@Override
    public boolean isRunning() {
        final ArrayList<Animation> animators = mAnimators;
        final int N = animators.size();
        for (int i = 0; i < N; i++) {
            final Animation animator = animators.get(i);
            if (animator.hasStarted() && !animator.hasEnded()) {
                return true;
            }
        }
        return false;
    }
Set the colors used in the progress animation from color resources.
The first color will also be the color of the bar that grows in response
to a user swipe gesture.

@param colors
ptr-lib/src/in/srain/cube/views/ptr/header/MaterialProgressDrawable.java