android animatorset memory management, freeing up memory from imageview

Question

I have a repeating AnimatorSet that uses a sequence of full frame images on several different activities. I'm getting an out of memory exception as it seems that the imageviews are taking up too much memory.

Originally the activities in the background still had their animations running in a loop taking up memory. I tried remedying by creating and ending animations on pause/resume so that memory from animations in the non-foreground views are reclaimed but I think I need to do more to clear out the imageviews from memory as well.

@Override
protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_face_o_matic_start);
        getActionBar().hide();

}

@Override
protected void onResume() {
    super.onResume();
    createAnimations();
}


@Override
protected void onPause() {
    super.onPause();
    this.mAnimatorSet.removeAllListeners();
    this.mAnimatorSet.end();
            //TODO: clear and free up the memory from the image views somehow
            // this is the part I need help with I think

}

protected ObjectAnimator getGlowAnimation(View v, int duration){
    ObjectAnimator animation = ObjectAnimator.ofFloat(v, "alpha", 0f, 1f);
    animation.setDuration(duration);
    animation.setRepeatCount(1);
    animation.setRepeatMode(Animation.REVERSE);
    return animation;
}

public void createAnimations(){

    //TODO: destroy these imageviews to reclaim memory on pause
            // originally had them in on create but the imageviews continued to
            // take up memory when the activity went into the background
    /*start animations */

    final ImageView bg1 = (ImageView) findViewById(R.id.bg_face_o_matic_1);
    final ImageView bg2 = (ImageView) findViewById(R.id.bg_face_o_matic_2);
    final ImageView bg3 = (ImageView) findViewById(R.id.bg_face_o_matic_3);
    final ImageView bg4 = (ImageView) findViewById(R.id.bg_face_o_matic_4);
    final ImageView bg5 = (ImageView) findViewById(R.id.bg_face_o_matic_5);
    final ImageView bg6 = (ImageView) findViewById(R.id.bg_face_o_matic_6);

    ObjectAnimator anim1 = getGlowAnimation(bg1, 400);
    ObjectAnimator anim2 = getGlowAnimation(bg2, 400);      
    ObjectAnimator anim3 = getGlowAnimation(bg3, 400);
    ObjectAnimator anim4 = getGlowAnimation(bg4, 400);
    ObjectAnimator anim5 = getGlowAnimation(bg5, 400);
    ObjectAnimator anim6 = getGlowAnimation(bg6, 400);

    List<Animator> animations = new ArrayList<Animator>(Arrays.asList(anim1, anim2, anim3, anim4, anim5, anim6));
    mAnimatorSet.playSequentially(animations);
            //loop the animator set
    mAnimatorSet.addListener(new AnimatorListenerAdapter(){

        @Override
        public void onAnimationEnd(Animator animation) {
            super.onAnimationEnd(animation);
            mAnimatorSet.start();

        }

    });

    mAnimatorSet.start();
    /*end animations */
}

Answer 1

Everytime your application enters this Activity it calls your onResume() method, in which it calls createAnimations(), hence it is continuously creating lots of images and other stuff. You should declare some stuff outside of this method, declare them on class-level and init them in onCreate() so it will be much more efficient. I reduced your createAnimations() a bit. And just call this method once in your onCreate() after you initialize its necessary dependency variables and in your onResume() just call mAnimatorSet.playSequentially(animations);

public void createAnimations(){


    mAnimatorSet.playSequentially(animations);
            //loop the animator set
    mAnimatorSet.addListener(new AnimatorListenerAdapter(){

        @Override
        public void onAnimationEnd(Animator animation) {
            super.onAnimationEnd(animation);
            mAnimatorSet.start();

        }

    });
}