ios - CGAffineTransformRotate 之后 CGRectIntersection 不起作用

Question

首先，我几乎检查了互联网上的所有地方，但没有得到有关此主题的任何解决方案。

在我的例子中，我在一个 super View 中有多个 UIView 对象，或者你可以说我在 Canvas 上绘制这个 View 。

1. 所有这些 View 都附加了平移手势，因此它们可以移动到其 super View 的任何位置。

2. 其中一些 View 可以使用旋转手势或 CGAffineTransformRotate 进行旋转。

   1. 只要任何 View 位于主视图之外，它就会被删除。

现在以下是我的代码。

@IBOutlet weak var mainView: UIView!

  var newViewToAdd = UIView()
  newViewToAdd.layer.masksToBounds = true
  var transForm = CGAffineTransformIdentity
  transForm = CGAffineTransformScale(transForm, 0.8, 1)
  transForm = CGAffineTransformRotate(transForm, CGFloat(M_PI_4)) //Making the transformation
  newViewToAdd.layer.shouldRasterize = true //Making the view edges smooth after applying transforamtion
  newViewToAdd.transform = transForm
  self.mainView.addSubview(newViewToAdd) //Adding the view to the main view.

现在，如果手势识别器位于自定义 UIView 类中 -

var lastLocation: CGPoint = CGPointMake(0, 0)

 override func touchesBegan(touches: Set<UITouch>, withEvent event: UIEvent?) {
    self.superview?.bringSubviewToFront(self)
    lastLocation = self.center //Getting the last center point of the view on first touch.
  }

  func detectPan(recognizer: UIPanGestureRecognizer){
    let translation = recognizer.translationInView(self.superview!) //Making the translation
    self.center = CGPointMake(lastLocation.x + translation.x, lastLocation.y + translation.y) //Updating the center point.
    switch(recognizer.state){
    case .Began:
             break
    case .Changed:
        //MARK: - Checking The view is outside of the Superview or not
        if (!CGRectEqualToRect(CGRectIntersection(self.superview!.bounds, self.frame), self.frame)) //if its true then view background color will be changed else background will be replaced.
        {
            self.backgroundColor = outsideTheViewColor
            var imageViewBin : UIImageView
            imageViewBin  = UIImageView(frame:CGRectMake(0, 0, 20, 25));
            imageViewBin.image = UIImage(named:"GarbageBin")
            imageViewBin.center = CGPointMake(self.frame.width/2, self.frame.height/2)
            addSubview(imageViewBin)

        }else{
            for subViews in self.subviews{
                if subViews.isKindOfClass(UIImageView){
                    subViews.removeFromSuperview()
                }
                self.backgroundColor = deSelectedColorForTable
            }
        }
    case .Ended:
        if (!CGRectEqualToRect(CGRectIntersection(self.superview!.bounds, self.frame), self.frame)) //If its true then the view will be deleted.
        {
            self.removeFromSuperview()
        }

    default: break
    }
}

主要问题是，如果 View 未旋转或变换，则 .Changed/.Ended 情况下的所有“CGRectIntersection”都按预期正常工作，但如果 View 旋转或变换，则“CGRectIntersection”始终变为 true 即使该 View 位于“mainView”内部，并将其从主视图/ super View 中删除。

请帮助解决我的错误。

提前致谢。

Answer 1

View 的框架在应用变换后得到更新。以下代码确保它在其父 View 范围内。

if (CGRectContainsRect(self.superview!.bounds, self.frame))
{
    //view is inside of the Superview
}
else
{
    //view is outside of the Superview
}