YYKit---Image gif

帧动画 YYFrameImage 继承UIImage 

1.- (nullable instancetype)initWithImagePaths:(NSArray*)paths／／图片路径

oneFrameDuration:(NSTimeInterval)oneFrameDuration／／每张图片播放时间

loopCount:(NSUInteger)loopCount;／／循环次数，0代表，不限次数

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2.- (nullable instancetype)initWithImagePaths:(NSArray*)paths                            frameDurations:(NSArray*)frameDurations／／@[ @0.1,@0.2,@0.3];

loopCount:(NSUInteger)loopCount;

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也可以用NSData创建

3.- (nullable instancetype)initWithImageDataArray:(NSArray*)dataArray

oneFrameDuration:(NSTimeInterval)oneFrameDuration

loopCount:(NSUInteger)loopCount;

4.- (nullable instancetype)initWithImageDataArray:(NSArray*)dataArray

frameDurations:(NSArray *)frameDurations

loopCount:(NSUInteger)loopCount;

ps.只支持png and jpeg

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YYImage 继承UIImage

YYImage *image = [YYImage imageNamed:name];／／这样就可以加载本地的图片和GIF ，webP的动态图

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YYSpriteSheetImage 继承UIImage 

用于截取图片，然后播放动态图。代码如下：

CGSize size = CGSizeMake(sheet.size.width / 8, sheet.size.height / 12);／／12 行8列的sheet(UIImage)

for (int j = 0; j < 12; j++) {

for (int i = 0; i < 8; i++) {

CGRect rect;

rect.size = size;

rect.origin.x = sheet.size.width / 8 * i;

rect.origin.y = sheet.size.height / 12 * j;

[contentRects addObject:[NSValue valueWithCGRect:rect]];／／NSValue 类型的

[durations addObject:@(1 / 60.0)];／／NSNumber 类型

}

}

YYSpriteSheetImage *sprite;

sprite = [[YYSpriteSheetImage alloc] initWithSpriteSheetImage:sheet contentRects:contentRects frameDurations:durations loopCount:0];

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YYAnimatedImageView 继承UIImageView

- (BOOL)isAnimating; 是否在动画

- (void)startAnimating;开始动画

- (void)stopAnimating;停止动画 ／／都是UIImageView 的方法

加载网络图片和SDWebImage 差不多

YYKit 有一个UIImageView 和UIButton的分类 可以加载网络图片，png，等等

- (void)setImageWithURL:(nullable NSURL *)imageURL placeholder:(nullable UIImage *)placeholder;

想实现点击播放，点击停止，是需要给YYAnimatedImageView
 添加tap手势。判断是否正在动画，来决定开始还是停止动画。

实现左滑右滑，前进后退。YYImage等都遵守协议.

+ (void)addPanControlToAnimatedImageView:(YYAnimatedImageView *)view {  

if (!view) return;  ／／

  view.userInteractionEnabled = YES;

  __weak typeof(view) _view = view;  

__block BOOL previousIsPlaying;    ／／记录滑动前是否动画

    UIPanGestureRecognizer *pan = [[UIPanGestureRecognizer alloc] initWithActionBlock:^(id sender) {      

UIImage*image = (id)_view.image;

if (![image conformsToProtocol:@protocol(YYAnimatedImage)]) return;／／image 是否遵守协议

UIPanGestureRecognizer *gesture = sender;

CGPoint p = [gesture locationInView:gesture.view];

CGFloat progress = p.x / gesture.view.width;

if (gesture.state == UIGestureRecognizerStateBegan) {／／手势开始时，记录当前是否动画，并

previousIsPlaying = [_view isAnimating];                                停止动画。把当前在的index赋值给

[_view stopAnimating];                                                              View

_view.currentAnimatedImageIndex = image.animatedImageFrameCount * progress;

}

else if (gesture.state == UIGestureRecognizerStateEnded ||gesture.state == UIGestureRecognizerStateCancelled) {／／手势结束时，恢复原先的状态

if (previousIsPlaying) [_view startAnimating];

} else {／／移动的时候，把当前的index服给View

_view.currentAnimatedImageIndex = image.animatedImageFrameCount * progress;

}

}];

[view addGestureRecognizer:pan];

}