How to specify selector when CAKeyframeAnimation is finished?
cakeyframeanimation, catransaction, core-animation, iphone
Solution
CAKeyframeAnimation is a subclass of CAAnimation. There is a `delegate` property in CAAnimation. The delegate can implement the `-animationDidStop:finished:` method. The rest should be easy.
Problem
I'm using a CAKeyframeAnimation to animate a view along a CGPath. When the animation is done, I'd like to be able to call some other method to perform another action. Is there a good way to do this? I've looked at using UIView's setAnimationDidStopSelector:, however from the docs this looks like it only applies when used within a UIView animation block (beginAnimations and commitAnimations). I also gave it a try just in case, but it doesn't seem to work. Here's some sample code (this is within a custom UIView sub-class method): ``` // These have no effect since they're not in a UIView Animation Block [UIView setAnimationDelegate:self]; [UIView setAnimationDidStopSelector:@selector(animationDidStop:finished:context:)]; // Set up path movement CAKeyframeAnimation *pathAnimation = [CAKeyframeAnimation animationWithKeyPath:@"path"]; pathAnimation.calculationMode = kCAAnimationPaced; pathAnimation.fillMode = kCAFillModeForwards; pathAnimation.removedOnCompletion = NO; pathAnimation.duration = 1.0f; CGMutablePathRef path = CGPathCreateMutable(); CGPathMoveToPoint(path, NULL, self.center.x, self.center.y); // add all points to the path for (NSValue* value in myPoints) { CGPoint nextPoint = [value CGPointValue]; CGPathAddLineToPoint(path, NULL, nextPoint.x, nextPoint.y); } pathAnimation.path = path; CGPathRelease(path); [self.layer addAnimation:pathAnimation forKey:@"pathAnimation"]; ``` A workaround I was considering that should work, but doesn't seem like the best way, is to use NSObject's performSelector:withObject:afterDelay:. As long as I set the delay equal to the duration of the animation, then it should be fine. Is there a better way? Thanks!