将UIView拖到另一个UIView的边界上（带有圆角）

Question

Basically I have a UIView which I need to drag along the bounds of another UIView (its superview) with a rounded corner. I have already implemented a draggable UIView . I'm having trouble finding a way to restrict the movement of the draggable UIView along the edges of its superview only.

Is there a way in which I can check if the UIView.center is on the superview's bounds?

Anyone have any ideas on how I can implement this? Thanks

Answer 1

You can use the CGRectContainsPoint to check whether an point is inside the view frame

-(void) methodThatWouldBeCalledWhenTheViewISDragged {

  CGPoint smallViewCenter = smallView.center;
    if ( CGRectContainsPoint(containerView.bounds, smallViewCenter) ) {
       // smallView is inside the ContainerView
    }
    else{   
       //smallView went outside
    }
  }

Answer 2

使用CGRectContainsPoint()进行检测。