How to test if a point is in a view

问题:

I have a UIImageView and I have a CGPoint on the screen. I want to be able to test that point to see if it is in the UIImageView. What would be the best way to do this?

回答1:

CGPoint is no good with a reference point. If your point is in window's coordinates then you can get it using

CGPoint locationInView = [imageView convertPoint:point fromView:imageView.window];
if ( CGRectContainsPoint(imageView.bounds, locationInView) ) {
    // Point lies inside the bounds.
}

You may also call pointInside:withEvent: method

if ( [imageView pointInside:locationInView withEvent:nil] ) {
    // Point lies inside the bounds
}

回答2:

Tested in Swift 4

view.frame.contains(point)

回答3:

if(CGRectContainsPoint([myView frame], point))

where point is your CGPoint and myView is your UIImageView

回答4:

I'll assume you have a full-screen window (pretty reasonable, I think). Then you can transform the point from the window's coordinate space to the UIImageView's using:

CGPoint point = ...
UIWindow window = ...
UIImageView imageView = ...
CGPoint transformedPoint = [window convertPoint:point toView:imageView];

Then, you can test if the point is in the image view's frame as follows:

if(CGRectContainsPoint(imageView.frame, transformedPoint))
{
    // do something interesting....
}

回答5:

In Swift 3

let isPointInFrame = UIScreen.main.bounds.contains(newLocation)