Java Tutorial/Swing/JMenu

Adding a Menu to a Window

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
public class AddMenuBarToFrame extends JFrame {
  private JMenuBar menuBar = new JMenuBar(); // Window menu bar
  public AddMenuBarToFrame(String title) {
    setTitle(title);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setJMenuBar(menuBar); // Add the menu bar to the window
    JMenu fileMenu = new JMenu("File"); // Create File menu
    JMenu elementMenu = new JMenu("Elements"); // Create Elements menu
    menuBar.add(fileMenu); // Add the file menu
    menuBar.add(elementMenu); // Add the element menu
  }
  public static void main(String[] args) {
    AddMenuBarToFrame window = new AddMenuBarToFrame("Sketcher"); 
    window.setBounds(30, 30, 300, 300);
    window.setVisible(true);
  }
}

Adding Menu Shortcuts

import static java.awt.event.InputEvent.CTRL_DOWN_MASK;
import javax.swing.ButtonGroup;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JRadioButtonMenuItem;
import javax.swing.KeyStroke;
public class FramewithMenuShortcut extends JFrame {
  private JMenuBar menuBar = new JMenuBar(); // Window menu bar
  private JMenuItem newItem, openItem, closeItem, saveItem, saveAsItem, printItem;
  private JRadioButtonMenuItem lineItem, rectangleItem, circleItem;
  private JCheckBoxMenuItem redItem, yellowItem;
  public FramewithMenuShortcut(String title) {
    JMenu fileMenu = new JMenu("File"); // Create File menu
    JMenu elementMenu = new JMenu("Elements"); // Create Elements menu
    fileMenu.setMnemonic("F"); // Create shortcut
    elementMenu.setMnemonic("E"); // Create shortcut
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setJMenuBar(menuBar);
    newItem = fileMenu.add("New");
    openItem = fileMenu.add("Open");
    closeItem = fileMenu.add("Close");
    fileMenu.addSeparator();
    saveItem = fileMenu.add("Save");
    saveAsItem = fileMenu.add("Save As...");
    fileMenu.addSeparator();
    printItem = fileMenu.add("Print");
    elementMenu.add(lineItem = new JRadioButtonMenuItem("Line", true));
    elementMenu.add(rectangleItem = new JRadioButtonMenuItem("Rectangle", false));
    elementMenu.add(circleItem = new JRadioButtonMenuItem("Circle", false));
    ButtonGroup types = new ButtonGroup();
    types.add(lineItem);
    types.add(rectangleItem);
    types.add(circleItem);
    elementMenu.addSeparator();
    elementMenu.add(redItem = new JCheckBoxMenuItem("Red", false));
    elementMenu.add(yellowItem = new JCheckBoxMenuItem("Yellow", false));
    menuBar.add(fileMenu);
    menuBar.add(elementMenu);
    newItem.setAccelerator(KeyStroke.getKeyStroke("N", CTRL_DOWN_MASK));
    openItem.setAccelerator(KeyStroke.getKeyStroke("O", CTRL_DOWN_MASK));
    saveItem.setAccelerator(KeyStroke.getKeyStroke("S", CTRL_DOWN_MASK));
    printItem.setAccelerator(KeyStroke.getKeyStroke("P", CTRL_DOWN_MASK));
    lineItem.setAccelerator(KeyStroke.getKeyStroke("L", CTRL_DOWN_MASK));
    rectangleItem.setAccelerator(KeyStroke.getKeyStroke("E", CTRL_DOWN_MASK));
    circleItem.setAccelerator(KeyStroke.getKeyStroke("I", CTRL_DOWN_MASK));
    elementMenu.addSeparator();
    redItem.setAccelerator(KeyStroke.getKeyStroke("R", CTRL_DOWN_MASK));
    yellowItem.setAccelerator(KeyStroke.getKeyStroke("Y", CTRL_DOWN_MASK));
    menuBar.add(fileMenu);
    menuBar.add(elementMenu);
  }
  public static void main(String[] a) {
    FramewithMenuShortcut window = new FramewithMenuShortcut("");
    window.setBounds(30, 30, 300, 300);
    window.setVisible(true);
  }
}

Add Separator to JMenu

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JSeparator;
public class MenuSeparator extends JFrame {
  public MenuSeparator() {
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JMenuBar bar = new JMenuBar();
    JMenu menu = new JMenu("File");
    bar.add(menu);
    menu.add(new JMenuItem("Close"));
    menu.add(new JSeparator()); // SEPARATOR
    menu.add(new JMenuItem("Exit"));
    setJMenuBar(bar);
    getContentPane().add(new JLabel("A placeholder"));
    pack();
    setSize(300, 300);
    setVisible(true);
  }
  public static void main(String arg[]) {
    new MenuSeparator();
  }
}

Customizing JMenu Look and Feel

Property StringObject TypeMenu.acceleratorDelimiterStringMenu.acceleratorFontFontMenu.acceleratorForegroundColorMenu.acceleratorSelectionForegroundColorMenu.ActionMapActionMapMenu.arrowIconIconMenu.backgroundColorMenu.borderBorderMenu.borderPaintedBooleanMenu.checkIconIconMenu.delayIntegerMenu.disabledForegroundColorMenu.fontFontMenu.foregroundColorMenu.marginInsetsMenu.menuPopupOffsetXIntegerMenu.menuPopupOffsetYIntegerMenu.opaqueBooleanMenu.selectionBackgroundColorMenu.selectionForegroundColorMenu.shortcutKeysint[ ]Menu.submenuPopupOffsetXIntegerMenu.submenuPopupOffsetYIntegerMenu.textIconGapIntegerMenu.useMenuBarBackgroundForTopLevelBooleanmenuPressedItemBColormenuPressedItemFColormenuTextColorMenuUIString

Layout menu yourself

/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import javax.swing.BorderFactory;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JPopupMenu;
/**
 * @author ges
 * @author kwalrath
 */
/* MenuLayoutDemo.java requires no other files. */
public class MenuLayoutDemo {
  public JMenuBar createMenuBar() {
    JMenuBar menuBar = new JMenuBar();
    menuBar.setLayout(new BoxLayout(menuBar, BoxLayout.PAGE_AXIS));
    menuBar.add(createMenu("Menu 1"));
    menuBar.add(createMenu("Menu 2"));
    menuBar.add(createMenu("Menu 3"));
    menuBar.setBorder(BorderFactory.createMatteBorder(0, 0, 0, 1, Color.BLACK));
    return menuBar;
  }
  // used by createMenuBar
  public JMenu createMenu(String title) {
    JMenu m = new HorizontalMenu(title);
    m.add("Menu item #1 in " + title);
    m.add("Menu item #2 in " + title);
    m.add("Menu item #3 in " + title);
    JMenu submenu = new HorizontalMenu("Submenu");
    submenu.add("Submenu item #1");
    submenu.add("Submenu item #2");
    m.add(submenu);
    return m;
  }
  /**
   * Create the GUI and show it. For thread safety, this method should be
   * invoked from the event-dispatching thread.
   */
  private static void createAndShowGUI() {
    // Create and set up the window.
    JFrame frame = new JFrame("MenuLayoutDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    // Create and set up the content pane.
    MenuLayoutDemo demo = new MenuLayoutDemo();
    Container contentPane = frame.getContentPane();
    contentPane.setBackground(Color.WHITE); // contrasting bg
    contentPane.add(demo.createMenuBar(), BorderLayout.LINE_START);
    // Display the window.
    frame.setSize(300, 150);
    frame.setVisible(true);
  }
  public static void main(String[] args) {
    // Schedule a job for the event-dispatching thread:
    // creating and showing this application"s GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
  class HorizontalMenu extends JMenu {
    HorizontalMenu(String label) {
      super(label);
      JPopupMenu pm = getPopupMenu();
      pm.setLayout(new BoxLayout(pm, BoxLayout.LINE_AXIS));
    }
    public Dimension getMinimumSize() {
      return getPreferredSize();
    }
    public Dimension getMaximumSize() {
      return getPreferredSize();
    }
    public void setPopupMenuVisible(boolean b) {
      boolean isVisible = isPopupMenuVisible();
      if (b != isVisible) {
        if ((b == true) && isShowing()) {
          // Set location of popupMenu (pulldown or pullright).
          // Perhaps this should be dictated by L&F.
          int x = 0;
          int y = 0;
          Container parent = getParent();
          if (parent instanceof JPopupMenu) {
            x = 0;
            y = getHeight();
          } else {
            x = getWidth();
            y = 0;
          }
          getPopupMenu().show(this, x, y);
        } else {
          getPopupMenu().setVisible(false);
        }
      }
    }
  }
}

Listening to JMenu Events with a ChangeListener: register a ChangeListener with a JMenu

import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;
public class ContructMenuWithAction {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("MenuSample Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JMenuBar menuBar = new JMenuBar();
    // File Menu, F - Mnemonic
    JMenu fileMenu = new JMenu("File");
    fileMenu.setMnemonic(KeyEvent.VK_F);
    menuBar.add(fileMenu);
    fileMenu.addChangeListener(new ChangeListener() {
      public void stateChanged(ChangeEvent e) {
        System.out.println("File Menu Changed");
      }
    });
    // File->New, N - Mnemonic
    JMenuItem newMenuItem = new JMenuItem("New");
    fileMenu.add(newMenuItem);
    newMenuItem.addChangeListener(new ChangeListener() {
      public void stateChanged(ChangeEvent e) {
        System.out.println("new menu item changed");
      }
    });
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}

Set Mnemonic key

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
class MenuActionListener implements ActionListener {
  public void actionPerformed(ActionEvent actionEvent) {
    System.out.println("Selected: " + actionEvent.getActionCommand());
  }
}
public class MenuAction {
  public static void main(final String args[]) {
    ActionListener menuListener = new MenuActionListener();
    JFrame frame = new JFrame("MenuSample Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JMenuBar menuBar = new JMenuBar();
    // File Menu, F - Mnemonic
    JMenu fileMenu = new JMenu("File");
    fileMenu.setMnemonic(KeyEvent.VK_F);
    menuBar.add(fileMenu);
    // File->New, N - Mnemonic
    JMenuItem newMenuItem = new JMenuItem("New", KeyEvent.VK_N);
    newMenuItem.addActionListener(menuListener);
    fileMenu.add(newMenuItem);

    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}

Submenu

import java.awt.event.KeyEvent;
import javax.swing.ButtonGroup;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JRadioButtonMenuItem;
public class Submenu  {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("MenuSample Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JMenuBar menuBar = new JMenuBar();
    // File Menu, F - Mnemonic
    JMenu fileMenu = new JMenu("File");
    fileMenu.setMnemonic(KeyEvent.VK_F);
    menuBar.add(fileMenu);
    // File->New, N - Mnemonic
    JMenuItem newMenuItem = new JMenuItem("New", KeyEvent.VK_N);
    fileMenu.add(newMenuItem);
    // Edit->Options Submenu, O - Mnemonic, at.gif - Icon Image File
    JMenu findOptionsMenu = new JMenu("Options");
    Icon atIcon = new ImageIcon("at.gif");
    findOptionsMenu.setIcon(atIcon);
    findOptionsMenu.setMnemonic(KeyEvent.VK_O);
    fileMenu.add(findOptionsMenu);
    // ButtonGroup for radio buttons
    ButtonGroup directionGroup = new ButtonGroup();
    // Edit->Options->Forward, F - Mnemonic, in group
    JRadioButtonMenuItem forwardMenuItem = new JRadioButtonMenuItem("Forward", true);
    forwardMenuItem.setMnemonic(KeyEvent.VK_F);
    findOptionsMenu.add(forwardMenuItem);
    directionGroup.add(forwardMenuItem);
    // Edit->Options->Backward, B - Mnemonic, in group
    JRadioButtonMenuItem backwardMenuItem = new JRadioButtonMenuItem("Backward");
    backwardMenuItem.setMnemonic(KeyEvent.VK_B);
    findOptionsMenu.add(backwardMenuItem);
    directionGroup.add(backwardMenuItem);
    
    
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}

The JMenu component is the basic menu item container that is placed on a JMenuBar

1. In various places within the different menus, menu separators divide the options into logical sets.
2. Each of the menu options has a mnemonic associated with it to help with keyboard navigation and selection.
3. The mnemonic allows users to make menu selections via the keyboard, for instance, by pressing Alt-F on a Windows platform to open the File menu.
4. A keystroke associated with several options acts as a keyboard accelerator. Unlike the mnemonic, the accelerator can directly activate a menu option, even when the menu option isn"t visible.
5. The Options submenu has an icon associated with it.

JMenu fileMenu = new JMenu("File");
JMenuItem newMenuItem = new JMenuItem("New");
fileMenu.add(newMenuItem);
JMenuItem openMenuItem = new JMenuItem("Open");
fileMenu.add(openMenuItem);
JMenuItem closeMenuItem = new JMenuItem("Close");
fileMenu.add(closeMenuItem);
fileMenu.addSeparator();
JMenuItem saveMenuItem = new JMenuItem("Save");
fileMenu.add(saveMenuItem);
fileMenu.addSeparator();
JMenuItem exitMenuItem = new JMenuItem("Exit");
fileMenu.add(exitMenuItem);

Using Action Objects with Menus

Creating a specific implementation of AbstractAction and adds it to a JMenu multiple times

import java.awt.ruponent;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.AbstractAction;
import javax.swing.Action;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JOptionPane;
class ShowAction extends AbstractAction {
  Component parentComponent;
  public ShowAction(Component parentComponent) {
    super("About");
    putValue(Action.MNEMONIC_KEY, new Integer(KeyEvent.VK_A));
    this.parentComponent = parentComponent;
  }
  public void actionPerformed(ActionEvent actionEvent) {
    Runnable runnable = new Runnable() {
      public void run() {
        JOptionPane.showMessageDialog(parentComponent, "About Swing", "About Box V2.0",
            JOptionPane.INFORMATION_MESSAGE);
      }
    };
    EventQueue.invokeLater(runnable);
  }
}
public class ContructMenuWithAction {
  public static void main(final String args[]) {
    JFrame frame = new JFrame("MenuSample Example");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    JMenuBar menuBar = new JMenuBar();
    // File Menu, F - Mnemonic
    JMenu fileMenu = new JMenu("File");
    fileMenu.setMnemonic(KeyEvent.VK_F);
    menuBar.add(fileMenu);
    // File->New, N - Mnemonic
    JMenuItem newMenuItem = new JMenuItem(new ShowAction(frame));
    fileMenu.add(newMenuItem);
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}

Using MenuListener to listen to: menu canceled, selected and deselected events

With a registered MenuListener, you"re notified when a JMenu is selected before the pop-up menu is opened with the menu"s choices.

public interface MenuListener extends EventListener {
  public void menuCanceled(MenuEvent e);
  public void menuDeselected(MenuEvent e);
  public void menuSelected(MenuEvent e);
}

what menus look like

/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
import java.awt.BorderLayout;
import java.awt.Container;
import java.awt.event.ActionEvent;
import java.awt.event.KeyEvent;
import javax.swing.ButtonGroup;
import javax.swing.ImageIcon;
import javax.swing.JCheckBoxMenuItem;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.JPanel;
import javax.swing.JRadioButtonMenuItem;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.KeyStroke;
/* MenuLookDemo.java requires images/middle.gif. */
/*
 * This class exists solely to show you what menus look like. It has no
 * menu-related event handling.
 */
public class MenuLookDemo {
  JTextArea output;
  JScrollPane scrollPane;
  public JMenuBar createMenuBar() {
    JMenuBar menuBar;
    JMenu menu, submenu;
    JMenuItem menuItem;
    JRadioButtonMenuItem rbMenuItem;
    JCheckBoxMenuItem cbMenuItem;
    // Create the menu bar.
    menuBar = new JMenuBar();
    // Build the first menu.
    menu = new JMenu("A Menu");
    menu.setMnemonic(KeyEvent.VK_A);
    menu.getAccessibleContext().setAccessibleDescription(
        "The only menu in this program that has menu items");
    menuBar.add(menu);
    // a group of JMenuItems
    menuItem = new JMenuItem("A text-only menu item", KeyEvent.VK_T);
    // menuItem.setMnemonic(KeyEvent.VK_T); //used constructor instead
    menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_1,
        ActionEvent.ALT_MASK));
    menuItem.getAccessibleContext().setAccessibleDescription(
        "This doesn"t really do anything");
    menu.add(menuItem);
    ImageIcon icon = createImageIcon("images/middle.gif");
    menuItem = new JMenuItem("Both text and icon", icon);
    menuItem.setMnemonic(KeyEvent.VK_B);
    menu.add(menuItem);
    menuItem = new JMenuItem(icon);
    menuItem.setMnemonic(KeyEvent.VK_D);
    menu.add(menuItem);
    // a group of radio button menu items
    menu.addSeparator();
    ButtonGroup group = new ButtonGroup();
    rbMenuItem = new JRadioButtonMenuItem("A radio button menu item");
    rbMenuItem.setSelected(true);
    rbMenuItem.setMnemonic(KeyEvent.VK_R);
    group.add(rbMenuItem);
    menu.add(rbMenuItem);
    rbMenuItem = new JRadioButtonMenuItem("Another one");
    rbMenuItem.setMnemonic(KeyEvent.VK_O);
    group.add(rbMenuItem);
    menu.add(rbMenuItem);
    // a group of check box menu items
    menu.addSeparator();
    cbMenuItem = new JCheckBoxMenuItem("A check box menu item");
    cbMenuItem.setMnemonic(KeyEvent.VK_C);
    menu.add(cbMenuItem);
    cbMenuItem = new JCheckBoxMenuItem("Another one");
    cbMenuItem.setMnemonic(KeyEvent.VK_H);
    menu.add(cbMenuItem);
    // a submenu
    menu.addSeparator();
    submenu = new JMenu("A submenu");
    submenu.setMnemonic(KeyEvent.VK_S);
    menuItem = new JMenuItem("An item in the submenu");
    menuItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_2,
        ActionEvent.ALT_MASK));
    submenu.add(menuItem);
    menuItem = new JMenuItem("Another item");
    submenu.add(menuItem);
    menu.add(submenu);
    // Build second menu in the menu bar.
    menu = new JMenu("Another Menu");
    menu.setMnemonic(KeyEvent.VK_N);
    menu.getAccessibleContext().setAccessibleDescription(
        "This menu does nothing");
    menuBar.add(menu);
    return menuBar;
  }
  public Container createContentPane() {
    // Create the content-pane-to-be.
    JPanel contentPane = new JPanel(new BorderLayout());
    contentPane.setOpaque(true);
    // Create a scrolled text area.
    output = new JTextArea(5, 30);
    output.setEditable(false);
    scrollPane = new JScrollPane(output);
    // Add the text area to the content pane.
    contentPane.add(scrollPane, BorderLayout.CENTER);
    return contentPane;
  }
  /** Returns an ImageIcon, or null if the path was invalid. */
  protected static ImageIcon createImageIcon(String path) {
    java.net.URL imgURL = MenuLookDemo.class.getResource(path);
    if (imgURL != null) {
      return new ImageIcon(imgURL);
    } else {
      System.err.println("Couldn"t find file: " + path);
      return null;
    }
  }
  /**
   * Create the GUI and show it. For thread safety, this method should be
   * invoked from the event-dispatching thread.
   */
  private static void createAndShowGUI() {
    // Create and set up the window.
    JFrame frame = new JFrame("MenuLookDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    // Create and set up the content pane.
    MenuLookDemo demo = new MenuLookDemo();
    frame.setJMenuBar(demo.createMenuBar());
    frame.setContentPane(demo.createContentPane());
    // Display the window.
    frame.setSize(450, 260);
    frame.setVisible(true);
  }
  public static void main(String[] args) {
    // Schedule a job for the event-dispatching thread:
    // creating and showing this application"s GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
}