ios - 如何在 iOS 中释放或隐藏 UIImageView？隐藏不起作用

Question

我的目的是当我拖动一个对象时，一个小的UIImageView 显示，当触摸结束时，UIImageView 被释放。

- (IBAction)TLMove:(UIPanGestureRecognizer *)sender {

//add UIImage view to show the scaled dot
UIImageView *scaleUPView = [[UIImageView alloc] initWithFrame:CGRectMake(200, 30, 100, 100)] ;
scaleUPView.layer.zPosition = 300 ;
[scaleUPView setImage:self.OriginImage] ;
[self.view addSubview:scaleUPView] ;

self.TopLeftPoint.center = [sender locationInView:self.TopLeftPoint.superview] ;

targetTL = self.TopLeftPoint.center  ;

if (sender.state == UIGestureRecognizerStateEnded || sender.state == UIGestureRecognizerStateCancelled || sender.state == UIGestureRecognizerStateFailed)
{
    [scaleUPView setHidden:YES] ; // not working still shows
    [scaleUPView removeFromSuperview] ; //not working still shows
}
}

但这根本不起作用，我尝试了 scaleUPView.hidden =YES，仍然不起作用。 scaleUPView 将始终显示，我希望它在 ARC 模式下释放，我无法在启用引用计数时释放它。

Answer 1

你可以设置alpha = 0。你必须检查 if 语句中的 ure。

所以你的代码可能是这样的:

if (sender.state == UIGestureRecognizerStateEnded || sender.state == UIGestureRecognizerStateCancelled || sender.state == UIGestureRecognizerStateFailed)
{
    NSLog(@"inside if statement"); \\ 
    [scaleUPView setAlpha:0] ; 
    [scaleUPView removeFromSuperview] ; 
}

希望这对您有所帮助。