iOS-点击图片放大，再次点击返回原视图

@interface CommunityTableViewCell ()
{
     CGRect oldframe ;
}
@end

//开始touch
-(void)touchesBegan:(NSSet<UITouch *> *)touches withEvent:(UIEvent *)event{
    UITouch *touch = [touches anyObject];
    //如果touch的是图片
    if ([touch.view isMemberOfClass:[UIImageView class]]) {
        UIImageView *selectView =  (UIImageView *)touch.view;
        [self showImage:selectView];
    }    
}
//图片放大
-(void)showImage:(UIImageView *)avatarImageView{
   
    UIImage *image=avatarImageView.image;
    UIWindow *window=[UIApplication sharedApplication].keyWindow;
    UIView *backgroundView=[[UIView alloc]initWithFrame:[UIScreen mainScreen].bounds] ;
    
    oldframe=[avatarImageView convertRect:avatarImageView.bounds toView:window];
    
    backgroundView.backgroundColor=[UIColor blackColor];
    backgroundView.alpha=0;
    
    UIImageView *imageView=[[UIImageView alloc]initWithFrame:oldframe];
    imageView.image=image;
    imageView.tag=1;
    
    [backgroundView addSubview:imageView];
    [window addSubview:backgroundView];
    
    UITapGestureRecognizer *tap=[[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(hideImage:)];
    [backgroundView addGestureRecognizer: tap];
    
    [UIView animateWithDuration:0.3 animations:^{
        imageView.frame=CGRectMake(0,(YiChe_Size.size.height-image.size.height*YiChe_Size.size.width/image.size.width)/2,YiChe_Size.size.width, image.size.height*YiChe_Size.size.width/image.size.width);
        backgroundView.alpha=1;
    } completion:^(BOOL finished) {
        
    }];
}
//再次点击隐藏图片
-(void)hideImage:(UITapGestureRecognizer*)tap{
    UIView *backgroundView=tap.view;
    UIImageView *imageView=(UIImageView*)[tap.view viewWithTag:1];
    [UIView animateWithDuration:0.3 animations:^{
        imageView.frame=oldframe;
        backgroundView.alpha=0;
    } completion:^(BOOL finished) {
        [backgroundView removeFromSuperview];
    }];
}