iOS开发 播放Gif图，且只播放一次

市面上播放GIF的控件很多，比较了几款后最后决定使用YYAnimatedImageView，简单易懂，且不会像FLAnimatedImageView导致内存暴涨
直接上代码

  YYAnimatedImageView *gifImageView = [[YYAnimatedImageView alloc] initWithFrame:CGRectMake(0, kNavigationBarHeight + 40,scaleFactorForWidth(400), scaleFactorForWidth(302))];
  YYImage *img = [YYImage imageNamed:@"snore_gif.gif"];
  gifImageView.image = img;
  [self addSubview:gifImageView];

此时有个需求，GIF只需播放一遍

//1.获取GIF图的图片总数
NSArray *imagesArray = [self getImageFromGifResource:@"snore_gif"];
//2.监听gif
    [RACObserve(gifImageView, currentAnimatedImageIndex) subscribeNext:^(id _Nullable x) {
        if ([x integerValue] == imagesArray.count - 1) {
            [gifImageView stopAnimating];
        }
    }];
//这样就会只播放一遍，紫萼停留在最后一帧

获取GIF图片总数

- (NSArray <UIImage *>*)getImageFromGifResource:(NSString *)resource {
    NSMutableArray *imageArray = [NSMutableArray array];
    
    // 获取gif url
    NSURL *url = [[NSBundle mainBundle] URLForResource:resource withExtension:@"gif"];
    // 转换为图片源
    CGImageSourceRef gifImageSourceRef = CGImageSourceCreateWithURL((CFURLRef)url, nil);
    // 获取图片个数
    size_t framesCount = CGImageSourceGetCount(gifImageSourceRef);
    for (size_t index = 0; index < framesCount; index ++) {
        CGImageRef imageRef = CGImageSourceCreateImageAtIndex(gifImageSourceRef, index , nil);
        
        UIImage *image = [UIImage imageWithCGImage:imageRef];
        [imageArray addObject:image];
        
        CFRelease(imageRef);
    }
    
    return imageArray;
}