/*
  * @see DialogField#dialogFieldChanged
  * Hooks in to get element changes to update check model.
  */
 @Override
 public void dialogFieldChanged() {
   for (int i = fCheckElements.size() - 1; i >= 0; i--) {
     if (!fElements.contains(fCheckElements.get(i))) {
       fCheckElements.remove(i);
     }
   }
   super.dialogFieldChanged();
 }
 private void checkStateChanged() {
   // call super and do not update check model
   super.dialogFieldChanged();
 }