@Override
    public void onOpeningComplete() {
        mNumber.setVisibility(View.VISIBLE);
        if (getParent() instanceof MarkerDrawable.MarkerAnimationListener) {
            ((MarkerDrawable.MarkerAnimationListener) getParent()).onOpeningComplete();
        }
    }
{@link ViewGroup} to be used as the real indicator.
<p>
I've used this to be able to accommodate the TextView
with the required positions and offsets
</p>

@hide
app/src/main/java/com/duan/musicoco/view/discreteseekbar/internal/Marker.java