Xamarin Android back button event during ActionMode

When a user presses the back button during an ActionMode, OnBackPressed() doesn't get called, s0 how to do we intercept this event if we need to do something?

Like this:

 public override bool DispatchKeyEvent(KeyEvent keyevent)
        {
            if (_contextualActionBar != null && ItemsInEditMode.Any())
            {
                if (keyevent.KeyCode == KeyEvent.KeyCodeFromString("KEYCODE_BACK") && keyevent.Action == KeyEventActions.Up)
                {
                    DeselectallItems(_listOfItems);
                    KillActionBar();
                    return true;
                }
            }
            return base.DispatchKeyEvent(keyevent);
        }