Android onAnimationEnd called twice

问题:

i have created a SLIDE UP animation on view and i am repeating this animation again onAnimationEnd but my onAnimationEnd fired twice , i have checked it with counter at onAnimationEnd , i will post my code, you can check that the counter in onAnimationEnd will incremented twice at same time , I am starting the animation again in onAnimationEnd method , please guide me where i am doing wrong?

    private Animation animSlideUp;
        animSlideUp = AnimationUtils.loadAnimation(getActivity(), R.anim.slide_up);
                // set animation listener
                animSlideUp.setAnimationListener(this);
                animSlideUp.setDuration(500);
                animSlideUp.setStartOffset(5000);

                tickerView.startAnimation(animSlideUp);

        @Override
        public void onAnimationStart(Animation animation) {

        }

        @Override
        public void onAnimationEnd(Animation animation) {
            if (animation == animSlideUp) {
                ticker_counter++;
                Log.e("onAnimationEnd=", "ticker_counter="+ticker_counter);
                tickerView.startAnimation(animSlideUp);

            }
        }

        @Override
        public void onAnimationRepeat(Animation animation) {
        }

slide_up.xml

<?xml version="1.0" encoding="utf-8"?>
<set xmlns:android="http://schemas.android.com/apk/res/android"
    android:fillAfter="true" >

    <scale
        android:duration="500"
        android:fromXScale="1.0"
        android:fromYScale="1.0"
        android:interpolator="@android:anim/linear_interpolator"
        android:toXScale="1.0"
        android:toYScale="0.0"/>

</set>
LOGCAT

    11-19 17:06:54.375   E/onAnimationEnd=﹕ ticker_counter=1
    11-19 17:06:54.392   E/onAnimationEnd=﹕ ticker_counter=2
    11-19 17:06:59.912   E/onAnimationEnd=﹕ ticker_counter=3
    11-19 17:06:59.928   E/onAnimationEnd=﹕ ticker_counter=4
    11-19 17:07:05.453   E/onAnimationEnd=﹕ ticker_counter=5
    11-19 17:07:05.470   E/onAnimationEnd=﹕ ticker_counter=6
    11-19 17:07:10.991   E/onAnimationEnd=﹕ ticker_counter=7
    11-19 17:07:11.008   E/onAnimationEnd=﹕ ticker_counter=8

回答1:

If you want your animation to play once, you have to remove tickerView.startAnimation(animSlideUp); from the onAnimationEnd Method.
Avoid using xml animations, it's much easier in java code.
If you're trying to animate two properties :

PropertyValuesHolder pvhX = PropertyValuesHolder.ofFloat("scaleX", 1.0f, 0);
PropertyValuesHolder pvhY = PropertyValuesHolder.ofFloat("scaleY", 1.0f, 0);
ObjectAnimator animator = ObjectAnimator.ofPropertyValuesHolder(tickerView, pvhX, pvhY);
        animator.setDuration(500);
        animator.start();

In your case, you're only changing the scaleY value from 1.0 to 0, so use this :

ObjectAnimator animator = ObjectAnimator.ofFloat(tickerView, "scaleY",0);
animator.setDuration(500);
//To repeat twice if you want to
animator.setRepeatCount(1);
animator.start();

LinearInterpolator is used by default.

Repeat after every 5 sec

    final ObjectAnimator animator = ObjectAnimator.ofFloat(tickerView, "scaleY", 0);
    animator.setDuration(500);
    animator.addListener(new Animator.AnimatorListener() {
        @Override
        public void onAnimationStart(Animator animation) {
        }

        @Override
        public void onAnimationEnd(Animator animation) {
            ticker_counter++;
            animation.setStartDelay(5000);
            animator.start();
        }

        @Override
        public void onAnimationCancel(Animator animation) {

        }

        @Override
        public void onAnimationRepeat(Animator animation) {
        }
    });
    animator.start();

回答2:

I may found the solution: post an runnable to restart the animation.

In your case , in OnAnimationEnd() function, code like this:

 @Override
    public void onAnimationEnd(Animation animation) {
        if (animation == animSlideUp) {
            ticker_counter++;
            Log.e("onAnimationEnd=", "ticker_counter="+ticker_counter);
            tickerView.post(new Runnable(){ //post an runnable to start
                tickerView.startAnimation(animSlideUp);
            });

        }
    }

回答3:

I had the same problem and just setting null as listener of second animation worked for me.

setListener(null);

Example:

view.animate()
    .alpha(0F)
    .setDuration(200L)
    .setListener(new Animator.AnimatorListener() {

        @Override
        public void onAnimationStart(Animator animation) {
        }

        @Override
        public void onAnimationEnd(Animator animation) {

            view.animate()
                .alpha(1F)
                .setDuration(200L)
                .setListener(null)
                .start();
        }

        @Override
        public void onAnimationCancel(Animator animation) {
        }

        @Override
        public void onAnimationRepeat(Animator animation) {
        }

    }).start();