Is there a way to pause a CABasicAnimation?

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I have a basic spinning animation of the iPhone. Is there any way that I can "pause" the animation so that the position of the view will be maintained? I guess one way of doing this would be to cause the animation to "complete" instead of calling "remove" on it, how would I do that?

CABasicAnimation* rotationAnimation;
rotationAnimation = [CABasicAnimation animationWithKeyPath:@"transform.rotation.z"];
rotationAnimation.toValue = [NSNumber numberWithFloat: M_PI * 2];
rotationAnimation.duration = 100;
rotationAnimation.cumulative = YES;
rotationAnimation.repeatCount = HUGE_VALF;
rotationAnimation.removedOnCompletion = NO;
rotationAnimation.fillMode = kCAFillModeForwards;
[myView.layer addAnimation:rotationAnimation forKey:@"rotationAnimation"];
6 Answers

Set the current state of your view's layer to match the state of the presentationLayer, then remove the animation:

CALayer *pLayer = [myView.layer presentationLayer];
myView.layer.transform = pLayer.transform;
[myView.layer removeAnimationForKey:@"rotationAnimation"];

Credit to @Vladimir and @Supratik-Majumdar

Swift 5.1 as a CALayer extension

    extension CALayer
    {
        func pauseAnimation() {
            if isPaused() == false {
                let pausedTime = convertTime(CACurrentMediaTime(), from: nil)
                speed = 0.0
                timeOffset = pausedTime
            }
        }

        func resumeAnimation() {
            if isPaused() {
                let pausedTime = timeOffset
                speed = 1.0
                timeOffset = 0.0
                beginTime = 0.0
                let timeSincePause = convertTime(CACurrentMediaTime(), from: nil) - pausedTime
                beginTime = timeSincePause
            }
        }

        func isPaused() -> Bool {
            return speed == 0
        }
    }
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