@OnClick(R.id.save_button)
  void onSaveClicked() {
    if (mInterface != null) {

      if (mode == MODE_NEW_BOOK) mInterface.onSaveClicked(mBook);
      else showConfirmArea();
    }
  }
 @OnClick(R.id.delete_button)
 void onDeleteClicked() {
   if (mInterface != null) {
     mInterface.onCancelClicked();
   }
 }
 @OnClick(R.id.yes)
 void onConfirmDeleteClicked() {
   if (mode != MODE_NEW_BOOK) mInterface.onDeleteClicked(mBook);
 }