@Nullable
    @Override
    public ListModel<JdkComboBoxItem> onChosen(JdkComboBoxItem selectedValue) {
      if (selectedValue instanceof InnerComboBoxItem) {
        SdkListModel inner = myInnerModel.onChosen(((InnerComboBoxItem)selectedValue).getItem());
        return inner == null ? null : new JdkComboBoxModel(inner);
      }
      return null;
    }
@Nullable
    @Override
    public ListModel<JdkComboBoxItem> onChosen(JdkComboBoxItem selectedValue)