//要引入ImageIO庫(kù)
#import <ImageIO/ImageIO.h>

//解析gif文件數(shù)據(jù)的方法 block中會(huì)將解析的數(shù)據(jù)傳遞出來(lái)
-(void)getGifImageWithUrk:(NSURL *)url
    returnData:(void(^)(NSArray<UIImage *> * imageArray,
        NSArray<NSNumber *>*timeArray,
        CGFloat totalTime,
        NSArray<NSNumber *>* widths,
        NSArray<NSNumber *>* heights))dataBlock{
 //通過(guò)文件的url來(lái)將gif文件讀取為圖片數(shù)據(jù)引用
 CGImageSourceRef source = CGImageSourceCreateWithURL((CFURLRef)url, NULL);
 //獲取gif文件中圖片的個(gè)數(shù)
 size_t count = CGImageSourceGetCount(source);
 //定義一個(gè)變量記錄gif播放一輪的時(shí)間
 float allTime=0;
 //存放所有圖片
 NSMutableArray * imageArray = [[NSMutableArray alloc]init];
 //存放每一幀播放的時(shí)間
 NSMutableArray * timeArray = [[NSMutableArray alloc]init];
 //存放每張圖片的寬度 （一般在一個(gè)gif文件中，所有圖片尺寸都會(huì)一樣）
 NSMutableArray * widthArray = [[NSMutableArray alloc]init];
 //存放每張圖片的高度
 NSMutableArray * heightArray = [[NSMutableArray alloc]init];
 //遍歷
 for (size_t i=0; i<count; i++) {
  CGImageRef image = CGImageSourceCreateImageAtIndex(source, i, NULL);
  [imageArray addObject:(__bridge UIImage *)(image)];
  CGImageRelease(image);
  //獲取圖片信息
  NSDictionary * info = (__bridge NSDictionary*)CGImageSourceCopyPropertiesAtIndex(source, i, NULL);
  CGFloat width = [[info objectForKey:(__bridge NSString *)kCGImagePropertyPixelWidth] floatValue];
  CGFloat height = [[info objectForKey:(__bridge NSString *)kCGImagePropertyPixelHeight] floatValue];
  [widthArray addObject:[NSNumber numberWithFloat:width]];
  [heightArray addObject:[NSNumber numberWithFloat:height]];
  NSDictionary * timeDic = [info objectForKey:(__bridge NSString *)kCGImagePropertyGIFDictionary];
  CGFloat time = [[timeDic objectForKey:(__bridge NSString *)kCGImagePropertyGIFDelayTime]floatValue];
  allTime+=time;
  [timeArray addObject:[NSNumber numberWithFloat:time]];
  CFRelease(info);
 }
 CFRelease(source);
 dataBlock(imageArray,timeArray,allTime,widthArray,heightArray);
}

-(void)yh_setImage:(NSURL *)imageUrl{
  __weak id __self = self;
  [self getGifImageWithUrk:imageUrl returnData:^(NSArray<UIImage *> *imageArray, NSArray<NSNumber *> *timeArray, CGFloat totalTime, NSArray<NSNumber *> *widths, NSArray<NSNumber *> *heights) {
   //添加幀動(dòng)畫(huà)
   CAKeyframeAnimation *animation = [CAKeyframeAnimation animationWithKeyPath:@"contents"];
   NSMutableArray * times = [[NSMutableArray alloc]init];
   float currentTime = 0;
   //設(shè)置每一幀的時(shí)間占比
   for (int i=0; i<imageArray.count; i++) {
    [times addObject:[NSNumber numberWithFloat:currentTime/totalTime]];
    currentTime+=[timeArray[i] floatValue];
   }
   [animation setKeyTimes:times];
   [animation setValues:imageArray];
   [animation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]];
   //設(shè)置循環(huán)
   animation.repeatCount= MAXFLOAT;
   //設(shè)置播放總時(shí)長(zhǎng)
   animation.duration = totalTime;
   //Layer層添加
   [[(UIImageView *)__self layer]addAnimation:animation forKey:@"gifAnimation"];
  }];
}

 UIImageView * imageView = [[UIImageView alloc]initWithFrame:CGRectMake(0,0 , 320, 200)];
 NSURL * url = [[NSURL alloc]initFileURLWithPath:[[NSBundle mainBundle] pathForResource:imageName ofType:nil]];
 [imageView yh_setImage:url];
 [self.view addSubview:imageView];

 //讀取gif數(shù)據(jù)
   NSData *gifData = [NSData dataWithContentsOfURL:imageUrl];
  UIWebView *webView = [[UIWebView alloc] initWithFrame:CGRectMake(0, 0, self.frame.size.width, self.frame.size.height)];
  //取消回彈效果
  webView.scrollView.bounces=NO;
  webView.backgroundColor = [UIColor clearColor];
  //設(shè)置縮放模式
  webView.scalesPageToFit = YES;
  //用webView加載數(shù)據(jù)
  [webView loadData:gifData MIMEType:@"image/gif" textEncodingName:nil baseURL:nil];