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Android Animations and Transitions The Transitions Framework Create a Custom Transition

animations and transitions

Challenge Task 2 of 2

Now reverse the transition in onDisappear()! :)

public class AlphaScale extends Visibility {
    public Animator onAppear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues) {
      return createAlphaScaleAnimator (view, 0,1,0,1);


    public Animator onDisappear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues) {
        return null;

    private Animator createAlphaScaleAnimator(View view, float fromScale, float toScale, float fromAlpha, float toAlpha) {
        AnimatorSet set = new AnimatorSet();
        ObjectAnimator x = ObjectAnimator.ofFloat(view, View.SCALE_X, fromScale, toScale);
        ObjectAnimator y = ObjectAnimator.ofFloat(view, View.SCALE_Y, fromScale, toScale);
        ObjectAnimator alpha = ObjectAnimator.ofFloat(view, View.ALPHA, fromAlpha, toAlpha);
        set.playTogether(x, y, alpha);
        return set;