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Android Animations and Transitions The Transitions Framework Create a Custom Transition

Posted by Malcolm Mutambanengwe
Malcolm Mutambanengwe
4,205 Points

custom animation

I'm doing exactly as instructed in the video. Am I missing something? Steve Hunter

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

    @Override
    public Animator onDisappear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues) {
        return createAlphaScaleAnimator(view, 1, 0);
    }

    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;
    }
}

2 Answers

Steve Hunter
Steve Hunter
57,712 Points

Hi Mal,

Have a look at what the createAlphaScaleAnimator method needs to receive as arguments. It wants a View and four floats. Pass in those; the onAppear goes from zero to 1 for both the scale and alpha so that looks like:

    public Animator onAppear(ViewGroup sceneRoot, View view, TransitionValues startValues, TransitionValues endValues) {
        return createAlphaScaleAnimator(view, 0, 1, 0, 1);  // 5 arguments
    }

I hope that helps,

Steve.

Emmanuel Chiraerae
Emmanuel Chiraerae
6,029 Points

thank you was also stuck here

Malcolm Mutambanengwe
Malcolm Mutambanengwe
4,205 Points
Malcolm Mutambanengwe
Malcolm Mutambanengwe
4,205 Points

Ok I see. A thousand thanks ;)