private void notifyProgress(int value, boolean fromUser) {
        if (mPublicChangeListener != null) {
            mPublicChangeListener.onProgressChanged(DiscreteSeekBar.this, value, fromUser);
        }
        onValueChanged(value);
    }
If {@code enabled} is false the indicator won't appear. By default popup indicator is
enabled.
app/src/main/java/com/duan/musicoco/view/discreteseekbar/DiscreteSeekBar.java