Question

I have a problem. I want to animate the background color of a LinearLayout, using ObjectAnimator.
The problem is that it animates, but it does neither care about duration nor valueFrom and valueTo.

This is my xml file:

<objectAnimator xmlns:android="http://schemas.android.com/apk/res/android"
    android:duration="2000"
    android:propertyName="backgroundColor"
    android:repeatCount="infinite"
    android:repeatMode="reverse"
    android:valueFrom="#FF0000"
    android:valueTo="#000000" />

In Java I call like this:

ObjectAnimator objAnim = (ObjectAnimator)AnimatorInflater.loadAnimator(getActivity(), R.animator.animator_bkg);
objAnim.setTarget(view);
objAnim.start();

Note that when I animate the alpha of the layout, it works as expected.
Is this an Android bug (4.0.3 on Asus Transformer), or I miss something?

Answer 1

I googled a bit. There is an answer. Try to use TransitionDrawable. http://developer.android.com/guide/topics/resources/drawable-resource.html#Transition

Also, there is a topic somewhere on stackoverflow.com dedicated to the same problem.

ADDED Code example:

    Button btn = (Button)this.findViewById(R.id.btn1);
    //Let's change background's color from blue to red.
    ColorDrawable[] color = {new ColorDrawable(Color.BLUE), new ColorDrawable(Color.RED)};
    TransitionDrawable trans = new TransitionDrawable(color);
    //This will work also on old devices. The latest API says you have to use setBackground instead.
    btn.setBackgroundDrawable(trans);
    trans.startTransition(5000);