void showGroupChooser(GroupItem defaultGroup) {
    myGroupLabel.setVisible(true);
    myGroupComboBox.setVisible(true);
    List<GroupItem> groups = Palette.getInstance(myProject).getGroups();
    myGroupComboBox.setModel(new DefaultComboBoxModel(groups.toArray()));
    myGroupComboBox.setSelectedItem(defaultGroup);
    myGroupComboBox.addItemListener(new ItemListener() {
      @Override
      public void itemStateChanged(ItemEvent e) {
        updateOKAction();
      }
    });
    updateOKAction();
  }
void showGroupChooser(GroupItem defaultGroup)