private void updateModel() {
      RadButtonGroup[] groups = myRootContainer.getButtonGroups();
      RadButtonGroup[] allGroups = new RadButtonGroup[groups.length+2];
      System.arraycopy(groups, 0, allGroups, 1, groups.length);
      allGroups [allGroups.length-1] = RadButtonGroup.NEW_GROUP;
      myCbx.setModel(new DefaultComboBoxModel<>(allGroups));
      myCbx.setSelectedItem(FormEditingUtil.findGroupForComponent(myRootContainer, myComponent));
    }
private void updateModel()