// The "MenuDemo" class.

import javax.swing.*;

import java.awt.Color;

import java.awt.Dimension;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.ItemEvent;

import java.awt.event.ItemListener;

import java.awt.event.KeyEvent;

public class MenuDemo implements ActionListener, ItemListener //ItemListener is for checkboxes in menu

{

JFrame frame;

JPanel myPanel;

JMenuBar mainMenu;

JMenu gameMenu, subMenu, levelMenu, helpMenu;

JMenuItem newOption, exitOption, aboutOption, subMenuOne, subMenuTwo;

JLabel label;

JCheckBoxMenuItem beginnerOption, intermediateOption, advancedOption;

String message;

int level;

public MenuDemo ()

{

frame = new JFrame ("Working with Menus");

myPanel = new JPanel ();

myPanel.setPreferredSize(new Dimension(400, 400));

myPanel.setLocation (300,300);

myPanel.setLayout (new BoxLayout (myPanel, BoxLayout.PAGE_AXIS));

myPanel.setBackground (Color.white);

myPanel.setBorder (BorderFactory.createEmptyBorder (10,10,10,10));

// Set up the Menu

// Set up the Game MenuItems with Short cuts

newOption = new JMenuItem ("New", KeyEvent.VK_N);

exitOption = new JMenuItem ("Exit", KeyEvent.VK_X);

// Set up the Game Menu

gameMenu = new JMenu ("Game");

// Add each MenuItem to the Game Menu (with a separator)

gameMenu.add (newOption);

// Create a sub menu

subMenu = new JMenu ("Sub Menu");

subMenuOne = new JMenuItem ("First Sub Menu Choice");

subMenuTwo = new JMenuItem ("Second Sub Menu Choice");

subMenu.add (subMenuOne);

subMenu.add (subMenuTwo);

gameMenu.add (subMenu);

gameMenu.addSeparator ();

gameMenu.add (exitOption);

// Set up the Level Menu with the check boxes

beginnerOption = new JCheckBoxMenuItem ("Beginner", true);

level = 1;

intermediateOption = new JCheckBoxMenuItem ("Intermediate", false);

advancedOption = new JCheckBoxMenuItem ("Advanced", false);

levelMenu = new JMenu ("Level");

levelMenu.add (beginnerOption);

levelMenu.add (intermediateOption);

levelMenu.add (advancedOption);

// Set up the Help Menu

aboutOption = new JMenuItem ("About...");

helpMenu = new JMenu ("Help");

helpMenu.add (aboutOption);

// Set up the Menu Bar and add the above Menus

mainMenu = new JMenuBar ();

mainMenu.add (gameMenu);

mainMenu.add (levelMenu);

//mainMenu.setHelpMenu (helpMenu);

mainMenu.add (helpMenu);

// Set the menu bar for this frame to mainMenu

frame.setJMenuBar (mainMenu);

label = new JLabel ("Welcome to the Menu Demo"); // initial message

myPanel.add (label);

newOption.setActionCommand ("New");

newOption.addActionListener(this);

exitOption.setActionCommand ("Exit");

exitOption.addActionListener(this);

aboutOption.setActionCommand ("About");

aboutOption.addActionListener(this);

subMenuOne.setActionCommand ("SubMenu1");

subMenuOne.addActionListener(this);

subMenuTwo.setActionCommand ("SubMenu2");

subMenuTwo.addActionListener(this);

beginnerOption.setActionCommand ("Beginner");

beginnerOption.addItemListener(this);

intermediateOption.setActionCommand ("Intermediate");

intermediateOption.addItemListener(this);

advancedOption.setActionCommand ("Advanced");

advancedOption.addItemListener(this);

frame.add(myPanel);

frame.pack();

frame.setVisible(true);

}

// To handle normal menu items

public void actionPerformed (ActionEvent event) {

String eventName = event.getActionCommand();

if (eventName.equals ("New")) {

newGame ();

}

else if (eventName.equals ("SubMenu1"))

label.setText ("First Sub Menu Choice Selected");

else if (eventName.equals ("SubMenu2"))

label.setText ("Second Sub Menu Choice Selected");

else if (eventName.equals ("Exit")) {

System.exit (0);

}

else if (eventName.equals ("About"))

JOptionPane.showMessageDialog (frame, (Object) "Menu Event \nProcessing Demo", "About...", JOptionPane.INFORMATION_MESSAGE);

}

// To handle menu items that are checkboxes or radio buttons

public void itemStateChanged(ItemEvent event) {

if (event.getSource() == beginnerOption)

label.setText ("Beginner level selected");

else if (event.getSource () == intermediateOption)

label.setText ("Intermediate level selected");

else if (event.getSource () == advancedOption)

label.setText ("Advanced level selected");

}

public void newGame ()

{

message = "New Game Selected at the ";

if (level == 1)

message += "Beginner Level";

else if (level == 2)

message += "Intermediate Level";

else

message += "Advanced Level";

}

public static void main (String [] args){

new MenuDemo ();

}

}