public void setFraction(float fraction) {
        mTimingVisualizer.setFraction(fraction);
        mVisualizer.setFraction(fraction);
    }
This method is called by the animation to update the position of the animated
objects in the curve view as well as the view at the bottom showing sample animations.
AnimationsInterpolatorPlayground/app/src/main/java/com/example/android/interpolatorplayground/MainActivity.java