How to reset ObjectAnimator to it's initial status?

NullPointerException picture NullPointerException · Dec 23, 2014 · Viewed 11.2k times · Source

I want to vibrate a view with scaleX and scaleY, and I am doing it with this code, but the problem is that sometimes the view is not correctly reset, and it shows with the scale applied...

I want that when the animation ends, the view must be seen with its original status always

this is the code:

                ObjectAnimator scaleX = ObjectAnimator.ofFloat(view, "scaleX", 1f, 0.9f);
                scaleX.setDuration(50);
                scaleX.setRepeatCount(5);
                scaleX.setRepeatMode(Animation.REVERSE);
                ObjectAnimator scaleY = ObjectAnimator.ofFloat(view, "scaleY", 1f, 0.9f);
                scaleY.setDuration(50);     
                scaleY.setRepeatCount(5);
                scaleY.setRepeatMode(Animation.REVERSE);
                set.play(scaleX).with(scaleY);
                set.start();

Thanks

Answer

princeparadoxes picture princeparadoxes · May 28, 2016

For ValueAnimator and ObjectAnimator can be like this a try:

animator.addListener(new AnimatorListenerAdapter() {
    @Override
    public void onAnimationEnd(Animator animation) {
        animation.removeListener(this);
        animation.setDuration(0);
        ((ValueAnimator) animation).reverse();
    }
});

UPDATE On Android 7 it doesn't work. Best way use the interpolator.

public class ReverseInterpolator implements Interpolator {

    private final Interpolator delegate;

    public ReverseInterpolator(Interpolator delegate){
        this.delegate = delegate;
    }

    public ReverseInterpolator(){
        this(new LinearInterpolator());
    }

    @Override
    public float getInterpolation(float input) {
        return 1 - delegate.getInterpolation(input);
    }
}

In your code

animator.addListener(new AnimatorListenerAdapter() {
        @Override
        public void onAnimationEnd(Animator animation) {
            animation.removeListener(this);
            animation.setDuration(0);
            animation.setInterpolator(new ReverseInterpolator());
            animation.start();
        }
});