AWT Menu Class

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Menu class

Introduction

The Menu class represents pull-down menu component which is deployed from a menu bar.

Class declaration

Following is the declaration for java.awt.Menu class:

public class Menu
   extends MenuItem
      implements MenuContainer, Accessible

Class constructors

S.N.Constructor & Description
1Menu()Constructs a new menu with an empty label.
2Menu(String label)Constructs a new menu with the specified label.
3Menu(String label, boolean tearOff)Constructs a new menu with the specified label, indicating whether the menu can be torn off.

Class methods

S.N.Method & Description
1MenuItem add(MenuItem mi)Adds the specified menu item to this menu.
2void add(String label)Adds an item with the specified label to this menu.
3void addNotify()Creates the menu’s peer.
4void addSeparator()Adds a separator line, or a hypen, to the menu at the current position.
5int countItems()Deprecated. As of JDK version 1.1, replaced by getItemCount().
6AccessibleContext getAccessibleContext()Gets the AccessibleContext associated with this Menu.
7MenuItem getItem(int index)Gets the item located at the specified index of this menu.
8int getItemCount()Get the number of items in this menu.
9void insert(MenuItem menuitem, int index)Inserts a menu item into this menu at the specified position.
10void insert(String label, int index)Inserts a menu item with the specified label into this menu at the specified position.
11void insertSeparator(int index)Inserts a separator at the specified position.
12boolean isTearOff()Indicates whether this menu is a tear-off menu.
13String paramString()Returns a string representing the state of this Menu.
14void remove(int index)Removes the menu item at the specified index from this menu.
15void remove(MenuComponent item)Removes the specified menu item from this menu.
16void removeAll()Removes all items from this menu.
17void removeNotify()Removes the menu’s peer.

Methods inherited

This class inherits methods from the following classes:

  • java.awt.MenuItem
  • java.awt.MenuComponent
  • java.lang.Object

Menu Example

Create the following java program using any editor of your choice in say D:/ > AWT > com > adglob> gui >AWTMenuDemo.java

package com.adglob.gui;

import java.awt.*;
import java.awt.event.*;

public class AWTMenuDemo {
   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;

   public AWTMenuDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AWTMenuDemo  awtMenuDemo = new AWTMenuDemo();     
      awtMenuDemo.showMenuDemo();
   }

   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showMenuDemo(){
      //create a menu bar
      final MenuBar menuBar = new MenuBar();

      //create menus
      Menu fileMenu = new Menu("File");
      Menu editMenu = new Menu("Edit"); 
      final Menu aboutMenu = new Menu("About");

      //create menu items
      MenuItem newMenuItem = 
         new MenuItem("New",new MenuShortcut(KeyEvent.VK_N));
      newMenuItem.setActionCommand("New");

      MenuItem openMenuItem = new MenuItem("Open");
      openMenuItem.setActionCommand("Open");

      MenuItem saveMenuItem = new MenuItem("Save");
      saveMenuItem.setActionCommand("Save");

      MenuItem exitMenuItem = new MenuItem("Exit");
      exitMenuItem.setActionCommand("Exit");

      MenuItem cutMenuItem = new MenuItem("Cut");
      cutMenuItem.setActionCommand("Cut");

      MenuItem copyMenuItem = new MenuItem("Copy");
      copyMenuItem.setActionCommand("Copy");

      MenuItem pasteMenuItem = new MenuItem("Paste");
      pasteMenuItem.setActionCommand("Paste");
   
      MenuItemListener menuItemListener = new MenuItemListener();

      newMenuItem.addActionListener(menuItemListener);
      openMenuItem.addActionListener(menuItemListener);
      saveMenuItem.addActionListener(menuItemListener);
      exitMenuItem.addActionListener(menuItemListener);
      cutMenuItem.addActionListener(menuItemListener);
      copyMenuItem.addActionListener(menuItemListener);
      pasteMenuItem.addActionListener(menuItemListener);

      final CheckboxMenuItem showWindowMenu = 
         new CheckboxMenuItem("Show About", true);
      showWindowMenu.addItemListener(new ItemListener() {
         public void itemStateChanged(ItemEvent e) {
            if(showWindowMenu.getState()){
               menuBar.add(aboutMenu);
            }else{
               menuBar.remove(aboutMenu);
            }
         }
      });

      //add menu items to menus
      fileMenu.add(newMenuItem);
      fileMenu.add(openMenuItem);
      fileMenu.add(saveMenuItem);
      fileMenu.addSeparator();
      fileMenu.add(showWindowMenu);
      fileMenu.addSeparator();
      fileMenu.add(exitMenuItem);

      editMenu.add(cutMenuItem);
      editMenu.add(copyMenuItem);
      editMenu.add(pasteMenuItem);

      //add menu to menubar
      menuBar.add(fileMenu);
      menuBar.add(editMenu);
      menuBar.add(aboutMenu);

      //add menubar to the frame
      mainFrame.setMenuBar(menuBar);
      mainFrame.setVisible(true);  
   }

   class MenuItemListener implements ActionListener {
      public void actionPerformed(ActionEvent e) {            
         statusLabel.setText(e.getActionCommand() 
            + " MenuItem clicked.");
      }    
   }
}

Compile the program using the command prompt. Go to D:/ > AWT and type the following command.

D:\AWT>javac com\adglob\gui\AWTMenuDemo.java

If no error comes that means compilation is successful. Run the program using following command.

D:\AWT>java com.adglob.gui.AWTMenuDemo

Verify the following output. (Click on File Menu.)

Menu class

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