Merge pull request IFTTT#1688 from ashavit/mask_animation

Swipe Animation

Author: lauraskelton

Example/Pods/Headers/Private/JazzHands/IFTTTMaskAnimation.h

@@ -22,6 +22,7 @@
 #import "IFTTTAnimatedPagingScrollViewController.h"
 
 #import "IFTTTAlphaAnimation.h"
+#import "IFTTTMaskAnimation.h"
 #import "IFTTTCornerRadiusAnimation.h"
 #import "IFTTTFrameAnimation.h"
 #import "IFTTTHideAnimation.h"

Example/Pods/Headers/Private/Masonry/ViewController+MASAdditions.h

@@ -0,0 +1,27 @@
+//
+//  IFTTTMaskAnimation.h
+//  JazzHands
+//
+//  Created by Amir Shavit on 7/26/15.
+//  Copyright (c) 2015 IFTTT Inc. All rights reserved.
+//
+
+#import "IFTTTAnimation.h"
+
+typedef NS_ENUM(NSUInteger, IFTTTMaskSwipeDirection)
+{
+    IFTTTMaskSwipeFromTop,
+    IFTTTMaskSwipeFromLeft,
+    IFTTTMaskSwipeFromBottom,
+    IFTTTMaskSwipeFromRight
+};
+
+@interface IFTTTMaskAnimation : IFTTTAnimation <IFTTTAnimatable>
+
+- (instancetype)initWithView:(UIView *)view direction:(IFTTTMaskSwipeDirection)direction NS_DESIGNATED_INITIALIZER;
++ (instancetype)animationWithView:(UIView *)view direction:(IFTTTMaskSwipeDirection)direction;
+
+- (void)addKeyframeForTime:(CGFloat)time visibility:(CGFloat)percent;
+- (void)addKeyframeForTime:(CGFloat)time visibility:(CGFloat)percent withEasingFunction:(IFTTTEasingFunction)easingFunction;
+
+@end

Example/Pods/Headers/Public/JazzHands/IFTTTMaskAnimation.h

@@ -0,0 +1,92 @@
+//
+//  IFTTTMaskAnimation.m
+//  JazzHands
+//
+//  Created by Amir Shavit on 7/26/15.
+//  Copyright (c) 2015 IFTTT Inc. All rights reserved.
+//
+
+#import "IFTTTMaskAnimation.h"
+
+@interface IFTTTMaskAnimation ()
+
+@property (nonatomic, strong) UIView* maskedView;
+@property (nonatomic, assign) IFTTTMaskSwipeDirection direction;
+
+@end
+
+@implementation IFTTTMaskAnimation
+
+#pragma mark - Init
+
+- (instancetype)initWithView:(UIView *)view direction:(IFTTTMaskSwipeDirection)direction
+{
+    if ((self = [super init])) {
+        _maskedView = view;
+        _direction = direction;
+    }
+    return self;
+}
+
++ (instancetype)animationWithView:(UIView *)view direction:(IFTTTMaskSwipeDirection)direction
+{
+    return [[self alloc] initWithView:view direction:direction];
+}
+
+#pragma mark - Public Methods
+
+- (void)addKeyframeForTime:(CGFloat)time visibility:(CGFloat)percent
+{
+    [self addKeyframeForTime:time value:@(percent)];
+}
+
+- (void)addKeyframeForTime:(CGFloat)time visibility:(CGFloat)percent withEasingFunction:(IFTTTEasingFunction)easingFunction
+{
+    [self addKeyframeForTime:time value:@(percent) withEasingFunction:easingFunction];
+}
+
+#pragma mark - IFTTTAnimatable Protocol
+
+- (void)animate:(CGFloat)time
+{
+    if (!self.hasKeyframes) return;
+    CGFloat visibilityPercent = ((NSNumber *)[self valueAtTime:time]).floatValue;
+    
+    CGRect maskedRect = self.maskedView.bounds;
+    switch (self.direction)
+    {
+        case IFTTTMaskSwipeFromTop:
+        {
+            maskedRect.size.height *= visibilityPercent;
+            break;
+        }
+        case IFTTTMaskSwipeFromLeft:
+        {
+            maskedRect.size.width *= visibilityPercent;
+            break;
+        }
+        case IFTTTMaskSwipeFromBottom:
+        {
+            maskedRect.size.height *= visibilityPercent;
+            maskedRect.origin.y = CGRectGetMaxY(self.maskedView.bounds) - maskedRect.size.height;
+            break;
+        }
+        case IFTTTMaskSwipeFromRight:
+        {
+            maskedRect.size.width *= visibilityPercent;
+            maskedRect.origin.x = CGRectGetMaxX(self.maskedView.bounds) - maskedRect.size.width;
+            break;
+        }
+            
+        default:
+            break;
+    }
+
+    UIBezierPath* maskPath = [UIBezierPath bezierPathWithRect:maskedRect];
+
+    CAShapeLayer* maskLayer = [CAShapeLayer new];
+    maskLayer.path = maskPath.CGPath;
+    self.maskedView.layer.mask = maskLayer;
+}
+
+@end