JavaFX 2.0 Activating a Menu like a MenuItem

Question

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);

      // Prepare 'Help' drop-down menu
      final Menu helpMenu = new Menu("Help");
      helpMenu.setOnAction(null);

      final MenuItem searchMenuItem = new MenuItem("Search");
      searchMenuItem.setDisable(true);
      helpMenu.getItems().add(searchMenuItem);
      final MenuItem onlineManualMenuItem = new MenuItem("Online Manual");
      onlineManualMenuItem.setVisible(false);
      helpMenu.getItems().add(onlineManualMenuItem);
      helpMenu.getItems().add(new SeparatorMenuItem());
      final MenuItem aboutMenuItem =
         MenuItemBuilder.create()
                        .text("About")
                        .onAction(
                            new EventHandler<ActionEvent>()
                            {
                               @Override public void handle(ActionEvent e)
                               {
                                  out.println("You clicked on About!");
                               }
                            })
                        .accelerator(
                            new KeyCodeCombination(
                               KeyCode.A, KeyCombination.CONTROL_DOWN))
                        .build();             
      helpMenu.getItems().add(aboutMenuItem);
      menuBar.getMenus().add(helpMenu);

      // bind width of menu bar to width of associated stage
      menuBar.prefWidthProperty().bind(menuWidthProperty);

      return menuBar;
   }

   /**
    * Start of JavaFX application demonstrating menu support.
    * 
    * @param stage Primary stage.
    */
   @Override
   public void start(final Stage stage)
   {
      stage.setTitle("Creating Menus with JavaFX 2.0");
      final Group rootGroup = new Group();
      final Scene scene = new Scene(rootGroup, 800, 400, Color.WHEAT);



      final MenuBar menuBar = buildMenuBarWithMenus(stage.widthProperty());
      rootGroup.getChildren().add(menuBar);
      stage.setScene(scene);
      stage.show();
   }

   /**
    * Main executable function for running examples.
    * 
    * @param arguments Command-line arguments: none expected.
    */
   public static void main(final String[] arguments)
   {
      Application.launch(arguments);
   }
}

Answer 1

AFAIK, A Menu, if has not any added submenu or Menuitems, does not fire events neither on click, on shown nor on hide. However the workaround is to set its graphic where this graphic node will handle mouse clicks for example,

Label menuLabel = new Label("File");
menuLabel.setOnMouseClicked(new EventHandler<MouseEvent>() {
    @Override
    public void handle(MouseEvent event) {

        Stage myDialog = new Stage();
        myDialog.initModality(Modality.WINDOW_MODAL);

        Scene myDialogScene = new Scene(VBoxBuilder.create()
            .children(new Text("Hello! it's My Dialog."))
            .alignment(Pos.CENTER)
            .padding(new Insets(10))
            .build());

        myDialog.setScene(myDialogScene);
        myDialog.show();
    }
});
Menu fileMenuButton = new Menu();
fileMenuButton.setGraphic(menuLabel);
menuBar.getMenus().add(fileMenuButton);

A drawback of this approach is that the label do not cover all spaces of the menu resulting clicking on edges of menu is not triggering the mouse event. See this by uncommenting menuLabel.setStyle line above. But this can be resolved by playing with CSS styles I think.
Code is partially taken from Create Dialog using Stage. You can also load an FXML file into the myDialog stage using the FXMLLoader. There are lots of examples about it on the net.

Answer 2

Recently i had the same problem, this is what i did

@FXML private Menu myMenu;

@Override
public void initialize(URL url, ResourceBundle rb) {

    myMenu.setGraphic(
        ButtonBuilder.create()
            .text("btnText")
            .onAction(new EventHandler<ActionEvent>(){
                @Override public void handle(ActionEvent t) {
                    //TODO
             } })
            .build()
    );
}

Answer 3

Combining with the answer from our friend @Dota2, i built a helper class to trigger the Menu's onAction(Menu menu) event even if it does not have any MenuItem inside. Here is the static helper method:

public static void onAction(Menu menu)
{
    final MenuItem menuItem = new MenuItem();

    menu.getItems().add(menuItem);
    menu.addEventHandler(Menu.ON_SHOWN, event -> menu.hide());
    menu.addEventHandler(Menu.ON_SHOWING, event -> menu.fire());
}

Then you call:

YourHelperClass.onAction(myMenu);

And ready! I hope this helps.

Answer 4

Recently I faced the same issue, this was my way out:

I had a menuItem in the menu, which was to behave as if the menuItem is clicked (in your case File menu). So what you can do is have a menuItem Dummy_menuItem

final Menu fileMenu = new Menu("File");
fileMenu.getItems().add(new MenuItem("Dummy_menuItem"));
menuBar.getMenus().add(fileMenu);

and then on click of File menu, fire the Dummy_menuItem menuItem or any functionality you wish to have. To identify which menu should have this property, I used numberOfMenuItems to get the number of menuItems in the menus in menubar

if (numberOfMenuItems == 1) {
    menu.showingProperty().addListener(
        (observableValue, oldValue, newValue) -> {
            if (newValue) {
                // the first menuItem is triggered
                menu.getItems().get(0).fire();
            }
        }
    );
}

the outcome is that the Dummy_menuItem is triggered without the context displaying the menuItem on click of File menu or any menu that has one menuItem. So it appears as if you clicked the File menu and were redirected to another page or whatever.

Hope this helps!!

Answer 5

I think you can't allow any action on the main Menu label.

However, you can create a stackpane, and fill it with text and a menu bar.