JavaFX 2.0 Activating a Menu like a MenuItem

I'm making a MenuBar, and I wan't the functionality to press a Menu like: "File" and then execute a action. Such like opening an other fxml, or an example where some output is written.

I want the functionality of a MenuItem (lie "About") in a Menu like "File".

package model;

import static java.lang.System.out;

import javafx.application.Application;
import javafx.beans.property.ReadOnlyDoubleProperty;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.geometry.Pos;
import javafx.geometry.Side;
import javafx.scene.Group;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.input.KeyCode;
import javafx.scene.input.KeyCodeCombination;
import javafx.scene.input.KeyCombination;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.VBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

/**
 * Example of creating menus in JavaFX.
 * 
 * @author Dustin
 */
public class JavaFxMenus extends Application
{
   /**
    * Build menu bar with included menus for this demonstration.
    * 
    * @param menuWidthProperty Width to be bound to menu bar width.
    * @return Menu Bar with menus included.
    */
   private MenuBar buildMenuBarWithMenus(final ReadOnlyDoubleProperty menuWidthProperty)
   {
      final MenuBar menuBar = new MenuBar();

      // Prepare left-most 'File' drop-down menu
      final Menu fileMenu = new Menu("File");

      menuBar.getMenus().add(fileMenu);
      //menuBar.getOnMouseClicked().handle(this);


      // Prepare 'Examples' drop-down menu
      final Menu examplesMenu = new Menu("JavaFX 2.0 Examples");
      examplesMenu.getItems().add(new MenuItem("Text Example"));
      examplesMenu.getItems().add(new MenuItem("Objects Example"));
      examplesMenu.getItems().add(new MenuItem("Animation Example"));
      menuBar.getMenus().add(examplesMenu);

      // Pre