Basic hit test.

[ozzie]

Can anyone think why this isn't working? It's really simple but doesn't seem to work. The key is supposed to disappear when it touches the character which is animated by a simple UIView animation and it's called by:

[UIView setAnimationDidStopSelector:@selector(FinishedWalking)];

The problem is it seems to disappear almost randomly after you walk, even if you haven't collided with it. Heres the collision code:

-(void)FinishedWalking{
	if(CGRectIntersectsRect(Key.frame, Character.frame)){
		Key.hidden = YES;
		KeyObtained = YES;
	}
}

The key and Character and both inside the same UIView. Any help would be greatly appreciated.

Cheers,
Ozzie

[smasher]

The code looks OK. Remember that it's checking rectangles, so if the rectangles overlap you'll have a collision, even if the visible parts of the images are not touching.

Also, the .frame property is not accurate when using a UIView animation. It only seems to tell you where the endpoint of the animation will be, not the "real" location of the image on the screen. You're only checking for collisions at the end of the animation though, so maybe your animations are short and that's OK?

If they had different parents you'd have to convert one of the rectangles; but you said "The key and Character and both inside the same UIView" -- do they both have the same direct parent? They're both children of the same view? Then that's OK too.

If it's still not working, put these logs inside your if statement and post the result for one of the "wrong" pickups.

NSLog(@"Character: %f,%f  %f,%f", Character.frame.origin.x, Character.frame.origin.y, Character.frame.size.width, Character.frame.size.height);
NSLog(@"Key: %f,%f  %f,%f", , Key.frame.origin.x, Key.frame.origin.y, Key.frame.size.width, Key.frame.size.height);

[BostonMerlin]

be careful using @selector(animationDidStop:finished:context. My latest app was rejected for using that specific method.

[smasher]

That sounds like some kind of false positive; or were you calling the system method called animationDidStop:finished:context: ?

Using setAnimationDidStopSelector: is a perfectly valid and documented in the SDK. Maybe if you don't name your method animationDidStop:finished:context then you'll avoid the false positive.