@Override
  public void showContentPopup(ListPopup listPopup) {
    Content selected = ui.getContentManager().getSelectedContent();
    if (selected != null) {
      ContentTabLabel tab = contentToTabs.get(selected);
      listPopup.showUnderneathOf(tab);
    }
    else {
      listPopup.showUnderneathOf(idLabel);
    }
  }
@Override
  public void showContentPopup(ListPopup listPopup)