Android: Why do Object Animators retain the start value?

Question

I have a mixture of animations running on various scenarios. As an example;

I have a fade-in and fade-out animator on a small circle bitmap. On ACTION_DOWN the fade-in should start and on ACTION_UP, when the fade-in ends, fade-out should run. BUT, if the user picks up the finger before the fade-in ends, it should stop right there (fadein.cancel()), fade-out should start from THAT alpha value. I dont want a new object animator each time, I defined an animator like this in the constructor

    fadein = Objectanimator.ofFloat(bitmap, "alpha", 1.0f);
    fadeOut = Objectanimator.ofFloat(bitmap, "alpha", 0.0f);

What happens is, if I produce the issue as mentioned (picking up the finger fast), the fadeout animator will pick up the alpha value where fade-in left off and it'll RETAIN that. That is, 2nd time onwards it'll NOT pick up a new alpha! Why is that? Whats the workaround? Create new objects each time?

Answer 1

ObjectAnimator class modifies the attributes of the view, so it updates the property of the view using the setter method of the Object property (as per official Android Guide).

So, when fadein animation runs, the alpha value is constantly modified, and when fadein.cancel() executes, the alpha value of the View stops updating. Let's say this value is X.

So, when you start fadeOut, it animates from X to 0.0f.

Whats the workaround?

For fadeOut, use two values imply a starting and ending values

fadeOut = Objectanimator.ofFloat(bitmap, "alpha", 1.0f, 0.0f);