我有两个占据整个屏幕的UIImageViews，这意味着它们的帧是:(0,0,320,480)。imageView2在imageView1之上。它们都使用CAShapeLayer应用了mask。我做了一个函数-(void)addMask:(CGRect)recttoView:(UIImageView*)imageView内容如下//Function-(void)addMask:(CGRect)recttoView:(UIImageView*)imageView{CAShapeLayer*shapeLayer=[[CAShapeLayeralloc]init];CGPathRefpath