给图片添加手势监听器(点击图片放大)

//添加手势
            UITapGestureRecognizer *recognizer = [[UITapGestureRecognizer alloc] init];
            [recognizer addTarget:self action:@selector(tapPhoto:)];
            [photoView addGestureRecognizer:recognizer];

 *  监听图片的点击
 */
- (void)tapPhoto:(UITapGestureRecognizer *)recognizer
{
    //1.添加一个遮盖
    UIView *cover = [[UIView alloc] init];
    cover.frame = [UIScreen mainScreen].bounds;
    cover.backgroundColor = [UIColor blackColor];
    [[UIApplication sharedApplication].keyWindow addSubview:cover];
    
    //2.添加图片到遮盖上
    StatusPhotoView *photoView = (StatusPhotoView *)recognizer.view;
    UIImageView *imageView = [[UIImageView alloc] init];
    imageView.image = photoView.image;
    //将photoView.frame从self坐标转为cover坐标系
    imageView.frame = [cover convertRect:photoView.frame fromView:self];
    [cover addSubview:imageView];
    
    //3.放大
    [UIView animateWithDuration:0.25 animations:^{
        CGRect frame = imageView.frame;
        frame.size.width = cover.frame.size.width;
        frame.size.height = frame.size.width * (imageView.image.size.height / imageView.image.size.width);
        frame.origin.x = 0;
        frame.origin.y = (cover.frame.size.height - frame.size.height) * 0.5;
        imageView.frame = frame;
    }];
}