Question

If I have a UIImageView and want to know if a user has tapped the image. In touchesBegan, I do the following but always end up in the first conditional. The window is in portrait mode and the image is at the bottom. I can tap in the upper right of the window and still go into the first condition, which seems very incorrect.

- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInView:touch.view];

if(CGRectContainsPoint(myimage.frame, location) == 0){
//always end up here
}
else
{ //user didn't tap inside image}

and the values are:

location: x=303,y=102
frame: origin=(x=210,y=394) size=(width=90, height=15)

Any suggestions?

Answer 1

First, you get the touch with:

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

Next, you want to be checking for the locationInView relative to your image view.

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

Next, CGRectContainsPoint returns a boolean, so comparing it to 0 is very odd. It should be:

if ( CGRectContainsPoint( myimage.frame, location ) ) {
   // inside
} else {
   // outside
}

But if self is not myimage then the myimage view may be getting the touch instead of you – its not clear from your question what object self is it is is not a subclass of the UIImageView in question.