code: public void showAlertAddDialog(HistoryReference ref) {
          if (dialogAlertAdd == null || !dialogAlertAdd.isVisible()) {
              dialogAlertAdd = new AlertAddDialog(getView().getMainFrame(), false);
              dialogAlertAdd.setVisible(true);
              dialogAlertAdd.setHistoryRef(ref);
          }
      }
docs: Shows the Add Alert dialogue, to add a new alert for the given {@code HistoryReference}.
  
  @param ref the history reference for the alert.
  @since 2.7.0