How to specify selector when CAKeyframeAnimation is finished?
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 开发者_开发问答better way? Thanks!
Or you can enclose your animation with:
[CATransaction begin];
[CATransaction setCompletionBlock:^{
/* what to do next */
}];
/* your animation code */
[CATransaction commit];
And set the completion block to handle what you need to do.
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.
Swift 3 syntax for this answer.
CATransaction.begin()
CATransaction.setCompletionBlock {
//Actions to be done after animation
}
//Animation Code
CATransaction.commit()
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