JavaFX 2.0 Activating a Menu like a MenuItem

haakonlu picture haakonlu · Apr 25, 2012 · Viewed 24.4k times · Source

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

Uluk Biy picture Uluk Biy · Apr 25, 2012

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.