How to implement animationdidstop - ios

Question

Good Evening!
I have a peace of code but it is not calling the animationdidstop method. I could not identify why it does not work. I`ve tried many solutions..
-(IBAction)MakeCircle:(id)sender{
// Add to parent layer
[self.view.layer addSublayer:circle];
// Configure animation
drawAnimation = [CABasicAnimation animationWithKeyPath:#"strokeEnd"];
drawAnimation.duration = 5.0;
drawAnimation.repeatCount = 1.0;
drawAnimation.fromValue = [NSNumber numberWithFloat:0.0f];
drawAnimation.toValue = [NSNumber numberWithFloat:1.0f];
drawAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear];
// Add the animation
[circle addAnimation:drawAnimation forKey:#"drawCircleAnimation"];}
-(void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag{
if(anim == [self.view.layer animationForKey:#"drawCircleAnimation"]){
Label.text = [NSString stringWithFormat:#"Loser"];
}
}
Thanks!!

Answer 1

You are not setting yourself as the delegate of the animation. Add this line before adding the animation:
drawAnimation.delegate = self;
Edit:
Oh. I know exactly what the problem is. The system copies your animation object when you submit the animation, so it won't be the same object in the completion routine. Try adding a unique key to the animation and checking that instead of checking to see if it's the same animation object you submitted.
e.g.:
drawAnimation = [CABasicAnimation animationWithKeyPath:#"strokeEnd"];
[drawAnimation setValue: #"mydrawCircleAnimation" forKey: #"animationKey"];
//The rest of your animation code...
Then in your animationDidStop:
-(void)animationDidStop:(CAAnimation *)anim finished:(BOOL)flag
{
if([anim valueForKey: #"animationKey"
isEqualToString: #"mydrawCircleAnimation"])
{
Label.text = [NSString stringWithFormat:#"Loser"];
}
}
Edit #2:
There is an even cleaner way to handle animation completion code. You can attach a block to your animations and then write a general animationDidStop:completion: method that looks for the block and invokes it if found. See my answer in this thread:
How to identify CAAnimation within the animationDidStop delegate?