xcode - 如何检查与 UIImageView 的触摸接近度？

Question

有谁知道我将如何在 Xcode 中检查与 UIImageView 的触摸接近度？我正在尝试检查触摸是否在围绕屏幕移动的 UIImageView 的 25 像素内。任何帮助，将不胜感激。谢谢你。

Answer 1

首先，您可以接触到：

UITouch *touch = [[event allTouches] anyObject];

接下来，您要检查相对于图像视图的 locationInView。

CGPoint touchlocation = [touch locationInView:self]; // or possibly myimage instead of self.

接下来，CGRectContainsPoint 返回一个布尔值。它应该是：

if ( CGRectContainsPoint( imgView.frame, touchlocation ) ) {
   // inside imgView
} else {
   // outside imgView Now we will found out is it within proximityImgViewRect
   CGRect *proximityImgViewRect = CGRectMake( imgView.frame.origin.x-25,imgView.frame.origin.y - 25, imgView.frame.size.width+50,imgView.frame.size.height+50); 
   if ( CGRectContainsPoint( proximityImgViewRect.frame, touchlocation ) ) {
     // inside proximityImgViewRect
   } else {
    //outside proximityImgViewRect
   }
}