 switch 手势识别器的状态 844 00:45:49,881 --> 00:45:52,115 if the state is changed or +如果这个状态 Changed 845 00:45:52,117 --> 00:45:57,186 ended, and yes you can do it that way in switches, in Swift +或者 Ended ，在 Swift 你可以这么写 846 00:45:57,188 --> 00:46:00,656 you can have multiple things there. If it's changed or +你可以写多个 case 在这里 847 00:46:00,658 --> 00:46:03,993 ended then I'm just gonna set my scale to be multiplied +如果手势状态 Changed 或者 Ended，我需要通过 848 00:46:03,995 --> 00:46:08,965 by the recognizer scale. Okay cuz here's my scale up here. +手势的大小设置 view 的大小，这是原来的 scale 849 00:46:08,967 --> 00:46:13,436 And so if this pinch goes 2.0 twice as wide, +如果捏合手势变成两倍大小 850 00:46:13,438 --> 00:46:16,272 then I want my scale to be twice of what it was. And +然后我就需要重置 scale 的大小为两倍 851 00:46:16,274 --> 00:46:17,673 if it goes down to 0.5, I want my scale +如果手势变为原来一半，我的 scale 852 00:46:17,675 --> 00:46:20,743 to be 0.5 of what it was. Okay, but this is gonna +就需要变为 0.5 这个过程 853 00:46:20,745 --> 00:46:24,380 be repeatedly called as that thing is moving in and out, so +随着手势的变化会被重复调用 854 00:46:24,382 --> 00:46:30,219 I need to make sure here that I reset the recognizer scale +所以我总是需要重置识别器的大小为1 855 00:46:30,488 --> 00:46:33,589 to 1.0 all the time. So that, as it moves out, +随着手势变化 856 00:46:33,591 --> 00:46:37,126 it's going to be give me the incremental scale in and out. +这里需要一个递增的 scale 值 857 00:46:37,128 --> 00:46:40,630 Because I'm actually applying the scale change every single +因为每次移动时都会应用这个 scale 858 00:46:40,632 --> 00:46:45,468 time it moves, every .Changed here I'm applying the scale, +在手势 Changed 时，我需要应用 scale 859 00:46:45,470 --> 00:46:49,005 okay. Now of course we need to have the default, +当然也需要这个 default 860 00:46:49,007 --> 00:46:53,709 state which is cancel, it covers cancelled and began and +当手势 Cancel 等状态，他包括了Cancel、Began 861 00:46:53,711 --> 00:46:53,876 all those things. +等等状态 862 00:46:53,878 --> 00:46:56,179 And it those case statuses I'm just gonna do nothing because +当识别到这些状态我什么也不做 863 00:46:56,181 --> 00:46:59,215 I'm actually tracking the scale and implementing it +因为实际上追踪 scale 变化和执行这些变化 864 00:46:59,217 --> 00:47:02,585 as it goes along, so I don't even care when it ends, okay. +是一直进行的，所以不用关心什么时候手势结束了 865 00:47:02,587 --> 00:47:06,389 I mean, it's nice when the fingers go up to do that one +在手指抬起时再做一次 866 00:47:06,391 --> 00:47:09,158 last adjustment of the scale but it's not crucial. Okay, +尺寸大小的调整是很好，但是并不是必须的 867 00:47:09,160 --> 00:47:11,661 and if we were cancelled, we wouldn't get that opportunity +当他 Cancelled 我们不需要获取到这个时机 868 00:47:11,663 --> 00:47:15,131 anyway. Okay, everyone understand that? +大家明白了吗？ 869 00:47:15,133 --> 00:47:21,737 This is a public method, yeah. >> [INAUDIBLE] +这是一个 public 方法 870 00:47:21,739 --> 00:47:22,238 >> Well, yeah, see I'm, this + [提问] 871 00:47:22,240 --> 00:47:24,507 is why I ask three or four times, everybody getting this. +这就是为什么我问了三四次大家明白了吗 872 00:47:24,509 --> 00:47:25,808 And everyone was kind of like yeah, I think so. +大家都是一副我懂了的样子 873 00:47:25,810 --> 00:47:30,179 Okay. The reason for this is, if I don't do this, okay, +为什么这么做呢？因为如果我不重置 scale 大小 874 00:47:30,181 --> 00:47:34,517 then as I pinch, I'm gonna get the cumulative scale, okay. So +在 pinch 手势中，我会得到一个累积的 scale 875 00:47:34,519 --> 00:47:37,520 let's say I start here, okay. And I start moving it out, +我这么说，手势开始移动来 876 00:47:37,522 --> 00:47:39,021 moving it out. And it's getting called changed, +移动去，它会调用 Changed 877 00:47:39,023 --> 00:47:43,726 change, change, change, okay. First time it's 1.1, 1.2, 1.3, +Changed、Changed，scale 会变为 1.1, 1.2, 1.3, 878 00:47:43,728 --> 00:47:46,128 1.4, 1.5, 1.6, 2.0, okay. +1.4, 1.5, 1.6, 2.0 879 00:47:46,130 --> 00:47:49,198 So it's getting called seven times with all those numbers. - +这些数字代表 Changed case 会被执行七次 880 00:47:49,200 --> 00:47:52,501 Imagine if I took my scale and multiplied it times by 1.0. +想象一下，我首先将这个 scale 乘以 1.0 881 00:47:52,503 --> 00:47:54,937 And then I multiplied it times 1.2, 1.3, 1.4. +之后乘以 1.2, 1.3, 1.4. 882 00:47:54,939 --> 00:47:57,306 Now the scale's getting gigantic. Okay, +现在这个 scale 会变得十分巨大 883 00:47:57,308 --> 00:48:00,943 that's not what I want. What I want is the incremental scale. +这可不是我想要的，我想要的是一个递增的 scale 884 00:48:00,945 --> 00:48:03,679 So if I keep resetting it to 1, then when it gets a little +所以我一直将 scale 重置为1 885 00:48:03,681 --> 00:48:07,116 bigger, I'm gonna get 1.01 again, okay? Reset to 1, +当 scale 变大时，会乘以 1 886 00:48:07,118 --> 00:48:11,621 1.01 again, you see? Exactly, I'm not by the scale. Now, +再乘以 1.01 你明白了吗？我不会直接乘以之前的 scale 887 00:48:11,623 --> 00:48:14,757 the alternative is, I could just have the pinch do nothing +也可以在这里不重置 888 00:48:14,759 --> 00:48:17,793 until you let go and then I could set the scale, okay? +直接让 scale 变化，之后再重置 889 00:48:17,795 --> 00:48:18,928 But, since I'm doing it incrementally, +但是，因为我想要让 scale 递增 890 00:48:18,930 --> 00:48:23,966 I have to keep resetting it to 1, okay? Good question. All +就需要每次将它重置为 1 891 00:48:23,968 --> 00:48:27,436 right, so now if we go back to our FaceViewController, +现在，我们回到 FaceViewController 中 892 00:48:27,438 --> 00:48:29,939 you'll see that we don't have an error here anymore on this +你可以看到这时这里就不再有 error 了 893 00:48:29,941 --> 00:48:33,876 line because we've actually defined this handler, okay? So +因为我确实定义了处理手势的方法 894 00:48:33,878 --> 00:48:39,415 now when we run, and we pinch. We're gonna update the scale, +现在我们运行、做捏合手势，这个 view 的 scale 就会被更新了 895 00:48:39,417 --> 00:48:40,683 hopefully, of our face. +希望如此 896 00:48:40,685 --> 00:48:42,952 So here's our face. He doesn't look very happy, but +这是 face ，它看起来不怎么高兴 897 00:48:42,954 --> 00:48:45,755 I'm going to make him smaller, so we won't notice, okay? Now, +但是一会儿我们让它高兴些，现在先不用在意 898 00:48:45,757 --> 00:48:48,958 you might ask, how am I gonna pinch with my mouse, okay? +你可能会问，我只有一个鼠标，怎么做捏合手势 899 00:48:48,960 --> 00:48:51,594 I've got my mouse here, I can't, just a little, +我把鼠标放这里，怎么捏合呢？ 900 00:48:51,596 --> 00:48:55,564 how am I gonna do it? And the answer is, Option, okay? +答案是，Option 键 901 00:48:55,566 --> 00:48:56,198 If you're running the simulator and +如果你运行模拟器 902 00:48:56,200 --> 00:48:59,669 you hold down Option, look. Two fingers come up there, +按下 Option键后，就出现两根手指了 903 00:48:59,671 --> 00:49:04,874 -okay? Now you can mouse down and drag and it's like you're +okay? Now you can mouse down and drag and it's like you’re +你可以用鼠标移动它 904 00:49:04,876 --> 00:49:09,512 pinching. You see, pinching in pinching out, +看起来你想在做捏合手势，放大放小 905 00:49:09,514 --> 00:49:15,351 okay? Got it, so you can see these gesture hands +你看这些手势 906 00:49:15,353 --> 00:49:19,255 are super easy to implement, okay? We probably had four +做起来很简单的，我们可能 907 00:49:19,257 --> 00:49:22,725 lines of code there, of actual lines of code. All right, +就写了几行代码吧 908 00:49:22,727 --> 00:49:25,761 now, let's do another gesture recognizer, okay? Let's have +现在，我们添加另一个手势识别器 909 00:49:25,763 --> 00:49:28,464 this one modify our model. So what I'm gonna do here is, +这个手势会改变我们的模型，所以我需要在这里 910 00:49:28,466 --> 00:49:32,368 I'm gonna make it so that when I swipe down, he gets sadder. +当我向下扫动时，它看起来更悲伤 911 00:49:32,370 --> 00:49:33,069 And when I swipe up, +向上扫动时 912 00:49:33,071 --> 00:49:37,039 he gets happier in a model sense, okay? Okay, +它看起来高兴一点 913 00:49:37,041 --> 00:49:38,007 I'm gonna make the model happier. +需要改变 model 属性让它更高兴 914 00:49:38,009 --> 00:49:40,643 I'm not gonna move my mouth curvature. I'm gonna change +我需要设置嘴巴弯曲的程度，这将会改变 model 属性 915 00:49:40,645 --> 00:49:42,812 the model. Now of course, every time I change the model, +每一次我改变了 model 916 00:49:42,814 --> 00:49:44,981 that's going to change my mouth curvature. So +就会改变嘴巴的弯曲程度 917 00:49:44,983 --> 00:49:47,149 it's gonna work. But we're gonna change the model. +我们需要改变 model 918 00:49:47,151 --> 00:49:50,353 So to do that, I'm gonna do a swipe gesture. +为了实现这个功能，我将加一个轻扫的手势 919 00:49:50,355 --> 00:49:51,887 Now, a swipe gesture we have to configure. +轻扫手势需要我们做一些配置 920 00:49:51,889 --> 00:49:55,725 So I'm to create a local variable to hold it, okay? +创建一个局部变量保存这个手势识别器 921 00:49:55,727 --> 00:50:00,396 I am gonna call this local variable, +这个局部变量叫做 922 00:50:00,398 --> 00:50:05,201 my happierSwipeGestureRecognizer, +happierSwipeGestureRecognizer 923 00:50:05,203 --> 00:50:10,806 and so I say UISwipeGestureRecognizer. +UISwipeGestureRecognizer 方法创建 924 00:50:10,808 --> 00:50:11,007 SwipeGestureRecognizer and same arguments though, +与之前一样的参数 925 00:50:11,009 --> 00:50:15,411 @@ -3701,302 +4117,377 @@ Oops, 926 00:50:15,413 --> 00:50:19,982 target and action, okay? So the target here, okay, +需要设置 target 和 action，target 就是这个 927 00:50:19,984 --> 00:50:23,953 is not going to be the faceView because it modifies +target 不会是 faceView 了 928 00:50:23,955 --> 00:50:28,457 the model, it's gonna be self. Okay, +因为这个手势会改变 model，应该是 self 929 00:50:28,459 --> 00:50:31,560 controller has to be the one handling this one, okay? +controller 应该来处理这个手势 930 00:50:31,562 --> 00:50:36,032 And the action, which is the selector, is going to be +action 应该是一个 controller 的方法 931 00:50:36,501 --> 00:50:41,804 a FaceViewController selector, not a FaceView one. +并不是 FaceView 中的方法了 932 00:50:41,806 --> 00:50:45,107 And we'll call this thing we'll do, +我们会调用这个处理方法 933 00:50:45,109 --> 00:50:48,511 we'll make this be the happier one, so this is swipe up, so +我们希望这个方法能让 FaceView 开心些 934 00:50:48,513 --> 00:50:52,748 we'll call this increaseHappiness, okay? +这个方法被命名为 increaseHappiness 935 00:50:52,750 --> 00:50:55,017 And I don't need the swipe gesture +调用这个方法时，我就不需要这个轻扫手势了 936 00:50:55,019 --> 00:50:57,353 because it's either gonna be recognized or not. So +可以将它作为参数传递或者不传 937 00:50:57,355 --> 00:50:58,854 I'm not gonna have any arguments +我不需要任何参数 938 00:50:58,856 --> 00:51:03,092 to that increaseHappiness method, okay? +来调用 increaseHappiness 939 00:51:03,094 --> 00:51:05,061 Okay, I'll do the same thing here so +这里我会写这个 940 00:51:05,063 --> 00:51:08,297 you can see this a little better, okay? So this is not, +这样写好一些 941 00:51:08,299 --> 00:51:11,233 this guy right here is not going to have any arguments. +这个方法不需要写任何参数 942 00:51:11,235 --> 00:51:15,304 So that's gonna be a func, okay? increaseHappiness, +所以只是一个 increaseHappiness 943 00:51:15,306 --> 00:51:18,641 no arguments. And when the increaseHappiness happens, +不包括参数，当 increaseHappiness 被调用时 944 00:51:18,643 --> 00:51:22,144 what are we gonna do to our model, okay? Well, +我们需要修改model 945 00:51:22,146 --> 00:51:25,581 we're just gonna say that our facial expression's mouth +我们 expression.mouth 946 00:51:25,583 --> 00:51:30,753 equals the expression's mouth.happierMouth. +等于 expression.mouth.happierMouth 947 00:51:30,755 --> 00:51:34,323 Okay, so if you look at our facial expression over here, +如果你回过头看 FacialeExpression 类 948 00:51:34,325 --> 00:51:37,293 okay, mouth okay? +枚举类型 Mouth 949 00:51:37,295 --> 00:51:40,863 This enum has two methods, sadderMouth and happierMouth, +这个枚举有两个方法，sadderMouth 和 happierMouth 950 00:51:40,865 --> 00:51:44,133 which will take the current mouth and make it sadder or +这个方法将改变当前的表情，更悲伤 951 00:51:44,135 --> 00:51:47,236 happier and return a new mouth, okay? So +或者更高兴，并且返回一个新的 Mouth 枚举类型 952 00:51:47,238 --> 00:51:51,941 it's just gonna go more happy or less happy along here. +使表情高兴一点或者是更高兴 953 00:51:51,943 --> 00:51:57,880 Okay, so we got that. Now so that's gonna be fine. +好了，我们现在写完了 954 00:51:57,882 --> 00:52:02,017 This swipe gesture though, we have to add it to our view. +这个轻扫手势我们需要添加到 view 上 955 00:52:02,019 --> 00:52:03,085 We have to do addGestureRecognizer. +我们需要 addGestureRecognizer 956 00:52:03,087 --> 00:52:06,021 We haven't done that. And we also have to configure it. +这一步还没写，我们还需要配置这个手势识别器 957 00:52:06,023 --> 00:52:08,791 So let's configure it. This is happier. So +这个是更高兴的手势 958 00:52:08,793 --> 00:52:13,596 I'm gonna have the hype, the SwipeGestureRecognizerDirect- +所以我需要配置 SwipeGestureRecognizerDirection 959 00:52:13,598 --> 00:52:18,834 ion. Okay, which is the direction of the swipe, +设置轻扫手势的 direction 为 960 00:52:18,836 --> 00:52:22,138 = .Up. Okay, so you're swiping up, that's for +Up, 好了，当你向上扫动时 961 00:52:22,140 --> 00:52:23,572 happier, and now we, and +表情看起来会更高兴 962 00:52:23,574 --> 00:52:28,177 it will have it be a single finger swipe, not two. And so +是一个手指扫动不是两个 963 00:52:28,179 --> 00:52:33,382 now I can just say faceView.addGestureRecognizer- +现在，我们可以给 faceView 添加手势识别器 964 00:52:33,384 --> 00:52:38,988 (happierSwipeGestureRecogniz- er), okay? +happierSwipeGestureRecognizer 965 00:52:39,357 --> 00:52:43,259 Make sense there? All right, let's go try this. +明白了吗？ 966 00:52:43,261 --> 00:52:45,761 Now notice every time we change the expression here, +现在每一次我们改变了 expression 967 00:52:45,763 --> 00:52:48,430 it's gonna automatically update our UI because of this +将会自动更新 UI 968 00:52:48,432 --> 00:52:52,201 didSet. You see that? We changed this expression, boom, +因为expression 的 didSet 方法里 969 00:52:52,203 --> 00:52:55,571 updateUI. So, let's try it. All right, so, +有 updateUI 再运行一次 970 00:52:55,573 --> 00:52:56,238 hopefully this is still working. +希望能奏效 971 00:52:56,240 --> 00:52:58,741 Pinching, yes, still working. Now I'm gonna swipe up and +捏合手势还可以进行，现在我想 972 00:52:58,743 --> 00:53:03,245 sure enough, he's getting happier and happier. Okay, but +向上扫动，它变得高兴一点儿了 973 00:53:03,247 --> 00:53:05,481 we better do swipe down also, okay? +但是向下扫动没有效果 974 00:53:05,483 --> 00:53:08,350 We don't have all only swipe up, let's get swipe down in +我们不能只写向上扫动的方法，还得写向下扫动的 975 00:53:08,352 --> 00:53:10,719 there. In fact, I'm gonna do that by copying and +事实上，因为向上和向下的代码差不多一样 976 00:53:10,721 --> 00:53:13,455 pasting because it's almost the same as this. +我要复制粘贴这段代码 977 00:53:13,457 --> 00:53:18,360 I'm just gonna replace this happier here with sadder. +将 happier 替换为 sadder 978 00:53:21,465 --> 00:53:25,501 And instead of it being an up swipe, it's gonna be a down +将向上替换为向下 979 00:53:25,503 --> 00:53:28,871 swipe. And instead of increasing the happiness, +增加高兴值变成 980 00:53:28,873 --> 00:53:30,973 it's going to decrease the happiness. +降低高兴值 981 00:53:30,975 --> 00:53:37,479 So I need a new method here called decreaseHappiness. +现在我需要一个新的方法叫 decreaseHappiness 982 00:53:38,216 --> 00:53:42,451 And this one's going to get the sadderMouth, okay? +设置为 sadderMouth 983 00:53:42,453 --> 00:53:45,454 Everyone understand, it's real important to understand here +大家都明白了吗？明白这个十分重要 984 00:53:45,456 --> 00:53:48,457 that we have recognizers that as they're being handled, +我们写好了手势识别器 985 00:53:48,459 --> 00:53:49,658 they're being handled by the controller. +手势被 controller 所识别 986 00:53:49,660 --> 00:53:53,829 And the controller's modifying the model. And since, and +controller 也将改变 model 987 00:53:53,831 --> 00:53:56,865 every time the model gets modified, it calls updateUI. +每一次，model变化了，就会更新 UI 988 00:53:56,867 --> 00:54:00,469 updateUI is the thing that's going to update, in this case, +updateUI 就是在这个例子中就是更新 faceView 989 00:54:00,471 --> 00:54:04,940 the mouth curvature. Everybody understand that flow? Okay, so +嘴巴的弯曲程度，大家都明白这个流程了吗？ 990 00:54:04,942 --> 00:54:11,647 let's make sure that swipe down is working. All right, +现在让我们看看轻扫手势生效了吗 991 00:54:11,649 --> 00:54:16,118 so swipe down, sad. Swipe up, happy, okay? Sad, +向下扫动，变悲伤，向上扫动，变高兴了 992 00:54:16,120 --> 00:54:21,023 happy, got it? All right, let's do one more gesture. +让我们再做些手势 993 00:54:21,025 --> 00:54:24,593 This one, when you tap, he's gonna open and close his eyes. +当你点击时，它会睁开或者闭上它的眼睛 994 00:54:24,595 --> 00:54:27,162 Every tap will toggle the opening and closing the eyes. +每一次轻击就会在睁眼或闭眼中切换 995 00:54:27,164 --> 00:54:30,165 Now I'm gonna do this one a little bit different, because +现在，我想用不一样的方法写这个手势 996 00:54:30,167 --> 00:54:32,868 we added all these gesture recognizers in code here. +因为我们在这里添加了所有的手势识别器代码 997 00:54:32,870 --> 00:54:35,271 You see how this adding GestureRecognizer in code? +你想看看我怎么添加新手势吗？ 998 00:54:35,273 --> 00:54:41,977 You can actually add these things in your storyboard, +你完全可以在 storyboard 中添加手势 999 00:54:41,979 --> 00:54:46,115 okay? So let's go over to our storyboard, right here, +现在来到 storyboard 1000 00:54:46,117 --> 00:54:51,687 okay? Let's get our controller onscreen at the same time, +同时，让 controller 同时出现在屏幕上 1001 00:54:51,689 --> 00:54:53,989 From d0b91d6d53da5d29ce47cf33adf236999fa097e4 Mon Sep 17 00:00:00 2001 From: saitjr Date: Sun, 4 Dec 2016 17:26:31 +0800 Subject: [PATCH 16/23] 800~1000 --- .../8. Multithreading and Text Field.srt | 214 +++++++++++++++++- 1 file changed, 208 insertions(+), 6 deletions(-) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index d30606b..fe55ef7 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -4036,810 +4036,1012 @@ let's do a demo of this where let's fix Cassini. 808 00:41:41,366 --> 00:41:44,934 Okay, let's make Cassini so that it's UI's always +优化一下 Cassini 的 UI， 809 00:41:44,936 --> 00:41:49,606 responsive even while it's off downloading these things. +使之在有下载任务的时候，也能及时响应事件. 810 00:41:49,608 --> 00:41:53,376 All right lets go over here. +那么从这里开始吧. 811 00:41:53,378 --> 00:41:55,445 Okay, all this is gonna be, all this code that we're going +先处理这些，这些在 ImageViewController 812 00:41:55,447 --> 00:41:57,514 to have to do is going to be in our ImageViewController. +中的代码. 813 00:41:57,516 --> 00:41:59,916 We're going to make our ImageViewController, so +先要将 ImageViewController 改为 814 00:41:59,918 --> 00:42:02,952 that it is asynchronous, right? That it can load things +异步处理，这样就能异步 815 00:42:02,954 --> 00:42:05,522 asynchronously. Before I do that actually though, +加载数据. 在实际操作之前， 816 00:42:05,524 --> 00:42:07,524 I wanna talk one other thing we should be doing here, +我还要讲到一件事， 817 00:42:07,526 --> 00:42:08,958 probably, in ImageViewController. +需要在 ImageViewController 中注意的事. 818 00:42:08,960 --> 00:42:12,495 Notice that if someone sets our model, we immediately go +注意这里有一段设置模型的代码，我们在里面 819 00:42:12,497 --> 00:42:17,133 off and fetch it, okay? Now what if we never appeared on +获取数据. 但如果我们从未将它展示在 820 00:42:17,135 --> 00:42:21,437 screen? Okay, what if this or something that's in a, +屏幕上呢？如果这是个， 821 00:42:21,439 --> 00:42:24,207 gonna be in a navigation controller, it got created, +这是个 navigation controller 之类的，虽然创建了， 822 00:42:24,209 --> 00:42:27,710 but no one ever clicked to cause it to happen on screen, +并且进行了模型设置， 823 00:42:27,712 --> 00:42:28,311 but someone set our model. +但是从来没有经过点击事件展示到屏幕上. 824 00:42:28,313 --> 00:42:30,980 Then this wouldn't happen in Cassini, this app, but imagine +虽然这问题不会出现在 Cassini 中，但是要小心在 825 00:42:30,982 --> 00:42:35,418 an app where you've got this image MVC and some incentive. +其他 app 中重用这个 image 的 MVC 结构或逻辑的情况. 826 00:42:35,420 --> 00:42:37,186 Really we really wouldn't want to do this +千万不要出现这种额外的资源消耗， 827 00:42:37,188 --> 00:42:39,789 fetch cuz it could be very expensive as we've seen, +这种资源占用非常昂贵. 828 00:42:39,791 --> 00:42:40,623 right? It goes on the network, +明白吗？这需要用到网络， 829 00:42:40,625 --> 00:42:42,292 it's pulling down this thing if I'm paying for +要从网络上拉去数据，而如果我允许 830 00:42:42,294 --> 00:42:44,928 cellular data, it's costing me money! Okay, +蜂窝数据，这会产生费用的！ 831 00:42:44,930 --> 00:42:47,931 to get that Cassini image, so I probably don't want to do +所以，除非是在显示到屏幕上时， 832 00:42:47,933 --> 00:42:51,968 this fetch image unless I'm on screen. If I'm on screen, +我才会去获取 Cassini 的图片数据. 只有在屏幕上时， 833 00:42:51,970 --> 00:42:55,004 I definitely want to do this. So here I'm going to say how +我才需要这样做. 那么，如何判断是否在 834 00:42:55,006 --> 00:42:58,341 can I tell if I'm on screen? If my view, okay, +屏幕上呢？如果这个 view， 835 00:42:58,343 --> 00:43:03,913 this is my MVC's view the top level, if it's window +即 MVC 结构中最顶层的 view，它的 window 836 00:43:03,915 --> 00:43:08,618 is not nil. Okay, that's a pretty reliable way to tell, +不是 nil. 则说明视图在屏幕上， 837 00:43:08,620 --> 00:43:12,989 sorry, that you are on screen, right? Because your view, +这种验证方式很靠谱. 因为你的 view， 838 00:43:12,991 --> 00:43:15,692 -your nbc's view will not be in a window unless it's on +your mvc's view will not be in a window unless it's on +你的 mvc view 不在屏幕上，才获取不到 window. 839 00:43:15,694 --> 00:43:19,529 screen. Make sense? We haven't talked about window much. +明白吗？我们目前还没讲到太多 window 的知识. 840 00:43:19,531 --> 00:43:22,765 It's that UI Window class I told you that you really never +它就是之前我告诉你们的， 841 00:43:22,767 --> 00:43:23,299 use it, and you don't. +永远不要用，并且你们也没有用的那个 UIWindow 类. 842 00:43:23,301 --> 00:43:26,436 You're not going to send any messages to it here. But +这里不需要调 window 的方法， 843 00:43:26,438 --> 00:43:26,569 whether it's nil or +直接判断它是否是 nil， 844 00:43:26,571 --> 00:43:29,105 not will tell you whether your view is on screen. +就能告诉你 view 是否在屏幕上. 845 00:43:29,107 --> 00:43:32,342 Now what happens though if someone sets my image URL like +那么，现在如果有人在 prepareForSegue 或者 846 00:43:32,344 --> 00:43:36,713 in a prepare for segue and then I do go on screen later? +视图展示在屏幕上时，设置了图片 URL， 847 00:43:36,982 --> 00:43:39,349 Now I have to fetch that image, okay? Cuz now I +我就回去获取图片数据. 因为下一步肯定能 848 00:43:39,351 --> 00:43:41,918 am going to go on screen. So how can I find out in my view +展示到屏幕上. 那么如何得知 view controller 849 00:43:41,920 --> 00:43:44,487 controller lifecycle that now I'm gonna go on screen, +生命周期中，何时展示到屏幕上呢？ 850 00:43:44,489 --> 00:43:49,993 which method? Which method in my view controller lifecycle? +哪个方法？view controller 生命周期中的哪个方法？ 851 00:43:49,995 --> 00:43:54,497 Do you remember? It called. I'll put it down here +还记得吗？它叫做... 852 00:43:54,499 --> 00:43:59,302 next to this viewDidLoad one. ViewWillAppear. Okay, so +和 viewDidLoad 写在一起吧. 叫做，viewWillAppear. 853 00:43:59,304 --> 00:44:02,071 viewWillAppear is sent to you when you're about to appear on +在即将展示到屏幕上时，会调用 viewWillAppear 方法. 854 00:44:02,073 --> 00:44:06,509 screen. Okay and we always do super.viewWillAppear in +对于 view controller 声明周期的方法， 855 00:44:06,511 --> 00:44:10,146 all these view controller life cycles, all right. So, +我们通常会先调用父类的方法，super.viewWillAppear. 856 00:44:10,148 --> 00:44:14,050 here I'm going to say if my image is nil, +在这里判断，如果 image 是 nil， 857 00:44:14,052 --> 00:44:19,255 then I better go fetch it, okay? So, this is one +那么就获取它，这样处理 858 00:44:19,257 --> 00:44:22,692 thing I've done to increase my performance a little bit. But +能提升一点点性能. 但是 859 00:44:22,694 --> 00:44:24,794 it's still not going to stop things from blocking, +依然没能解决阻塞问题， 860 00:44:24,796 --> 00:44:26,562 because as soon as viewWillAppear happens, +因为当 viewWillAppear 调用时， 861 00:44:26,564 --> 00:44:27,597 and I'm just about to go on screen, +并且视图在屏幕上， 862 00:44:27,599 --> 00:44:30,900 my whole app is going to freeze while I'm out fetching. +整个 app 都被阻塞了，需要去获取数据. 863 00:44:30,902 --> 00:44:32,268 Those big huge images, right? +去获取一张很大的图片. 864 00:44:32,270 --> 00:44:34,437 So I haven't really fixed the problem. I need multithreading +所以我们还没解决这个问题，我需要用到多线程. 865 00:44:34,439 --> 00:44:36,506 for that. But I just wanted to show you to be a little bit +我将会演示如何小心翼翼的 866 00:44:36,508 --> 00:44:40,009 careful about when you fire off an expensive operation. +开启这一昂贵操作的技能. 867 00:44:40,011 --> 00:44:42,178 That's what viewWillAppare, Appear is for. +这也是 viewWillAppear 的作用. 868 00:44:42,180 --> 00:44:44,080 That's really where you wanna fire off things like going +你需要在这里发起所有的操作， 869 00:44:44,082 --> 00:44:48,084 out on the network and stuff, okay? All right, so now let's +例如网络请求什么的. 那么现在就 870 00:44:48,086 --> 00:44:50,620 do our multi guiding and fix this. We're gonna do this here +遵循着多线程规则，来解决阻塞问题吧. 我们需要对 871 00:44:50,622 --> 00:44:53,389 in fetchImage. We're gonna make it so that fetchImage +fetchImage 进行处理. 我们需要使 fetchImage 872 00:44:53,391 --> 00:44:57,126 does the actual fetching in another thread. All right, so +真正的获取事件发生在另一个线程中. 873 00:44:57,128 --> 00:45:00,997 how are we gonna do this? It's pretty simple actually. +那么怎么实现呢？其实很简单. 874 00:45:00,999 --> 00:45:05,968 We're just going to take this code right here which blocks. +只需要将这段代码，这个 block， 875 00:45:05,970 --> 00:45:07,937 This blocks the main queue while it goes out +这个 block 是在主线程进行 876 00:45:07,939 --> 00:45:10,640 on the network, to forget the contents of this URL. +网络请求来获取 url 内容的. 877 00:45:10,642 --> 00:45:13,843 And we're going to use the GCD to +我们使用 GCD 来 878 00:45:13,845 --> 00:45:16,846 put it on a different thread, okay? So I'm just going to +将操作扔到不同的线程中. 所以，代码应该是， 879 00:45:16,848 --> 00:45:21,718 say, dispatch, async, okay? Remember, dispatch async +dispatch_async，记得吗，dispatch_async 880 00:45:21,720 --> 00:45:26,122 takes two arguments. A queue and a block here, a closure or +有两个参数，一个队列和一个 block，即一个闭包或 881 00:45:26,124 --> 00:45:31,194 a function do that. So I'm going to put on one of those, +一个方法. 我准备将处理扔到 882 00:45:31,196 --> 00:45:34,497 concurrent cues. And I'm gonna put it on the one where +并行队列中. 优先级是 883 00:45:34,499 --> 00:45:36,733 the user initiated it but it's not interactive. +user initiated，而不是 interactive. 884 00:45:36,735 --> 00:45:38,634 The user's not in the middle of dragging or something. +因为处理中，用户不会进行拖拽等交互. 885 00:45:38,636 --> 00:45:40,536 They initiated it so it's pretty high priority and +initiated 的优先级已经很高了， 886 00:45:40,538 --> 00:45:45,208 -so I get that by saying dispatc_ge_globa_queue and +so I get that by saying dispatch_get_global_queue and +调用 dispatch_get_global_queue 来获得队列， 887 00:45:45,210 --> 00:45:47,477 the one I want is +这个参数是 888 00:45:47,479 --> 00:45:54,083 -QO_CLASS USE_INITIATED. This one right here, okay? +QOS_CLASS_USE_INITIATED. This one right here, okay? +QOS_CLASS_USE_INITIATED. 第一个参数搞定， 889 00:45:54,085 --> 00:45:58,287 This flags is always zero, right? And now I have this +这个标识直接填 0. 接下来配置 block， 890 00:45:58,289 --> 00:46:00,423 block here, so I'm gonna double-click on that. +双击代码提示， 891 00:46:00,425 --> 00:46:00,957 It's really nice, by the way, +就自动补全了，另外， 892 00:46:00,959 --> 00:46:04,193 you can double-click on these things to expand the block. +除了能双击展开 block 以外， 893 00:46:04,195 --> 00:46:06,829 I'm gonna use the clay trailing, +我使用的的是尾闭包的形式， 894 00:46:06,831 --> 00:46:11,400 closure syntax here. Okay for my block, this block, you'll +完善闭包语法. 这里就是我的 block 了， 895 00:46:11,402 --> 00:46:13,836 notice it takes no arguments, returns no arguments. +你可以看到这个 block 没有参数，也没有返回值. 896 00:46:13,838 --> 00:46:18,941 I'm just going to put all this blocking junk inside here, +然后将这一大段 block 代码，扔到尾闭包中. 897 00:46:18,943 --> 00:46:23,012 okay. So this is going to fix my problem, okay. +这样就能解决我们的问题了. 898 00:46:23,014 --> 00:46:28,217 Except that it probably gonna make my app go all strange +不过这样写可能会导致 app 出现以下莫名其妙的问题， 899 00:46:28,219 --> 00:46:32,155 because I'm gonna be trying to do this inside +因为我在 900 00:46:32,157 --> 00:46:36,459 a non-main queue. All right, cuz this queue, this block +非主队列做了这个操作. 因为这个 block 901 00:46:36,461 --> 00:46:40,329 right here is gonna be put on this queue, and so I can't do +会在这个队列中执行，所以我们不能在 block 里面 902 00:46:40,331 --> 00:46:43,933 this inside of here. Question? >> Can you explain +做这个操作. 什么问题？能讲一下 903 00:46:43,935 --> 00:46:44,867 the trailing, the plot, +尾闭包吗？ 904 00:46:44,869 --> 00:46:47,804 the trailing plot where you added the parenthesis and +应该在哪添加括弧，它是怎样 905 00:46:47,806 --> 00:46:49,438 what it does? >> Yeah, okay, so +执行的？行，好的， 906 00:46:49,440 --> 00:46:55,511 this used to look like this. Okay, so this is normal. +闭包以前是长这样的，这是一个普通的闭包. 907 00:46:55,513 --> 00:46:57,947 I'm calling this function right here, okay? Sorry, +我在调用这个方法时，哦，不好意思， 908 00:46:57,949 --> 00:47:00,750 this function right here. Here is its first arguments, +这个方法. 这是第一个参数， 909 00:47:00,752 --> 00:47:05,388 see that? Here its second argument, okay. +这是第二个参数. 910 00:47:05,390 --> 00:47:09,158 If the sec, if the last argument of any function is +如果第二个参数，如果最后一个参数接收的是 911 00:47:09,160 --> 00:47:14,697 a closure, then you can put it outside of the parenthesis. +闭包，那么就可以将其写在参数列表以外. 912 00:47:14,699 --> 00:47:17,466 -See this dispatc_async parentheses starts here? So +See this dispatch_async parentheses starts here? So +这个 dispatch_async 方法括号从这里开始， 913 00:47:17,468 --> 00:47:20,603 I just took this parentheses off of here and +我只是将这里的反括弧， 914 00:47:20,605 --> 00:47:26,475 I put it over here. Okay, so now this is the first +移到了这里. 所以，现在这里是函数的 915 00:47:26,477 --> 00:47:29,812 argument to this function, inside these parenthesis. And +第一个参数，在参数列表的括号内. 916 00:47:29,814 --> 00:47:33,149 here's the closure which is outside the parenthesis, okay. +而这个闭包，在括号外面. 917 00:47:33,151 --> 00:47:36,185 You definitely wanna get used to that cuz we're almost +这种写法你一定会熟悉的，因为之后我们 918 00:47:36,187 --> 00:47:39,155 always gonna do it that way. And when people design APIs +都会这样写. 当开发者在设计 API 的时候， 919 00:47:39,157 --> 00:47:41,390 they almost always put the closure at the end so +他们尽量将闭包扔到最后，这样 920 00:47:41,392 --> 00:47:44,560 people can do this. All right, so +使用者就可以用尾闭包了. 921 00:47:44,562 --> 00:47:45,595 what am I gonna do about this, +所以我也这样去使用它. 922 00:47:45,597 --> 00:47:49,332 okay? I need this to be back on the main queue. Well, +现在我需要回到主队列. 923 00:47:49,334 --> 00:47:52,902 very simple here. I'm just going to dispatch it back to +非常简单，只需要将它派发回 924 00:47:52,904 --> 00:47:57,707 the main queue. Now, another thing I'm gonna do here, +主队列即可. 除此之外，还有一件事需要处理， 925 00:47:57,709 --> 00:48:02,278 -while I'm kinda at it is, let's get this NS data right +while I'm kinda at it is, let's get this NSData right +先这样，先将这里获取的 NSData 926 00:48:02,280 --> 00:48:06,082 here. I'm gonna assign that to a local variable +使用临时变量接受一下， 927 00:48:06,084 --> 00:48:10,519 here called content of URL, okay? And then I'm gonna put, +叫 contentsOfURL， 928 00:48:10,521 --> 00:48:12,922 so that's gonna be happening in my other queue. +这一部分是发生在另一个队列中的. 929 00:48:12,924 --> 00:48:17,960 And then I'm gonna dispatch async back to the main queue, +然后，调用 dispatch_async 回到主队列， 930 00:48:17,962 --> 00:48:21,597 -which I get by dispatc_ge_mai_queue. +which I get by dispatch_get_main_queue. +传入 dispatch_get_main_queue. 931 00:48:21,599 --> 00:48:24,901 Okay, same exact thing here, okay, here's the block, +这个是一样的，这个 block， 932 00:48:24,903 --> 00:48:28,604 I'm gonna do the same thing. Click trailing, close your +和之前一样. 改为尾闭包， 933 00:48:28,606 --> 00:48:33,376 notation, and now I'm gonna put this inside here, okay. +然后将代码扔进去， 934 00:48:33,378 --> 00:48:37,413 But now the image data is this thing that I got right there, +现在 imageData 应该是这个，我将它放在这， 935 00:48:37,415 --> 00:48:41,317 so that's content of URL. +所以是 contentsOfURL. 936 00:48:41,319 --> 00:48:46,188 Okay, now this happening on the main queue, all is well. +现在，这就在主队列中执行了，全部搞定. 937 00:48:46,190 --> 00:48:50,459 This image=UIImage, the UI kit thing. This is a UI kit thing, +这个 image 是 UIImage，UIKit 中的那个. 这个 UIKit 元素， 938 00:48:50,461 --> 00:48:52,795 by the way, no, not actually because of the UIImage. +准确的说不是严格是，因为它是 UIImage， 939 00:48:52,797 --> 00:48:55,898 That is the one UI thing you can do on a different thread. +而 UIImage 可以在不同的线程中处理， 940 00:48:55,900 --> 00:48:58,367 But it's because when we say image= down here, +这只是进行了图片下载， 941 00:48:58,369 --> 00:49:01,904 it's gonna do something like imageview.image=new value. +因为我们之后要将 image 赋值给 imageView.image. 942 00:49:01,906 --> 00:49:03,439 Okay, well that's the UI kit right there, so +而 UIImageView 是 UIKit 元素，所以 943 00:49:03,441 --> 00:49:06,575 that has to be on the main thread. So that's why I have +必须要在主线程在中处理. 这才是我们要回到主线程的原因. 944 00:49:06,577 --> 00:49:08,878 to do that. Now notice we still have an error here. +注意我们这里还在报错. 945 00:49:08,880 --> 00:49:11,814 Anyone know what this error is? It's pointing right here. +有人知道这个错误原因吗？有人知道吗？ 946 00:49:11,816 --> 00:49:17,987 What do you think it wants there? No idea? +知道编译器想要我们怎么做吗？没人知道？ 947 00:49:21,059 --> 00:49:26,128 It wants self there, because this is a closure. Okay, +它想要加上 self，因为这是一个闭包， 948 00:49:26,130 --> 00:49:27,697 this is inside a closure. And remember, +这段代码在闭包中，记住， 949 00:49:27,699 --> 00:49:32,702 whenever we have a closure and we use a property on our +无论何时，在闭包中访问属性或成员变量， 950 00:49:32,704 --> 00:49:36,472 object, we need to put self in there to make it +都需要使用 self 调用， 951 00:49:36,474 --> 00:49:39,342 clear that we understand this is being captured and +以此指明变量值快照， 952 00:49:39,344 --> 00:49:44,480 kept in the heap. So as long as this closure right here, +并将它存到堆中. 所以，无论是这个闭包， 953 00:49:44,482 --> 00:49:46,749 which it's got this closure inside of it. +还是这个包含在闭包内的闭包， 954 00:49:46,751 --> 00:49:49,385 As long as this is out there fetching, +只要是在函数作用域外了， 955 00:49:49,387 --> 00:49:54,190 it's going to keep this view controller in the heap, okay? +都需要将 view controller 保存在堆上. 956 00:49:54,192 --> 00:49:58,194 Now if we wanted to here, we could do the week self thing +如果我们要在这里使用，还需要用 weak 修饰 self， 957 00:49:58,196 --> 00:50:02,398 and have week self question mark and that way if the image +防止在图片数据回来的时候，self 已经被释放， 958 00:50:02,400 --> 00:50:06,469 came back and our MVC had been thrown out of the heap, +导致 MVC 抛出的堆内存异常. 959 00:50:06,471 --> 00:50:09,405 it would be fine, we would just ignore it. +这样就能避免了，就能忽略掉异常了. 960 00:50:09,407 --> 00:50:11,841 Okay, but I'm pressed for time so I'm not gonna do that but +因为时间原因，我就不演示了， 961 00:50:11,843 --> 00:50:15,277 you could hopefully imagine doing that. Okay, so +不过你们应该能想象出来. 962 00:50:15,279 --> 00:50:17,179 everyone see what we've done here? +每个人都能理解了吗？ 963 00:50:17,181 --> 00:50:20,883 So that's really all we need to do. One thing that it's +这就是我们需要的全部处理. 对了， 964 00:50:20,885 --> 00:50:24,053 a little, now, I told you that multithreading, it's pretty +还有一小点，现在我讲解了多线程， 965 00:50:24,055 --> 00:50:26,522 easy to read this code and understand what's going on. +非常简单，一看代码就能明白. 966 00:50:26,524 --> 00:50:29,725 But you've got to think of the bigger picture of what's +但是你想想，如果是在用多线程 967 00:50:29,727 --> 00:50:32,962 happening with multithreading here. For example, +加载一张很大的图片呢，会怎样. 比如， 968 00:50:32,964 --> 00:50:37,500 what happens in Cassini if I click on the Cassini, +在点击 Cassini 按钮时，Cassini 会怎样， 969 00:50:37,502 --> 00:50:40,236 which is a kind of a small image, and +这还是张小图， 970 00:50:40,238 --> 00:50:43,305 then I change my mind and click on Earth. +如果我临时改变主意，点击了 Earch. 971 00:50:43,307 --> 00:50:48,377 Okay, so Cassini, which is small, comes back, okay? +现在，Cassini 这张小图加载完成， 972 00:50:48,379 --> 00:50:51,280 This code is gonna put Cassini on screen. But then the Earth +那么 Cassini 就会渲染在界面上，这时候，Earth 973 00:50:51,282 --> 00:50:53,883 is gonna come back and this code's gonna put the Earth on +加载完了，Earth 就会覆盖在 Cassini 上， 974 00:50:53,885 --> 00:50:55,951 top of it, okay? So I'm gonna get this flashing thing, +所以就会导致 Cassini 图片闪一下， 975 00:50:55,953 --> 00:50:58,788 Cassini, Earth. Or worse, if I clicked Earth first and +接着显示 Earth. 更糟的是，如果我先点击的 Earth， 976 00:50:58,790 --> 00:51:01,057 then clicked Cassini, it would show Cassini and +之后再点击 Cassini，万一先展示 Cassini， 977 00:51:01,059 --> 00:51:03,359 then later Earth would come in and it would be showing Earth, +之后再展示 Earth，然后 Earth 就是最终渲染的图片， 978 00:51:03,361 --> 00:51:04,693 even though I clicked on Cassini. +即使我最后点击的是 Cassini. 979 00:51:04,695 --> 00:51:07,830 Okay, do you see the problem, is that I'm firing off these +能明白这个问题吗？我在不同的线程中， 980 00:51:07,832 --> 00:51:09,265 network things in other threads. +发起的网络请求， 981 00:51:09,267 --> 00:51:11,767 They're coming back at different times. So +他们的响应时间可能会不同. 982 00:51:11,769 --> 00:51:12,435 really I want to, +所以， 983 00:51:12,437 --> 00:51:14,870 If I'm gonna be a good programmer here, +如果我是一个优秀的开发者， 984 00:51:14,872 --> 00:51:16,172 multithreaded, I need to check and +在多线程中，我需要检查响应的 985 00:51:16,174 --> 00:51:19,208 make sure that the URL that I'm fetching, +URL，是否是我之前获取的那个， 986 00:51:19,210 --> 00:51:24,480 that's this URL right here, is still equal to the image URL +即这个 URL，是否匹配这个 imageURL. 987 00:51:24,482 --> 00:51:29,618 that I ask for. Okay, then I'll do this. If it's not, +如果匹配，才赋值. 如果不匹配， 988 00:51:29,620 --> 00:51:34,156 then maybe I could print something like ignored data +那么就输出 ignore data， 989 00:51:34,158 --> 00:51:39,061 returned from URL, and then we'll put the URL in here, +returned from URL，然后将 url 拼在后面. 990 00:51:39,063 --> 00:51:43,232 okay? And that needs self here, of course, cuz that's +这里也需要加上 self，毕竟 991 00:51:43,234 --> 00:51:47,002 inside this closure as well, all right? Everybody got that? +这也是在闭包中. 都懂了吗？ 992 00:51:47,004 --> 00:51:50,439 So let's go ahead and run, see if this works. So +那我们来运行下，看看效果. 993 00:51:50,441 --> 00:51:54,110 what we should have now is a very responsive UI, okay, +所以，现在拿到的是一个丝滑的 UI， 994 00:51:54,112 --> 00:51:56,412 all the time, no matter what we click on, so let's try it. +整个程序都是，无论是点击哪个按钮，试试， 995 00:51:56,414 --> 00:51:59,482 Earth, Cassini, see I'm able to click on different things. +Earth，Cassini，看见了吗，都没有被阻塞. 996 00:51:59,484 --> 00:52:04,587 I can still rotate, okay. Whoops, wrong way around. And, +还可以进行旋转. 噢喔...旋转方式错了. 997 00:52:04,589 --> 00:52:09,125 the it's gonna pick whichever the last one that I asked for. +无论我最后请求的是哪个， 998 00:52:09,127 --> 00:52:11,060 It's still fetching right here. It's gonna eventually, +都会获取到争取的图片. 最终， 999 00:52:11,062 --> 00:52:17,633 hopefully, get one. And maybe it's even easier to see this, +都会获取到一张. 可能要等会才能请求完， 1000 00:52:17,635 --> 00:52:20,402 maybe. Let's stop this action, go look on our iPhone, cuz you +停止这个程序，重新跑在 iPhone 上看看， 1001 00:52:20,404 --> 00:52:23,172 can really see it happening on iPhone because when we click +因为这个过程在 iPhone 上更清晰， 1002 00:52:23,174 --> 00:52:26,142 on them, it actually segues and comes back. +它会有视图的转场效果. 1003 00:52:26,144 --> 00:52:31,881 So watch this. Are we running here? +来看看. 跑起来了吗？ 1004 00:52:31,883 --> 00:52:37,887 Oops, no, we want iPhone. +哦，不对，我们需要的是 iPhone. 1005 00:52:40,491 --> 00:52:43,759 Okay, so we go back here. Now I click Cassini, +好了，回到这个界面，点击 Cassini， 1006 00:52:43,761 --> 00:52:46,228 it's loading it, but I can go back, okay. +程序正在加载，这时我点击返回， 1007 00:52:46,230 --> 00:52:48,197 While this is still loading, I can go back and +但其实加载还在继续， 1008 00:52:48,199 --> 00:52:51,634 change my mind because my UI is highly responsive, +我能临时改变主意，能点击返回，因为 UI 并未被阻塞， 1009 00:52:51,636 --> 00:52:53,636 even though it's loading those things in the background. +即使图片在后台加载. 1010 00:52:53,638 --> 00:52:56,705 From 0f22eef13632256b3f79e80db533dbf657e56b92 Mon Sep 17 00:00:00 2001 From: Cwift <535967481@qq.com> Date: Tue, 6 Dec 2016 10:22:14 +0800 Subject: [PATCH 17/23] =?UTF-8?q?=E7=AC=AC=E4=BA=94=E7=AB=A00-500=20(#52)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 第五集 0-500 --- .DS_Store | Bin 0 -> 6148 bytes subtitles/.DS_Store | Bin 0 -> 8196 bytes ...ontroller, Gestures, and Multiple MVCs.srt | 502 +++++++++++++++++- 3 files changed, 501 insertions(+), 1 deletion(-) create mode 100644 .DS_Store create mode 100644 subtitles/.DS_Store diff --git a/.DS_Store b/.DS_Store new file mode 100644 index 0000000000000000000000000000000000000000..5b41c0c4316bdea87bf038b1c5a667af5d039779 GIT binary patch literal 6148 zcmeHKPjAyO6o2kINY_gcAWh=pBS;l0?O@lebVwW~RSVjL7%B;gsHG5BO}YqGm2&3J z7vTT*Kycy<@KHFG_iT4s$habe{G#XI^NW9W^K%;80Kf+G=njAj01i4~qlLuDVj$;fl%4pxzhe>Qld*e!G>cD>IttSGNMs@uiO63$ExN|;_F~cR z^*g+`(_41F-=9(RA!DCOw%#XO*_wEsZrB`nZpM&BQtYCVQO^j zpR4A;JdL)r3RnfI3T)`AOY8sspU?kQlC4<W@v7~9fPyp665^PB=i&tRz$GiY`rpk%OxRp75G@C&(Lin#y) literal 0 HcmV?d00001 diff --git a/subtitles/.DS_Store b/subtitles/.DS_Store new file mode 100644 index 0000000000000000000000000000000000000000..1159ffb997b1ef207e44679b10e63153eabf5a30 GIT binary patch literal 8196 zcmeHM&2AGh5FSGhmEb^&gnB_Thyx&0DF58jG%YGLv?5i-k^ZD5B2A)ALfcy&gNNb) zcm&=8zHjW!dehyA140$pl6Smo&&=m<#@=`%BBnY#SQ1$fky%vAYgce7DC}oFS1$P{ z^NWvnuaSYsz?9i(Tn(2kjP-Y-QC}7clUsW z%Xba+?oTafiOd1tqcOrnzb@2(W`J63;Ttx9*}%dLSjgs>w_v3Pi^srOXv@5xur&`$ zj}^@_X3rUK0LK|5?}}}FpRjQgHlC=BcVKE8Y#aka0>)B~mcb{Va+Z$WLd)dJoCY(! z1Lg*rgH120YV6s;3RCT}IpOBa_jSm^-2 zmAdSJ?@}wd)pp-!CNsn3NVZjzfzKWM4C((oQ*FOX_$9s2t|7T||{FcnU^Wytof3j(c{*&+jUwz{-&j0`b literal 0 HcmV?d00001 diff --git a/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt b/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt index 99b803b..f484599 100755 --- a/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt +++ b/subtitles/5. Interface Builder, FaceView Controller, Gestures, and Multiple MVCs.srt @@ -1,1998 +1,2497 @@ -1 +1 00:00:00,001 --> 00:00:03,836 [MUSIC] +[MUSIC] 2 00:00:03,838 --> 00:00:06,305 Stanford University. >> All right, +斯坦福大学. >> 好的, 3 00:00:06,307 --> 00:00:12,177 well then welcome to lecture 5, of CS193P, +欢迎来到 CS193P 的第五课， 4 00:00:12,179 --> 00:00:16,015 this is the spring of 2016. And +现在是 2016 年春。 5 00:00:16,017 --> 00:00:21,420 today we are going to, first, work a little more and +今天我们首先要做的是在之前的工程中增加一点功能，然后 6 00:00:21,422 --> 00:00:24,957 face it. I'm gonna show you a little kind of some cool +看看效果。 我将会为你展示一些 Xcode 可视化界面中 7 00:00:24,959 --> 00:00:27,359 features in the interface builder part of Xcode, +很酷的特性， 8 00:00:27,361 --> 00:00:30,662 that's the part where we're building our storyboard. +这部分内容我们会在 Storyboard 上完成。 9 00:00:30,931 --> 00:00:34,033 Then we're gonna start talking about what FACEIT's +然后我们将开始讨论如何正确实现 FACEIT 中的 10 00:00:34,035 --> 00:00:36,802 view controllers model really should be. +视图、控制器和模型。 11 00:00:36,804 --> 00:00:39,638 Okay, cuz right now if you look at the code in our +好的, 现在如果你看了 FACEIT 中 12 00:00:39,640 --> 00:00:42,307 controller of our MVC for FACEIT. It's blank, +控制器的代码。 你会发现它是空白的， 13 00:00:42,309 --> 00:00:44,743 there's nothing in there. So we need to do some work there. +什么都没有。我们需要在上面完成一些工作。 14 00:00:44,745 --> 00:00:48,113 Now we're gonna come back to the slides and I'm gonna talk +现在先回到幻灯片上来 15 00:00:48,115 --> 00:00:51,283 about gestures, okay which is the input side of UIView. +我要讲解手势的相关知识点, 它是 UIView 的输入端。 16 00:00:51,285 --> 00:00:54,453 And I'll do a demo where we put some gestures in FACEIT. +我会演示一个在 FACEIT 上添加手势的 Demo。 17 00:00:54,455 --> 00:00:57,456 And then time permitting I'm gonna end with some more +然后如果时间允许的话， 18 00:00:57,458 --> 00:01:00,225 slides starting to talk about multiple MVCs which is +我会在幻灯片上讲解多重 MVC 19 00:01:00,227 --> 00:01:04,229 the gateway to building bigger applications. Okay, so that's +它是构建更大型的应用的入口。 好吧 20 00:01:04,231 --> 00:01:07,499 what's on tap for today. So let's dive right into the demo +以上就是今天的主要内容。 让我们直接进入 demo 环节 21 00:01:07,501 --> 00:01:10,702 here. I'm gonna do these two things I talked about, +我要开始做我刚刚谈到的那两件事, 22 00:01:10,704 --> 00:01:15,941 which is the Interface Builder. And a model for +一个是界面生成器。 另一个是 23 00:01:15,943 --> 00:01:16,508 our FaceViewController, +我们的 FaceViewController 的模型， 24 00:01:16,510 --> 00:01:18,243 which is gonna be a facial expression, +正常来说这个模型要描述一个面部表情。 25 00:01:18,245 --> 00:01:22,548 not surprisingly. All right, so here we are in FaceView, +好的，现在我们来到 FaceView， 26 00:01:22,550 --> 00:01:26,285 this is where we left off last time. I'm gonna quickly +这是我们上节课最后停留的部分。 27 00:01:26,287 --> 00:01:29,855 enhance our FaceView to be a little cooler right now if you +我会快速地强化 FaceView 的功能，让它变得更酷。 28 00:01:29,857 --> 00:01:33,559 remember from last time our FaceView has a mouth which we +如果你还记得上一次我们对 FaceView 上的嘴巴 29 00:01:33,561 --> 00:01:37,029 can configure a little bit. We can make it smile and +进行了一些配置。 我们可以让它微笑、 30 00:01:37,031 --> 00:01:40,466 frown and then it has two eyes, okay. And I'm gonna add +皱眉并且拥有两只眼睛，很不错。我现在要增加两样东西， 31 00:01:40,468 --> 00:01:43,368 two things, one I'm gonna make it so he can close those eyes. +首先我可以让它闭上眼睛。 32 00:01:43,370 --> 00:01:46,505 And another thing I'm gonna do is, I'm gonna add eyebrows. +我要做的另外一件事是:给它加上眉毛。 33 00:01:46,507 --> 00:01:49,208 Okay, now I'm gonna do this really fast because the code +我完成起来非常地快， 34 00:01:49,210 --> 00:01:51,577 that it takes me to do this really wouldn't learn that +因为我所需要的代码不需要对现有的的代码做较大改动， 35 00:01:51,579 --> 00:01:53,879 much from going through it, but it's pretty just more, +只需要新增一些代码， 36 00:01:53,881 --> 00:01:56,081 pretty much more of the same of the stuff women doing. +跟女人画眉毛相比要省事得多。 37 00:01:56,083 --> 00:02:01,120 So I'm gonna add a couple of more public vars because +因此我需要定义一组新的公有变量， 38 00:02:01,122 --> 00:02:03,122 these are gonna be configurable thing. One is +因为有一些东西需要可配置。 39 00:02:03,124 --> 00:02:06,758 whether the eyes are open, which is gonna be a bull. And +一个属性表示眼睛是否是睁开的, 这是一个布尔变量。 40 00:02:06,760 --> 00:02:10,462 I'm gonna say these are gonna start out open, okay? +我将把眼睛的初始状态设置为睁开，怎么样？ 41 00:02:10,464 --> 00:02:13,398 So it's just gonna be the default. And then I'm also +true 是它的默认值。 然后我定义另一个新属性 42 00:02:13,400 --> 00:02:16,568 going to have something called eyebrowTilt, okay? +取名为 eyebrowTilt, 怎么样? 43 00:02:16,570 --> 00:02:20,272 Which is gonna be a double. And I'm gonna start it at 0.0. +这是一个 double 类型的变量. 初始值设置为 0.0。 44 00:02:20,274 --> 00:02:23,575 It's similar to the kind of the mouth curvature. So +它的定义类比于嘴巴弯曲的弧度。 45 00:02:23,577 --> 00:02:26,979 we're gonna have -1 be full furrow. +我们让默认曲率为 0。 46 00:02:26,981 --> 00:02:31,016 And one will be fully relaxed eyebrows, okay? +-1代表很郁闷，1代表完全放松的眉毛, 怎么样? 47 00:02:31,018 --> 00:02:35,187 So similar kind of thing as we had for the mouth curvature. +非常像我们对嘴巴的曲率做的设置。 48 00:02:35,189 --> 00:02:38,190 So let's do the eyes open first. Quite simple. +先来让眼睛睁开。很简单。 49 00:02:38,192 --> 00:02:42,094 In path for eye right now. You can see that we use a path for +在之前画眼睛的路径中， 你可以看到我们用一个圆的路径代表眼睛。 50 00:02:42,096 --> 00:02:44,429 circle, so that's why our eyes are circular. So +这解释了为什么眼睛是圆的。 51 00:02:44,431 --> 00:02:48,800 if my eyes are open, I'm just gonna continue to do that, +所以如果眼睛睁开的话， 我打算还这么做， 52 00:02:48,802 --> 00:02:50,035 okay? We'll do to pass the circle. +如何? 我们继续用圆来表示。 53 00:02:50,037 --> 00:02:54,206 But if the eyes are closed, then instead what I'm gonna do +但是如果眼睛是闭上的, 我会用另一个图形来表示 54 00:02:54,208 --> 00:02:58,877 is do this, which is basically use a line. +只使用一条线。 55 00:02:58,879 --> 00:03:00,546 So I'm just gonna draw a horizontal line, +如果眼睛是闭合的话我会画一条水平的线。 56 00:03:00,548 --> 00:03:03,815 if the eyes are closed. Okay? Very simple. Here, BezierPath, +非常简单。看这里， BezierPath， 57 00:03:03,817 --> 00:03:07,786 move to a point, draw a line. Okay? And then for the brows, +移动到一个点上,画一条线。然后画眉毛， 58 00:03:07,788 --> 00:03:10,422 you see, you know we have path for eye, we have path for +如你所见，我们有眼睛的路径， 59 00:03:10,424 --> 00:03:15,093 mouth, so I'm just gonna make a path for brows. Which I +有嘴巴的路径，所以我仅仅需要为眉毛画一个路径 60 00:03:15,095 --> 00:03:19,198 think I have here, yes. So here's our path for brow and +我想我可以用这里的代码！现在这就是我们的眉毛的路径 61 00:03:19,200 --> 00:03:22,167 it's pretty straightforward. It's just drawing a line but +它很简单. 画了一条直线 62 00:03:22,169 --> 00:03:28,207 this line is tilted. Depending on how much tilt we want. +这条线是倾斜的。 倾斜程度取决于我们设置的斜率 63 00:03:28,209 --> 00:03:32,077 And of course we need a little func a little static here to +当然了我们还需要向比例中增加一些静态变量 64 00:03:32,079 --> 00:03:36,815 go up in our ratios. Which is the relative position of +代表眉毛相对于旋转中心点的偏移距离 65 00:03:36,817 --> 00:03:40,285 the brow to the scroll radius, just like we have all these +就像我们设置的 66 00:03:40,287 --> 00:03:44,089 other things that are relative to the radius. Okay? And +其他与半径相关的信息。 67 00:03:44,091 --> 00:03:46,892 now that we have pathForBrow, just like we did with +现在我们有了方法 pathForBrow, 就像定义 68 00:03:46,894 --> 00:03:48,594 pathForEye and pathForMouth, we'll go ahead and +pathForEye 和 pathForMouth 那样， 让我们继续 69 00:03:48,596 --> 00:03:52,831 stroke those. So I'll say pathFor, Brow, the left one, +绘制它们。 我要绘制的路径是, 眉毛, 左边那条, 70 00:03:52,833 --> 00:03:58,270 stroke, and then we'll do a pathForBrow, the right one, +绘制, 然后绘制右边的眉毛。 71 00:03:58,272 --> 00:04:01,073 and stroke. Okay? +大功告成。 72 00:04:01,075 --> 00:04:03,408 So let's go ahead and run, see what we'll look, +让我们继续并且运行程序, 看看我们能看到什么, 73 00:04:03,410 --> 00:04:08,280 we should have eyebrows now. Okay, +现在我们应该有眉毛了。 好的, 74 00:04:08,282 --> 00:04:10,949 yeah, look we got eyebrows, they're kinda cute. And +耶, 看我们有眉毛了, 它们有一点可爱。 75 00:04:10,951 --> 00:04:12,384 we should also be able to close the eyes. +我们应该也可以让眼睛闭上了。 76 00:04:12,386 --> 00:04:16,421 So I'm gonna change this eyesOpen to false. +所以我要把 eyesOpen 设为 false。 77 00:04:18,559 --> 00:04:22,494 See if that works, it does, eyes closed. +看下有没有起作用,起作用了, 眼睛闭上了。 78 00:04:22,496 --> 00:04:26,298 We could set our eyebrowTilt maybe to I don't know -0.5. +我们可以把 eyebrowTilt 设置成..嗯..就-0.5吧。 79 00:04:26,300 --> 00:04:33,538 See what that does. Okay, +看下效果。好的, 80 00:04:33,540 --> 00:04:36,775 we have some tilt there. Okay, so you can see with eyebrows, +增加了倾斜的效果. 所以你看到了眉毛的效果, 81 00:04:36,777 --> 00:04:38,510 we can make more facial expressions. +我们可以做出更多的面部表情。 82 00:04:38,512 --> 00:04:39,011 That's why I put him in there. +这就是我把他放在这的原因。 83 00:04:39,013 --> 00:04:42,247 So we'd have a little more room to maneuver when it +当涉及到面部表情时 84 00:04:42,249 --> 00:04:43,048 comes to facial expressions. +我们有更多可操作的选项。 85 00:04:43,050 --> 00:04:46,318 I'm gonna do a couple other things here. One is, there's +我要在这设置更多的选项。 其中一个可以是 86 00:04:46,320 --> 00:04:51,290 some constants I have in here like my face is always blue. +我在这里定义的一些常量，比如颜色总是蓝色的。 87 00:04:51,292 --> 00:04:53,959 I don't really want that. So I'm gonna make that be a var, +我不希望这样。 所以我把它改成一个变量, 88 00:04:53,961 --> 00:04:57,029 so I'm gonna call it color. So I'm gonna go up here and +我准备给变量取名为 color。 我在这里定义一个变量 Color 89 00:04:57,031 --> 00:05:01,967 make a var. Color, which is gonna be a UIColor. +它的类型是 UIColor。 90 00:05:01,969 --> 00:05:06,371 And I'm gonna let it be blue by default. Whoops UIColor, +并且我设置它的默认值是蓝色。 唔 UIColor, 91 00:05:06,373 --> 00:05:10,909 blueColor by default. And I'm also gonna do a var for +默认是 blueColor。然后我也会把线的宽度定义为一个变量 92 00:05:10,911 --> 00:05:14,579 the linewidth, okay? Currently, our linewidth is +怎么样? 现在, 我们的线宽一直是 0.5 93 00:05:14,581 --> 00:05:18,617 always 5.0, but I'm gonna, and we'll make the default 5.0. +所以我把默认值设成 5.0. 94 00:05:18,619 --> 00:05:22,454 But I'm gonna change all those 5.0s with this var, so let's +但是我会把所有用到 5.0 这个常量的地方替换成这个变量, 95 00:05:22,456 --> 00:05:28,994 do that. There's 1, 2, 3, 4. Okay, that's our four things. +让我们完成这个工作。 一共有 1, 2, 3, 4. 好的, 我们替换了四处. 96 00:05:28,996 --> 00:05:33,298 Eyebrows, eyes, our mouth, and the skull. Okay? So now we've +眉毛, 眼睛, 我们的嘴, 和骨头. okay? 97 00:05:33,300 --> 00:05:37,402 kind of made our faceView quite externally usable, okay. +我们增强了 faceView 的外部调用性, 好的。 98 00:05:37,404 --> 00:05:40,772 All these public functions are something that a controller +所有这些公开的方法都是一个控制器 99 00:05:40,774 --> 00:05:44,443 is likely to use. Because we're part of the view, okay. +可能用到的。 因为我们都是视图的一部分, okay. 100 00:05:44,445 --> 00:05:48,280 We're a generic face-drawing view, and so we can be used by +我们是一个通用的脸部绘制视图, 所以我们可以被 101 00:05:48,282 --> 00:05:52,084 any controller that might want to draw a face. Okay? Which is +任何想要绘制面部的控制器所使用。 Okay? 102 00:05:52,086 --> 00:05:53,985 the kind of controller we happen to have now. +哪一个是我们已经拥有了的控制器呢？ 103 00:05:53,987 --> 00:05:54,619 It's drawing a face. But +这里绘制了一张脸。 不过 104 00:05:54,621 --> 00:05:57,222 if we look at our controller right here, it's drawing +如果我们查看这里我们自己的控制器的话, 105 00:05:57,224 --> 00:06:01,326 a face but doesn't really control that face much, okay? +控制器绘制一张脸但是对这张脸做任何配置, okay? 106 00:06:01,328 --> 00:06:04,563 It has a view that it has in its storyboard, where we put +它拥有了 storyboard 提供的视图, 107 00:06:04,565 --> 00:06:08,667 our face right here, but it's not really doing much. And +我们要把脸绘制在上面, 但是没有做其他的工作。 108 00:06:08,669 --> 00:06:12,037 we'll fix that in a minute. Now, one thing that's kind of +我们一分钟就能完成。 现在， 有一件令人苦恼的事情， 109 00:06:12,039 --> 00:06:15,140 annoying is if we look in our storyboard right here. +当我们查看我们的 storyboard。 110 00:06:15,142 --> 00:06:16,341 Okay, here's our storyboard right there. +Okay, 这里是我们的 storyboard。 111 00:06:16,343 --> 00:06:20,312 We don't see that face and okay we only have one +我们看不到我们绘制的脸，并且我们只有一个 MVC 112 00:06:20,314 --> 00:06:23,682 MVC here we know it's a face and the fact that it +我们知道它是一个脸，可是 113 00:06:23,684 --> 00:06:24,850 doesn't show up there,eh. But +我们看不到。但是 114 00:06:24,852 --> 00:06:27,886 what if we had like 20 view controllers and this is just, +如果我们有 20 个控制器, 115 00:06:27,888 --> 00:06:29,755 this was the face but there's a whole bunch of other ones. +这里会有一张脸，那里又会有一整套别的东西。 116 00:06:29,757 --> 00:06:32,958 Would be really cool if that face would show up here. Okay. +如果脸能在这里展示出来，岂不是很酷？ Okay。 117 00:06:32,960 --> 00:06:34,626 So we can see it in interface build. And in fact, +等下我们会在可视化构造器上看到它。 实际上， 118 00:06:34,628 --> 00:06:38,330 that's really easy to do. All you do is you go to your view, +很容易办到。你需要做的就是到你的视图上, 119 00:06:38,332 --> 00:06:41,366 okay? Your custom UIView, faceView. And you just put +okay? 你自定一个 UIView, 取名 faceView.并且它的定义上面加上 120 00:06:41,368 --> 00:06:46,638 @IBdesignable at the front. And if you say @IBdesignable, +@IBdesignable 关键字。 如果你声明了 @IBdesignable, 121 00:06:46,640 --> 00:06:51,676 then interface's builder is automatically going to assume, +可视化构造器会认为你想要 122 00:06:51,678 --> 00:06:52,711 you want me to draw this thing. +绘制这个东西。 123 00:06:52,713 --> 00:06:54,579 So you can see, it's even compiling it and drawing it. +所以你可以看到, 代码会被编译并且绘制。 124 00:06:54,581 --> 00:06:59,684 So now it appears, here in my storyboard, okay. So that's +在我的 storyboard 上，脸出现了。 okay。 125 00:06:59,686 --> 00:07:02,154 pretty cool. But one thing that's not so cool is, if I +这真的很酷。但是还有一件不太酷的事情， 126 00:07:02,156 --> 00:07:05,724 click on my faceView and bring up the inspector. I can only +如果我点击我的 faceView 并且打开检查器。 127 00:07:05,726 --> 00:07:08,593 inspect the attributes about my faceView that inherits from +我只能检查 faceView 从 View 继承来的属性 128 00:07:08,595 --> 00:07:11,663 view like its background color and things like that, right? +比如像它的背景色这样的属性, 没错吧? 129 00:07:11,665 --> 00:07:15,133 It'd be really cool if I could inspect things like eyebrow +如果我能检查像眉毛、最的曲率 130 00:07:15,135 --> 00:07:15,500 mouth curvature and the color and the scale. Wouldn't it be +以及颜色和比例的话那就很酷了。 131 00:07:15,502 --> 00:07:18,770 tilt and +这里是不是该倾斜 132 00:07:18,772 --> 00:07:20,572 cool if I could do all that in interface builder so +如果我能在可视化构造器中完成所有这些属性的设置那就太酷了。 133 00:07:20,574 --> 00:07:23,842 I could set up the face how I want it to initially look +也许我可以按照我的想法来初始化一张脸， 134 00:07:23,844 --> 00:07:27,245 maybe, interface builder and you can do that too. +可视化构造器可以实现。 135 00:07:27,247 --> 00:07:28,313 If you go back to faceView. +如果你回顾 faceView. 136 00:07:28,315 --> 00:07:33,151 All of these things that are right here, that are settable, +所有的这一切都在这里, 它们是可设置的, 137 00:07:33,153 --> 00:07:37,022 you can just put in front of them @IBInspectable. +你只需在它们前面加上 @IBInspectable。 138 00:07:37,024 --> 00:07:38,957 Okay, which means they will show up in the inspector. +Okay, 这代表该属性会被显示在观察器中。 139 00:07:38,959 --> 00:07:42,561 And so I am gonna make all of these things be inspectable, +因此我把所有的这些属性都设置为可观察的， 140 00:07:42,563 --> 00:07:47,432 put inspectable on all these guys. Okay. Could go into +给这些家伙们都加上 inspectable。 Okay. 现在可以回到 141 00:07:47,434 --> 00:07:50,068 interface builder. But if I go here and bring out my +可视化构造器中了。 你打开这里 142 00:07:50,070 --> 00:07:53,238 utilities now you can see I've still got all the view stuff. +你依旧能看到所有 View 相关的属性。 143 00:07:53,240 --> 00:07:55,774 But now I've got all these faceView things, so +但是现在我们拥有 faceView 中的东西了， 所以 144 00:07:55,776 --> 00:07:59,010 I can set my scale to 0.05. Okay, and that makes it small. +我可以把比例设置为 0.5. Okay, 这使得人脸变小了。 145 00:07:59,012 --> 00:08:02,814 Or I could set my color to orange. Okay, +或者我可以把颜色设置成橘黄色。 Okay, 146 00:08:02,816 --> 00:08:05,383 San Francisco Giants color, all right! I can make my line +洛杉矶巨人队的颜色。好吧! 我可以把线宽从5改为2 147 00:08:05,385 --> 00:08:09,254 width B2 instead of 5, where it's a little thinner, okay? +线就变细了， okay? 148 00:08:09,256 --> 00:08:13,925 I could set my mouth curvature in here, let's say -0.5. +在这里我可以设置嘴巴的曲率, 设置为 -0.5。 149 00:08:13,927 --> 00:08:18,196 All right, eyes open? On? +对把, 眼睛是否睁开? 睁开状态? 150 00:08:18,198 --> 00:08:22,234 There we go, okay, see that? 3.9 again. +让我们继续, okay,看到了吗? 比例变回0.9。 151 00:08:22,236 --> 00:08:25,103 All right, so that's kinda cool that we can do that. +好的, 我们做到了，这很酷。 152 00:08:25,105 --> 00:08:27,372 And, in fact, when we first run our application, +实际上， 当我们第一次运行程序, 153 00:08:27,374 --> 00:08:30,842 it will use these values. So let's go ahead and run and +它就会应用这些值。 让我们继续并且运行程序 154 00:08:30,844 --> 00:08:32,711 you're gonna see it's gonna keep this exact face. +你会看到屏幕上会显示相同的脸。 155 00:08:32,713 --> 00:08:35,981 Line, the color, the line thickness, all these things. +线条、颜色、线宽以及所有的这些属性。 156 00:08:35,983 --> 00:08:38,316 Just like if we had set any other attribute over here, +就像我们在检查器上设置的任何其他属性一样。 157 00:08:38,318 --> 00:08:40,819 background color or something like that. When we run, +比如背景颜色或者其他诸如此类的属性。 当然，当我们运行时 158 00:08:40,821 --> 00:08:43,889 of course, those would be the things it starts out with, +这些属性都会被初始化, 159 00:08:43,891 --> 00:08:46,758 okay? Now, one little thing to watch out for +okay? 现在， 有个小细节要注意 160 00:08:46,760 --> 00:08:50,428 when you're doing this, is [COUGH] these IBInspectable +当你要设置可变属性为 IBInspectable 时 161 00:08:50,430 --> 00:08:54,232 vars, you have to explicitly type them. You see, there, +你必须显式地声明它们的类型。 你看，像这里， 162 00:08:54,234 --> 00:08:56,434 most of these I wouldn't even need to type, right? +大部分我原本都不需要声明类型的, 对吧? 163 00:08:56,436 --> 00:09:00,071 Swift could infer that that's a double from there. But +Swift 可以通过赋值推断出 Double 类型。 但是 164 00:09:00,073 --> 00:09:00,906 if you're using the IBInspectable, +如果你正在使用 IBInspectable, 165 00:09:00,908 --> 00:09:03,975 you have to explicitly type, basically interface builder +你必须显式地写出类型， 因为可视化构造器不能推断它们的类型。 166 00:09:03,977 --> 00:09:07,379 can't infer it, Swift can, but interface builder can't. +Swift 可以，但是可视化构造器不能。 167 00:09:07,381 --> 00:09:09,748 So you need to make those explicit, okay. +所以你需要明确类型， okay。 168 00:09:09,750 --> 00:09:14,786 Just a minor deal there. Okay, now, one other thing I wanna +这只是一个小的需要注意的点。 Okay, 现在，另外一件我要说到的事情是 169 00:09:14,788 --> 00:09:19,224 talk about here with a view is if somebody sets the scale to +这里的视图，如果某个人设置了它的比例， 170 00:09:19,226 --> 00:09:22,093 something, okay, in the code. Like let's say our +okay, 在代码里面设置的。 171 00:09:22,095 --> 00:09:24,696 controller over here, let's say we have some code in here +控制器在这里, 我们在视图的代码中设置比例。 172 00:09:24,698 --> 00:09:29,100 to set the face view scale. It would actually do nothing. +实际上没有起到任何效果。 173 00:09:29,102 --> 00:09:32,404 Okay, nothing would change on screen, and why is that? +Okay,屏幕上不会有变化， 这是为什么呢? 174 00:09:32,406 --> 00:09:35,373 Well because when you set this scale to be 0.5, +因为当我们把比例设置为 0.5 时, 175 00:09:35,375 --> 00:09:39,511 all you did was set this var, you didn't do anything else, +你所做的只是修改了这个变量, 你没有做其他的事情, 176 00:09:39,513 --> 00:09:41,379 okay? So that var is set to 0.5 and +okay? 因此当变量变为 0.5 177 00:09:41,381 --> 00:09:44,616 if the face were to redraw, it would redraw smaller but +人脸的视图进行重绘, 它会被绘制的更小 178 00:09:44,618 --> 00:09:49,020 nothing is causing the face to redraw. So any time you have +但是重绘的事件没有被触发。 所以任何时候 179 00:09:49,022 --> 00:09:53,625 these public vars that you allow to be set, you need to +你允许这些公共的变量可以被修改的时候, 180 00:09:53,627 --> 00:09:57,562 make it so that when they change, the viewer redraws. +你需要在属性改变时重绘视图。 181 00:09:57,564 --> 00:10:00,298 Okay, now how are we gonna do that? Well we're gonna do that +Okay, 现在我们该怎么做? 我们用之前讲到的属性观察器 182 00:10:00,300 --> 00:10:03,935 using these property observers we talked about before. +来实现这个功能。 183 00:10:03,937 --> 00:10:07,172 Remember, the dil, didSet and the willSet? These are little +还记得 didSet 和 willSet 吗? 它们都是一小段代码 184 00:10:07,174 --> 00:10:10,475 pieces of code that get executed whenever this, +这种情况下每当变量被赋值或者访问的时候就会触发, 185 00:10:10,477 --> 00:10:15,246 in this case get set, okay? So if this got set to something +okay? 因此如果该变量被赋值 186 00:10:15,248 --> 00:10:19,117 then in didSet, I wanna re-draw, and how do I re-draw? +然后会进入 didSet 代码段, 我想要重绘, 那么我该如何重绘? 187 00:10:19,119 --> 00:10:24,756 Maybe I say self.drawRect do I do that? No, +也许我需要调用 self.drawRect 我要这么做吗? 不, 188 00:10:24,758 --> 00:10:27,926 I would fail this class if I did that cuz we never call +在类中这样做会失败， 因为我们永远都不能调用 189 00:10:27,928 --> 00:10:32,831 drawRect. We say instead setNeedsDisplay, okay, +drawRect。 我们说过使用 setNeedsDisplay 替代， okay， 190 00:10:32,833 --> 00:10:38,169 setNeedsDisplay is how we tell the system, please I need to +setNeedsDisplay 的作用是我们告诉系统， 我需要被重绘，谢谢。 191 00:10:38,171 --> 00:10:42,207 be redrawn, okay. And it will happen sometime in the future, +okay。 重绘会在未来的某个时刻执行, 192 00:10:42,209 --> 00:10:45,043 very close near future but sometime in the future. +非常接近的时刻，但是是在未来. 193 00:10:45,045 --> 00:10:48,380 Now, this is so common to do this. Usually we will take out +现在, 这种做法非常普遍。 通常我们会清除掉一些换行， 194 00:10:48,382 --> 00:10:51,349 a little bit of these character-turns here and + 195 00:10:51,351 --> 00:10:55,987 put this all on the same line. Okay, like that. And +Okay, 就像这样。 196 00:10:55,989 --> 00:10:59,524 we're gonna put this after all of our little vars here. +我们要在所有的变量后面增加观察器。 197 00:10:59,526 --> 00:11:02,861 So I'm gonna put it in the place of the comment there. +它要占用注释的位置了。 198 00:11:02,863 --> 00:11:07,565 Put one there. The same thing here just so you can easily +在这里摆放一个。 这里也是相同的操作，你很容易发现 199 00:11:07,567 --> 00:11:11,302 see it cuz they're a little bit screen real estate +它会造成屏幕的空间有些挤。 200 00:11:11,304 --> 00:11:14,205 challenged here. All right, so now all of these vars, +好的, 所有的这些变量, 201 00:11:14,207 --> 00:11:17,475 if someone sets it, it's gonna cause this thing to redraw. +如果有人设置了它们, 就会引起重绘。 202 00:11:17,477 --> 00:11:18,777 What's really cool is if they set three or +如果变量中的三个或四个可以一次性地进行重绘那该多酷 203 00:11:18,779 --> 00:11:21,746 four of them right in a row, it's not gonna redraw three or +而不会引起三四次的重复绘制。 204 00:11:21,748 --> 00:11:23,782 four times. It's gonna keep saying, +它会不断地说, 205 00:11:23,784 --> 00:11:25,750 I need to be displayed, I need to be displayed, +我需要被显示，我需要被显示， 206 00:11:25,752 --> 00:11:25,817 I need to be displayed. +我需要被显示。 207 00:11:25,819 --> 00:11:28,553 But it's not gonna actually display until a little bit +但它不会真正地被显示，直到一段时间后 208 00:11:28,555 --> 00:11:30,822 later, and they'll all get displayed at once. +它们才会被一次性地重绘。 209 00:11:30,824 --> 00:11:33,458 So it's much more better performance to delay, +所以延迟可以提升性能， 210 00:11:33,460 --> 00:11:37,128 slightly, to do these things. That's not even the primary +对这种问题不要太过于重视，这不是主要原因。 211 00:11:37,130 --> 00:11:39,164 reason this is, does, it does it this way, but +实际上 setNeedsDisplay 方法本来就是这样设计的, 不过 212 00:11:39,166 --> 00:11:44,135 it's one of the reasons, okay? Everybody got that? +这只是其中的一个原因, okay? 每个人都理解了吗? 213 00:11:44,137 --> 00:11:46,438 Okay, so we're almost always gonna use this didSet. +Okay, 我们几乎经常会用到 didSet。 214 00:11:46,440 --> 00:11:48,373 Now you're gonna see we're using the didSet in +现在你会看到我们在控制器中 215 00:11:48,375 --> 00:11:50,975 the controller as well for a slightly different reason, +因为一些其他的原因使用 didSet 216 00:11:50,977 --> 00:11:53,111 okay? But the did, didSet is super convenient. +okay? 不过 didSet 真的是超级方便！ 217 00:11:53,113 --> 00:11:57,415 All right, okay so let's talk about our controller here, +好吧, okay 让我们来聊聊控制器， 218 00:11:57,417 --> 00:12:02,020 it needs a model, okay. I have created a little class over +它需要一个模型， okay。 我已经创建好了一个简单的类 219 00:12:02,022 --> 00:12:06,591 here called FacialExpression, which I'm gonna drag in. +叫做 FacialExpression， 现在我把它拖进工程。 220 00:12:06,593 --> 00:12:09,461 I'm gonna copy it in here, okay? When you draw things in, +我把它复制进来, okay? 当你向工程总拖拽东西的时候, 221 00:12:09,463 --> 00:12:10,995 you almost always want this selected. +你几乎总是会把这一项选中。 222 00:12:10,997 --> 00:12:12,997 So pay attention to that, you want it to copy in, you don't +所以注意一下, 你希望它拷贝进来, 223 00:12:12,999 --> 00:12:16,134 really want it having a link to the other thing, +你不希望它链接到别的东西上面 224 00:12:16,136 --> 00:12:16,267 most of the time. +大部分情况下都是这样。 225 00:12:16,269 --> 00:12:19,537 So I'm gonna copy this little FacialExpression in. +所以我要把这个小小的 FacialExpression 拷贝进来. 226 00:12:19,539 --> 00:12:22,474 Let's take a look at FacialExpression. You'll see +让我们来看看 FacialExpression。 227 00:12:22,476 --> 00:12:25,910 we'll see FacialExpression right here, is our model. +你会在这里看到 FacialExpression，它是我们的模型。 228 00:12:25,912 --> 00:12:28,646 See, it's not a UI thing, it imports only foundation. +看到了吗，它不是 UI 方面的东西，它仅仅引入了 foundation。 229 00:12:28,648 --> 00:12:31,549 It's completely UI independent. Its idea of +它完全地与 UI 分离。 它对一张脸的描述 230 00:12:31,551 --> 00:12:34,586 a face is not really the same as a face view. Okay, +和 face view 不同。 Okay, 231 00:12:34,588 --> 00:12:37,388 a face view thinks of mouth curvature and eyebrow tilt and +face view 考虑的是嘴巴的曲率、眼睛的弧度以及 232 00:12:37,390 --> 00:12:40,125 things like that. This doesn't have any of that. It +这方面的东西。完全不包含这个模型里的东西。 233 00:12:40,127 --> 00:12:44,262 does have eyebrows but it just has Relaxed, Normal, Furrowed. +它包含了眉毛的信息，但是只有 Relaxed, Normal, Furrowed这样的描述。 234 00:12:44,264 --> 00:12:46,965 That's the only thing it knows about, those three states. +这三个状态是它唯一知道的。 235 00:12:46,967 --> 00:12:50,001 Same thing with Mouth. It's Frown, Smirk, Neutral, Grin, +嘴巴也是一样。 它的状态是 Frown, Smirk, Neutral, Grin 以及 Smile。 236 00:12:50,003 --> 00:12:52,704 Smile. That's it, it doesn't have mouth curvature. +它就是这样，不包含嘴的曲率。 237 00:12:52,706 --> 00:12:53,872 It doesn't even know what that is, +它甚至不知道曲率什么， 238 00:12:53,874 --> 00:12:57,509 okay? One thing kinda cool here, you see these are enums? +okay? 有一件很有趣的事情，你看到了吗这些都是枚举? 239 00:12:57,511 --> 00:13:00,745 Notice I have functions on my enums here, okay? +请注意我在枚举中定义了方法， okay? 240 00:13:00,747 --> 00:13:03,114 I'm not gonna talk about the implementation of those. +我不打算讨论这些方法的实现. 241 00:13:03,116 --> 00:13:04,249 If you read the reading assignment, +如果你读了作业题目, 242 00:13:04,251 --> 00:13:06,684 you should be able to figure these out. But +你应该可以计算出这些。 243 00:13:06,686 --> 00:13:09,187 I got some functions in here with my enums. But +我在枚举中定义了方法。 但是 244 00:13:09,189 --> 00:13:12,490 really facial expression is just the eyes, eyebrows, and +面部表情依然只有眼睛、眉毛和嘴巴。 245 00:13:12,492 --> 00:13:15,660 mouth, okay, which is specified by these enums. And +okay,使用了这些枚举来表达。 246 00:13:15,662 --> 00:13:18,463 some of the enums like eyes even has a state +枚举中的一部分，比如眼睛，包含了 FaceView 中没有出现的状态。 247 00:13:18,465 --> 00:13:21,900 FaceView can't even represent that face. It doesn't have +FaceView并没有包含一个眯着的眼睛。 248 00:13:21,902 --> 00:13:23,868 a Squinting, it only knows how to have eyes open and +它只知道如何控制眼睛的睁开与闭合。 249 00:13:23,870 --> 00:13:27,705 closed. So the point here is that this model has to be +这里的要点是模型需要被控制器解释给视图 250 00:13:27,707 --> 00:13:31,643 interpreted by the controller for that view, okay? +okay? 251 00:13:31,645 --> 00:13:35,213 The mo, the controller's gonna have to figure out, okay, +此外，控制器必须弄清楚， okay, 252 00:13:35,215 --> 00:13:37,282 what does relaxed eyebrow mean? Well, for +一个 relaxed 的眉毛是什么意思? 好的， 253 00:13:37,284 --> 00:13:39,818 the face view it means some sort of of eyebrow tilt, and +对脸的视图来说，它意味着眉毛的某种倾斜程度, 254 00:13:39,820 --> 00:13:42,253 so the controller has to figure out what that is, and +所以控制器需要把 relaxed 解释给视图， 255 00:13:42,255 --> 00:13:45,824 tell the view, you see? So this shows the primary +看到了吗? 所以这里就解释了控制器在 MVC 中的原始角色 256 00:13:45,826 --> 00:13:50,128 role of a controller in your MVC is to interpret +就是把模型 257 00:13:50,130 --> 00:13:51,563 the model for the view. +解释给视图。 258 00:13:51,565 --> 00:13:54,065 It also interprets input in the view for the model and +它也会把视图中的输入值解释给模型 259 00:13:54,067 --> 00:13:56,401 we'll see that when we talk about gestures, okay. +我们会在讲到手势的时候见到， okay. 260 00:13:56,403 --> 00:13:59,003 That's its kind of primary purpose in the controller. +这就是控制器的原始目的。 261 00:13:59,005 --> 00:14:01,072 So let's make our controller do that, +所以让我们的控制器来做这件事吧。 262 00:14:01,074 --> 00:14:04,943 let's make it turn a facial expression into something in +我们把 facial expression 转换成 263 00:14:04,945 --> 00:14:09,180 the face view, okay. So in our controller, the first thing +视图中的信息， okay。 所以在控制器中，我们要做的第一件事 264 00:14:09,182 --> 00:14:11,749 we're gonna do is we're gonna create a var here, +就是在这里创建一个变量， 265 00:14:11,751 --> 00:14:14,953 which is a pointer to our model, and it's just gonna be +它是一个指向模型的指针, 它是 FacialExpression 类型的 266 00:14:14,955 --> 00:14:17,121 a FacialExpression, okay. And we are even +okay。 我们甚至 267 00:14:17,123 --> 00:14:19,824 gonna set it to some facial expression to start it off +会把它初始化为某种面部表情。 268 00:14:19,826 --> 00:14:22,994 here. Remember we, with the FacialExpression, which is +记住，我们使用的 FacialExpression， 269 00:14:22,996 --> 00:14:28,032 a struct by the way, we get the free constructor. I, +是一个结构体,我们可以使用免费得到的构造器。 我, 270 00:14:28,034 --> 00:14:31,069 by the way, I can infer this. I don't need to have that, +顺便提一句，我可以推断它的类型。 我不需要写出来， 271 00:14:31,071 --> 00:14:34,272 right? So I get the free constructure which is what, +对吗? 我得到的这个免费的构造器中, 272 00:14:34,274 --> 00:14:40,678 eyes are we'll have them be open, and then eyeBrows. +我们让眼睛睁开, 然后是眉毛。 273 00:14:41,114 --> 00:14:44,749 We'll have him be normal. I think is what it is, +我们让眉毛是普通的。我认为它是这样的：普通 274 00:14:44,751 --> 00:14:48,820 normal. And then, we'll have mouth, which will have, +然后我们设置嘴巴， 275 00:14:48,822 --> 00:14:55,293 be a smile I'd say, okay? So this is gonna be our default +像我说过的一个微笑的嘴巴， okay? 这就是 276 00:14:55,395 --> 00:14:58,963 value of our facial expression. +我们的面部描述的默认值。 277 00:14:58,965 --> 00:15:00,732 So this is the model for our MVC. +这就是我们的 MVC 中的模型。 278 00:15:00,734 --> 00:15:05,536 Now what's interesting about this model is what if it +现在这个模型中有趣的部分是 279 00:15:05,538 --> 00:15:09,741 changes? Okay, if it changes, I need to update my view. +如何改变它? Okay, 如果它发生了改变, 我需要更新我的视图。 280 00:15:09,743 --> 00:15:15,046 All right, if, if it changes from smile to a frown +好的, 如果, 如果它从微笑变成了皱眉 281 00:15:15,048 --> 00:15:18,917 I need to change my curvature of my face view. So I'm gonna +我需要改变视图中的曲率。 所以我要 282 00:15:18,919 --> 00:15:23,321 use that same magic the didSet thing that we did before to +使用 didSet 的魔法就像我们之前做的那样 283 00:15:23,323 --> 00:15:27,692 update my UI whenever this facial expression changes. +当模型发生改变的时候更新 UI。 284 00:15:27,694 --> 00:15:31,229 And since this is a value type FacialExpression, +因为这个值的类型是 FacialExpression, 285 00:15:31,231 --> 00:15:34,465 if any of the vars in that value type change, +如果这个变量中的任何属性发生了变化， 286 00:15:34,467 --> 00:15:37,302 this didSet is gonna get called, okay? +didSet 就会被调用, okay? 287 00:15:37,304 --> 00:15:40,104 If this were a class, it wouldn't. So +如果模型是一个类则不会调用 didSet。 288 00:15:40,106 --> 00:15:43,675 luckily it's value type. So this is gonna get called. So +所以庆幸它是个值类型。这部分将会被调用。 289 00:15:43,677 --> 00:15:46,945 we need this update UI. This can be any function we call. +所以我们需要方法更新 UI。 我们可以在这里调用任何方法。 290 00:15:46,947 --> 00:15:48,680 I like calling it function, updateUI, but +我喜欢把这个方法取名为 updateUI。 291 00:15:48,682 --> 00:15:52,417 you can do whatever you want. And it's gonna be private, +你可以取自己喜欢的名字。 这个方法应该是 private 的, 292 00:15:52,419 --> 00:15:53,184 it's a func updateUI. +现在我们有了 updateUI 方法。 293 00:15:53,186 --> 00:15:56,387 And inside here we have to update our faceView. +在它的内部我们需要更新 faceView。 294 00:15:56,389 --> 00:15:59,123 Okay well, if we're gonna update our face view, we need +好的, 如果我们想要更新我们的 faceview，我们需要 295 00:15:59,125 --> 00:16:02,860 a pointer to that as well. Okay, how do we make a pointer +一个指向它的指针。 Okay, 我们该怎样创建一个视图的指针？ 296 00:16:02,862 --> 00:16:06,331 to something in our view? >> Click drag. +>> 单击并且拖动。 297 00:16:06,333 --> 00:16:08,232 Yeah we click, we ctrl drag, right? +我们点击，然后拖动，对吧? 298 00:16:08,234 --> 00:16:09,867 We made an outlet. So let's just do that. +我们创建了一个 outlet。 动起手来吧. 299 00:16:09,869 --> 00:16:13,037 Let's bring our storyboard up here. We've got our face view. +打开 storyboard。我们已经得到了 face view。 300 00:16:13,039 --> 00:16:15,640 Here's our controller right here. I'm just gonna control +控制器在这里。 我将要 301 00:16:15,642 --> 00:16:18,509 drag from the face view into here and I'm gonna create +把 faceView 拖动到这里然后创建一个 302 00:16:18,511 --> 00:16:21,679 an outlet. I'm gonna to call it face view. It's my face +outlet。 取名为face view。它就是我的小人脸 303 00:16:21,681 --> 00:16:24,782 view, okay. We used display in our calculator. This is our +okay。 我们在计算器项目中使用过它进行显示。 这既是我们的小人脸 304 00:16:24,784 --> 00:16:30,588 face view. We click okay here and now we've got this outlet, +我们点击这里的 okay 选项，然后我们得到了一个 outlet， 305 00:16:30,590 --> 00:16:32,156 okay. So now we've got a pointer to this face. +okay. 现在我们得到了一个指向人脸的指针. 306 00:16:32,158 --> 00:16:35,226 So now we can talk to this face set it's curvatures and +接着我们会谈谈如何设置人脸的曲率以及 307 00:16:35,228 --> 00:16:37,628 all that business, right? +所有的这些逻辑，怎么样? 308 00:16:37,630 --> 00:16:42,333 So, now we've got a pointer to this in our update UI. +现在我们得到了这个指针以及 updateUI 方法。 309 00:16:42,335 --> 00:16:44,969 We can just talk to it and set it based on what +我们可以自由讨论视图并且基于面部表情来配置视图。 310 00:16:44,971 --> 00:16:46,838 the expression is. So how are we gonna do that? +所以我们该怎么做呢? 311 00:16:46,840 --> 00:16:50,008 All right, well first of all let's start with the eyes. So +好吧，首先从眼睛开始吧。 312 00:16:50,010 --> 00:16:55,313 if the facial expression's eyes are in the state +如果面部描述中的眼睛是睁开的， 313 00:16:55,315 --> 00:16:59,817 open, then we're gonna send a message to our faceView saying +然后我们就需要向 faceView 发送一条消息告知它 314 00:16:59,819 --> 00:17:03,221 eyes open equals true. So that's an easy one okay our +眼睛睁开的选项是 ture。这很容易办到， 315 00:17:03,223 --> 00:17:06,391 face views very similar to our model in that way, and +在眼睛的配置上模型和视图是相近的， 316 00:17:06,393 --> 00:17:10,461 same thing here closed. We'll do faceview.eyesopen +closed 选项的操作也很相近。 我们会把 faceview.eyesopen 317 00:17:10,463 --> 00:17:15,066 equals false but what about case squinting? +设置为 false 但是 squinting 的情况该怎么办? 318 00:17:15,502 --> 00:17:19,137 Okay, we don't really have faceView.squint, okay we can't +Okay, 实际上我们没有 faceView.squint 这样的属性, 好吧 319 00:17:19,139 --> 00:17:23,307 do that. So I'm just gonna say eyes open equals false. +我们办不到。 所以我只能写 eyes open 为 false. 320 00:17:23,309 --> 00:17:26,878 if you are squinting, eyes are closer to closed than they +如果你是 squinting（斜视）的表情, 眼睛闭上的状态更加贴近一些。 321 00:17:26,880 --> 00:17:28,913 are to open, okay. So it is the best I can do, +okay。 这是我们实现的最好方案， 322 00:17:28,915 --> 00:17:31,482 and this is the way some times a controller is. It's +这就是有时候控制器所发挥的作用。 323 00:17:31,484 --> 00:17:34,886 view might not be perfect at representing the model, it's +这个视图可能并不能很好地展示视图， 324 00:17:34,888 --> 00:17:37,488 doing the best it can. Now it might be, we might be sending +它只能尽力做到最好。现在控制器是这样做的，我们可能会向 face view 中的某一位 325 00:17:37,490 --> 00:17:40,091 in a request to the face view guys on our team saying hey, +发送一个请求，告诉它：嘿，伙计 326 00:17:40,093 --> 00:17:42,460 we wanna feature where our face view will do squinting +我们想让视图能够展示 squinting 327 00:17:42,462 --> 00:17:44,929 because we got squinting in our model. And they might be, +因为我们从模型中得到了一个 squinting 。某些视图可能就会照做， 328 00:17:44,931 --> 00:17:47,465 okay we'll take it under advisement and we'll see. +好吧我们会采纳的，让我们看一下怎么做。 329 00:17:47,467 --> 00:17:48,833 But for now we're kind of stuck. +但是现在我们陷入了困境。 330 00:17:48,835 --> 00:17:53,438 So we're gonna do squinting is the same as eyes closed. +所以我们在处理 squinting 的时候只能让眼睛和 closed 中的情况一样。 331 00:17:53,440 --> 00:17:54,939 How about our other two things? Okay, +那么其他两样东西会怎样呢? Okay， 332 00:17:54,941 --> 00:17:56,374 we've got these curvatures to deal with, right? +我们有这些曲率需要处理，对吧? 333 00:17:56,376 --> 00:18:01,512 So, we want to say something like faceView.mouthCurvature = +我们想要写 faceView.mouthCurvature = 334 00:18:01,514 --> 00:18:05,650 something based on the expression's mouth. But +模型中关于嘴部曲率描述的值。 335 00:18:05,652 --> 00:18:08,553 the expression's mouth is like grin and frown. +嘴巴的描述就像 grin 和 frown。 336 00:18:08,555 --> 00:18:09,187 What the heck are we gonna do? +我们要做些什么? 337 00:18:09,189 --> 00:18:11,289 How are we gonna convert that to a curvature? +我们该如何把它们转化成曲率? 338 00:18:11,291 --> 00:18:11,856 And what I'm gonna do is, +现在我就来解决这个问题， 339 00:18:11,858 --> 00:18:16,360 I'm actually going to create a little private dictionary, +我想要创建一个轻量的私有的字典， 340 00:18:16,362 --> 00:18:21,199 I'm gonna call it mouthCurvatures. Okay, plural +我会给它取名为 mouthCurvatures. Okay, 一对括号 341 00:18:21,201 --> 00:18:25,002 and I'm gonna make it equal to a dictionary. Remember, +并且我要让它等于一个字典。 记住， 342 00:18:25,004 --> 00:18:27,338 we can make a dictionary on the fly with square brackets. +我们可以使用一对方括号创建一个字典。 343 00:18:27,340 --> 00:18:30,541 And then I'm gonna have the keys of this dictionary be +接下来我准备给这个字典设置一些键值来匹配 344 00:18:30,543 --> 00:18:31,909 mouthCurvatures for my model and +模型中的嘴巴曲率。 345 00:18:31,911 --> 00:18:35,146 I'm gonna have the values be mouthCurvatures for my view. +字典的值对应了视图中的嘴巴曲率。 346 00:18:35,148 --> 00:18:40,118 Okay, doubles. All right, so for example let's do +好的， double 类型。举个例子，让我们增加一个新的成员 347 00:18:40,120 --> 00:18:44,722 FacialExpression.Mouth.Frown. Okay, that's +FacialExpression.Mouth.Frown。 Okay, 这是键值。 348 00:18:44,724 --> 00:18:47,892 the key. And the values gonna be -1.0 that's the curvature +对应的值为 -1.0，这是该种状态的嘴巴的曲率。 349 00:18:47,894 --> 00:18:50,194 that goes along with that. See what I'm saying? So +看到了我所说的了吗? 350 00:18:50,196 --> 00:18:52,497 I'm just creating this dictionary that's mapping +我创建这个字典的目的是 351 00:18:52,499 --> 00:18:59,103 between my model and my view. So how about Grin? Notice but +映射模型与视图中的值。 那么 Grin（咧嘴）该是什么样? 352 00:18:59,105 --> 00:19:02,473 by the way, when I do Grin, okay, it's already inferred to +顺便说一句， 当我咧嘴的时候, okay, 系统的类型推断已经推测出了字典的键是 353 00:19:02,475 --> 00:19:04,342 the fact that we're doing a FacialExpression.Mouth. +一个 FacialExpression.Mouth 类型的。 354 00:19:04,344 --> 00:19:07,578 So and I do, don't need to repeat this every single time. +因此我会这样做, 不需要每次都重复写前缀。 355 00:19:07,580 --> 00:19:10,448 I can just say the Grin. and the Grin, we'll say, is 0.5. +我可以只写 Grin。我们把 Grin 设定为 0.5。 356 00:19:10,450 --> 00:19:12,617 So it's not a full smile, just kind of a little bit +所以它不是开怀大笑，只是微微一笑的程度。 357 00:19:12,619 --> 00:19:16,854 of a smile. But a full smile would be 1.0 and +开怀大笑的曲率是 1.0 358 00:19:16,856 --> 00:19:22,660 a Smirk, now that sounds kinda like a little bit of a frown, +一个 Smirk（傻笑）, 听起来有点像皱眉， 359 00:19:22,662 --> 00:19:23,227 but not too much of one. +但是不是同一个表情。 360 00:19:23,229 --> 00:19:27,165 So, we'll -0.5 right there and then there's this neutral +我们把这种表情的值设为 -0.5 361 00:19:27,167 --> 00:19:31,736 mouth position which we'll have be zero point zero. Okay, +最后还有一个 Neutral（中立）的表情，把它的值 设为 0.0。Okay， 362 00:19:31,738 --> 00:19:34,172 so, I created these mouth curvatures in a table. So now, +我把嘴巴的曲率装进了一个列表中。 现在， 363 00:19:34,174 --> 00:19:38,242 down here, I can just let my mouth curvature equal mouth +完成了, 我可以把模型的 mouth 属性所提供的信息转换成 364 00:19:38,244 --> 00:19:42,780 curvatures sub expression.mouth. +嘴巴视图的曲率。 365 00:19:42,782 --> 00:19:45,683 Okay, now the problem with this, and you can see there's +Okay, 现在遇到了问题，你可以看到这里有一个报错。 366 00:19:45,685 --> 00:19:49,420 an error here. And can anyone see what the problem here is? +所有人都能看到这里出问题了吧? 367 00:19:49,822 --> 00:19:53,824 This is a dictionary lookup. What is a dictionary lookup? +这是一个字典的查找。 字典的查找是什么? 368 00:19:53,826 --> 00:19:56,861 What type does it return? Optional, +它返回什么类型? 可选型。 369 00:19:56,863 --> 00:20:00,965 yeah, so this is a double. It's not an optional, okay? +耶， 这是个小麻烦。 它不是个可选型， okay? 370 00:20:00,967 --> 00:20:02,200 So how are we gonna deal with this? +所以我们该如何处理? 371 00:20:02,202 --> 00:20:07,972 What if facial expression gets enhanced some future date and +如果 Facial Expression 未来增加一些特性并且 372 00:20:07,974 --> 00:20:10,107 the expression's not in here? +这些新的表情不在这个字典里该怎么办? 373 00:20:10,109 --> 00:20:14,345 I'm going to have it default to zero. Okay? +我把它的默认值设为 0.0。 Okay? 374 00:20:14,347 --> 00:20:18,749 Remember this defaulting thing right here where you can take +记得在这里设置一个默认值 375 00:20:18,751 --> 00:20:23,020 something that's a double and if it turns into to nil if it +当你想要获取某个 double 类型的值，当它遇到nil时 376 00:20:23,022 --> 00:20:27,024 returns nil then you can have a default value there, +你会得到一个默认的 double 值, 377 00:20:27,026 --> 00:20:30,361 make sense? Var there. Okay, everyone's +明白了吗? 这里加上 var。 Okay 378 00:20:30,363 --> 00:20:34,131 cool with what I did there? All right, hopefully if you +我这里的处理很酷吧? 好的， 希望你在计算器项目中用到过它 379 00:20:34,133 --> 00:20:36,300 solve it from calculator it's very similar to that, +这里和那个项目中的情况很像。 380 00:20:36,302 --> 00:20:38,636 looking things up in the dictionary. So I'm gonna +在字典中查找东西。 接下来 381 00:20:38,638 --> 00:20:41,038 do with the same thing with the eyebrow tilt okay +我要给眉毛的曲率做相同处理。 okay 382 00:20:41,040 --> 00:20:44,208 the eyeBrowTilt equals eyeBrowTilts +eyeBrowTilt 等于 eyeBrowTilts（一个待生成的字典） 383 00:20:44,210 --> 00:20:48,446 which is gonna be a dictionary and I'm gonna put the, +并且我要用一个 expression.eyebrows 作为索引。 384 00:20:48,448 --> 00:20:53,651 a facial expression.eyebrows in there and +然后当我们查找不到的时候 385 00:20:53,653 --> 00:20:57,822 also default that one to zero if we can't find it. And +依旧设置为 0.0。 386 00:20:57,824 --> 00:20:59,991 then I'll just make a private var here, +接下来我在这里定义一个私有变量， 387 00:20:59,993 --> 00:21:02,393 we'll call it eyeBrowTilts And +取名为 eyeBrowTilts 388 00:21:02,395 --> 00:21:09,000 this one we'll do FacialExpression.Eyebrows. +用来处理 FacialExpression.Eyebrows。 389 00:21:09,002 --> 00:21:11,669 What do we got here, relaxed: so +这里需要填写的东西有 relaxed 390 00:21:11,671 --> 00:21:16,707 we'll have relaxed be a CGFloat, which is 0.5, so +我们要把 relaxed 解释成一个 CGFloat，值为 0.5， 391 00:21:16,709 --> 00:21:20,211 it's kind of relaxed eyebrows notice I. +这是一种放松的眉毛。注意 392 00:21:20,213 --> 00:21:23,681 Oops not CGFloat, that's 0.5 okay that's a double, +它不是 CGFloat，字面量是 0.5 okay 所以它是一个 double， 393 00:21:23,683 --> 00:21:25,583 okay the eyebrow tilts are doubles. +okay 现在眉毛的倾斜度是 double 类型了。 394 00:21:25,585 --> 00:21:29,220 So we don't I did not want CG float there. +这里我们不想要一个 CGFloat 类型。 395 00:21:29,222 --> 00:21:35,092 Okay how about .furrowed is -0.5 tilt and +Okay .furrowed 是 -0.5 的倾斜度 396 00:21:35,094 --> 00:21:41,132 .normal we'll make be 0. Okay? +.normal 我们设为 0。 Okay? 397 00:21:41,968 --> 00:21:46,337 Got that? All make sense? So we are doing the same look up +明白了吗? 所有人都明白了吗? 我们这里做了相同的查找。 398 00:21:46,339 --> 00:21:51,309 there. Okay so we've matched up our model with our view. +我们把模型与视图进行了配对。 399 00:21:51,311 --> 00:21:54,945 We've kind of interpreted our model for view. Now, +我们创建了一个为视图解释模型的控制器。 现在， 400 00:21:54,947 --> 00:21:59,150 lets go ahead and run this and see what this looks like. +让我们继续并且运行程序，看看是什么样子。 401 00:22:04,223 --> 00:22:08,025 Okay, now, hmm this doesn't quite look right. Because, +Okay, 现在，这个表情看起来不太对。 因为， 402 00:22:08,027 --> 00:22:11,095 if we look at our model it's supposed to be eyes open. +如果你查看我们的模型就会发现，从模型中看眼睛应该睁开。 403 00:22:11,097 --> 00:22:13,931 Okay, that's good. Eyebrows normal. No. +Okay, 这很棒。 眉毛是 normal。不。 404 00:22:13,933 --> 00:22:16,200 Those are not normal eyebrows, those are kinda furrowed. +屏幕上的眉毛不是 normal 的。没有有点皱。 405 00:22:16,202 --> 00:22:20,071 And mouth is supposed to be smile. Hmm, no, it's a frown. +并且嘴巴应该是 smile。 恩...， 不，这是一个 frown（愁眉苦脸） 的嘴型。 406 00:22:20,073 --> 00:22:24,175 In fact, all of this here instead of the UI looking like +实际上，所有的这些面部表情不像是模型所表达的， 407 00:22:24,177 --> 00:22:28,212 the model it still looks like we set it in the storyboard. +而是 storyboard 上的。 408 00:22:28,214 --> 00:22:32,717 Okay, so, why is it that our update UI is not getting +Okay，那么，为什么当我们初始化一个表情的时候 409 00:22:32,719 --> 00:22:37,188 called here when we initialize our facial expression? +我们更新 UI 的逻辑没有实现呢？ 410 00:22:37,190 --> 00:22:39,957 That's because if you're setting a value during +这是因为当你通过构造器初始化一个值的时候 411 00:22:39,959 --> 00:22:44,929 initialization, didSet is not called. Okay? +didSet 不会执行。 Okay? 412 00:22:44,931 --> 00:22:48,966 It's only called if you set it later. Now why is that? +当你稍后对它赋值的时候 didSet 才会执行。这是为什么 ？ 413 00:22:48,968 --> 00:22:52,169 Because you know that when things are being initialized +因为你知道的在 Swift 中，当对象被初始化的时候， 414 00:22:52,171 --> 00:22:54,305 in Swift, they have to be fully initialized before +在你对它做任何操作之前， 415 00:22:54,307 --> 00:22:57,241 you can do anything with them. So of course, they have to be +它必须被完全初始化。 所以理所当然的，当你想对 expression 416 00:22:57,243 --> 00:22:59,009 fully initialized before you can do any of this +做任何修改时，它必须被完全初始化。 417 00:22:59,011 --> 00:23:03,581 stuff either. Okay? So, this initialization did happen, but +Okay? 因此,这个对象已经初始化了, 但是 418 00:23:03,583 --> 00:23:05,983 this, you updateUI didn't get called because this was +你的 updateUI 没有被调用，因为 419 00:23:05,985 --> 00:23:07,918 happening during the initialization phase of our +expression 的初始化过程发生在 420 00:23:07,920 --> 00:23:10,821 faceView controller. Now, if we were to set the expression +faceView controller 的初始化过程中。 现在， 如果我们稍后去设置 expression 421 00:23:10,823 --> 00:23:14,325 later, this would get called, our UI would change. So, +updateUI 方法会被调用。 我们的 UI 会发生改变。所以， 422 00:23:14,327 --> 00:23:16,927 how do we deal with that? Okay, what we are gonna do +我们该如何处理？ Okay。 有些事情无论如何我们都需要做 423 00:23:16,929 --> 00:23:20,131 there is something we should of done anyway. Which is, +那就是 424 00:23:20,133 --> 00:23:25,669 when our face view outlet is set by the system. +当我们的 faceView 的 outlet 被系统设置好的时候。 425 00:23:25,671 --> 00:23:30,040 We are gonna do didSet here and Update our UI. Okay? +我们在它的 didSet 中更新我们的 UI。 Okay? 426 00:23:30,042 --> 00:23:35,279 So, this didSet is called when iOS comes along shortly after +所以, 这里的 didSet 会在你的 MVC 创建不久之后 427 00:23:35,281 --> 00:23:39,250 your MVC is created, and it wires up this outlet. Okay? +被 iOS 系统所调用, 它会关联这个 outlet。 Okay? 428 00:23:39,252 --> 00:23:42,019 It hooks up the outlet so it's actually pointing to that face +系统会钩住（hook up）这个 outlet，让它指向内存中的 faceView。 429 00:23:42,021 --> 00:23:45,089 view. So, as soon as that happens, now we have +这样的话，只要这个过程发生，我们 430 00:23:45,091 --> 00:23:49,393 a hold of our face view. Now we can update it. Okay, so +就会持有我们的 faceView 了。现在我们可以更新 UI 了。 Okay，所以 431 00:23:49,395 --> 00:23:51,929 we are updating it both when our model changes and +当我们的模型发生变化以及我们的 faceView 第一次被系统钩住的时候， 432 00:23:51,931 --> 00:23:56,767 the first time our view is hooked up. Okay. +我们都会更新 UI。 Okay。 433 00:23:56,769 --> 00:24:00,171 And this is something also that we would usually +我们经常把 didSet 与对象 434 00:24:00,173 --> 00:24:02,339 put on the end like this. +写在同一行。 435 00:24:07,747 --> 00:24:10,347 Okay we might even do it here I might even leave this here +我们可以像上面这样写，这里我的代码保持这个写法 436 00:24:10,349 --> 00:24:13,083 just to emphasize that we're doing this but again this +只是为了强调我们可以这么写 437 00:24:13,085 --> 00:24:16,587 would be a common thing to throw on the end there okay. +不过写在末尾是更常见的写法。 438 00:24:16,589 --> 00:24:21,091 All right, so now let's run, now when Swift +好的，现在运行一下，当 Swift（错说了） 439 00:24:21,093 --> 00:24:24,161 iOS basically comes along and hooks up that face view. +iOS 系统基本启动并且钩住了 faceView 之后， 440 00:24:24,163 --> 00:24:28,165 Boom. It's going to be updated with our model, okay? +Boom~。 faceView 就更新到模型中描述的样子了， okay? 441 00:24:28,167 --> 00:24:30,634 And so now if we change our model here, let's make +并且现在如果我们修改模型，让我们把 442 00:24:30,636 --> 00:24:35,773 the eyebrows be relaxed. We'll make the mouth be a smirk. +眉毛设置为 relaxed（放松），把嘴巴设置为 smirk（傻笑）。 443 00:24:35,775 --> 00:24:39,610 Let's get those eyes closed. Okay. And we change all of +让眼睛闭上。 Okay。 我们改变了模型中的 444 00:24:39,612 --> 00:24:42,613 this in the model, then our view should be reflecting our +所有属性， 我们的视图会按照模型进行更新。 445 00:24:42,615 --> 00:24:49,553 model. Okay, and there it is. Kay? All good? +Okay, 就是这样 Okay? 都很棒吧? 446 00:24:49,555 --> 00:24:53,057 Everyone understand what we're doing there with our model? +所有人都理解我们对模型做了什么事情吧? 447 00:24:53,793 --> 00:24:57,061 Okay. So let's go back to the slides and +Okay。 让我们回到幻灯片。 448 00:24:57,063 --> 00:25:00,030 talk a little bit about gestures and then we'll come +让我们来讨论一下手势，并且我们将会回到项目中 449 00:25:00,032 --> 00:25:04,301 back and add some gestures to our FACEIT right here. +并且向其中增加一些手势。 450 00:25:11,711 --> 00:25:15,513 Okay. So, we saw last time how to draw in a view. +Okay。 所以，刚才我们看到了如何在视图中绘制。 451 00:25:15,515 --> 00:25:19,116 We drew the mouth, we drew the eyes, we did the eyebrows, but +我们画了嘴、眼睛和眉毛，所有的这一切。 452 00:25:19,118 --> 00:25:22,086 all of these things. We know how to do that pretty much, +我们知道如何做到这一点， 453 00:25:22,088 --> 00:25:22,653 right? We're using the use, +对吧? 我们在绘制的区域使用了 454 00:25:22,655 --> 00:25:25,689 UI bezier path in our draw rect, not so hard. +UIBezierpath，并不复杂。 455 00:25:25,691 --> 00:25:29,727 What about gestures? Okay? So this is input from the user on +那么手势呢? Okay? 这是用户在屏幕上的输入方式之一。 456 00:25:29,729 --> 00:25:35,733 the screen. Now, we can get the location and movement +现在， 我们可以得到每一次单个手指触碰到屏幕时的 457 00:25:35,735 --> 00:25:38,235 of every single finger that touches down on the screen, +位置和运动轨迹， 458 00:25:38,237 --> 00:25:42,573 that's possible. Okay? There's API for doing that, but we +这是可以实现。 Okay? 捕获手势有专门的 API，不过我们 459 00:25:42,575 --> 00:25:46,010 virtually never do that ever. Okay? Why don't we do that? +几乎从来没有用过这些 API。 Okay? 我们为什么不用? 460 00:25:46,012 --> 00:25:49,547 The reason for that is that the user thinks of interacting +原因是用户认为当他们在屏幕上使用手势进行交互时 461 00:25:49,549 --> 00:25:53,417 with your UI as a gesture, like, they're swiping, or +他们使用的手势是具体的， 462 00:25:53,419 --> 00:25:56,787 they're pinching. Okay, where they're panning around. +比如滑动或者捏合。 463 00:25:56,789 --> 00:25:59,023 Those are gestures that they're making. +这些是他们正在做的手势。 464 00:25:59,025 --> 00:26:02,259 So iOS has an abstraction layer that lets your +所以 iOS 系统中有一个抽象层 465 00:26:02,261 --> 00:26:06,630 app think of the input as gestures as well, okay? So +让你的应用可以把屏幕上的交互识别为对应的手势， okay? 466 00:26:06,632 --> 00:26:07,398 you're gonna get those gestures and +所以你就可以得到这些手势并且 467 00:26:07,400 --> 00:26:10,067 do something when they happen. There's predefined gestures. +当它们产生的时候做相应的处理。 这些都是预定义的手势。 468 00:26:10,069 --> 00:26:13,304 The great thing about that is, a swipe is exactly the same +很棒的一点是，在每一个单独的应用中 469 00:26:13,306 --> 00:26:16,273 thing in every single app. Okay? It's like, you know, +滑动手势都是类似的。 Okay? 你知道的，就好比， 470 00:26:16,275 --> 00:26:19,209 know, the speed of swiping and how far you have to swipe, +滑动的速度以及你需要滑动的距离， 471 00:26:19,211 --> 00:26:20,778 all that's exactly the same in every single app, +在每一个应用中这些都是相同的， 472 00:26:20,780 --> 00:26:23,247 cuz every single app is using these gestures. Okay, +这是因为每一个应用都用了相同的手势。 Okay, 473 00:26:23,249 --> 00:26:25,716 if you had to do your own swipe, well, you know, +如果你想要做自己的滑动手势，好吧，如你所知 474 00:26:25,718 --> 00:26:27,017 did, did the person swipe fast enough? +多快速的动作算是滑动? 475 00:26:27,019 --> 00:26:29,853 Or was that a pan? You'd have to do all that logic yourself. +或者那是一个点击手势吗? 你必须去独自处理这些逻辑。 476 00:26:29,855 --> 00:26:30,487 It would be a pain in the neck, and +这将是一个痛苦的过程，并且 477 00:26:30,489 --> 00:26:34,525 it would be inconsistent between applications. Okay. So +不同的程序间将会不一致。 Okay。所以 478 00:26:34,527 --> 00:26:38,696 gestures are recognized by instances of a class called +手势会被一个叫做 UIGestureRecognizer 的实例识别。 479 00:26:38,698 --> 00:26:42,066 UIGestureRecognizer. Okay, good name. But +Okay，好名字。不过 480 00:26:42,068 --> 00:26:44,468 UIGestureRecognizer itself is abstract. +UIGestureRecognizer 这个类本身是个抽象类。 481 00:26:44,470 --> 00:26:47,771 You never actually instatiate one. Instead there's a bunch +你永远都不会实例化它。 取而代之的是一组 482 00:26:47,773 --> 00:26:50,140 of sub-classes of UIGestureRecognizer. And +UIGestureRecognizer 的子类。 483 00:26:50,142 --> 00:26:53,777 those are what you instantiate to get the kind of gesture you +这些子类才是你需要根据具体的手势进行实例化的对象。 484 00:26:53,779 --> 00:26:55,746 want. So there's pan gesture recognizer and +所以会有 pan gesture recognizer、 485 00:26:55,748 --> 00:26:58,916 pinch gesture resto recognizer and tap and swipe gesture +pinch gesture recognizer 以及 tap 和 swipe gesture 486 00:26:58,918 --> 00:27:03,554 recognizer etc. Okay. Now when you wanna use a recognizer, +recognizer 等等。 Okay。现在当你想要使用一个识别器的时候， 487 00:27:03,556 --> 00:27:06,256 there's really two parts to it, okay. +它需要包含两部分, okay。 488 00:27:06,258 --> 00:27:11,028 One is you have to get some UIView to. +一个是在其上识别手势的 UIView。 489 00:27:11,030 --> 00:27:14,465 Take on this gesture recognizer and recognize that +把这个手势识别器加到视图上然后识别对应的手势。 490 00:27:14,467 --> 00:27:17,034 gesture. So there's the gesture recognition part +所以这一步需要你 491 00:27:17,036 --> 00:27:19,203 which is done by creating a gesture recognizer and +创建一个手势识别器然后 492 00:27:19,205 --> 00:27:23,107 then a view to use it. Only views can recognize gesdri, +指定一个视图去使用它。 只有视图才能识别手势， 493 00:27:23,109 --> 00:27:27,077 gestures not controllers. They can't recognize it only views. +控制器不能识别手势。 494 00:27:27,079 --> 00:27:29,947 Okay? So part one is to create the gesture recognizer you +Okay? 所以第一步就是创建你想要的手势识别器 495 00:27:29,949 --> 00:27:31,682 want, configure it how you want, and +按照你的想法配置它，并且 496 00:27:31,684 --> 00:27:35,619 then ask some view please start recognizing this. Okay? +指派一些视图开始识别。 Okay? 497 00:27:35,621 --> 00:27:39,957 Then part two is, what if the recognizer does recognize it? +然后第二步， 手势识别器识别了手势之后该做什么？ 498 00:27:39,959 --> 00:27:43,193 Then it needs to have that handled some how. And +它需要一些处理。 499 00:27:43,195 --> 00:27:44,995 that's done with a gesture handler. +这一步通过一个手势处理器（gesture handler）来完成。 500 00:27:44,997 --> 00:27:46,664 @@ -6133,3 +6632,4 @@ if you have any questions. >> For 01:16:23,746 --> 01:16:23,777 more, please visit us at stanford.edu. + From 353f1e9a995d3a72243d58c4e36a08e0a925d403 Mon Sep 17 00:00:00 2001 From: Xinyu Zhao Date: Tue, 6 Dec 2016 10:24:13 +0800 Subject: [PATCH 18/23] Delete .DS_Store --- .DS_Store | Bin 6148 -> 0 bytes 1 file changed, 0 insertions(+), 0 deletions(-) delete mode 100644 .DS_Store diff --git a/.DS_Store b/.DS_Store deleted file mode 100644 index 5b41c0c4316bdea87bf038b1c5a667af5d039779..0000000000000000000000000000000000000000 GIT binary patch literal 0 HcmV?d00001 literal 6148 zcmeHKPjAyO6o2kINY_gcAWh=pBS;l0?O@lebVwW~RSVjL7%B;gsHG5BO}YqGm2&3J z7vTT*Kycy<@KHFG_iT4s$habe{G#XI^NW9W^K%;80Kf+G=njAj01i4~qlLuDVj$;fl%4pxzhe>Qld*e!G>cD>IttSGNMs@uiO63$ExN|;_F~cR z^*g+`(_41F-=9(RA!DCOw%#XO*_wEsZrB`nZpM&BQtYCVQO^j zpR4A;JdL)r3RnfI3T)`AOY8sspU?kQlC4<W@v7~9fPyp665^PB=i&tRz$GiY`rpk%OxRp75G@C&(Lin#y) From 0877ef63c040cfce5259745a3f3322c99bd6a915 Mon Sep 17 00:00:00 2001 From: Xinyu Zhao Date: Tue, 6 Dec 2016 10:24:25 +0800 Subject: [PATCH 19/23] Delete .DS_Store --- subtitles/.DS_Store | Bin 8196 -> 0 bytes 1 file changed, 0 insertions(+), 0 deletions(-) delete mode 100644 subtitles/.DS_Store diff --git a/subtitles/.DS_Store b/subtitles/.DS_Store deleted file mode 100644 index 1159ffb997b1ef207e44679b10e63153eabf5a30..0000000000000000000000000000000000000000 GIT binary patch literal 0 HcmV?d00001 literal 8196 zcmeHM&2AGh5FSGhmEb^&gnB_Thyx&0DF58jG%YGLv?5i-k^ZD5B2A)ALfcy&gNNb) zcm&=8zHjW!dehyA140$pl6Smo&&=m<#@=`%BBnY#SQ1$fky%vAYgce7DC}oFS1$P{ z^NWvnuaSYsz?9i(Tn(2kjP-Y-QC}7clUsW z%Xba+?oTafiOd1tqcOrnzb@2(W`J63;Ttx9*}%dLSjgs>w_v3Pi^srOXv@5xur&`$ zj}^@_X3rUK0LK|5?}}}FpRjQgHlC=BcVKE8Y#aka0>)B~mcb{Va+Z$WLd)dJoCY(! z1Lg*rgH120YV6s;3RCT}IpOBa_jSm^-2 zmAdSJ?@}wd)pp-!CNsn3NVZjzfzKWM4C((oQ*FOX_$9s2t|7T||{FcnU^Wytof3j(c{*&+jUwz{-&j0`b From 8e6749cfed8f6ffe4270745154fc420709c83482 Mon Sep 17 00:00:00 2001 From: Donie Leigh Date: Mon, 26 Dec 2016 22:37:25 +0800 Subject: [PATCH 20/23] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E7=BF=BB=E8=AF=91?= =?UTF-8?q?=E9=94=99=E8=AF=AF=20(#54)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- ...rse Overview and Introduction to iOS, Xcode, and Swift.srt | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt b/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt index 35a6c8b..aef3a9f 100755 --- a/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt +++ b/subtitles/1. Course Overview and Introduction to iOS, Xcode, and Swift.srt @@ -5676,7 +5676,7 @@ doing empty string to mean a button without a title? 1139 00:57:05,122 --> 00:57:10,492 Or maybe for an int minus 1. I don't know. Or for a point or -或者是一个最小为 1 的 int +或者是一个 -1 的 int 1140 00:57:10,494 --> 00:57:14,463 @@ -5706,7 +5706,7 @@ For an int, if you wanted an optional int, is it minus 1 or 1145 00:57:28,078 --> 00:57:31,280 0, max int? What is it, it don't know what it is. -它到底是 1？是 0？还是别的什么？他不知道应该是多少。 +它到底是 -1？是 0？还是别的什么？他不知道应该是多少。 1146 00:57:31,282 --> 00:57:34,817 From 13af068cba4353a4c6bce9c4b071ac9ac65f99bc Mon Sep 17 00:00:00 2001 From: Donie Leigh Date: Wed, 28 Dec 2016 18:37:25 +0800 Subject: [PATCH 21/23] =?UTF-8?q?=E4=BF=AE=E6=94=B9=E7=BF=BB=E8=AF=91?= =?UTF-8?q?=E9=94=99=E8=AF=AF=20(#55)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * 修改翻译错误 * 修改翻译错误 --- subtitles/2. Applying MVC.srt | 2 +- ...3. More Swift and Foundation Framework.srt | 60 +++++++++---------- 2 files changed, 31 insertions(+), 31 deletions(-) diff --git a/subtitles/2. Applying MVC.srt b/subtitles/2. Applying MVC.srt index 4d56d28..59240d8 100755 --- a/subtitles/2. Applying MVC.srt +++ b/subtitles/2. Applying MVC.srt @@ -609,7 +609,7 @@ I was touched or something like that. Okay. For example, 123 00:05:59,920 --> 00:06:03,554 -it might be a school view, that's a generic view minion. +it might be a scroll view, that's a generic view minion. 例如一个通用的滚动视图, 124 diff --git a/subtitles/3. More Swift and Foundation Framework.srt b/subtitles/3. More Swift and Foundation Framework.srt index 79becc2..13ef40e 100755 --- a/subtitles/3. More Swift and Foundation Framework.srt +++ b/subtitles/3. More Swift and Foundation Framework.srt @@ -241,7 +241,7 @@ unwrapping an Optional that's not said is supposed to do, 49 00:02:35,550 --> 00:02:40,450 it's supposed to crash, okay? And of course, in the case -它应该让程序奔溃。 +它应该让程序崩溃。 50 00:02:40,450 --> 00:02:44,420 @@ -440,8 +440,8 @@ x is right there? >> [INAUDIBLE]. 88 00:04:46,980 --> 00:04:48,780 ->> Int, almost. -[大概是 Int] +>> Int? almost. +Int? 差不多。 89 00:04:48,780 --> 00:04:51,780 @@ -901,7 +901,7 @@ height, obviously straight forward how we do that. 180 00:09:47,210 --> 00:09:50,010 So tuples are perfectly valid return values, okay? So -所以tuople 用来返回值是非常有效的，好的。 +所以tuple 用来返回值是非常有效的，好的。 181 00:09:50,010 --> 00:09:52,910 @@ -936,7 +936,7 @@ so you can have a range of ints. You can have 187 00:10:13,240 --> 00:10:16,900 a range of indexes into something or whatever it -你可以有一个莫些东西内部的索引范围 +你可以有一个某些东西内部的索引范围 188 00:10:16,910 --> 00:10:20,240 @@ -1170,8 +1170,8 @@ properties. Only structs and classes can have stored 234 00:12:46,160 --> 00:12:50,160 -properties but enums can have computer properties. Okay? -但是枚举可以计算属性 +properties but enums can have computed properties. Okay? +但是枚举可以包含计算属性 235 00:12:50,160 --> 00:12:52,830 @@ -1261,11 +1261,11 @@ as argument to a function, that's kind of obvious. But 252 00:13:45,980 --> 00:13:50,480 it also copies when you assign it to another variable. -当你把他分配个另一个变量时它也会拷贝 +当你把它分配个另一个变量时它也会拷贝 253 00:13:50,490 --> 00:13:54,250 -If I say varx=y if y is a value type, +If I say var x = y if y is a value type, 如果我说var x = y 如果y 是一个值类型 254 @@ -1316,7 +1316,7 @@ Okay? So if you have an array okay, 263 00:14:24,490 --> 00:14:26,990 since that value symmentic cuz an array is a struct. -因为array 是一个 strut +因为array 是一个 struct 264 00:14:26,990 --> 00:14:30,220 @@ -1331,7 +1331,7 @@ append things on to that array cuz it is immutable. Okay, 266 00:14:33,930 --> 00:14:38,170 same thing with the dictionary or whatever. Okay. Remember -dictrionary 或者其它东西在这一点上也是相同的 +dictionary 或者其它东西在这一点上也是相同的 267 00:14:38,170 --> 00:14:40,300 @@ -1386,7 +1386,7 @@ It gets another pointer to it but as soon as you try to 277 00:15:11,430 --> 00:15:15,370 mutate it then it's gonna have to copy it. You see? So -会用一个指正指向它并拷贝这个指针 +会用一个指针指向它并拷贝这个指针 278 00:15:15,370 --> 00:15:17,640 @@ -1411,7 +1411,7 @@ you have to put mutating in front so Swift knows 282 00:15:25,580 --> 00:15:30,220 that you're doing that. Okay, reference types, okay. -好的，参考类型 +好的，引用类型 283 00:15:30,220 --> 00:15:30,850 @@ -1456,7 +1456,7 @@ it keeps incrementing a count. And when that count goes down 291 00:15:49,970 --> 00:15:53,070 to zero because maybe the last pointer that's pointing to it -可能是最后一个指针不在指向它了 +可能是最后一个指针不再指向它了 292 00:15:53,080 --> 00:15:56,140 @@ -1466,7 +1466,7 @@ goes out of scope or maybe you assign that last pointer to 293 00:15:56,150 --> 00:15:58,910 point to something else. Nothing points to it. -这块内存不在被指向的时候 +这块内存不再被指向的时候 294 00:15:58,910 --> 00:16:00,510 @@ -1666,7 +1666,7 @@ certainly gonna use the class, all right? Okay. 333 00:17:50,660 --> 00:17:53,730 On the methods. So now we are gonna talk about the syntax -好的。这这些方法里，我们要来说说这些方法的语法 +好的。在这些方法里，我们要来说说这些方法的语法 334 00:17:53,730 --> 00:17:57,360 @@ -1760,7 +1760,7 @@ Don't appear anywhere here. Notice first and 352 00:18:53,090 --> 00:18:56,660 second do not appear in the funk bar call. Okay, -注意第一个和第二够不在方法块后面出现 +注意第一个和第二个不在方法块后面出现 353 00:18:56,660 --> 00:19:00,190 @@ -1770,7 +1770,7 @@ cuz those are the internal names. The external name 354 00:19:00,200 --> 00:19:04,760 is what the caller uses when they call this method. Okay, -当这个方法被调用的时候这个方法会被使用 +外部名字是这个方法的调用者使用的。 355 00:19:04,770 --> 00:19:09,200 @@ -1784,13 +1784,13 @@ externalSecond: 5.5, right? Okay, it's using the external 357 00:19:14,180 --> 00:19:16,110 -names first and second never appear but -第一个和第二个名字并没有出现 +names. first and second never appear but +first和second并没有出现 358 00:19:16,110 --> 00:19:19,480 first and second are still used in the implementation, -但它们仍然能够被实现别使用 +但first和second在代码实现中仍然被使用了， 359 00:19:19,480 --> 00:19:22,850 @@ -1890,7 +1890,7 @@ that the second one has no name, okay? 378 00:20:32,320 --> 00:20:35,690 But don't do this, okay? It's very anti Swift -当时不要这样做，好吗？ +但是不要这样做，好吗？ 379 00:20:35,690 --> 00:20:39,890 @@ -1968,7 +1968,7 @@ a subclass can't say override that thing. The compiler won't 394 00:21:24,740 --> 00:21:29,110 let them. Okay, you can also mark an entire class final, -你也可以在类的最后标记一个入口 +你也可以标记整个类为final 395 00:21:29,110 --> 00:21:33,980 @@ -2078,7 +2078,7 @@ actually. Instance property on D, where I'm asking 416 00:22:38,380 --> 00:22:41,380 if it's signed is the minus sign, I'm just making this up, -我就把他变成正数 +我就把它变成正数 417 00:22:41,380 --> 00:22:43,820 @@ -2093,7 +2093,7 @@ But that would be an instance property or method and 419 00:22:47,920 --> 00:22:48,760 I would be sending it to D, -并且我会把他发给D +并且我会把它发给D 420 00:22:48,760 --> 00:22:52,260 @@ -2183,7 +2183,7 @@ they're really strongly associated with the class. So 437 00:23:52,820 --> 00:23:54,350 we put them as class methods, okay? -所以我们把他们放到类方法里面，好吗？ +所以我们把它们放到类方法里面，好吗？ 438 00:23:54,360 --> 00:23:58,090 @@ -4465,7 +4465,7 @@ Okay. So that's a very open-ended type. [LAUGH] Okay, 992 00:54:04,200 --> 00:54:07,400 -Swyft doesn't do things that way. Swyft is strongly typed. +Swift doesn't do things that way. Swift is strongly typed. 993 00:54:07,400 --> 00:54:12,140 @@ -4473,7 +4473,7 @@ Okay, it infers types but it's strongly typed. However, 994 00:54:12,140 --> 00:54:15,310 -Swyft has to work with all those IOSAPIs, so +Swift has to work with all those IOSAPIs, so 995 00:54:15,310 --> 00:54:17,080 @@ -4481,7 +4481,7 @@ it introduced this type called AnyObject. 996 00:54:17,080 --> 00:54:21,680 -So AnyObject in Swyft means A point or two an object of +So AnyObject in Swift means A point or two an object of 997 00:54:21,680 --> 00:54:24,680 @@ -4489,7 +4489,7 @@ unknown class, okay? It only works for objects for 998 00:54:24,680 --> 00:54:29,350 -classes not for. So it means the same thing as objective C. +classes not for structs. So it means the same thing as objective C. 999 00:54:29,360 --> 00:54:33,560 From 96d1bd68aaaca0d102161a15c883dd1adfaedbd2 Mon Sep 17 00:00:00 2001 From: saitjr Date: Wed, 15 Mar 2017 13:17:50 +0800 Subject: [PATCH 22/23] 8. Multithreading and Text Field has been finished (#58) * 1000~1200 * 1200~1300 * finish all --- .../8. Multithreading and Text Field.srt | 524 +++++++++++++++++- 1 file changed, 512 insertions(+), 12 deletions(-) diff --git a/subtitles/8. Multithreading and Text Field.srt b/subtitles/8. Multithreading and Text Field.srt index fe55ef7..98b11ee 100755 --- a/subtitles/8. Multithreading and Text Field.srt +++ b/subtitles/8. Multithreading and Text Field.srt @@ -5046,1996 +5046,2496 @@ even though it's loading those things in the background. 1010 00:52:53,638 --> 00:52:56,705 When they eventually arrive, it's gonna put them in the UI, +当图片下载完成后，便会在 UI 上显示， 1011 00:52:56,707 --> 00:53:00,109 okay. But while they're out there fetching I can do things +但在下载过程中， 1012 00:53:00,111 --> 00:53:06,882 like go back in my navigation controller. Make sense, +我可以做其他的操作，比如点击返回按钮等。看吧， 1013 00:53:06,884 --> 00:53:13,522 see that? >> [INAUDIBLE] +没问题。[清不清楚] 1014 00:53:13,524 --> 00:53:14,056 >> What happens, what? +什么事？怎么？ 1015 00:53:14,058 --> 00:53:14,857 >> [INAUDIBLE] Image each time +[听不清] 假设每次 1016 00:53:14,859 --> 00:53:17,560 you click out. >> So the question is, if I +都快速返回。那么，每次返回后， 1017 00:53:17,562 --> 00:53:20,596 click out, and then click back in, does it reload the image? +再点进去，会重新下载图片吗？ 1018 00:53:20,598 --> 00:53:22,831 And the answer is absolutely, because when I click out, +答案显而易见，因为再返回后， 1019 00:53:22,833 --> 00:53:26,068 -it throws that NBC out of the heap. Okay, it's gone. +it throws that MVC out of the heap. Okay, it's gone. +MVC 的堆内存就被销毁了，也就不存在了。 1020 00:53:26,070 --> 00:53:28,103 -Now actually, that NBC is not gonna immediately leave +Now actually, that MVC is not gonna immediately leave +但这次，MVC 却没有立即销毁， 1021 00:53:28,105 --> 00:53:30,773 the heap, cuz that closure that's doing the fetching is +因为闭包还在执行下载， 1022 00:53:30,775 --> 00:53:33,108 still holding it in the heap. But once that fetch comes +持有了该内存。当数据下载完成后， 1023 00:53:33,110 --> 00:53:36,779 back, then it'll leave the heap and the image with it. So +堆内存便销毁了，下载的图片也是。 1024 00:53:36,781 --> 00:53:40,583 yeah, every time we're re-fetching, okay? +所以，每次都是重新下载的，明白？ 1025 00:53:41,552 --> 00:53:41,684 So see how we built this nice responsive UI right now, okay? +这就是我们讲到的快速响应 UI。 1026 00:53:41,686 --> 00:53:45,221 Everybody got that? +大家都明白吗？ 1027 00:53:45,223 --> 00:53:48,090 Even though it's still taking a long time to fetch things, +即使数据下载依然需要很长时间， 1028 00:53:48,092 --> 00:53:51,493 we can still navigate. Now, what's a little weird about +但并不影响跳转。但是，UI 还有些 1029 00:53:51,495 --> 00:53:54,330 this UI, though, is that while it's fetching, +不足，在数据下载时， 1030 00:53:54,332 --> 00:53:57,633 like when I'm here, it's not clear what's going on. +比如这个界面，并不知道它在处理什么。 1031 00:53:57,635 --> 00:53:59,168 It looks like there's just no Earth image, +这里好像并没有 Earth 的图片， 1032 00:53:59,170 --> 00:54:02,171 I guess. I don't know, I guess not, I don't see it. Wouldn't +我也不知道，可能是吧，什么都看不见。如果 1033 00:54:02,173 --> 00:54:04,840 it be cool if we could give some feedback to the user? +能给用户一个标识不是更好吗？ 1034 00:54:04,842 --> 00:54:08,544 Hey, I'm working on it, okay, this image is big. +Hey，我正在努力加载呢，图片太大了。 1035 00:54:08,546 --> 00:54:09,545 All right, and we can do that. +是的，我们可以处理。 1036 00:54:09,547 --> 00:54:12,414 And the cool way to do that is with a little spinner, okay, +可以在这里加个指示器， 1037 00:54:12,416 --> 00:54:15,651 a little animating. You see them all in apps little thing +一个小动画。在很多 app 中都能看到 1038 00:54:15,653 --> 00:54:17,886 that spins around basically telling him yeah, yeah, +指示器，告知系统收到了交互， 1039 00:54:17,888 --> 00:54:20,789 I know, I'm working on it. So let's put a spinner in there. +正在进行处理。那么，让我们在这里加上指示器吧。 1040 00:54:20,791 --> 00:54:24,059 Turns out to be really easy to put, do spinners in iOS. +在 iOS 中加指示器，真的非常简单。 1041 00:54:24,061 --> 00:54:26,395 We're just gonna go to the storyboard, okay. +打开 storyboard， 1042 00:54:26,397 --> 00:54:30,232 I'm gonna put the spinner here in this view. Now when I put +将指示器加到这个 view 中。但注意， 1043 00:54:30,234 --> 00:54:32,167 it in there, I'm gonna have to be very careful. +加进去要非常小心。 1044 00:54:32,169 --> 00:54:32,501 And this is a good chance for +正好给大家 1045 00:54:32,503 --> 00:54:35,004 me to show you more about the document outline. But +详细演示下 document outline。 1046 00:54:35,006 --> 00:54:38,140 watch this, so I'm gonna go down here. The spinner is just +看这里，滚到这里，有个可以直接 1047 00:54:38,142 --> 00:54:40,509 a thing you can drag out. You see it right here. +进行拖拽的指示器。就是这个。 1048 00:54:40,511 --> 00:54:42,544 Now watch what happens when I drag this out, okay, and +将它拖到界面中， 1049 00:54:42,546 --> 00:54:46,215 I try to use the blue lines to put it in the middle, drop it. +蓝色辅助线可帮助居中，就扔到这。 1050 00:54:46,217 --> 00:54:48,784 It looks like, okay, that worked, that's nice. +看起来不错，正是我们需要的。 1051 00:54:48,786 --> 00:54:50,786 I can even go here and inspect it up here. +还可以打开上面的 inspect， 1052 00:54:50,788 --> 00:54:54,123 You see, I can make a nice larger one. Maybe I'll even +这里，可以选择更大的样式。也可以 1053 00:54:54,125 --> 00:54:58,594 make it blue instead of white. Let's have it hide itself +将其改为蓝色。还可以设置 1054 00:54:58,596 --> 00:54:59,595 when it stops animating. +动画停止时，自动隐藏。 1055 00:54:59,597 --> 00:55:01,597 We can do all kinds of cool stuff here. But +这里可以设置很多属性。 1056 00:55:01,599 --> 00:55:04,400 actually something terrible has happened, +但同时引发了一个问题， 1057 00:55:04,535 --> 00:55:06,869 which is that when I dragged that thing out and +在我将控件拖出来， 1058 00:55:06,871 --> 00:55:08,037 dropped it in the middle there, +然后放置到中间时， 1059 00:55:08,039 --> 00:55:11,173 it made it a subview of the Scroll View, okay? +这个控件变成了 Scroll View 的子视图。 1060 00:55:11,175 --> 00:55:14,877 In the interface builder when you drag a view out on top of +在 interface builder 中，如果将一个控件拖到 1061 00:55:14,879 --> 00:55:16,578 another view, it makes it a subview of that. +另一个控件上，那该控件就成了另一个的子视图。 1062 00:55:16,580 --> 00:55:19,148 Now you can't really tell that here, but that's what this +直接从这里不大看的出来， 1063 00:55:19,150 --> 00:55:21,483 little guy over in the corner, the document outline, +要点击角落里的这个小按钮，打开 document outline， 1064 00:55:21,485 --> 00:55:24,353 is really great at. If you look at the document outline, +这非常棒，在 document outline 中， 1065 00:55:24,355 --> 00:55:27,189 do you see how the activity indicator is indented +能看到 activity indicator 在 1066 00:55:27,191 --> 00:55:30,893 from the Scroll View? Okay, that means it's a subview +Scroll View 中吗？这就意味着，它成为了 1067 00:55:30,895 --> 00:55:34,496 of the Scroll View. Now, if you don't want that, okay, +Scroll View 的子视图。如果你不想这样， 1068 00:55:34,498 --> 00:55:36,665 no problem. You can just drag it up above. +没问题，将它拖到上面。 1069 00:55:36,667 --> 00:55:39,568 Now, it's not a subview of the Scroll View. Now, of course, +现在，它就不再是 Scroll View 的子视图了。当然， 1070 00:55:39,570 --> 00:55:41,804 it's not in the right order right now, because I want this +这还不是正确的视图层级，因为我想要指示器 1071 00:55:41,806 --> 00:55:44,340 thing to be in front of the Scroll View. So, I'm gonna put +放在 Scroll View 前面。所以，要把 1072 00:55:44,342 --> 00:55:47,643 the Scroll View on top of it. So, now they're siblings, and +Scroll View 移到指示器上面。现在，它们就在一个层级了，并且 1073 00:55:47,645 --> 00:55:51,447 this one is in front, because remember, the subview is list, +这个再上面，记住，子视图是链表， 1074 00:55:51,449 --> 00:55:52,681 the top ones are in the back. +越在后面，层级越高。 1075 00:55:52,683 --> 00:55:54,650 The other ones go towards the front. So, +升序排列。所以， 1076 00:55:54,652 --> 00:55:58,020 now we have this thing in the front, okay? Now, +现在这个就在前面了。 1077 00:55:58,022 --> 00:56:00,522 another thing is, what if I wanna have, +还有个问题，如果我想， 1078 00:56:00,524 --> 00:56:03,359 constraints on this to keep this in the middle? +想要给该空间加约束，是它一直居中，该怎么办？ 1079 00:56:03,361 --> 00:56:05,060 Well, I have to be very careful here too, +这一步同样需要仔细。 1080 00:56:05,062 --> 00:56:08,230 cuz those dashed lines. We're referring to the scroll view. +因为这里的约束，都是与 scroll view 关联的。 1081 00:56:08,232 --> 00:56:11,033 So if I tried to do reset to suggested constraints here, +所以，先要重置默认的约束， 1082 00:56:11,035 --> 00:56:13,869 I'm gonna get constraints that constrain the activity +会发现现在 activity indicator 1083 00:56:13,871 --> 00:56:16,205 indicator to the scroll view. I don't want that. +的约束都是基于 scroll view 的，我可不想这样。 1084 00:56:16,207 --> 00:56:19,575 I want the activity indicator to be in the middle of its +我希望 activity indicator 相对其父视图 1085 00:56:19,577 --> 00:56:19,842 superview. +居中。 1086 00:56:19,844 --> 00:56:23,612 And watch this, you can do control drag in the document +看仔细了。你可以在 document outline 中， 1087 00:56:23,614 --> 00:56:26,782 outline. So I'm gonna control drag from my activity +按住 control。从 activity indicator 这里， 1088 00:56:26,784 --> 00:56:30,919 indicator to its superview in the document outline, +按住 control，拖到 document outline 中的父视图上， 1089 00:56:30,921 --> 00:56:33,255 not over here, but in the document outline. +不是这，是在 document outline 中。 1090 00:56:33,257 --> 00:56:35,758 And when I let go, I can do things like, yeah, +松开鼠标，可以看到这个，是的， 1091 00:56:35,760 --> 00:56:41,764 please center it vertically and horizontally in yourself. +请在水平与竖直方向都居中。 1092 00:56:41,766 --> 00:56:46,568 Okay? So now this thing is centered and middle. Okay? +那么，现在就居中了。 1093 00:56:46,570 --> 00:56:50,939 So, now we've got the spinner, how do we do anything with it? +至此指示器就创建好了，那应该怎么处理逻辑呢？ 1094 00:56:50,941 --> 00:56:51,440 Well, we need an outlet to it. +现在需要一个它的 outlet。 1095 00:56:51,442 --> 00:56:55,511 So, I'm going to bring out my code over here, okay? +把代码显示出来， 1096 00:56:55,513 --> 00:56:56,712 Do it automatic. +自动关联文件。 1097 00:56:56,714 --> 00:56:59,681 Got our image view controller here, let's give it to this, +这是 image view controller。关掉这个， 1098 00:56:59,683 --> 00:57:02,851 give it to that, give it some room. Okay so +关掉这个，腾点空间出来。好的， + 1099 00:57:02,853 --> 00:57:05,721 I'm just going to create an outlet from this little +将指示器从这拖到这， 1100 00:57:05,723 --> 00:57:10,125 spinner right here, over here. See it make sure that it's +创建 outlet。注意这里的类型 1101 00:57:10,127 --> 00:57:13,796 type is activity indicator view not something else, and +是 activity indicator，而不是别的。 1102 00:57:13,798 --> 00:57:14,730 I'm just going to call it spinner, +名字就叫 spinner 吧， 1103 00:57:14,732 --> 00:57:17,499 I like spinner as my name. And it's just an outlet, +我喜欢 spinner 这个名字，这是个 outlet， 1104 00:57:17,501 --> 00:57:20,769 it's a normal outlet just like our scroll view or anything +非常普通的 outlet，和 scroll view 或其他 outlet 1105 00:57:20,771 --> 00:57:23,272 else is an outlet. Okay just like your display was in your +没区别。就像计算器能显示一样， 1106 00:57:23,274 --> 00:57:27,643 calculator there's nothing particularly special about it. +没什么特别的。 1107 00:57:27,645 --> 00:57:31,413 So now that we have this nice spinner right here, +现在，我们拿到了指示器变量， 1108 00:57:31,415 --> 00:57:34,450 we just need to turn it on and turn it off. So where are we +只需要控制它的开始与结束。那什么时候开始呢？ 1109 00:57:34,452 --> 00:57:37,352 gonna turn it on? Well, I'm gonna turn it on right before +我觉得它应该在其他线程开始 1110 00:57:37,354 --> 00:57:41,023 I start doing something on that other thread, okay. So +处理事情的时候开始。 1111 00:57:41,025 --> 00:57:44,493 right here when I dispatch onto this other thread to go +就是这里，在将处理 NSData 的 block 派发到 1112 00:57:44,495 --> 00:57:47,629 do this NSData, which is gonna block, I'm just gonna say +其他线程的时候，让 1113 00:57:47,631 --> 00:57:53,435 spinner startAnimating. And I'm gonna be even trickier and +spinner startAnimating。我准备在这里增加点难度， 1114 00:57:53,437 --> 00:57:56,972 go spinner?.startAnimating just in case +改为 spinner?startAnimating，防止 1115 00:57:56,974 --> 00:58:00,776 I'm fetching my image like as a result of prepare for +在 prepare for segue 的时候 1116 00:58:00,778 --> 00:58:03,846 segue, okay, because there my outlets aren't set. +调用该方法获取图片，而这个时候，outlet 还未创建。 1117 00:58:03,848 --> 00:58:05,747 So even if my app spinner's not set, +这样的话，在 spinner 还没创建时， 1118 00:58:05,749 --> 00:58:09,751 I'll just do nothing. Now where do I wanna turn it off? +没有任何响应就行。那应该在何时停止呢？ 1119 00:58:09,753 --> 00:58:11,954 Its actually two places that you can turn this off. +应该有两处地方需要停止。 1120 00:58:11,956 --> 00:58:16,892 One good place might be down here when your image gets set. +一处是在图片加载完成后。 1121 00:58:16,894 --> 00:58:18,994 Okay? Cuz if someone sets your image, +在图片加载完成后， 1122 00:58:18,996 --> 00:58:23,198 then you don't need to be spending anymore. +spinner 就没必要显示了。 1123 00:58:23,367 --> 00:58:25,434 By definition, you're showing the image. +理论上，这里图片都已经展示了。 1124 00:58:25,436 --> 00:58:29,004 So, it will make no sense to be spinning such a good place. +所以，spinner 已经完成使命了。 1125 00:58:29,006 --> 00:58:31,106 Got to be a little careful though here because, +另外一个地方需要特别小心， 1126 00:58:31,108 --> 00:58:34,109 what happens when we get in here, okay? +这里会出现什么情况呢， 1127 00:58:34,111 --> 00:58:36,378 And you get to the URL here, and +这里是获得 URL， 1128 00:58:36,380 --> 00:58:38,647 the image data wasn't able to be found, so +如果 URL 未找到图片数据， 1129 00:58:38,649 --> 00:58:41,583 you never call set image, so it's never going to stop. +图片就无法创建，那指示器就一直没停止。 1130 00:58:41,585 --> 00:58:45,387 So you probably want to put in else spinner stop animating +所以这里也需要加上 spinner 停止的代码。 1131 00:58:45,389 --> 00:58:48,490 here as well. Okay so this is gonna stop the spinner in +所以， spinner 就会在 1132 00:58:48,492 --> 00:58:52,094 the case where it went off to the Internet to get something, +无网络，或者未找到数据的情况下， 1133 00:58:52,096 --> 00:58:55,030 and it couldn't find it. Okay, eh, +停止。哦， 1134 00:58:55,032 --> 00:59:00,969 little tricky. Okay, so let's see how that works. +小失误。好，运行看看效果。 1135 00:59:06,644 --> 00:59:08,810 Alright, here we go, let's try Earth, there it is, +跑起来了，打开 Earth，对，没错， 1136 00:59:08,812 --> 00:59:11,513 it's spinning, and we can go back, let's try Cassini, it's +有指示器了，点击返回，打开 Cassini，也有 1137 00:59:11,515 --> 00:59:15,484 spinning. Now when Cassini appears it stops spinning, and +指示器。在 Cassini 加载完后，指示器停止， 1138 00:59:15,486 --> 00:59:19,354 so it hides because we had, we set this switch over here +并且自动消失，因为我们之前字 inspect 中， 1139 00:59:19,356 --> 00:59:23,158 on this one we inspected it called hides when stopped, +将它设置为停止就自动隐藏， 1140 00:59:23,160 --> 00:59:28,196 right. And so since it hides when stopped, it's not here +没问题。所以，在停止后，指示器 1141 00:59:28,198 --> 00:59:32,734 anymore okay. [INAUDIBLE] Saturn, +就不见了。[听不清] Saturn， 1142 00:59:32,736 --> 00:59:38,974 spins okay then we can rotate. Big image, taking a long time. +旋转屏幕。是个大图，需要更长的时间。 1143 00:59:38,976 --> 00:59:43,312 There it is, okay? So see how we turn this into an app, it's +完成，没问题。这就是在 app 中的运用， 1144 00:59:43,314 --> 00:59:45,948 really responsive and really nice and it's being as fast as +非常友好，非常漂亮，说多快有多快。 1145 00:59:45,950 --> 00:59:47,983 it can. It's getting those images as fast as it can, +图片现在说多快有多快， 1146 00:59:47,985 --> 00:59:51,153 but from the user standpoint, it's very responsive. +从用户的角度来说，也非常友好。 1147 00:59:51,155 --> 00:59:53,288 You really wanna go with that way. +大家以后也应该这样做。 1148 00:59:53,290 --> 00:59:57,326 Okay, so now I'm gonna show two unrelated to this, okay? +接下来，我将提到两个不相关的东西。 1149 00:59:57,328 --> 01:00:01,697 But did you've asked about in Piazza. One is notice that +大家对 Piazza 有以为吗。在运行的时候， 1150 01:00:01,699 --> 01:00:07,235 when we run this, let's run again, watch what happens. +重新运行下，看看出了什么问题。 1151 01:00:07,972 --> 01:00:14,009 When we run, we get an empty image view controller +在运行起来时，image view controller 是空的， 1152 01:00:14,011 --> 01:00:17,012 which really doesn't make any sense. What we'd +而这不应该出现才对。我们想要的是， 1153 01:00:17,014 --> 01:00:19,848 really want it to, when we first run and this is empty, +在第一次运行的时候，这是空的， 1154 01:00:19,850 --> 01:00:23,251 we want it to come up showing this view controller. So +而我们想要的是展示这个 controller。 1155 01:00:23,253 --> 01:00:24,152 this is like with your calculator, +这和之前的计算器项目类似， 1156 01:00:24,154 --> 01:00:25,921 you don't want it to come up showing empty graph. +我们不想展示空的界面。 1157 01:00:25,923 --> 01:00:28,857 You want it to come up showing the calculator because +空界面什么用都没有，应该展示 1158 01:00:28,859 --> 01:00:29,391 the empty graph is useless, +计算器界面才对。 1159 01:00:29,393 --> 01:00:32,394 it just forces them to do that back thing right here for +这个还必须要手动返回，而且 1160 01:00:32,396 --> 01:00:35,931 no good reason. Okay, so how do we do that, okay this is +还不知道为什么要这样。那么，该怎么处理呢， 1161 01:00:35,933 --> 01:00:38,367 another case where we need to use delegation. +这是另个需要用到 delegation 的原因。 1162 01:00:38,369 --> 01:00:43,105 -In this case it's the split fuse delegate. Okay, split +In this case it's the split view delegate. Okay, split +这里要用到的是 split view delegate。split 1163 01:00:43,107 --> 01:00:45,407 view controller's delegate. So what does this code look like? +view controller 的 delegate。那代码该怎么写呢？ 1164 01:00:45,409 --> 01:00:48,143 I'm gonna put this in Cassini, view controller right here. +我准备把代码放在 Cassiini view controller 的这个地方。 1165 01:00:48,145 --> 01:00:51,113 The first thing I need to do is I need to make the Cassini +首先，我准备，我准备将 Cassini view controller 设为 1166 01:00:51,115 --> 01:00:55,150 view controller be its own split view's delegate. +split view 的 delegate。 1167 01:00:55,152 --> 01:00:57,052 In other words, it needs to be the delegate of +也就是说，它需要成为 1168 01:00:57,054 --> 01:00:57,319 the split view it's in. +split view 的代理。 1169 01:00:57,321 --> 01:01:01,156 So I'm gonna do this in viewDidLoad. Okay sometimes +我准备在 viewDidLoad 里面处理。 1170 01:01:01,158 --> 01:01:03,525 viewDidLoad is not quite early enough to do things for +在 viewDidLoad 中，获取 split view 才 1171 01:01:03,527 --> 01:01:07,462 split views. We might have to do it in a wait for even. But +不算太早。别的方法可能还要判断时机，而 1172 01:01:07,464 --> 01:01:10,165 -this will work in beaded load. And I'm just going to set +this will work in viewDidLoad. And I'm just going to set +viewDidLoad 就不用。我准备在这里设置 1173 01:01:10,167 --> 01:01:14,136 my split view controllers remember MVC knows the split +split view controller，每个 MVC 能拿到 split 1174 01:01:14,138 --> 01:01:16,872 view controller its in. Or the navigation controller its in, +view controller 变量。Navigation controller 也可以， 1175 01:01:16,874 --> 01:01:18,106 or the tab bar controller its in. So +tab bar controller 也行。 1176 01:01:18,108 --> 01:01:22,611 SplitViewController says what it is, might be nil, okay? But +而 splitViewController 也可能为空， 1177 01:01:22,613 --> 01:01:25,514 if it's not I'm gonna set its delegate to be myself. +如果不为空，则设置 self 为 delegate。 1178 01:01:25,516 --> 01:01:29,284 Of course as soon as I do this I'm getting an error because +当然，这样处理会出现错误， 1179 01:01:29,286 --> 01:01:32,954 I didn't say that I was a UI SplitViewController delegate. +因为 self 还未遵循 UISplitViewControllerDelegate。 1180 01:01:32,956 --> 01:01:33,822 So I need to go up here and +滚动到顶部， 1181 01:01:33,824 --> 01:01:37,793 say that I'm a UI SplitViewController delegate. +声明 self 遵循 UISplitViewControllerDelegate。 1182 01:01:39,096 --> 01:01:43,365 All right that satisfies that error. All is good. Now which +好的，错误解决了。没问题，那么， 1183 01:01:43,367 --> 01:01:46,668 split view controller method am I going to implement? +应该实现 split view controller 的哪个方法呢？ 1184 01:01:46,670 --> 01:01:49,538 Okay hold on your chairs for this one, okay +抓紧椅子，别被吓到了。 1185 01:01:49,540 --> 01:01:52,007 by the way again on the split view controller delegate so +因为已经遵循 split view controller delegate，所以 1186 01:01:52,009 --> 01:01:54,142 I can just start typing split view and you can see it +键入 split view 就可以索引出方法，看吧， 1187 01:01:54,144 --> 01:01:56,678 shows me all the split view controller delegate methods. +这些，全都是 split view controller delegate 的方法。 1188 01:01:56,680 --> 01:01:59,781 There's quite a few. Okay about a dozen of them. +有很多方法，大概十多个。 1189 01:01:59,783 --> 01:02:02,918 And the one I want is the one that controls +而我需要的那个， 1190 01:02:02,920 --> 01:02:07,222 the collapsing of the detail on top of the master. +是可以控制 detail 压缩的方法。 1191 01:02:07,224 --> 01:02:10,058 Because I don't want it to collapse that detail on top of +因为在 detail 没有数据时，不需要将 1192 01:02:10,060 --> 01:02:13,595 the master if the detail is empty, okay? +detail 显示出来。 1193 01:02:13,597 --> 01:02:14,429 If it doesn't have an image in there, +如果没有图片， 1194 01:02:14,431 --> 01:02:17,666 I don't want it to do that. So this thing that controls that +就不需要显示。这个方法叫做， 1195 01:02:17,668 --> 01:02:22,738 -it's called, collab secondary view controller, +it's called, called secondary view controller, +叫做 secondary view controller， 1196 01:02:22,740 --> 01:02:26,708 -on to primary compute controller. Okay, collab +on to primary view controller. Okay, called +on to primary view controller。 1197 01:02:26,710 --> 01:02:29,511 -secondary view controller, on to primary compute controller. +secondary view controller, on to primary view controller. +secondary view controller，on to primary view controller。 1198 01:02:29,513 --> 01:02:32,748 Now, notice it returns a Bool, this Bool +注意，返回值为 Bool，如果 1199 01:02:32,750 --> 01:02:35,650 you return true if you took care of this. +返回 true，就是自行处理。 1200 01:02:35,652 --> 01:02:40,589 Return false if you want the system to do the collapse. +如果返回 false，表示交由系统处理。 1201 01:02:40,591 --> 01:02:43,492 Okay, so this is a way where the delegate can do this +那么，这个代理方法就是用来处理 1202 01:02:43,494 --> 01:02:44,726 collapse if it wants, or not, and +是否需要压缩的， 1203 01:02:44,728 --> 01:02:47,629 it just lets the split view know whether it did it or not. +而且，只是告知 split view 是否需要。 1204 01:02:47,631 --> 01:02:50,232 So that's what the bool is, let it know when it did it. +这就是这个 bool 值的作用，用于告知 split 的。 1205 01:02:50,234 --> 01:02:53,568 So, this is actually quite simple right here. +那这样就非常简单了。 1206 01:02:53,570 --> 01:02:56,738 We just want to get the image view controller, +我么只想获得 image view controller， 1207 01:02:56,740 --> 01:03:00,675 okay? Well first of all let's make sure that the primary +首先判断 primary view controller 1208 01:03:00,677 --> 01:03:05,881 view controller, content view controller, is ourself. +的 content view controller 是 self。 1209 01:03:05,883 --> 01:03:08,083 Now it should be, because we're setting ourselves +这个应该是没问题的，因为我们之前将 self 1210 01:03:08,085 --> 01:03:09,718 as our own split view delegate, so we should be +设为了 split view controller 的 delegate，所以 1211 01:03:09,720 --> 01:03:13,188 the primary view controllers, the masters content Okay? +self 应该是 primary view controller 的 master content。 1212 01:03:13,190 --> 01:03:16,658 So we showed you that, that should not be a problem. But +所以写的这个判断，是能成功的。 1213 01:03:16,660 --> 01:03:20,896 now I'm gonna say, on top of that, if I can let ivc = +接下来，在括号中写，if let ivc = 1214 01:03:20,898 --> 01:03:24,633 the secondaryViewController, that's the detail. +secondaryViewController，即 detail 页面， 1215 01:03:24,635 --> 01:03:30,238 It contentViewController as an ImageViewController. Okay? So, +的 contentViewController，并强转为 ImageViewController。也就是说， 1216 01:03:30,240 --> 01:03:36,011 if have a ImageViewController as my detail, and +如果 detail 是 ImageViewController，然后 1217 01:03:36,013 --> 01:03:39,281 where, everyone know about where, right? You did your +where，where 大家应该都知道吧？如果做了 1218 01:03:39,283 --> 01:03:41,783 reading assignments, you know about where. Where is +预习，那应该是没问题的。 Where 是 1219 01:03:41,785 --> 01:03:44,686 an additional clause that you can add onto an if, okay? +可以加载 if 之后的从句。 1220 01:03:44,688 --> 01:03:47,856 So I'm gonna say where the image view controllers +继续写，wherer image view controller 1221 01:03:47,858 --> 01:03:52,828 image URL is nil. So if I have an image view controller as +的 image URL 是 nil。也就是说，如果 image view controller 是 1222 01:03:52,830 --> 01:03:58,166 my detail and it's, image url is nil, then it's empty. +detail，并且图片的 url 为 nil，那界面就是空的。 1223 01:03:58,168 --> 01:03:59,968 There's nothing in there. There's no Saturn or +什么内容都没有，没有 Satrun 图片或 1224 01:03:59,970 --> 01:04:03,638 anything else. So in this case I'm going to return true, +别的内容。这种情况下，就返回 true， 1225 01:04:03,640 --> 01:04:05,874 which is me telling the system, yeah, +即告知系统， 1226 01:04:05,876 --> 01:04:08,710 I took care of that. Okay, I put that detail, I collapsed +我自己处理。我自己设置 detail，自己对 1227 01:04:08,712 --> 01:04:11,079 that detail on top of the master, don't worry about it. +master 上的 detail 进行处理，你不用管。 1228 01:04:11,081 --> 01:04:13,982 Now I didn't, didn't actually do anything, that's good, +而在这里，我什么都没做，这很好， 1229 01:04:13,984 --> 01:04:16,017 cuz that's what I want. I don't want that +我就想这样。因为我并不想 1230 01:04:16,019 --> 01:04:18,753 detail to be collapsed on top of the master if the thing is +在内容是空时，master 顶部的 detail 被压缩。 1231 01:04:18,755 --> 01:04:22,357 nil. All right, so I just kind of lied to the system and told +所以，这里是在骗系统，说 1232 01:04:22,359 --> 01:04:26,328 them I handled it when in fact I didn't. Okay, otherwise, +我要自行处理，但实际上，我什么都没做。好的，除此之外， 1233 01:04:26,330 --> 01:04:29,431 we're just gonna let the system do whatever it does, +别的情况就需要系统处理了。 1234 01:04:29,433 --> 01:04:33,902 okay. Return false, we did not handle this so you handle it. +返回 false，表示我自己不处理，你来处理吧。 1235 01:04:33,904 --> 01:04:41,543 Okay, so let's see if that works. Okay, so here it is, +接下来，看看效果吧。好的， 1236 01:04:41,545 --> 01:04:46,615 look at that. It came up, didn't show me a blank thing, +你看，没有再展示空白的页面了， 1237 01:04:46,617 --> 01:04:51,319 so it worked. Now let's click on one of these. Woop, okay, +成功了。点击其中一个， 1238 01:04:51,321 --> 01:04:51,486 it worked. So +没问题。 1239 01:04:51,488 --> 01:04:54,789 it collapsed the secondary on top of the primary when I +能在我需要的时候，将 primary 顶部的 secondary 1240 01:04:54,791 --> 01:04:58,026 wanted it too, okay? But if it came up nil, +压缩。当回来为空的时候， 1241 01:04:58,028 --> 01:05:01,229 then it didn't show it. Everyone understand that? I +就不会再显示。都能听懂吗？ 1242 01:05:01,231 --> 01:05:03,899 know it seems a little, a lot of long words in here [LAUGH] +我知道这个方法很长 「笑」 1243 01:05:03,901 --> 01:05:06,501 like primary view controller, secondary view controller, but +又是 primary view controller，又是 secondary view controller 的， 1244 01:05:06,503 --> 01:05:09,871 this is just master in detail, that's all this is. And +其实就是 master 和 detail，没什么奇怪的。 1245 01:05:09,873 --> 01:05:12,040 we're just checking where the image URL's nil and just +而这里是检查 image 的 URL 是否为空，然后 1246 01:05:12,042 --> 01:05:14,809 returning that, we handled it when we really didn't handle +返回这个，理论上需要我们处理，但实际没有， 1247 01:05:14,811 --> 01:05:18,013 it because we don't want it handled. Okay. One other +因为这本身就不需要处理什么。另外一个问题是， 1248 01:05:18,015 --> 01:05:24,252 thing I want to show you is reusing the detail in iPad. +在 iPad 上重用 detail 的情况。 1249 01:05:25,856 --> 01:05:31,326 Look at iPad. And we have the master detail right here. +看看 iPad。这是 master detail。 1250 01:05:31,328 --> 01:05:35,363 Every time we click on this thing, it's creating a new MVC +每次点击的时候，会创建新的 MVC。 1251 01:05:35,365 --> 01:05:39,334 here. Okay? Creating a brand new MVC. And if there, +创建一个全新的 MVC。但对此， 1252 01:05:39,336 --> 01:05:41,102 there's really no reason for that. Okay? +其实完全没必要。 1253 01:05:41,104 --> 01:05:45,373 We could absolutely just reuse this MVC right here. +完全可以对 MVC 进行重用。 1254 01:05:45,375 --> 01:05:47,842 Okay, we don't have to create a new one every time. +我们不需要每次都创建新的。 1255 01:05:47,844 --> 01:05:50,979 So, how would we do that? How would we reuse this? +那么，该怎么办呢？如何重用呢？ 1256 01:05:50,981 --> 01:05:54,182 Well, if we're gonna reuse this, we can't use +如果想要重用这个，就不能用 1257 01:05:54,184 --> 01:05:57,385 segues because segues always create a new MVC. +segue，因为 segue 每次都会创建新的 MVC。 1258 01:05:57,387 --> 01:05:59,254 That's what segues do, they create a new MVC. +这就是 segue 在做的事情，创建新的 MVC。 1259 01:05:59,256 --> 01:06:02,390 So, we can't use segues, okay, to do that in that case. So, +所以，这种情况下，我们不能用 segue。那么， 1260 01:06:02,392 --> 01:06:06,761 lets go back to our Cassini right here. Our, storyboard. +回到 Cassini 项目。看到 storyboard。 1261 01:06:06,763 --> 01:06:11,800 And we're not going to use these segues over here. Okay, +我们不再使用这里的 segue。 1262 01:06:11,802 --> 01:06:14,069 see these three segues? I'm gonna get rid of them. +看到这三个 segue 了吗？我准备把它们去掉。 1263 01:06:14,071 --> 01:06:16,671 Get rid of, oops, not that. Click here, +都去掉，哦，点错了。点这个， 1264 01:06:16,673 --> 01:06:16,738 get rid of that one, +去掉它。 1265 01:06:16,740 --> 01:06:18,940 I'm gonna get rid of that one, I'm gonna get rid of that one. +去掉这个，去掉这个。 1266 01:06:18,942 --> 01:06:20,442 Cuz I cannot segue from these buttons or +我不打算将 button 与 segue 关联了， 1267 01:06:20,444 --> 01:06:24,446 it will constantly create a new one of these details. +因为它每次都会创建新的 detail。 1268 01:06:24,448 --> 01:06:26,781 Instead, what I'm gonna do is to use target action. +而我准备用 target-action 来实现。 1269 01:06:26,783 --> 01:06:30,952 So I'm just gonna bring up my code here, some space, +接着，打开 diamante，腾点空间， 1270 01:06:30,954 --> 01:06:34,289 all right, and I'm gonna do a target action message from +好的，我会给每个按钮都添加 1271 01:06:34,291 --> 01:06:38,626 each of these that reuses the detail to show the image. +target-action，用于重用显示 image 的 detial。 1272 01:06:38,628 --> 01:06:41,529 So let's do that. Let's just go Ctrl+drag here. +那么，开始吧。按住 Ctrl 并拖到这里， 1273 01:06:41,531 --> 01:06:44,332 I'm gonna call this show image, that's a good name for +名字就叫 showimage，作为事件的名字 1274 01:06:44,334 --> 01:06:47,602 this action right here, and I'm gonna have UI button +还挺合适， 事件的 sender 是 1275 01:06:47,604 --> 01:06:50,505 -be the center, cuz I'm gonna know which one to show because +be the sender, cuz I'm gonna know which one to show because +UIButton，因为我需要通过按钮 1276 01:06:50,507 --> 01:06:52,640 I'm gonna look at the sender. Okay. So, +判断应该显示哪一个。Okay， 1277 01:06:52,642 --> 01:06:54,909 I got show image right here. So, let's go ahead and +showimage 方法创建好了。接下来， 1278 01:06:54,911 --> 01:06:56,978 put the code here. So, show image is a lot like, +就是填充代码了。showimage 的处理， 1279 01:06:56,980 --> 01:07:00,448 looks a lot like prepare for seg, segue. We can only do +和 prepareforsegue 中的代码类似。只能在 1280 01:07:00,450 --> 01:07:04,119 this if we're in a split view. Right, we can only do the show +split view 中这样做，这样来 1281 01:07:04,121 --> 01:07:07,555 image thing here, this trick, if we are in a split view, +显示 image，如果在 split view 中， 1282 01:07:07,557 --> 01:07:11,192 sorry, let me, just so we can see what's going on here. +啊，不好意思，这里可以看到。 1283 01:07:11,194 --> 01:07:14,129 All right. Okay, we can only do a split view so +因为只能在 split view 中使用， 1284 01:07:14,131 --> 01:07:17,098 I'm gonna first check to see that. I'm gonna say, +所以首先判断， 1285 01:07:17,100 --> 01:07:21,836 if I can let the ivc = splitViewControllers, +if let ivc = splitViewController， 1286 01:07:21,838 --> 01:07:24,773 if I have one, view Controller, +如果存在，viewcontrollers， 1287 01:07:24,775 --> 01:07:29,110 controller[1]. We know that's the detail, right. +controller[1]，我们知道这个是 detail， 1288 01:07:29,112 --> 01:07:30,478 And actually I don't wanna use sub one +但这里我不想用下标取值， 1289 01:07:30,480 --> 01:07:33,248 because if for some reason my split view controller +如果某些情况下，split view controller 1290 01:07:33,250 --> 01:07:36,217 doesn't have a detail, then view controllers only have one +没有 detail，那么 viewcontrollers 就只有 1291 01:07:36,219 --> 01:07:39,721 thing so I'm actually gonna use ViewController.last. +一个值，所以我准备用 viewcontroller.last 取值。 1292 01:07:39,723 --> 01:07:43,258 Okay, because last returns nil if there's no such thing. +如果 last 返回空，则说明什么都没有。 1293 01:07:43,260 --> 01:07:46,227 Okay, and then I'm gonna grab the content view controller as +接下来，判断 content view controller 1294 01:07:46,229 --> 01:07:49,264 always and I'm gonna check to see if that's an image view +是否是 image view controller，这和之前差不多， 1295 01:07:49,266 --> 01:07:50,765 controller. So in other words, +也就是说， 1296 01:07:50,767 --> 01:07:53,134 if I can get my detail as an image view controller, +如果 detail 是 image view controller， 1297 01:07:53,136 --> 01:07:56,271 then I'm basically gonna do this right here, +就可以走这段逻辑，拷贝过来， 1298 01:07:56,273 --> 01:07:59,507 in here, but here I don't have to say sender as UI button +这里并不需要将 sender 转换为 UIButton， 1299 01:07:59,509 --> 01:08:00,008 because the sender is +因为 sender 本来就是 1300 01:08:00,010 --> 01:08:02,177 a UI button so I can just say sender and +UIButton，而且 sender 在这里 1301 01:08:02,179 --> 01:08:06,614 it's never gonna be nil there. Okay? And do that. So see, +也不可能为空。Okay？就这样。 1302 01:08:06,616 --> 01:08:09,384 see what's going on here? So no segueing, +这里在干嘛呢？没有了 segue， 1303 01:08:09,386 --> 01:08:16,825 I'm not doing any segueing. So when I go over here, Okay, +不再需要 segue 了。继续运行， 1304 01:08:16,827 --> 01:08:20,762 and I pick something, like Cassini, or Earth, okay, +点击按钮，比如 Cassini，或者 Earch， 1305 01:08:20,764 --> 01:08:25,767 we'll say. It loads it up. Actually, +就可以看到，正在加载。实际上， 1306 01:08:25,769 --> 01:08:28,236 we got to do one other thing, sorry. Back here, in our +我们忘了点东西，不好意思，回到程序， 1307 01:08:28,238 --> 01:08:31,673 storyboard, let's wire up all these buttons to do that. +在 storyboard 中，应该给所有 button 添加事件。 1308 01:08:31,675 --> 01:08:35,977 [LAUGH] Okay, we only wired up earth to do this show image so +[笑] Okay，现在只是给 earth 关联了 showimage，所以， 1309 01:08:35,979 --> 01:08:39,080 let's do that. Let's go to automatic. +来处理其余的，选择 automatic。 1310 01:08:39,583 --> 01:08:40,415 All right, so let's control, +关联这个， 1311 01:08:40,417 --> 01:08:42,750 so this one here and let's wire up this one here. Okay, +关联这个。Okay， 1312 01:08:42,752 --> 01:08:46,354 so now all three buttons are sending that same show image. +现在三个按钮都和同一个 showimage 关联了。 1313 01:08:46,356 --> 01:08:49,057 So now we can actually demonstrate this. So let's +这次演示应该没问题。点击 1314 01:08:49,059 --> 01:08:53,094 do Cassini. Here it is showing this and once this appears, or +Cassini，会在这里展示，在展示出来后， 1315 01:08:53,096 --> 01:08:55,930 even before it appeared, I could hit Earth and +或者还没展示的时候，就可以点击 Earth， 1316 01:08:55,932 --> 01:08:59,000 -it just reusing this. No seugues, so there's no way I'm +it just reusing this. No seuges, so there's no way I'm +而且这是重用的。没有 segue，所以不会 1317 01:08:59,002 --> 01:09:02,837 creating a new MVC here. It's just reloading it, okay, +创建新的 MVC。只是在进行刷新， 1318 01:09:02,839 --> 01:09:07,842 just by setting the image URL on the image there. Got it? +只是重新设置了 image 的 URL。明白？ 1319 01:09:08,178 --> 01:09:11,813 Okay. Now, what about back on iPhone, though? +那在 iPhone 上会怎样呢？ 1320 01:09:11,815 --> 01:09:13,815 Let's go back to iPhone. +让我们回到 iphone。 1321 01:09:13,817 --> 01:09:18,286 Is this going to work over here? No, it's not +依然会有效吗？不，不行， 1322 01:09:18,288 --> 01:09:21,422 because it only does that thing if it's in split view. +因为这只能在 split view 的情况下可以。 1323 01:09:21,424 --> 01:09:24,759 Remember I said if split view controller, so if I hit Earth, +我记得我说过要 split view controller，所以这里点击 Earth， 1324 01:09:24,761 --> 01:09:28,163 it's not working at all now, cuz it's not segueing here. So +没有任何响应，因为根本没有 segue。 1325 01:09:28,165 --> 01:09:31,699 really what I need to do back here in Cassini is I need to +所以，回到 Cassini 项目，需要加上 1326 01:09:31,701 --> 01:09:35,904 say [COUGH] if I'm in a split view controller, then do this. +[咳嗽]，如果是 split view controller，处理这个。 1327 01:09:35,906 --> 01:09:39,107 Otherwise, I basically want to segue. Okay, so +否则，应该处理 segue 逻辑。 1328 01:09:39,109 --> 01:09:44,078 now I'm gonna show you how to segue from code. Okay, +所以我会演示如何用代码实现 segue。 1329 01:09:44,080 --> 01:09:46,147 you've only learned how to segue from, +因为之前只讲过从， 1330 01:09:46,149 --> 01:09:46,981 by dragging in Storyboard. +从 storyboard 中拖拽。 1331 01:09:46,983 --> 01:09:50,018 And now I'm gonna show you how to do it in code, +现在我会将如何使用代码， 1332 01:09:50,020 --> 01:09:53,788 which is you just say performSegueWithIdentifier. +只需要调用 performSegueWithIdentifier。 1333 01:09:53,790 --> 01:09:55,490 And you give it the identifier. So +给一个 identifier。 1334 01:09:55,492 --> 01:10:00,094 we'll use the Storyboard ShowImageSegue, +可以使用 StoryBoard.ShowImageSegue， 1335 01:10:00,096 --> 01:10:01,930 and the sender can be whatever you want, +sender 这个可以随便填， 1336 01:10:01,932 --> 01:10:05,200 I'm gonna have the sender be this sender button right here, +这里我希望 sender 就是按钮事件的 sender， 1337 01:10:05,202 --> 01:10:06,868 this button that's asking us to show image, so +就是这样按钮触发的 showimage， 1338 01:10:06,870 --> 01:10:09,137 it's gonna be one of those Earth things or whatever. +可能是 Earth，也可能是别的。 1339 01:10:09,139 --> 01:10:11,839 Now this, perform segue with identifier, +performSegueWithIdentifier 方法， 1340 01:10:11,841 --> 01:10:16,477 requires that such a segue exist in the storyboard. Okay, +要求传入的 segue 必须在 storyboard 中存在。 1341 01:10:16,479 --> 01:10:17,545 and we got rid of all those segues. +但我们之前删掉了所有 segue。 1342 01:10:17,547 --> 01:10:20,915 So that's not gonna work. We need to have a storyboard with +所以代码不会生效。我们需要 storyboard 中， 1343 01:10:20,917 --> 01:10:24,252 this identifier, and the way you do this is, you actually +有这些 identifier，实现方式是， 1344 01:10:24,254 --> 01:10:27,622 segue from the view controller itself. Instead of seguing +从 view controller 自己发起 segue，而不是 1345 01:10:27,624 --> 01:10:30,792 from one of the buttons, when you wanna segue in code, +从 button 发起 segue。如果需要用代码实现 segue， 1346 01:10:30,794 --> 01:10:32,527 you segue from the view controller itself, +那就需要 view controller 发起， 1347 01:10:32,529 --> 01:10:35,930 from this little icon right here down to wherever you want +从这个小图标拖到需要创建的 1348 01:10:35,932 --> 01:10:39,234 to segue to. So we want to segue to this, right here, +segue 上。我们需要 segue 这个， 1349 01:10:39,236 --> 01:10:42,537 put these close to each other. Okay, so I'm just gonna Ctrl + +把它们放到一起。Okay，按住 Ctrl 1350 01:10:42,539 --> 01:10:47,242 drag from here to here. It's gonna be, it can be show, +拖到，从这里到这里。选择 show， 1351 01:10:47,244 --> 01:10:50,178 because we're never doing this in a split view controller cuz +因为这个不会对 split view controller 中处理， 1352 01:10:50,180 --> 01:10:52,313 split view controller we're doing the other thing. So +split view controller 会有其他的处理逻辑。所以， 1353 01:10:52,315 --> 01:10:55,750 we do show. We've got this thing here now, this one +这里选择 show。这就完成了，这就是一个 1354 01:10:55,752 --> 01:10:59,387 segue, this segue sets up the whole view controller to here. +segue，这个 segue 包含了整个 view controller。 1355 01:10:59,389 --> 01:11:03,992 We still need to set its identifier to ShowImage. Okay? +我们还需要将 identifier 设为 ShowImage。Okay？ 1356 01:11:03,994 --> 01:11:07,996 And now, back here in this code, when we do perform segue +现在，回到代码中，当 preform segue 1357 01:11:07,998 --> 01:11:11,399 with identifier, it's going to do that segue. And +with identifier 时，就会处理 segue。 1358 01:11:11,401 --> 01:11:13,368 we're seguing from the view controller to the other one, +segue 就会从一个 view controller 跳转另一个， 1359 01:11:13,370 --> 01:11:15,470 not with the buttons anymore, from the view controller, so +而不是从按钮，是从 view controller， 1360 01:11:15,472 --> 01:11:22,977 let's see if that works now on iPhone All right, Cassini. +来看看 Cassini 在 iPhone 上能成功吗。 1361 01:11:22,979 --> 01:11:24,279 Sure enough it's working. Okay, so +当然没问题。Okay， 1362 01:11:24,281 --> 01:11:26,481 it's doing that segue, it's back to doing the segues. +能跳转过去，也能回来。 1363 01:11:26,483 --> 01:11:29,417 So this is a new MVC. Go back. This is a new MVC. +这是一个新的 MVC，返回，这又是一个新的 MVC。 1364 01:11:29,419 --> 01:11:33,054 But it's only doing it on iPhone because if you look at +但这只在 iPhone 上是这样，如果在代码的 1365 01:11:33,056 --> 01:11:35,089 our code over here in the showImage, +showImage 方法中， 1366 01:11:35,091 --> 01:11:38,159 if it's in a split view controller, it just reuses +我们判断了如果是 split view controller，而且 1367 01:11:38,161 --> 01:11:41,863 the image view controller that's already in the split, +image view controller 是 split 的 detail 时， 1368 01:11:41,865 --> 01:11:46,234 in the detail. Okay? Got all that? All right, +才进行重用。明白吗？好的。 1369 01:11:46,236 --> 01:11:48,670 I think I have time to do the last bit of slides here, +应该还有时间讲最后一部分讲义， 1370 01:11:48,672 --> 01:11:54,242 oops, which is on text field, go through it pretty quickly. +oops，是关于 text field 的，很快过一遍。 1371 01:11:54,911 --> 01:11:56,878 All right, so UITextField. I haven't been able to show +好的，UITextField。我现在还没办法展示， 1372 01:11:56,880 --> 01:11:59,714 it to you right now because it requires delegation to work. +因为它需要 delegation。 1373 01:11:59,716 --> 01:12:01,683 Without delegation, text fields don't work. So +没有 delegation，text field 就没反应。 1374 01:12:01,685 --> 01:12:04,585 UITextField is like UILabel but it's editable. +UITextField 和 UILabel 差不多，但它可编辑。 1375 01:12:04,587 --> 01:12:08,089 Users can touch on it and then a keyboard comes up and +用户点击它，键盘就会弹出， 1376 01:12:08,091 --> 01:12:09,424 they can start typing in it. +然后可以进行输入。 1377 01:12:09,426 --> 01:12:11,926 UITextField is not really a very main stream +UITextField 的输入方式 1378 01:12:11,928 --> 01:12:15,530 input mechanism on the iPhone because the keyboard is very +在 iPhone 上并不主流，因为键盘实在 1379 01:12:15,532 --> 01:12:18,700 small, okay? So, you only want to use UITextField when you +太小了，所以除非必要要用户 1380 01:12:18,702 --> 01:12:21,836 absolutely can't get the text from the user in any other +用键盘，否则不要使用这种方式。 1381 01:12:21,838 --> 01:12:23,705 way. You can't offer them a choice +别让他们从清单 1382 01:12:23,707 --> 01:12:26,708 from a list of the things, they have to actually type it +中选择，这也是需要输入的。 1383 01:12:26,710 --> 01:12:29,477 in, okay? So, be careful, this is not a desktop app that you +所以，要时刻谨记，你开发的不是桌面应用， 1384 01:12:29,479 --> 01:12:33,214 are building. It's a mobile app. All right so, +而是手机应用。所以说， 1385 01:12:33,216 --> 01:12:35,416 TextField is not a primary input source. Now, +textfield 不是主要的输入源。 1386 01:12:35,418 --> 01:12:39,354 the keyboard appears whenever a TextField becomes +如果 textfild 是第一响应者， 1387 01:12:39,356 --> 01:12:41,989 the first responder, and you can make a TextField the first +键盘就会弹出，要让 textfield 成为第一响应者，可调用 1388 01:12:41,991 --> 01:12:44,792 responder by sending it the message, becomeFirstResponder. +becomeFirstResponder 方法。 1389 01:12:44,794 --> 01:12:46,761 And then it will become the first responder. +然后它就成为第一响应者了。 1390 01:12:46,763 --> 01:12:48,529 You can make it stop being the first responder, +可通过调用 resignFirstResponder， 1391 01:12:48,531 --> 01:12:51,299 in which case the keyboard will go away, by saying, +来取消是第一响应者，如此， 1392 01:12:51,301 --> 01:12:54,202 resignFirstResponder, okay? +键盘就会消失，okay？ 1393 01:12:54,204 --> 01:12:54,669 So, the keyboard appears and +所以，键盘的弹出与 1394 01:12:54,671 --> 01:12:57,905 disappears purely if there's something on the screen +消失，是有屏幕上是否有第一响应者 1395 01:12:57,907 --> 01:13:00,641 that wants to be the first responder. Okay, simple as +而决定的。就这样简单。 1396 01:13:00,643 --> 01:13:06,981 that. Now, delegation is used here primarily with the return +delegation 在这里可以用于处理返回按钮的事件。 1397 01:13:06,983 --> 01:13:09,951 key. So, if you bring up that little software keyboard +如果你打开键盘，在它角落里的 1398 01:13:09,953 --> 01:13:11,919 in the corner, there's a button called Return. +那个按钮，就叫做返回按钮。 1399 01:13:11,921 --> 01:13:15,256 And if you click return the TextField's delegate will +如果点击返回按钮，textfield 的 delegate 方法 1400 01:13:15,258 --> 01:13:17,892 be sent this message textFieldShouldReturn. It's +textFieldShouldReturn 就会被调用。之所以 1401 01:13:17,894 --> 01:13:20,762 called ShouldReturn because it returns a Bool about whether +叫做 ShouldReturn，是因为需要返回一个 bool 值， 1402 01:13:20,764 --> 01:13:23,631 it should do target/action when that return happens. +用于告知是否应该响应按钮的 target/action。 1403 01:13:23,633 --> 01:13:26,534 Because a TextField is like a button, if someone types in +因为 textfield 就像是按钮，如果有键入值， 1404 01:13:26,536 --> 01:13:29,904 there and hits Return, it'll do target/action, okay? +并且点击了返回，就会触发 target/action。 1405 01:13:29,906 --> 01:13:30,405 You can control drag and +你可以通过按住 control 并拖拽 1406 01:13:30,407 --> 01:13:32,407 it'll target/action just like a button. But +来创建 target/action，这和 button 差不多。 1407 01:13:32,409 --> 01:13:35,476 this text field should return, either has to return true or +对于 textfield 的 should return 来说，返回 true， 1408 01:13:35,478 --> 01:13:37,278 it has to not be implemented by the delegate for +或者不实现这个代理方法， 1409 01:13:37,280 --> 01:13:41,182 that to work. But one thing, so usually do implement this, +都是一样的效果。不过通常这个方法都是实现了的， 1410 01:13:41,184 --> 01:13:43,818 because one thing you wanna do in here is resign first +因为需要在这个方法中，取消第一响应者。 1411 01:13:43,820 --> 01:13:47,155 responder. A lot of times when the user hits return, +绝大多数时候，在用户点击返回时， 1412 01:13:47,157 --> 01:13:48,656 you do the target/action, but +都会相应 target/action， 1413 01:13:48,658 --> 01:13:51,259 you want the keyboard to go away. So, a lot of times +需要隐藏键盘。所以，一般情况下， 1414 01:13:51,261 --> 01:13:52,660 you'll do that here and TextField should return. So, +都会在 should return 里面处理。 1415 01:13:52,662 --> 01:13:55,663 you just need to set yourself as the UITextField delegate, +只需要将自己设置 UITextField 的代理， 1416 01:13:55,665 --> 01:13:58,466 you've got to save it to the UITextField delegate, and +声明自己是 UITextField 的协议，并且 1417 01:13:58,468 --> 01:14:01,369 then you implement this method and inside just say sender, +实现该方法，然后方法中的 sender 1418 01:14:01,371 --> 01:14:03,805 which is the text field that's sending this to you, +就是 text field， 1419 01:14:03,807 --> 01:14:08,342 -design first responder. You can also find out when editing +resign first responder. You can also find out when editing +resign first responder。除此之外，也有其他地方需要 1420 01:14:08,344 --> 01:14:11,446 has ended in your TextField, meaning that the user +结束编辑，比如用户在 1421 01:14:11,448 --> 01:14:14,682 clicked on another TextField usually and you've resigned +点击另外一个 textfield 时，通常也需要取消当前的 1422 01:14:14,684 --> 01:14:17,285 first responder. Okay, any time you resign first +第一响应者。在取消第一响应者时， 1423 01:14:17,287 --> 01:14:19,787 responder you'll get sent this and you can ask the TextField, +就会调用这个方法，可以在方法中获取 textfield 1424 01:14:19,789 --> 01:14:23,758 ok, what text is in you. Okay, so that's another interesting +的 text 是什么。这也是有趣的方法。 1425 01:14:23,760 --> 01:14:26,360 one. And as I said, TextField's UIControl, +正如我所说，textfield 是 UIControl， 1426 01:14:26,362 --> 01:14:28,529 you can do target/action, just control, drag. +你可以添加 target/action，只需要 control 并拖拽。 1427 01:14:28,531 --> 01:14:32,600 The keyboard, you configure the keyboard actually by +对于键盘来说，其实配置键盘是和 1428 01:14:32,602 --> 01:14:33,401 talking to the TextField. +textfield 打交道的。 1429 01:14:33,403 --> 01:14:37,905 There's no UI keyboard object that you talk to in iOS, okay? +iOS 中并没有 UIKeyboard 这样的对象，okay？ 1430 01:14:37,907 --> 01:14:39,407 When you wanna configure your keyboard, +要配置键盘时， 1431 01:14:39,409 --> 01:14:42,343 you talk to the thing that's bringing the keyboard up. +就是在和唤起键盘的那个对象打交道。 1432 01:14:42,345 --> 01:14:43,411 In this case, the TextField. And +比如，textfield。 1433 01:14:43,413 --> 01:14:45,913 there's all kinds of methods in here you could look at. +大家可以看到，这里有一堆方法。 1434 01:14:45,915 --> 01:14:48,950 This is the UITextInputTraits protocol, so +这些都定义在 UITextInputTraits 协议中， 1435 01:14:48,952 --> 01:14:51,085 that's where you wanna look in the documentation, for +如果要在文档中查看，就要查 1436 01:14:51,087 --> 01:14:51,519 this protocol. Remember, +这个协议。记住， 1437 01:14:51,521 --> 01:14:54,088 a protocol is just a bunch of methods and bars, that's all +协议就是一堆方法的定义， 1438 01:14:54,090 --> 01:14:57,825 these are. And these will set what kind of keyboard it is, +这就是协议。而这些就决定了键盘的属性， 1439 01:14:57,827 --> 01:15:00,895 you're entering a URL? Is it a password thing, +如果在输入 URL？如果在输入密码， 1440 01:15:00,897 --> 01:15:04,999 where you can't see the text? All that stuff Is part of that +那就是不可见的文本。这些都是这个协议的 1441 01:15:05,001 --> 01:15:07,702 protocol, so you wanna look that up. One thing about +一部分，所以你应该好好看看。关于键盘， 1442 01:15:07,704 --> 01:15:11,806 the keyboard, it comes up over your UI so it might block. +还有一个问题，它弹起是，可能会挡住界面。 1443 01:15:11,808 --> 01:15:14,141 It might even block the TextField that you're +如果没小心处理，也有可能正在输入时， 1444 01:15:14,143 --> 01:15:16,744 editing in, if you're not careful about how you layer UI +界面就被挡住了。 1445 01:15:16,746 --> 01:15:19,680 out. And we are gonna talk later into the quarter about +这个会在之后的 1446 01:15:19,682 --> 01:15:23,017 this NSNotification center. It's a way to get notified +NSNotificationCenter 中谈到。这是得知这类事件的渠道。 1447 01:15:23,019 --> 01:15:25,920 when things happened and when a keyboard comes up and +当键盘弹起，可能挡住界面时， 1448 01:15:25,922 --> 01:15:28,789 blocks your UI, you will get notified, okay? +可以收到通知， 1449 01:15:28,791 --> 01:15:29,423 And when we talk about this, +在我们具体介绍的时候， 1450 01:15:29,425 --> 01:15:32,593 you'll understand what you can do. You could move your UI +你就知道该怎么做了。你可以把界面 1451 01:15:32,595 --> 01:15:35,129 up from out underneath it, or maybe it's in scroll view, +移上去，如果是 scroll view， 1452 01:15:35,131 --> 01:15:37,265 you could scroll up or something like that, but +可以滚上去之类的， 1453 01:15:37,267 --> 01:15:38,966 you have to be careful about this. They keyboard, +但处理的时候要小心。键盘真的是 1454 01:15:38,968 --> 01:15:40,835 just boom, comes up right on top of your UI and +一下子就弹起来了，盖在界面上， 1455 01:15:40,837 --> 01:15:42,803 it can really block things, okay? So, +还挡住界面。 1456 01:15:42,805 --> 01:15:45,940 you'll need to eventually learn how to respond to this +所以你必须要学会如何接收这个 1457 01:15:45,942 --> 01:15:49,443 notification. There's lots of other TextField properties +通知。这些是 textfield 的另外一些属性， 1458 01:15:49,445 --> 01:15:53,447 that are interesting here. You can actually put a little +也挺有趣的。这个可以给它 1459 01:15:53,449 --> 01:15:55,683 button on the side. You can decide where, +在边上加上小按钮，位置由你定， 1460 01:15:55,685 --> 01:15:58,920 when the user touches it, does it clear out what's in there? +当用户点击这个按钮时，可以清空输入。 1461 01:15:58,922 --> 01:16:00,855 You can have a place holder in there, so +你也可以加 place holder， 1462 01:16:00,857 --> 01:16:02,189 that when there's nothing in the field, +在 textfield 上什么都没有时， 1463 01:16:02,191 --> 01:16:03,457 there's a kind of a light gray text. +可以展示一行浅灰色的文本。 1464 01:16:03,459 --> 01:16:05,626 Kind of telling the user what's supposed to be there, +比如告诉用户这文本框支持什么， 1465 01:16:05,628 --> 01:16:06,994 that kind of thing. +之类的。 1466 01:16:06,996 --> 01:16:09,430 Anytime I show you anything in this class, +每次我给大家展示类的信息是， 1467 01:16:09,432 --> 01:16:12,066 like UITextField or UIButton or anything, of course I'm +比如 UITextField，UIButton 这类，都是 1468 01:16:12,068 --> 01:16:15,069 expecting you to go read the documentation, okay. Otherwise +希望大家能去查阅文档。否则， 1469 01:16:15,071 --> 01:16:17,271 you're just not gonna know how to use these things. +你无法知道这些该怎么使用。 1470 01:16:17,273 --> 01:16:18,306 I only have a minute or +课堂上，我只有 1471 01:16:18,308 --> 01:16:20,007 two in these classes, in the lectures to +几分钟时间，只够 1472 01:16:20,009 --> 01:16:22,610 kind of tell you these exist. If you need to be able to go, +告诉大家里面有什么。如果要弄清楚， 1473 01:16:22,612 --> 01:16:24,345 use the documentation to figure them out, okay? +还是需要从文档中学习。 1474 01:16:24,347 --> 01:16:27,148 And this is a classic example figuring out how to +这是学习 textfield 最好的 1475 01:16:27,150 --> 01:16:30,184 use TextField here, Okay? Yeah, they have these left and +方式了。这里的 left 和 1476 01:16:30,186 --> 01:16:33,120 right overlays are kind of fun. You control the layout +right 覆盖视图也挺有趣，你可以通过布局 1477 01:16:33,122 --> 01:16:35,890 all this all kinds of stuff. The keyboard has +来控制它们。键盘有 1478 01:16:35,892 --> 01:16:39,093 an interesting bar in it which is sorry the input +一个 bar，哦不，一个输入协议， 1479 01:16:39,095 --> 01:16:42,263 trait protocol. Called input accessory view you can +名为 input accessory view，你可以将这个视图 1480 01:16:42,265 --> 01:16:44,131 actually put a little view on top of your keyboard. +放在键盘的顶部。 1481 01:16:44,133 --> 01:16:45,833 You've probably seen that in some apps. Right, +你可能在其他的 app 中看见过。对吧， 1482 01:16:45,835 --> 01:16:48,436 has kind of like a little view has custom stuff, +一个很小的，有些自定义控件的视图， 1483 01:16:48,438 --> 01:16:50,871 you can put your own view just by setting this bar. +你可以通过配置这个 bar 来创建自己的视图。 1484 01:16:50,873 --> 01:16:54,308 It's kinda fun. All right, so that's it. On Friday, +这倒是挺有趣的。好的，这就是全部内容。本周五， 1485 01:16:54,310 --> 01:16:56,377 we do have a section. It's on UI Testing, +我们还有一个小节，关于 UITesting， 1486 01:16:56,379 --> 01:17:00,147 which is literally being able to record the UI being +它可以详尽的记录 UI 交互， 1487 01:17:00,149 --> 01:17:02,049 interacted with and then writing code that tests, +还可以写代码进行测试， 1488 01:17:02,051 --> 01:17:03,484 to make sure it's doing what it's supposed to be doing. +以确保操作都是正确的。 1489 01:17:03,486 --> 01:17:06,921 -That's really cool. A feature in x code. And then next week, +That's really cool. A feature in xcode. And then next week, +这是 xcode 中非常棒的特性。下一周， 1490 01:17:06,923 --> 01:17:08,823 we're going to talk about Table View and +我们会讲解 tableview， 1491 01:17:08,825 --> 01:17:09,190 Core Data, okay? +还有 core data。 1492 01:17:09,192 --> 01:17:11,892 Table View is a way of showing big huge amounts of data. +table view 用于展示一系列数据， 1493 01:17:11,894 --> 01:17:15,563 And Core Data is a database to store big huge amounts of +而 core data 则是用于存储 1494 01:17:15,565 --> 01:17:17,164 data in. Assignment four. +一系列数据。关于作业， 1495 01:17:17,166 --> 01:17:18,399 Since it's a table view based assignment, +既然都是关于 table view 的作业， 1496 01:17:18,401 --> 01:17:21,869 we'll go out at the end of the next lecture, and it'll be due +所以也会在下一讲结束，也就是 1497 01:17:21,871 --> 01:17:24,772 a week later. And there are no more reading assignments. +一周以后。今天没有额外的阅读任务。 1498 01:17:24,774 --> 01:17:27,408 I can tell some of you haven't done your reading assignment +我知道一部分同学没有完成阅读任务， 1499 01:17:27,410 --> 01:17:29,777 because you don't know some of the questions I'm asking. +因为今天我提的好几个问题都没回答上来。 1500 01:17:29,779 --> 01:17:30,778 Go back and read that stuff, really. +记得之后要去看，真的， 1501 01:17:30,780 --> 01:17:34,348 it's not that much stuff, you should really understand all +这又没多少东西，而且这些知识你必须要知道， 1502 01:17:34,350 --> 01:17:36,350 these things, like the where clause, +比如闭包， 1503 01:17:36,352 --> 01:17:37,718 or you're going to be writing weird code. +否则写出的代码就很奇怪。 1504 01:17:37,720 --> 01:17:40,154 Because people say, why didn't they just use where there, +因为大家会说，你为什么不用这个， 1505 01:17:40,156 --> 01:17:40,588 why did they put another if?. +为什么这里要加上判断。 1506 01:17:40,590 --> 01:17:44,525 -Okay? So, you don't want to be that guy, okay? Al lright, +Okay? So, you don't want to be that guy, okay? Allright, +Okay？你不会想被这样对待的，好吗？ 1507 01:17:44,527 --> 01:17:47,228 I'll see you guys next week. >> For +同学们，下周见。 1508 01:17:47,230 --> 01:17:47,261 more, please visit us at Stanford.edu +更多信息，请访问 Stanford.edu From 4e288f0bdac0e9d69fdd108300bb1ae9e053f16a Mon Sep 17 00:00:00 2001 From: ZhangNan_ludan Date: Tue, 18 Apr 2017 19:05:23 +0800 Subject: [PATCH 23/23] =?UTF-8?q?=E7=BF=BB=E8=AF=91=E4=BA=86=E7=AC=AC6?= =?UTF-8?q?=E9=9B=86=20500-1000=20(#59)?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 第6集 500-1000 --- ... FaceIt, and View Controller Lifecycle.srt | 522 +++++++++++++++++- 1 file changed, 504 insertions(+), 18 deletions(-) diff --git a/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt b/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt index fec5bc5..def7ae4 100755 --- a/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt +++ b/subtitles/6. Multiple MVCs, Segues, FaceIt, and View Controller Lifecycle.srt @@ -1997,1186 +1997,1472 @@ Okay? All right, so let's talk about split view controller. 500 00:25:30,029 --> 00:25:33,230 We haven't even done anything with iPad at all in this class +目前为止，这门课还没有任何涉及 iPad 应用的内容 501 00:25:33,232 --> 00:25:36,200 yet. So this is our first time doing it and we're gonna put +所以现在是我们第一次讨论关于 502 00:25:36,202 --> 00:25:40,004 this in split view controller where this is the master and +有 master controller 和 detail controller 的 503 00:25:40,006 --> 00:25:41,839 this is the detail, makes sense, right? - +split view controller 明白了没？ 504 00:25:41,841 --> 00:25:42,706 Because we're clicking in the master, +我们点这个展示 master controller 505 00:25:42,708 --> 00:25:46,110 this will be the detail that's shown from clicking on this. +点这个展示 detail controller 506 00:25:46,112 --> 00:25:47,545 So how do we do a split view controller? +我们怎么处理一个 split view controller 呢？ 507 00:25:47,547 --> 00:25:50,514 Same way as tab bar. I'm gonna go down here, right below tab +给 tab bar 的一样，我在这里 508 00:25:50,516 --> 00:25:53,884 bar is split view controller. I'm gonna drag that out, +Tab Bar Controller 下面就是这个 Split View Controller 509 00:25:53,886 --> 00:25:56,987 I get a whole bunch of junk with it. We'll zoom out so +把这个拖出来，我就得到了一大堆垃圾(controller) 510 00:25:56,989 --> 00:26:00,858 you can see it. Okay. See, I got all these extra things, so +缩小了你就看见了，我得到了好多额外的东西 511 00:26:00,860 --> 00:26:02,526 I'm gonna, click on these extra things and +所以我要把这些额外的统统删掉 512 00:26:02,528 --> 00:26:05,896 delete them, don't want any of them. Okay. So I just have +一个都不想留，所以我现在只有 513 00:26:05,898 --> 00:26:08,832 the split view controller and my two guys here. +这个 split view controller 和 刚刚那两个 controller 514 00:26:08,834 --> 00:26:11,402 Of course I want the split view controller, again, +我想让这个 split view controller 变为最早展示出来 515 00:26:11,404 --> 00:26:14,471 to be the start so I'm going to put the arrow there. And +所以我把箭头放在这里 516 00:26:14,473 --> 00:26:18,676 then, in order to hook up master and detail, Ctrl+Drag. +然后，为了将 master、detail 与 split view controller 联系起来 517 00:26:18,678 --> 00:26:24,181 Master, Ctrl+Drag, detail. Okay, +Ctrl+Drag 选择 Master，Ctrl+Drag 选择 detail 518 00:26:24,183 --> 00:26:26,917 so that's how we set it up, couldn't be simpler. So let's +我们就是这么建立起他们的关系，再简单不过了 519 00:26:26,919 --> 00:26:30,854 run, but let's run on iPad, so I'm gonna, on iPad 2 here, +现在在 iPad 上运行，我用 iPad 2 模拟器 520 00:26:30,856 --> 00:26:34,425 we'll run and hopefully this will show up as a master and +运行起来，希望这个会作为 master 521 00:26:34,427 --> 00:26:42,566 this will be the detail. All right. So here's the iPad. +这个会作为 detail 展示出来，这是 iPad 522 00:26:42,568 --> 00:26:45,469 Here's the detail. You notice that when it's in portrait +这是 detail controller，你可能注意到当在竖屏状态下 523 00:26:45,471 --> 00:26:46,604 it fills the screen with the detail, +detail controller 充满了屏幕 524 00:26:46,606 --> 00:26:50,608 and you get the master by dragging out from the side. +通过拖动侧边，master controller 就展示出来了 525 00:26:50,610 --> 00:26:53,744 See that? Okay? That's how you get the master. And +看到了吗？竖屏就通过这种方式看到 master controller 526 00:26:53,746 --> 00:26:54,778 if you're in landscape, +如果横过来，变成横屏状态 527 00:26:54,780 --> 00:26:58,782 then they're both onscreen at the same time. Now, if I click +master 和 detail 就在屏幕上同时展示出来 528 00:26:58,784 --> 00:27:02,753 on these, I want this face to show me angry, show me happy, +如果我点 Angry，我希望这个脸变成生气的样子 529 00:27:02,755 --> 00:27:04,455 show me worried, show me mischievous, okay? +变成高兴、变成担忧、变成淘气的样子 530 00:27:04,457 --> 00:27:07,224 So how do I do that? This is where the segues come in. +这怎么做呢？这时我们就需要用到 segue 了 531 00:27:07,226 --> 00:27:10,561 Okay? This is where we have to have this view controller +我们需要让这个 view controller 转场 532 00:27:10,563 --> 00:27:12,396 segue to create a new one of these and +然后 create 一个detail controller 533 00:27:12,398 --> 00:27:15,132 when it creates this, it's going to create it with +当 create 时，会 create 一个有确切表情值的 controller 534 00:27:15,134 --> 00:27:18,769 the proper facial expression, okay? So it's going to prepare +所以，它会准备好表情值 535 00:27:18,771 --> 00:27:22,172 it with a facial expression and show it. Okay? So - +然后将这个确切的表情展示出来 536 00:27:22,174 --> 00:27:26,276 let's do those segues. The way we do segues, also Ctrl+Drag. +我们来设置这些转场，同样是 Ctrl Drag 设置 537 00:27:26,278 --> 00:27:29,847 So, let me zoom in here so you can see this. All right? +我放大点你就可以看到了 538 00:27:29,849 --> 00:27:32,783 I'm gonna Ctrl+Drag from whichever of these buttons +我按住 segue 开始的 button，然后 Ctrl + Drag 539 00:27:32,785 --> 00:27:35,352 I want to segue from. I'm gonna segue from all four, so +我想从这4个button开始连 segue 540 00:27:35,354 --> 00:27:38,222 I'm gonna have four segues. So like angry here I'm +所以我应该有4个segue，像从这里按住 angry button 541 00:27:38,224 --> 00:27:42,493 just gonna Ctrl+Drag down to this MVC. And let go. +然后 Ctrl + Drag 到这个 MVC，然后松手 542 00:27:42,495 --> 00:27:44,728 And it says, well what kind of segue do you want? +这里会让你选择你想要的 segue 类型 543 00:27:44,730 --> 00:27:45,896 Show, show detail, modally or +Show, show detail, modally 或者是 544 00:27:45,898 --> 00:27:49,133 pop over. Well, we're in the split view controller here so +pop over。因为我们用的是 split 控制器，所以 545 00:27:49,135 --> 00:27:52,002 I want to show detail, right? Split view. Master detail. +我选择 show detail 546 00:27:52,004 --> 00:27:55,406 Show detail. Bam. There it is right there. Okay? +这个是split view，然后 master detail 用 show detail 连接，对吧？ 547 00:27:55,408 --> 00:27:58,409 Created this little thing here. That's my segue. And +做了这些工作，这就是我的 segue 548 00:27:58,411 --> 00:28:01,578 this segue can be inspected. You can see it up here, okay? +这些 segue 是可以被检查的，你可以在这里看到他们 549 00:28:01,580 --> 00:28:04,214 This is the attributes inspector. And it's got +这是属性检查器，会显示 show detail 的类型 550 00:28:04,216 --> 00:28:07,184 the kind of show detail, also known as a replace segue. +也常常被叫做 replace segue 551 00:28:07,186 --> 00:28:11,055 It animates, it shows that this segue is going to happen +这是 Animates，这个说明这个 segue 可以用动画的形式展现 552 00:28:11,057 --> 00:28:13,991 in an animated fashion, so it's going to slide in or +是滑进或者别的方式 553 00:28:13,993 --> 00:28:16,427 whatever. It's not always makes sense to animate but +并不总是可以选择 Animates 的，有时候可以 554 00:28:16,429 --> 00:28:19,963 sometimes it does. Class and module, don't worry about +有时候不行，不用担心这些，比如 Class 和 Module 555 00:28:19,965 --> 00:28:21,665 that. That's for creating your own custom segues, +这些帮助你设置你自定义的 segue 556 00:28:21,667 --> 00:28:23,233 which we're not going to talk about in this class. +这些内容有一些超前，所以我们这节课不会讨论到 557 00:28:23,235 --> 00:28:26,303 A little bit too advanced. And then, here is the all +最重要的属性是 identifier 558 00:28:26,305 --> 00:28:29,440 important identifier. So here, we have to give any string +我们需要用字符串来唯一确定这个segue 559 00:28:29,442 --> 00:28:34,011 we want that identifies this segue. So I could call this, +比如，我可以叫这个segue 560 00:28:34,013 --> 00:28:38,682 for example, the angry segue, maybe I'd want a verb +为 angry segue 561 00:28:38,684 --> 00:28:41,885 phrase like show anger or something like that but +我应该用一个动词，比如 show anger 或者 562 00:28:41,887 --> 00:28:45,022 it's fine also maybe to have a nice simple word like anger. +就是一个单一的明确的名词，像 anger 563 00:28:45,024 --> 00:28:46,757 So that's my angry segue right there. +所以，这是我的 angry segue 564 00:28:46,759 --> 00:28:50,461 Okay. And so now let's wire up the other ones, Ctrl+Drag this +好，现在我们连一下剩余的控件 565 00:28:50,463 --> 00:28:54,331 one down here. This one is also going to be show detail. - +在这里按 Ctrl + Drag，这个是 show detail + 566 00:28:54,333 --> 00:28:58,569 They're all going to be show detail. I'll do worried also. +我想这个也应该是 show detail 567 00:28:58,571 --> 00:29:03,340 Show detail, oops, not present modally, get rid of that. - +oops，不是 present modally，删掉这个 568 00:29:03,342 --> 00:29:08,278 Alright. Then here. Show detail. +这个也是 Show detail 569 00:29:08,280 --> 00:29:12,716 Mischievous. Show detail. +给淘气的也连上Show detail segue 570 00:29:12,718 --> 00:29:15,886 Okay, now I need to set the identifier for all of these. +现在，我需要给这些 segue 都设置 identifier 作为唯一标示 571 00:29:15,888 --> 00:29:19,223 What's really cool is if I click on one it'll tell me who +特别酷的是，如果我点击一个 segue，他会显示 572 00:29:19,225 --> 00:29:23,227 the sender of this segue is. So there's worried, okay. +这个 segue 的发送者是哪一个，这个是 worried 573 00:29:23,229 --> 00:29:27,030 Worried. Here is happy, and +这个是 happy 574 00:29:27,032 --> 00:29:30,200 we'll call this my happy segue. +我想把这个叫 happy segue 575 00:29:30,202 --> 00:29:34,238 This one, angry already set up. This one, mischievous, +这个，angry 已经设置好了 576 00:29:34,240 --> 00:29:38,876 okay. Mischievous. Hopefully I spelled that right. Okay, so +这个是 Mischievous，希望我正确地拼写了这几个词 577 00:29:38,878 --> 00:29:41,378 now we've got these segues set up so let's run and +现在我设置了这几个 segue，然后运行一下 578 00:29:41,380 --> 00:29:48,218 see what happens here. All right, angry, happy, +看看会发生什么 579 00:29:48,220 --> 00:29:51,855 still nothing's happening. What is the problem here? +什么也没发生，问题出在什么地方呢？ 580 00:29:51,857 --> 00:29:54,158 Okay, well, it is actually segueing here. +Okay，这确实是 segue 的问题 581 00:29:54,160 --> 00:29:56,527 It's replacing that face with a new MVC, but +程序用了新的 MVC 来替换这张脸 582 00:29:56,529 --> 00:29:59,663 that new face has not been prepared to show the emotion +但是，这个新 face 还没有准备好展示这个表情 583 00:29:59,665 --> 00:30:02,533 we want so it's just showing the default emotion, +所以它仅仅展示在 storyboard 中展现的 584 00:30:02,535 --> 00:30:05,569 whatever happened to be in our storyboard, right? +默认表情，对吗？ 585 00:30:05,571 --> 00:30:07,471 This face right here just happens to be, or or +这个 face 在这里是这么展示的 586 00:30:07,473 --> 00:30:10,374 it's actually what happens to be the default our model is is +或者会展示默认的 model 表现的表情 587 00:30:10,376 --> 00:30:14,611 that. Okay, so we need to, in all these segues, prepare +所以，我们需要给所有 segue 准备 588 00:30:14,613 --> 00:30:18,849 the MVC that we are segueing to. We do that in the source +其需要展示的 model，我们在 segue 的源头设置 589 00:30:18,851 --> 00:30:21,018 view controller, that is the emotions view controller. +在这里应该是 emotions 控制器 590 00:30:21,020 --> 00:30:23,287 This is the thing that implements Prepare for Segue. +实现 prepareForSegue 这个方法 591 00:30:23,289 --> 00:30:26,924 So I am just going to un comment out the comments here, +我要删掉这些注释 592 00:30:26,926 --> 00:30:31,595 okay, for my Prepare for Segue. Make lots of space. +为 prepareForSegue 挪一些空间 593 00:30:31,597 --> 00:30:33,363 Alright, so here we have Prepare for Segue, +在这里写上 prepareForSegue 594 00:30:33,365 --> 00:30:36,466 we get the two arguments, the segue which tells us a little +我们需要两个参数，segue 参数告诉我们 595 00:30:36,468 --> 00:30:37,401 bit about which segue it is and +这是哪个segue 596 00:30:37,403 --> 00:30:40,137 what the destination view controller is and then we have +它的目的 controller 是哪一个 597 00:30:40,139 --> 00:30:42,339 the sender. That's going to be those buttons, +还有一个 sender 参数，这应该是这些按钮 598 00:30:42,341 --> 00:30:44,675 like the angry button, the mischievous button. +像是 angry button、mischievous button 599 00:30:44,677 --> 00:30:45,509 That's what this is going to be, - +这些应该就是这些控件 600 00:30:45,511 --> 00:30:46,977 it's going to be the UI button. Okay? +像是 UIButton 601 00:30:46,979 --> 00:30:49,913 This is any object because it is allowed to be any object. +这里必须是一些对象 602 00:30:49,915 --> 00:30:50,747 In this case it's a button, but +在这种情况下，就是 button 603 00:30:50,749 --> 00:30:53,083 it's allowed to be any object. All right. +但是，也可以允许是其他对象 604 00:30:53,085 --> 00:30:54,618 So what do we do here in preparing for +我们在这里应该写些什么来为 segue 做准备呢？ 605 00:30:54,620 --> 00:30:57,354 segue? The first thing I'm going to do is get a hold +第一，我需要获取到 606 00:30:57,356 --> 00:30:59,089 of the destination view controller, and +segue 目标 controller 607 00:30:59,091 --> 00:31:01,692 make sure that it's a face view controller. +确保他是 face view controller 608 00:31:01,694 --> 00:31:04,695 Cuz if it's not, I don't really know how to, +如果他不是的话，我确实不知道应该 609 00:31:04,697 --> 00:31:04,761 the segue so I'm just going to do nothing in that case. So +怎么为这个 segue 做准备 610 00:31:04,763 --> 00:31:07,497 to prepare for +在这种条件下 611 00:31:07,499 --> 00:31:09,600 I'm going to create a little local variable, okay? +我需要创造一个局部变量 612 00:31:09,602 --> 00:31:13,537 I'm going to call it destinationvc, destination +叫做 destinationvc 613 00:31:13,539 --> 00:31:18,375 view controller. And that's just equal to the segue, +表示目的的 controller，这个等于 614 00:31:18,377 --> 00:31:21,979 destin, segue, destinationViewController, +segue 的 destinationViewController 615 00:31:21,981 --> 00:31:25,415 okay? Now this is a UIViewController, okay, +现在，这个就是一个 UIViewController 616 00:31:25,417 --> 00:31:30,087 of some sort, it's some sub-class of UIViewController. +但是，应该是 UIViewController 的子类 617 00:31:30,089 --> 00:31:32,556 I suppose it could even be UIViewController itself. +这应该就是 UIViewController 本身 618 00:31:32,558 --> 00:31:35,225 There's probably a subclass of it, and so I need to get +这里应该用一个他的子类，所以我需要获得其子类 619 00:31:35,227 --> 00:31:38,595 that subclass, I need to get this variable, in some way, +我需要让这个变量 620 00:31:38,597 --> 00:31:41,832 so that it's a subclass of it. Or I can't work with it. +变为其子类 621 00:31:41,834 --> 00:31:44,434 Right? Because, UIViewController, I wouldn't +要不然我不能将一些属于 faceViewController 的消息 622 00:31:44,436 --> 00:31:47,871 be able to send any of the face view controller messages +传给他 623 00:31:47,873 --> 00:31:51,642 to it, because it's just a generic UIViewController, so I +因为他只是一个通用的 UIViewController 624 00:31:51,644 --> 00:31:55,612 need to get myself a faceview controller so I'm gonna say, +所以我需要得到一个 faceViewController 625 00:31:55,614 --> 00:31:58,382 if I can let facevc, which is a new variable, +if let facevc 626 00:31:58,384 --> 00:32:01,785 equal the destinationvc As a FaceViewController. +等于之前的变量 destinationvc 作为 FaceViewController 627 00:32:01,787 --> 00:32:04,855 Then I'm ready to rock here. Okay, now I have +然后我准备在这里做操作 628 00:32:04,857 --> 00:32:07,324 a FaceViewController, okay? So I've just casted. +现在，我通过转型获得了一个 FaceViewController 629 00:32:07,326 --> 00:32:10,460 They're similar to how I can't work with any object, +这跟之前我不能做特殊操作的 630 00:32:10,462 --> 00:32:12,429 I really can't work with a generic UIViewController. +通用 UIViewController 类似 631 00:32:12,431 --> 00:32:15,265 I need the subclass. Otherwise how am I going to set its - +我获得了他的子类，然后， 632 00:32:15,267 --> 00:32:19,269 model, okay? I have to be able to talk to it. All right. So +接下来，我需要设置这个 controller 的 model 633 00:32:19,271 --> 00:32:22,472 now I have this destination view controller. +现在我有了代表目标的 controller 634 00:32:22,474 --> 00:32:25,676 Now I need the identifier. So here I'm gonna say, if I can +现在，我需要标识符 635 00:32:25,678 --> 00:32:30,180 let the identifier equal the segue's identifier. Okay, +我需要让标识符等于 segue 的标识符 636 00:32:30,182 --> 00:32:33,183 -so here I'm just checking to make sure it's not nill. +so here I'm just checking to make sure it's not nil. +这样写是为了检查确保它不为空 637 00:32:33,185 --> 00:32:35,953 Now it should be angry, or mischievous, or happy. +他可以是 angry 、mischievous 或者是 happy 638 00:32:35,955 --> 00:32:38,355 One of those identifiers that I put in the stored word, +可以是我之前设置的任何一个标识符，对吧？ 639 00:32:38,357 --> 00:32:40,824 right? And I could do something here like, +我应该写 640 00:32:40,826 --> 00:32:42,793 switch on the identifier. +switch 标识符 641 00:32:42,795 --> 00:32:46,964 And if it's angry then I'm going to have my face vc's +如果是 angry，我应该写让我的表情 controller 642 00:32:46,966 --> 00:32:50,634 expression be a facial expression that's angry, blah, +表现生气的表情 643 00:32:50,636 --> 00:32:51,668 blah, blah. I could do that but +blah，我可以这么写 644 00:32:51,670 --> 00:32:55,572 that's going to be allot of if then, blah, blah, okay, mess. +但是，会是一些很乱的代码 645 00:32:55,574 --> 00:32:58,308 So instead I'm going to do one of my favorite ways to +所以，相反的是，我会写一些我喜欢的 646 00:32:58,310 --> 00:33:01,878 program, as you're probably getting the, +编程风格的代码，你可能已经想到了 647 00:33:01,880 --> 00:33:05,048 idea about which is use a dictionary. Okay, so +对的，我们要用字典来表示 648 00:33:05,050 --> 00:33:08,752 I have this dictionary I'm gonna type in real fast, okay, +我快速的写一下这些代码 649 00:33:08,754 --> 00:33:12,556 and this dictionary has keys which are the identifiers, and +这些字典以这些标识符为键 650 00:33:12,558 --> 00:33:17,761 it has values which are the appropriate facial expression. +对应的值为合适的 facial expression 模型 651 00:33:21,100 --> 00:33:21,732 Okay, got that, so +明白了吗？ 652 00:33:21,734 --> 00:33:25,402 instead of doing all of this switching on the identifier +与在这里 switch 这些标识符相反的是 653 00:33:25,404 --> 00:33:29,206 thing, I'm just going to say if I can let the expression +让 expression 变量等于我想要的 654 00:33:29,208 --> 00:33:32,275 that I want equal these emotional faces up here. +facial expression 模型 655 00:33:32,277 --> 00:33:38,081 Tha's this dictionary up here. Index by the identifier. +通过标识符来索引字典中的值 656 00:33:38,884 --> 00:33:41,184 Okay? Then I know the expression that I want. +然后，我获得了对应的表情模型 657 00:33:41,186 --> 00:33:45,489 And now I can prepare my face VC okay, by setting its +我可以为我要展示的 face VC 做准备 658 00:33:45,491 --> 00:33:48,992 expression equal to this expression. Okay, and remember +让他的 expression 模型等于这个 expression 659 00:33:48,994 --> 00:33:54,197 FaceVC.expression, that is just FaceViewControllers model +你记得吗? 在 FaceViewControllers 里它的模型是一个 660 00:33:54,199 --> 00:33:57,534 which is a public bar. This View Controller allows +公共变量，它允许 661 00:33:57,536 --> 00:33:59,669 its model to be set externally, publicly, +在外部设置其模型 662 00:33:59,671 --> 00:34:04,041 okay, which makes sense given this kind of model. +这让我们可以在对应的地方设置其 model 663 00:34:04,043 --> 00:34:06,043 Not all, and doesn't make sense always for - +这样仅是在这个 viewcontroller 中 664 00:34:06,045 --> 00:34:08,912 every MBC to allow it's model to be set but often it makes +设置其 model ，并不是所有viewcontroller 都可以设置 665 00:34:08,914 --> 00:34:13,216 some sense. Alright, so now I've prepared this Faceview +现在我已经为这个 faceViewController 设置好了 666 00:34:13,218 --> 00:34:17,754 controller to do what it needs to do. Everybody got that? OK. +它需要的东西，大家都明白吗？ 667 00:34:17,756 --> 00:34:26,396 So now let's run it and see if it's working. Okay. +现在我们运行一下，来看看是否正确显示 668 00:34:26,398 --> 00:34:30,267 So here we go, we have our iPad here, let's try angry. +这是我们的模拟器 iPad，点击 angry 669 00:34:30,269 --> 00:34:35,338 Crash a roo. Hmm. Wonder why that crashed? Well let's look, +哦，崩溃了，想一想为什么会崩溃呢？我们来检查下 670 00:34:35,340 --> 00:34:37,941 let's use the debugger. Okay, we haven't used the debugger +我们需要用一下 debugger 模式，我们还没有 671 00:34:37,943 --> 00:34:41,044 much in these demos but let's do it here. Seems like, +在这个 demo 中用过这个方法 672 00:34:41,046 --> 00:34:43,280 okay, whenever I have a crash, I always look first in +不管什么时候，程序崩溃了，我总是先查看 673 00:34:43,282 --> 00:34:45,615 the console, okay, because the console is always going to +控制台输出的信息，因为控制台总会告诉我一些 674 00:34:45,617 --> 00:34:47,918 tell me something about what happened. And here it says +关于崩溃的信息，这里显示 675 00:34:47,920 --> 00:34:51,288 unexpectedly found nil while unwrapping an optional value. +在解包一个可选值时，意外地发现了空异常 676 00:34:51,290 --> 00:34:53,857 Okay, well this is probably the number one crasher you're +这种异常你可能经常获得 677 00:34:53,859 --> 00:34:56,927 ever going to get, it's one of the few ways actually to crash +在 Swift 代码中，你可能经常 678 00:34:56,929 --> 00:34:59,963 Swift code is to have unwrapping and nil. +在解包时，发现空异常 679 00:34:59,965 --> 00:35:03,366 So it is happening on this orange line of code. +所以，在这一行，发生了这个异常 680 00:35:03,368 --> 00:35:10,607 I am looking here. Does anyone see an optional here? No? +我看这一行，有人发现这里有可选值了吗？ 681 00:35:10,609 --> 00:35:13,110 Nobody sees an optional on this line of code? +没有人在这一行发现可选值吗？ 682 00:35:13,112 --> 00:35:15,846 It doesn't look like it, does it? Because you do not see any +这一行看上去没有可选值吗？ 683 00:35:15,848 --> 00:35:18,081 exclamation points. I am not unwrapping anything. +可能因为你没有看到感叹号，我没有解包任何值 684 00:35:18,083 --> 00:35:21,251 What is going on? Well actually what is face view, +发生了什么呢？其实是这个 faceVIew 685 00:35:21,253 --> 00:35:25,589 what's its type? Anyone remember? Our outlet, +它的类型有人记得吗？ 686 00:35:25,591 --> 00:35:31,094 that's our outlet remember here? Right, it's a optional +这是我们的 outlet，还记得吗？ 687 00:35:31,096 --> 00:35:36,900 face view, okay? It's implicitly unwrapped okay, +这是一个可选值得 faceView，他隐式解包了 688 00:35:36,902 --> 00:35:40,904 but it's still an optional. And I told you in the slides, +但是他确实是一个可选值，ppt 里我说过 689 00:35:40,906 --> 00:35:45,041 that your outlets are not set at the time you're preparing. +在你准备 segue 时，这些outlet还没有被设置 690 00:35:45,043 --> 00:35:49,179 So this face view right here, okay, is nil, let's look. +所以，这里的 faceView 为空 691 00:35:49,181 --> 00:35:52,215 Okay, here's where our variables are down here, +我们在这里可以看到这些变量 692 00:35:52,217 --> 00:35:55,952 clicking on "self", face view, sure enough nil. +点击 self，faceView 确实为nil 693 00:35:55,954 --> 00:35:58,822 So my pointer to my face view has not been set yet by iOS +在 iOS 中，这里的 faceView 还没有被设置 694 00:35:58,824 --> 00:36:01,725 and that's always gonna be the case when you're preparing so +在你准备 segue 时，这种情形经常发生 695 00:36:01,727 --> 00:36:05,529 be prepared for that happening okay. So what can we do about - +所以，我们应该怎么做呢？ 696 00:36:05,531 --> 00:36:10,066 it here? Okay well one thing we could say if face view does +我们可以设置如果 faceView 不为空 697 00:36:10,068 --> 00:36:14,738 not equal nil then we'll do all this updating UI stuff +我们来更新这些 UI 698 00:36:14,740 --> 00:36:17,874 right? K, by the way why is this happening, +顺便说下，为什么会这样呢？ 699 00:36:17,876 --> 00:36:20,644 why are we on this line of code? If we look over here on +这行代码怎么了？ 700 00:36:20,646 --> 00:36:22,946 the left it'll show us how us we got here. +如果我们看左边的展示给我们的信息 701 00:36:22,948 --> 00:36:24,915 Okay, so we're in this place right here, +然后再看对应的右边的代码 702 00:36:24,917 --> 00:36:28,919 okay, and let's see how we got here by clicking here. See, +我们点击一下看看这是什么 703 00:36:28,921 --> 00:36:33,156 we set our model which makes sense and it called up DUI, so +看，这里我们设置了我们的 model，然后更新了UI 704 00:36:33,158 --> 00:36:36,626 why are we setting our model, okay, let's go up more. Sure +为什么会走这一行呢，我们朝上点 705 00:36:36,628 --> 00:36:39,563 enough here we are preparing. Okay, setting our model. +因为在这里我们 prepare segue 706 00:36:39,565 --> 00:36:42,566 So this is right, preparing for segway, goes in here set +然后设置了model 707 00:36:42,568 --> 00:36:45,302 to our model. Wants to update UI, it's great. +设置了model 之后，更新UI 708 00:36:45,304 --> 00:36:48,271 Unfortunately our view is not been connected via outlet. +不幸的是，这里我们的view没有连接 outlet 709 00:36:48,273 --> 00:36:50,840 All right, so this is one way we could do it. By the way, +我们可以这样设置，避免他为空 710 00:36:50,842 --> 00:36:53,443 there is another trickier way to do it which is to +顺便说一下，还有另一个复杂的方法处理这个问题 711 00:36:53,445 --> 00:36:55,312 use question mark here. +在这里用问号 712 00:36:55,314 --> 00:36:57,981 You know that question mark works for optional chaining, +你们知道在等号的右手边处理 713 00:36:57,983 --> 00:36:59,683 right, on the right hand side of an equals? +用问号来处理可选链 714 00:36:59,685 --> 00:37:02,452 It also works on the left hand side. If you put a question +在等号的左边也可以处理 715 00:37:02,454 --> 00:37:05,155 mark there, that's and you can put as many of the question +你可以在等号的左边放置 716 00:37:05,157 --> 00:37:07,457 marks as you want on the left side of an equals. And +你希望放置的任意的问号 717 00:37:07,459 --> 00:37:10,760 if any of the things that you put a question mark are nil, +如果你在其后写问号的变量确实为空 718 00:37:10,762 --> 00:37:12,395 it just ignores the whole statement. +他会忽略掉整个状态 719 00:37:12,397 --> 00:37:15,799 Like it didn't even happen. Okay. So, that would be +就像没写这句话一样，这就是另一种方式了 720 00:37:15,801 --> 00:37:17,534 another way. But we would have to put a question mark on +但是我们需要在这里的每一个 faceView 721 00:37:17,536 --> 00:37:20,437 every single access of faceview in here. So, +后面都写上问号 722 00:37:20,439 --> 00:37:23,807 we might as well just check to see if it's not nil. Now, is +所以，还不如我在上面检查一下 faceView 是否为空 723 00:37:23,809 --> 00:37:28,011 this going to fix our problem? And the answer is, yes it is. +现在让我们看看这确实解决了我们的问题了没 724 00:37:28,013 --> 00:37:31,681 Because we do update UI when our model gets set, but +确实解决了，因为在 model 被重新设置后需要更新UI 725 00:37:31,683 --> 00:37:37,621 we also do update UI when this outlet gets set, remember? +我们需要在outlet被设置后，更新UI, 记得吗？ 726 00:37:37,623 --> 00:37:40,523 So when the outlet later, after the prepare is done, +所以，当outlet被设置后，准备好了 727 00:37:40,525 --> 00:37:42,926 when the outlet comes along and gets set, boom, - +outlet被设置了 728 00:37:42,928 --> 00:37:46,162 our UI will get updated with the model that we set during +我们的 UI 界面被更新为我们设置的 model 729 00:37:46,164 --> 00:37:49,065 prepare, okay? So it's going to work fine, okay? +这里就会正确运行，对吧？ 730 00:37:49,067 --> 00:37:52,569 But this is part of the reason why when our outlets get set, +这就是为什么我们设置了 outlet 731 00:37:52,571 --> 00:37:54,838 we update UI and when our model gets set, +更新了UI 然后这时 model 才设置 732 00:37:54,840 --> 00:37:58,208 we update our UI because the order of them happening can be +我们更新 UI，因为这两项发生的顺序 733 00:37:58,210 --> 00:38:02,846 you know can vary. All right. Sound good alright. +有时候是不同的，看起来就应该这样 734 00:38:02,848 --> 00:38:04,347 So we fixed that, we checked this so +现在我们解决了这个问题，我们来检查下 735 00:38:04,349 --> 00:38:06,483 it's not gonna crash anymore, so let's run and +还会不会崩溃 736 00:38:06,485 --> 00:38:08,318 hopefully this is all working like a charm now. +我们运行一下，希望一切正常 737 00:38:08,320 --> 00:38:12,222 All right here we go ready? Angry, +现在看看对不对，Angry， 738 00:38:12,224 --> 00:38:16,192 happy, worried, mischievous. +happy, worried, mischievous. 739 00:38:16,194 --> 00:38:19,929 Okay. All right? So it's working great. Okay, and +运行起来很好 740 00:38:19,931 --> 00:38:26,002 let's try it this way. Slide out. Angry, happy, right? +现在我们这么做，侧滑，Angry, happy 741 00:38:26,338 --> 00:38:30,473 Working like a charm. Okay? Okay, all right. +看起来很好看，好的 742 00:38:30,475 --> 00:38:35,111 Now, what about iPhone? Okay, this is great on iPad. +现在，在 iPhone 上是什么样子呢？在 iPad 上运行良好 743 00:38:35,113 --> 00:38:38,248 Let's try running this on iPhone, and see what we get. +我们试着在 iPhone 上运行，看看是什么样 744 00:38:45,991 --> 00:38:48,525 All right, here's our thing. We got it here. Let's try +好的，我们的模拟器在这里 745 00:38:48,527 --> 00:38:53,496 happy. All right, we're happy! Actually, now we're not so - +让我们尝试点击 happy，对的 happy + 746 00:38:53,498 --> 00:38:57,100 happy because we're stuck. Okay, there's no way for +事实上，我们没有很开心，因为我们卡住了 747 00:38:57,102 --> 00:39:00,437 me to get back to choosing something else. Okay, I could +我没有办法返回去选择其他东西 748 00:39:00,439 --> 00:39:04,274 try rotating. No. I can try sliding out from the left. +我尝试着旋转，不行，我从左边滑动 749 00:39:04,276 --> 00:39:09,579 Nope, no. OK, split view does not split on an iPhone. +也不行，splitViewController 在 iPhone 上是不能分开的 750 00:39:09,581 --> 00:39:11,715 Only on the iPhone 6 Plus, which is +只有在 iPhone 6 Plus 上可以运行 751 00:39:11,717 --> 00:39:13,550 the only one big enough to really do it, +iPhone 6 Plus 是唯一一个够大的机型来展示 splitViewController 752 00:39:13,552 --> 00:39:16,419 okay? So we're stuck here. So this UI that we have in our +所以，我们卡住了，在故事板中这套 UI 不能正常的运行在 753 00:39:16,421 --> 00:39:19,122 storyboard is no good for iPhone, okay? Now we can still +iPhone里，我们现在仅仅可以 754 00:39:19,124 --> 00:39:21,491 make our guy blink, okay? But that's all we can do. +设置小人眨眼，但是我们只能做着一件事 755 00:39:21,493 --> 00:39:24,060 So unless we're happy just watching him blink all day +除非我们看着他光眨眼就满意了 756 00:39:24,062 --> 00:39:27,130 we need to fix this. So how are we gonna make this work on +我们需要解决这个问题，怎么让这个功能在 757 00:39:27,132 --> 00:39:30,800 iPhone? Okay. First we have to ask ourselves what would be +iPhone上也能正确运行呢？首先，我们需要思考 758 00:39:30,802 --> 00:39:32,902 an appropriate UI on iPhone. Okay, +在 iPhone 上的合适 UI 759 00:39:32,904 --> 00:39:35,538 and this is where navigation controller comes in. - +这里就需要用到 navigationController 了 760 00:39:35,540 --> 00:39:37,507 Navigation controller would be great here because +NavigationController 用在这里会很合适 761 00:39:37,509 --> 00:39:40,777 you start the stack of cards with the angry mischievous +现在有一叠代表生气、淘气、担心的视图 762 00:39:40,779 --> 00:39:44,814 worried MVC. And then when you click the face it puts +当你另外点击了一个 face ，它将 763 00:39:44,816 --> 00:39:47,217 a new card on top which is the face. And then if +一个新的视图放在这个 face 之上 764 00:39:47,219 --> 00:39:49,786 you want a different one you just hit back, throw that card +然后，如果你想换一个表情，你只需返回 765 00:39:49,788 --> 00:39:52,756 away, and you are back to the angry mischievous worry choice +将之前的 face 扔掉，你就回到之前选择表情的视图了 766 00:39:52,758 --> 00:39:54,557 again, right? Okay, so it's perfect, okay, +对吗？这样很好 767 00:39:54,559 --> 00:39:57,193 navigation controller would be a perfect UI. So we need to +navigationController 是一个完美的 UI 控件 768 00:39:57,195 --> 00:40:00,830 put navigation controller into our story board, okay. So +所以我们需要将 navigationController 放进故事板中 769 00:40:00,832 --> 00:40:05,301 let's do that. Let's go back to our story board over here. +我们回到故事板 770 00:40:05,704 --> 00:40:06,703 There's a lot of space here. +把编辑空间弄大一点 771 00:40:06,705 --> 00:40:10,740 So where I'm gonna put this navigation controller? Well, +我应该把 navigationController 放哪儿呢？ 772 00:40:10,742 --> 00:40:15,278 you really need one navigation controller around the root. +我们确实应该一个根控制器外放置一个 navigationController 773 00:40:15,280 --> 00:40:18,314 View controller. The base card, cards at the bottom. +这是最底下的 controller，在一叠 controller 下面 774 00:40:18,316 --> 00:40:21,251 Okay? So I can put a navigation controller here in +我可以像放置其他控件那样，从这里取出控件，然后放置 775 00:40:21,253 --> 00:40:24,154 the same way I put these other things by going down here. You +我可以这么放置 navigationController 776 00:40:24,156 --> 00:40:26,723 can see there's a navigation controller right here. +你可以看到，这个就是 navigationController 777 00:40:26,725 --> 00:40:28,758 I could drag it out. I could control, drag, +我可以把他拖出来，按住 control，然后 drag 778 00:40:28,760 --> 00:40:32,429 etc. There's actually a cooler way to do it, which is select +确实还有更酷的方法来做这件事 779 00:40:32,431 --> 00:40:36,232 your route MVC which is this guy. That's the card that's +先选中根控制器，就是这个 780 00:40:36,234 --> 00:40:39,068 at the bottom of the stack and go up to editor and +这个就是一叠视图中最下面的那个 781 00:40:39,070 --> 00:40:42,205 just like you did in bed and stack view, do embed and +然后选中 editor，就像把控件放进 stackView 中一样选中 embed in 782 00:40:42,207 --> 00:40:44,073 negotiation controller. You can also do it for +然后选择 navigationController，你也可以通过这种方式 783 00:40:44,075 --> 00:40:47,210 tab bar by the way, but do a navigation controller. +来添加 Tab Bar Controller，我们先选择 navigationController 784 00:40:47,212 --> 00:40:51,381 Now watch what happens here, boom! You put this +看看发生了什么，boom！ 785 00:40:51,616 --> 00:40:55,318 inside a navigation control automatically wired it up. +这个控制器自动封装进了 navigationController 786 00:40:55,320 --> 00:40:58,855 Now whats kind of interesting about this is, it also made +特别有趣的是，它会自动将 787 00:40:58,857 --> 00:41:01,491 that navigation controller be the master of the split view. +navigationController 变为 splitView 中的 master 788 00:41:01,493 --> 00:41:03,927 In other words, it kind of wrapped the navigation +换句话说，它将根控制器包裹进 navigationController 789 00:41:03,929 --> 00:41:07,163 controller around the root con, the root view controller +而根控制器还保留了 790 00:41:07,165 --> 00:41:09,866 and kept that pointer to the master. So +之前作为 master 的指针 791 00:41:09,868 --> 00:41:14,204 now the master is actually a navigation controller, - +所以，master 实际上就是一个 navigationController 792 00:41:14,206 --> 00:41:17,974 with this as it's root view controller. Still all these +这个控制器作为根控制器 793 00:41:17,976 --> 00:41:20,643 segways are still here. Okay, these segues are still, +而且还保留着这些 segues 794 00:41:20,645 --> 00:41:23,079 they didn't it didn't undo any of these segues. And +这些 segues 并没有被撤销 795 00:41:23,081 --> 00:41:28,485 this is still the detail of the split-view controller. +这个控制器还是原来split-view controller 中的 detail 796 00:41:28,687 --> 00:41:29,018 @@ -3185,818 +3471,1018 @@ this is still the detail of the split-view controller. 797 00:41:29,020 --> 00:41:31,087 I selected this, which is my root-view-controller, +我选中根控制器 798 00:41:31,089 --> 00:41:36,159 and I went to editor, embed in, navigation controller. +然后选择 editor -> embed in -> navigationController 799 00:41:36,161 --> 00:41:40,663 Okay? So, now this is an interesting set up right here. +做这些挺有意思的 800 00:41:40,665 --> 00:41:43,099 Let's see if just fixed it, maybe it will just work. +现在，看看刚刚做的有没有起作用 801 00:41:43,101 --> 00:41:44,000 Because, you know, I hear, +因为，你知道的 802 00:41:44,002 --> 00:41:46,769 I got this, in a navigational controller, right now, so - +我刚刚得到了一个 navigationController 803 00:41:46,771 --> 00:41:47,904 it should just work on a iPhone, right? +他会不会只在 iPhone 中生效呢？ 804 00:41:47,906 --> 00:41:53,743 Let's try it. How many people think this going to work? +有多少人认为会起作用？ 805 00:41:53,745 --> 00:41:56,246 Raise your hand if you think this is going to work. +如果你觉得会起作用，请举起手 806 00:41:56,248 --> 00:42:01,150 Nobody thinks it's gonna work. It is going to work! Gotcha. +没有人觉得这会起作用吗，事实上，会起作用的！ 807 00:42:01,152 --> 00:42:03,186 Okay. So here I am in my navigation controller. +现在我看到的是 navigationController 808 00:42:03,188 --> 00:42:06,489 I'm going to go back. Here is my stuff. Let us try worried. +点击返回，这是选择表情的，点击担心的 809 00:42:06,491 --> 00:42:09,492 He looks worried. I am not worried though cuz I know it +确实看起来很担心，我倒不会再担心了 810 00:42:09,494 --> 00:42:14,364 is going to work. Okay so this worked fine, exactly what +因为我知道这起作用了 811 00:42:14,366 --> 00:42:18,001 we want on iPhone. Now my question to you is, +iPhone 上运行良好，我的问题来了 812 00:42:18,003 --> 00:42:21,604 is this still going to work on iPad? Okay. +在 iPad 上会起作用吗？ 813 00:42:21,606 --> 00:42:25,308 Let's go look at that. Let's go back to iPad. +我们来看看在 iPad 上 814 00:42:25,310 --> 00:42:28,344 How many people think it's going to work on iPad still. +有多少人觉得在 iPad 上也会同样起作用呢？ 815 00:42:28,346 --> 00:42:31,848 One. Two. Three. You guys are getting smart. Yes. +一，二，三，你们变聪明啦 816 00:42:31,850 --> 00:42:33,082 It's still going to work on iPad. +是的！在 iPad 上也会起作用 817 00:42:33,084 --> 00:42:36,419 Okay. It's pretty cool the way they made this work so you can +只在一个故事板中构建页面，但是能运行在 818 00:42:36,421 --> 00:42:39,789 build one storyboard that'll work fine on both platforms. +不同的平台上，确实是一件很酷的事情 819 00:42:39,791 --> 00:42:43,626 So here we go, this is iPad, we can turn it around, +现在，这是 iPad，转过来 820 00:42:43,628 --> 00:42:46,329 here it is, it is in a navigation controller, +页面在一个 navigationController 中 821 00:42:46,331 --> 00:42:48,264 you see? Which is actually kind of nice, cuz I can put +你们看到了没？这样确实很好 822 00:42:48,266 --> 00:42:53,403 a nice title in here for this MBC, okay. But when I click in +因为我可以在这上面写一个标题 823 00:42:53,405 --> 00:42:57,307 here, it's not going to slide a deck onto the deck of cards, +当我点击时，这个视图并不会侧滑出视线 824 00:42:57,309 --> 00:43:00,743 it's going to do the show detail, right, angry, happy, +它会正确显示 detail ，生气的、高兴的 825 00:43:00,745 --> 00:43:05,381 worried, mischievous. Okay? Everyone got that, +担心的、淘气的，对吗？大家明白 826 00:43:05,383 --> 00:43:08,651 how we do that? Now this kind of structure, +我们怎么做了吗?这是一种结构 827 00:43:08,653 --> 00:43:12,221 we have split view, navigation controller, and +我们先有 splitViewController, navigationController 828 00:43:12,223 --> 00:43:14,357 then the content for your master, and +然后是 master 的内容 829 00:43:14,359 --> 00:43:16,826 then the detail right here. Very common to build this, +然后是 detail 的内容，这是通常的做法 830 00:43:16,828 --> 00:43:18,928 because if you're building an app that works on both, +因为，如果你在做一个app，这是常规的做法 831 00:43:18,930 --> 00:43:22,298 this is what it's gonna look like basically. All right, +这是非常基本的操作 832 00:43:22,300 --> 00:43:22,498 so I'm gonna show you one +现在，我要向你展示 833 00:43:22,500 --> 00:43:26,402 last thing here of interest, which is these titles, okay. +这里最后一个有趣的点，就是标题 834 00:43:26,404 --> 00:43:31,874 So we have this little space for a title up here, so +我们这里给标题留了一个小空间 835 00:43:31,876 --> 00:43:35,445 I'd like to put a title here, okay. And how do I put a title +我要在这儿放置标题，我怎么在这儿放标题呢？ 836 00:43:35,447 --> 00:43:37,647 up here? Again, remember that's object oriented, okay. +记住，这一切都是面向对象的 837 00:43:37,649 --> 00:43:41,250 That title comes from whatever MVC happens to be showing in +这些标题会在 navigationController 838 00:43:41,252 --> 00:43:43,019 this navigation controller at the time. So +展现MVC 的时候出现 839 00:43:43,021 --> 00:43:46,289 I go to the storyboard, to that MVC, which is this one, +我打开故事板，选择这个 MVC 840 00:43:46,291 --> 00:43:48,591 and could just double click on it, okay? So +双击一下，对吗？ 841 00:43:48,593 --> 00:43:53,296 we'll call this one Emotions, okay. So now if I run, +标题叫做 Emotions ，如果我运行下 842 00:43:57,535 --> 00:43:58,368 I get a nice title up here, +我得到一个很好地标题 Emotions 843 00:43:58,370 --> 00:44:03,840 Emotions. What if I wanted a title over here? Okay, +如果这里也想有个标题呢？ 844 00:44:03,842 --> 00:44:07,844 how would I do it if I wanted a title over here? +如果这个位置也想有标题，我应该怎么做呢？ 845 00:44:08,079 --> 00:44:09,512 Well if you look on the iPhone, +你看在 iPhone 中 846 00:44:09,514 --> 00:44:13,650 okay if we go back and oops, run this on iPhone. +返回，要运行在 iPhone中 847 00:44:14,853 --> 00:44:19,122 Since both MVCs are in that navigation controller, +因为这些 MVC 都在navigation controller 848 00:44:19,124 --> 00:44:24,727 they both have titles Okay, so if I go here, here's emotions, +所以他们都有标题，这里有标题emotions 849 00:44:24,729 --> 00:44:28,865 angry. Look, there's room for a title up here. But +这里也有标题 850 00:44:28,867 --> 00:44:34,170 back on the iPad, that's not the case because the detail, +但是，回到 iPad 上，这里就没有标题了 851 00:44:34,172 --> 00:44:37,573 when you replace the detail it doesn't actually put it +因为，在 iPad上，当你换到 detail 页面时 852 00:44:37,575 --> 00:44:40,543 inside the same navigation controller that the master is +detail 并没有被包裹进 master 在的那个 navigationController 853 00:44:40,545 --> 00:44:44,247 in. So the master is in a navigation controller, but +所以，master 在 navigationController 中 854 00:44:44,249 --> 00:44:47,417 this is not. So if we wanted a title here, +而 detail 并不在，所以如果我们想要设置标题 855 00:44:47,419 --> 00:44:49,752 we have to put this guy in a navigation controller. +我们就需要把 detail 放进 navigationController里 856 00:44:49,754 --> 00:44:52,488 Even though we're not going to use the navigation controller +如果我们就是想用 navigationController 来展示个标题 857 00:44:52,490 --> 00:44:55,858 for anything except for the title on the split view case. +并不做其他事情，在 splitViewController 里 858 00:44:55,860 --> 00:44:56,392 We would still have to do it. +我们还得用 navigationController 来做 859 00:44:56,394 --> 00:45:01,264 And in fact, iOS makes it so that just works, okay? +事实上， iOS 就是这么设计的 860 00:45:01,266 --> 00:45:04,634 So I'm going to go here. Down to this guy. Okay and +所以，点击这个 controller 861 00:45:04,636 --> 00:45:09,706 I'm going to embed him in a navigation controller okay. +把他包裹进一个 navigationController 862 00:45:09,708 --> 00:45:12,475 So just have this, I have the face selected, +就这么做，点击一个表情 863 00:45:12,477 --> 00:45:17,280 embed puts him in there, okay. Now this +把他放进了一个 navigationController 里 864 00:45:17,282 --> 00:45:20,116 almost is going to work, okay, if we look at what this looks +如果我们运行看看这样设置是什么样的 865 00:45:20,118 --> 00:45:23,119 like. Okay? There's a little bit of an issue here because +可能是运行正常，可能有一些问题 866 00:45:23,121 --> 00:45:26,889 these segues are now going to this navigation controller. +因为这些 segues 现在开始指向 navigationController 867 00:45:26,891 --> 00:45:32,028 But let's take a look at what it looks like anyway. Okay, +我们还是看一下到底运行的怎么样吧 868 00:45:32,030 --> 00:45:34,363 on iPad look, they're both in navigation controller. +在 iPad 上，确实都在 navigation controller 里 869 00:45:34,365 --> 00:45:37,633 So I've room for a title here now, okay? And if I click, +我挪点空间来看看 870 00:45:37,635 --> 00:45:41,838 it doesn't work anymore. Okay, so I broke it by putting this +如果我点击了，这个表情并没有真正展现 871 00:45:41,840 --> 00:45:44,941 in a navigation controller. Now why, and by the way, +当我把它放置在 navigation controller 里了，反而破坏了这个表情 872 00:45:44,943 --> 00:45:47,944 does it work on iPhone? Yes, still works on iPhone. So +顺便看一下，在 iPhone 中正常吗？看起来很正常 873 00:45:47,946 --> 00:45:51,647 it did not break it on iPhone because iOS is smart +它没有破坏在 iPhone 上的显示，因为 iOS系统够聪明 874 00:45:51,649 --> 00:45:54,951 enough to know this is already in a navigation controller, so +它知道这个控制器已经在 navigation controller 里了 875 00:45:54,953 --> 00:45:57,453 I'm just gonna ignore this navigation controller and +所以在展示它时，会忽略它自己的那个 navigation controller了 876 00:45:57,455 --> 00:46:01,691 put this in here. See? So this looks the same, no change, +看到了吗？这看起来没啥不一样的 877 00:46:01,693 --> 00:46:02,825 still in a navigation controller. +仍然在 navigation controller 中 878 00:46:02,827 --> 00:46:05,361 iOS didn't put a navigation controller inside a navigation +iOS 不会将一个 navigation controller 放在另一个 navigation controller 里 879 00:46:05,363 --> 00:46:08,498 controller, in fact iOS never puts a navigation controller +事实上，iOS 永远都不会将一个 navigation controller 880 00:46:08,500 --> 00:46:10,299 inside another one. Okay, if it sees and +放在另一个 navigation controller 里 881 00:46:10,301 --> 00:46:12,235 encounters another one, it just ignores that one, +如果它发现它包裹在另一个 navigation controller 里，它会自动忽略它 882 00:46:12,237 --> 00:46:14,170 okay. It's like you're either in one or you're not, +你可以把它放进一个 navigation controller 之中或者不放 883 00:46:14,172 --> 00:46:15,972 you can't be in two at the same time. So +但是你不能同时包裹两个 navigation controller 884 00:46:15,974 --> 00:46:20,042 it worked great on the iPhone. So why did it break though? +所以，在 iPhone 中运行良好，但是，为什么崩溃了呢？ 885 00:46:20,044 --> 00:46:22,145 Sorry, it worked great visually but it still, +它看起来运行良好，但是 886 00:46:22,147 --> 00:46:24,413 I didn't show it there but it didn't work to click. +在点击时，运行的并不良好 887 00:46:24,415 --> 00:46:26,549 Okay, just like in the iPad it didn't work to click. And - +跟在 iPad 里一样，点击后效果不对 888 00:46:26,551 --> 00:46:30,019 why didn't it work to click? Well, we have to understand or +为什么点击的效果不对呢，这里我们必须了解或者 889 00:46:30,021 --> 00:46:32,955 prepare a little bit better there, okay? +准备了这点知识 890 00:46:32,957 --> 00:46:35,525 And in fact, let's take the time to do this. +事实上，会耗费我们一点时间来说明这个问题 891 00:46:35,527 --> 00:46:37,160 I'm gonna go in the debugger and show you this. +我将在 debugger 模式下说明这个问题 892 00:46:37,162 --> 00:46:40,797 So I'm gonna set a break point right here, okay? +我需要在这里打个断点 893 00:46:40,799 --> 00:46:43,199 In prepareForSegue because prepareForSegue is not +在 prepareForSegue 这个方法里打断点 894 00:46:43,201 --> 00:46:48,204 properly preparing that thing. So let's see why it's failing. +因为它没有很好地为这个 segue 做准备，我们来看看为什么失败了 895 00:46:53,044 --> 00:46:56,712 All right, so here we go. I'm going to hit happy. And +我们准备好了，运行，点击 happy 896 00:46:56,714 --> 00:46:59,015 it's going to break, okay, at this prepare. +到断点这里了，在 prepareForSegue 里面 897 00:46:59,017 --> 00:47:02,285 So it's trying to prepare that thing to be happy. And +所以，它准备为展示 happy 做一些事 898 00:47:02,287 --> 00:47:06,022 what is, let's look at this destination VC right here. +在这里看看 destinationVC 899 00:47:06,024 --> 00:47:11,794 Look what its type is. It's a UN navigation controller. +看看它的类型是什么，这是个 UINavigationController 900 00:47:11,796 --> 00:47:13,896 And that kind of makes sense, right? +这说明了一些问题，是吗？ 901 00:47:13,898 --> 00:47:15,531 Because if you look at our storyboard, +因为在 storyboard 中 902 00:47:15,533 --> 00:47:19,669 these segues are going down to this navigation controller. +这些 segue 指向这些 navigation controller了 903 00:47:19,671 --> 00:47:21,938 Okay? So that's just a little bit of a twist. +所以这看起来有点纠结 904 00:47:21,940 --> 00:47:25,741 A little bit tricky. And all we have to do is look at this +有点复杂，我们需要判断这个 destinationvc 905 00:47:25,743 --> 00:47:28,811 destination VC and if it's a navigation controller, +如果他是一个 navigation controller 906 00:47:28,813 --> 00:47:32,381 then let's get moving inside of it. Okay. And +我们需要获得它里面包裹的东西 907 00:47:32,383 --> 00:47:36,519 work on that. Okay. So I'm just going to say here, +让我们这样做吧，我得在这里说明 908 00:47:36,521 --> 00:47:39,755 if I can let Navcon, which is a local variable, +写一个局部变量，navcon 909 00:47:39,757 --> 00:47:44,393 equal the destination VC as a UI navigation controller. So, +如果将 destinationvc 作为一个 UINavigationController 赋值给 navcon 910 00:47:44,395 --> 00:47:49,165 if the destination happens to be UINavigationController, +如果 destinationvc 确实就是一个 UINavigationController 911 00:47:49,167 --> 00:47:54,270 then I'm gonna let I'm just gonna set the destination VC +我将这个 destinationvc 等于这个 912 00:47:54,272 --> 00:47:58,307 equal to the navcon.visibleViewController. +navcon 的 visibleViewController 913 00:47:58,309 --> 00:47:59,942 Which is optional, so I'm gonna, +这是一个可选值，我打算 914 00:47:59,944 --> 00:48:01,277 actually I won't even unwrap it. +事实上，我不是要将它解包 915 00:48:01,279 --> 00:48:03,479 I'm gonna say if it's visible view control and +而是，如果它就是一个 visibleViewController 916 00:48:03,481 --> 00:48:06,048 if the navigation control doesn't have a visible view +或者这个 navigationController 没有 visibleViewController 917 00:48:06,050 --> 00:48:09,252 control then we'll just leave it to be the destination view +它会直接赋值为自身 918 00:48:09,254 --> 00:48:13,823 controller. This'll have to be bar. Okay? So +这样做更保险，是吗？ 919 00:48:13,825 --> 00:48:16,959 here all I'm doing is, I'm just saying if I'm preparing +我要写的就是这些，如果在准备这个 segue 时 920 00:48:16,961 --> 00:48:19,695 to segue to something and it's a navigation controller, +它是一个 navigationController 921 00:48:19,697 --> 00:48:22,365 then instead look inside the navigation controller and +我会获取到 navigationController 里面的东西 922 00:48:22,367 --> 00:48:26,135 segue to that instead. Okay? Prepare that instead. Okay? +segue 会指向里面的 controller ，为展示这个做准备，是吗？ 923 00:48:26,137 --> 00:48:29,038 Everyone understand what I'm doing there with these, this +大家都明白我在这里写了什么吗？ 924 00:48:29,040 --> 00:48:37,647 little Three lines of code? >> [INAUDIBLE] +明白我写的这三行代码吗？ 925 00:48:37,649 --> 00:48:38,447 >> Yes, so you're +对，你说 926 00:48:38,449 --> 00:48:39,048 saying, could I go +我能不能 927 00:48:39,050 --> 00:48:40,049 back here in the storyboard and +在 storyboard 做我刚刚写下的操作 928 00:48:40,051 --> 00:48:43,452 have all these segue things go down over this way instead? +将这些 segue 直接指向展示的 controller？ 929 00:48:43,454 --> 00:48:44,086 You wouldn't actually want that, +事实上，你不会想这么做的 930 00:48:44,088 --> 00:48:47,523 because when the segue creates the MVC that it's gonna show, +因为当 segue 创造的这些 MVC 准备去展示时 931 00:48:47,525 --> 00:48:49,692 you want it to create a navigation controller. So +你希望他在一个 navigationController 里 932 00:48:49,694 --> 00:48:51,827 you actually want it to go into this navigation. +所以你希望在一个 navigationController 里看到那个 controller 933 00:48:51,829 --> 00:48:54,530 It's just that, when it comes to preparing it, you don't +这样当你准备展示它时 934 00:48:54,532 --> 00:48:56,365 really want to prepare the navigation controller, +你不是想为展示那个 navigationController 做准备 935 00:48:56,367 --> 00:48:58,567 you wanna prepare the thing inside. So +而是为 navigationController 里面的东西做准备 936 00:48:58,569 --> 00:49:02,104 that's why we're in this code just looking inside +这就是为什么我们在这些代码里 937 00:49:02,106 --> 00:49:04,206 the navigation controller to make the destination +将 destinationvc 赋值为 navigationController 里包裹的东西 938 00:49:04,208 --> 00:49:07,576 that we're preparing be the thing inside. Okay? +我们为里面的东西做准备，对吗？ 939 00:49:07,578 --> 00:49:10,613 So little trickiness. You'll often have this little code. +有一点点难，你会经常写这种代码 940 00:49:10,615 --> 00:49:12,381 I'll actually show you later in the quarter kind of +事实上，一会儿我会用 941 00:49:12,383 --> 00:49:16,585 a little more sophisticated way to put this in there. +一个更常用的方法来设置这个 942 00:49:16,587 --> 00:49:21,824 You can put it there with one syntactical element, +你可以用一个更语义性的元素 943 00:49:21,826 --> 00:49:25,628 it's possible, but this I want to leave explicitly so +但是，我想更明确的设置这个 944 00:49:25,630 --> 00:49:29,065 you understand what's going on here. So now when we run it's +你也会明白这里做了什么，现在，我们运行一下 945 00:49:29,067 --> 00:49:32,101 going to work because when we segue to something +看看是否工作，因为我们在这里将 segue 指向了 946 00:49:32,103 --> 00:49:35,604 that's navigation controls, it can look inside. See, angry, +navigationController 里面的东西 947 00:49:35,606 --> 00:49:39,442 happy, worried, mischievous. And the last thing I wanna do +看看， angry、happy、worried、mischievous 都正确的展示了 948 00:49:39,444 --> 00:49:43,346 is set this title right here. Now this title was fixed. +我需要做的最后一件事就是设置 controller 的标题 949 00:49:43,348 --> 00:49:45,247 This is always the emotions MVC. +这需要在展示表情的 MVC 里设置标题 950 00:49:45,249 --> 00:49:49,285 But this MVC, its title kinda depends on what it's showing +但是这个 MVC，它的标题像是需要在展示它的地方来设置 951 00:49:49,287 --> 00:49:52,054 here, doesn't it? Alright like if we are showing angry it - +是这样吗？就像是，如果我们要展示 angry 952 00:49:52,056 --> 00:49:53,556 would be nice if this title would be angry. +它的标题就是 angry，这样应该很不错 953 00:49:53,558 --> 00:49:55,958 It would be nice if this title were worried. +展示 worried 时，它的标题就是 worried 954 00:49:55,960 --> 00:49:59,662 Okay? So where can we get the appropriate title here? +所以，我们得在哪里获得这个对应的标题呢？ 955 00:49:59,664 --> 00:50:02,098 we'll we can get it form the button that's asking us +我们可以从引发 segue 的按钮那里获得标题 956 00:50:02,100 --> 00:50:05,935 to segue. Right? If this angry button asks us to segue then +对吗？如果是这个 angry 按钮让我们来展示表情 957 00:50:05,937 --> 00:50:10,773 let's set this title to be the title of the angry button. +我们就将标题设置为这个 angry 按钮的标题 958 00:50:10,775 --> 00:50:15,911 Right? So, looking back here, in our "prepareForSegue". +对吗？回到 prepareForSegue 这里 959 00:50:15,913 --> 00:50:20,216 Is that title of the angry button available to us here? +我们可以用 angry 按钮的标题吗？ 960 00:50:20,218 --> 00:50:25,087 Where? Where can I get it? From "sender", yeah, exactly. +在哪里，在哪里我能获得这个标题呢？ sender！ 961 00:50:25,089 --> 00:50:26,922 Okay. You guys are getting it. That's really good. +对的，你们已经明白这一点了，很好 962 00:50:26,924 --> 00:50:29,859 Sender is the button that's causing the segue to happen. +Sender 就是那个引发 segue 的按钮 963 00:50:29,861 --> 00:50:32,661 That's gonna be the angry button. So, it's any object. +这应该就是那个 angry 按钮，这可以是任何对象 964 00:50:32,663 --> 00:50:35,197 So I'm gonna have to cast it to be a button. But that's no +所以，我想让它转型为一个 button，这没什么问题 965 00:50:35,199 --> 00:50:38,734 problem. I'm just gonna say if I can let the sending button +我要写如果我让 sending button 作为一个 UIButton 966 00:50:38,736 --> 00:50:41,937 equal the sender as a UI button, okay? And +等于 sender，对吗？ 967 00:50:41,939 --> 00:50:45,307 if not, if I'm segueing from code or something here, +如果它不能转为一个UIButton，或者我是用代码 968 00:50:45,309 --> 00:50:45,741 then this is not gonna work. +或者其他方法引发的 segue ，这样就不能正常工作了 969 00:50:45,743 --> 00:50:48,677 But so what. Okay? We just won't get the title we want. +我们就不能给 Face View Controller 970 00:50:48,679 --> 00:50:52,748 On our Face View Controller. But if it is then I can just +获取到我们想要的标题，如果能转为 UIButton 971 00:50:52,750 --> 00:50:58,087 set the Face View Controllers navigation item. Does everyone +我可以设置给 Face View Controller 设置它的 navigation item 972 00:50:58,089 --> 00:51:00,656 remember what navigation item is? It's kind of just a bundle +大家都记得 navigation item 吗？他就像一捆东西 973 00:51:00,658 --> 00:51:04,293 of things like a little bag of goodies that the navigation +像是 navigation controller 在展示它里面的 MVC时 974 00:51:04,295 --> 00:51:08,197 controller looks inside of when that MVC is showing. +navigationController 有的一袋东西 975 00:51:08,199 --> 00:51:13,602 To get information like the buttons or the title, okay. +为了得到这个 button 的属性，比如 title 976 00:51:13,604 --> 00:51:19,208 Equals the sending button's current title, +等于这个触发 button 的当前标题 977 00:51:19,210 --> 00:51:22,912 okay. So this little bag of goodies, navigation item, +我们在文档中看一下 978 00:51:22,914 --> 00:51:25,281 here let's look at it in the documentation, okay. +这一袋 navigationItem 里的东西 979 00:51:25,283 --> 00:51:28,250 I'm going to go here. The I View Controller, +我要打开这个，这是 ViewController 980 00:51:28,252 --> 00:51:29,218 it's like a navigation item. +这是那些 navigationItem 981 00:51:29,220 --> 00:51:31,754 You can see it house things like the title to show +你可以在目录里看到 title 982 00:51:31,756 --> 00:51:35,891 when this MVC is showing in the navigation controller. +当 MVC 在 navigationController 中展示时 983 00:51:35,893 --> 00:51:39,962 Back bar button item to use instead of the default one. - +Back bar button item 就是默认的 984 00:51:39,964 --> 00:51:42,765 Left bar button items and right bar button items. +Left bar button item 和 right bar button item 985 00:51:42,767 --> 00:51:45,101 You can put you know things on the top, left and right. +你可以将你获得的东西放在上面，左面或者右面 986 00:51:45,103 --> 00:51:46,902 That's what's in this little bag of goodies. And +这就是这一袋东西里面的 987 00:51:46,904 --> 00:51:50,172 this bag of goodie is only looked in when you are on top +这一袋东西只会在 988 00:51:50,174 --> 00:51:54,110 the of a navigation controller stack. +navigationController 堆中最上面展示 989 00:51:54,112 --> 00:51:57,279 All right, so let's see if that works. +好的，让我们看看是否有用 990 00:52:00,585 --> 00:52:02,384 All right, here we go. Let's try angry, +运行一下，我们来点击 angry 991 00:52:02,386 --> 00:52:07,022 there it is, angry, happy, worried, mischievous. Okay, +这里的标题有 angry, happy, worried, mischievous 992 00:52:07,024 --> 00:52:10,626 and let's make sure that it's working on iPhone. +让我确认在 iPhone 中是否运行良好 993 00:52:19,237 --> 00:52:21,837 All right, let's go back here. Angry. Yes. +好的，让我们回到这里，angry 994 00:52:21,839 --> 00:52:23,539 Look he even got the title right. Happy. +看起来我们正确的设置了标题 995 00:52:23,541 --> 00:52:27,743 That's definitely happy. Worried. Okay? +happy，这确确实实是 happy，worried 996 00:52:27,745 --> 00:52:32,381 All right, everyone got that? So this is how we can build +好的，大家都明白了吗？这就是怎样 997 00:52:32,383 --> 00:52:36,085 these nice apps that work on both platforms, okay? They - +做一个 app 可以适配各个平台，对吗？ + 998 00:52:36,087 --> 00:52:38,254 work in split views. They work in navigation controllers. +这是在 split view 里的，它们都在 navigationController 里面 999 00:52:38,256 --> 00:52:41,157 Now if you were building an iPhone only app, you could do +如果你只是做一个 iPhone 的 app 1000 00:52:41,159 --> 00:52:44,460 this exact same thing but you wouldn't need the split view. +你可以不用 splitView 就完成同样的事情 1001 00:52:44,462 --> 00:52:45,327