added variadic methods for creating keyframes

Author: jeremyflores

JazzHandsDemo/JazzHandsDemo/IFTTTJazzHandsViewController.m

@@ -10,7 +10,7 @@
 
 #define NUMBER_OF_PAGES 4
 
-#define timeForPage(page) (self.view.frame.size.width * (page - 1))
+#define timeForPage(page) (NSInteger)(self.view.frame.size.width * (page - 1))
 #define xForPage(page) timeForPage(page)
 
 @interface IFTTTJazzHandsViewController ()

src/IFTTTAnimation.h

@@ -18,6 +18,8 @@
 - (id)initWithView:(UIView *)view;
 
 - (void)animate:(NSInteger)time;
+
+- (void)addKeyFrames:(NSArray *)keyFrames;
 - (void)addKeyFrame:(IFTTTAnimationKeyFrame *)keyFrame;
 
 - (IFTTTAnimationFrame *)animationFrameForTime:(NSInteger)time;

src/IFTTTAnimation.m

@@ -43,6 +43,13 @@ - (id)initWithView:(UIView *)view
     return self;
 }
 
+- (void)addKeyFrames:(NSArray *)keyFrames
+{
+    for (IFTTTAnimationKeyFrame *keyFrame in keyFrames) {
+        [self addKeyFrame:keyFrame];
+    }
+}
+
 - (void)addKeyFrame:(IFTTTAnimationKeyFrame *)keyFrame
 {
     if (self.keyFrames.count == 0) {

src/IFTTTAnimationKeyFrame.h

@@ -10,6 +10,19 @@
 
 @interface IFTTTAnimationKeyFrame : IFTTTAnimationFrame
 
+// These variadic methods require arguments to be of the form
+//
+//      n, time_1, value_1, time_2, value_2, ..., time_n, value_n,
+//
+// where n is the number of time-value pairs. That is, the number of pairs must be the
+// first argument, then the method will take care of unpacking the rest of the times and
+// values into keyframe objects.
+//
++ (NSArray *)keyFramesWithTimesAndAlphas:(NSInteger)pairCount,...;
++ (NSArray *)keyFramesWithTimesAndFrames:(NSInteger)pairCount,...;
++ (NSArray *)keyFramesWithTimesAndHiddens:(NSInteger)pairCount,...;
++ (NSArray *)keyFramesWithTimesAndColors:(NSInteger)pairCount,...;
+
 + (instancetype)keyFrameWithTime:(NSInteger)time andAlpha:(CGFloat)alpha;
 + (instancetype)keyFrameWithTime:(NSInteger)time andFrame:(CGRect)frame;
 + (instancetype)keyFrameWithTime:(NSInteger)time andHidden:(BOOL)hidden;

src/IFTTTAnimationKeyFrame.m

@@ -10,6 +10,114 @@
 
 @implementation IFTTTAnimationKeyFrame
 
++ (NSArray *)keyFramesWithTimesAndAlphas:(NSInteger)pairCount,...
+{
+    va_list argumentList;
+    NSInteger time;
+    CGFloat alpha;
+    if (pairCount > 0) {
+        NSMutableArray *keyFrames = [NSMutableArray arrayWithCapacity:pairCount];
+        
+        va_start(argumentList, pairCount);
+
+        for (int i=0; i<pairCount; i++) {
+            time = va_arg(argumentList, NSInteger);
+            alpha = va_arg(argumentList, double);   // use double to suppress a va_arg conversion warning
+            IFTTTAnimationKeyFrame *keyFrame = [IFTTTAnimationKeyFrame keyFrameWithTime: time
+                                                                               andAlpha: alpha];
+            [keyFrames addObject:keyFrame];
+        }
+
+        va_end(argumentList);
+
+        return [NSArray arrayWithArray:keyFrames];
+    }
+    else {
+        return nil;
+    }
+}
+
++ (NSArray *)keyFramesWithTimesAndFrames:(NSInteger)pairCount,...
+{
+    va_list argumentList;
+    NSInteger time;
+    CGRect frame;
+    if (pairCount > 0) {
+        NSMutableArray *keyFrames = [NSMutableArray arrayWithCapacity:pairCount];
+        
+        va_start(argumentList, pairCount);
+        
+        for (int i=0; i<pairCount; i++) {
+            time = va_arg(argumentList, NSInteger);
+            frame = va_arg(argumentList, CGRect);
+            IFTTTAnimationKeyFrame *keyFrame = [IFTTTAnimationKeyFrame keyFrameWithTime: time
+                                                                               andFrame: frame];
+            [keyFrames addObject:keyFrame];
+        }
+        
+        va_end(argumentList);
+        
+        return [NSArray arrayWithArray:keyFrames];
+    }
+    else {
+        return nil;
+    }
+}
+
++ (NSArray *)keyFramesWithTimesAndHiddens:(NSInteger)pairCount,...
+{
+    va_list argumentList;
+    NSInteger time;
+    BOOL hidden;
+    if (pairCount > 0) {
+        NSMutableArray *keyFrames = [NSMutableArray arrayWithCapacity:pairCount];
+        
+        va_start(argumentList, pairCount);
+        
+        for (int i=0; i<pairCount; i++) {
+            time = va_arg(argumentList, NSInteger);
+            hidden = va_arg(argumentList, int); // use int to suppress a va_arg conversion warning
+            IFTTTAnimationKeyFrame *keyFrame = [IFTTTAnimationKeyFrame keyFrameWithTime: time
+                                                                              andHidden: hidden];
+            [keyFrames addObject:keyFrame];
+        }
+        
+        va_end(argumentList);
+        
+        return [NSArray arrayWithArray:keyFrames];
+    }
+    else {
+        return nil;
+    }
+}
+
++ (NSArray *)keyFramesWithTimesAndColors:(NSInteger)pairCount,...
+{
+    va_list argumentList;
+    NSInteger time;
+    UIColor *color;
+    if (pairCount > 0) {
+        NSMutableArray *keyFrames = [NSMutableArray arrayWithCapacity:pairCount];
+        
+        va_start(argumentList, pairCount);
+        
+        for (int i=0; i<pairCount; i++) {
+            time = va_arg(argumentList, NSInteger);
+            color = va_arg(argumentList, id);
+            IFTTTAnimationKeyFrame *keyFrame = [IFTTTAnimationKeyFrame keyFrameWithTime: time
+                                                                               andColor: color];
+            [keyFrames addObject:keyFrame];
+        }
+        
+        va_end(argumentList);
+        
+        return [NSArray arrayWithArray:keyFrames];
+    }
+    else {
+        return nil;
+    }
+}
+
 + (instancetype)keyFrameWithTime:(NSInteger)time andAlpha:(CGFloat)alpha
 {
     IFTTTAnimationKeyFrame *keyFrame = [[[self class] alloc] initWithTime: time