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AWT MenuItem Class

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MenuItem

Introduction

The MenuBar class represents the actual item in a menu. All items in a menu should derive from class MenuItem, or one of its subclasses. By default, it embodies a simple labeled menu item.

Class declaration

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

public class MenuItem
   extends MenuComponent
      implements Accessible

Class constructors

S.N.Constructor & Description
1MenuItem()Constructs a new MenuItem with an empty label and no keyboard shortcut.
2MenuItem(String label)Constructs a new MenuItem with the specified label and no keyboard shortcut.
3MenuItem(String label, MenuShortcut s)Create a menu item with an associated keyboard shortcut.

Class methods

S.N.Method & Description
1void addActionListener(ActionListener l)Adds the specified action listener to receive action events from this menu item.
2void addNotify()Creates the menu item’s peer.
3void deleteShortcut()Delete any MenuShortcut object associated with this menu item.
4void disable()Deprecated. As of JDK version 1.1, replaced by setEnabled(boolean).
5protected void disableEvents(long eventsToDisable)Disables event delivery to this menu item for events defined by the specified event mask parameter.
6void enable()Deprecated. As of JDK version 1.1, replaced by setEnabled(boolean).
7void enable(boolean b)Deprecated. As of JDK version 1.1, replaced by setEnabled(boolean).
8protected void enableEvents(long eventsToEnable)Enables event delivery to this menu item for events to be defined by the specified event mask parameter.
9AccessibleContext getAccessibleContext()Gets the AccessibleContext associated with this MenuItem.
10String getActionCommand()Gets the command name of the action event that is fired by this menu item.
11ActionListener[] getActionListeners()Returns an array of all the action listeners registered on this menu item.
12String getLabel()Gets the label for this menu item.
13EventListener[] getListeners(Class listenerType)Returns an array of all the objects currently registered as FooListeners upon this MenuItem.
14MenuShortcut getShortcut()Get the MenuShortcut object associated with this menu item.
15boolean isEnabled()Checks whether this menu item is enabled.
16String paramString()Returns a string representing the state of this MenuItem.
17protected void processActionEvent(ActionEvent e)Processes action events occurring on this menu item, by dispatching them to any registered ActionListener objects.
18protected void processEvent(AWTEvent e)Processes events on this menu item.
19void removeActionListener(ActionListener l)Removes the specified action listener so it no longer receives action events from this menu item.
20void setActionCommand(String command)Sets the command name of the action event that is fired by this menu item.
21void setEnabled(boolean b)Sets whether or not this menu item can be chosen.
22void setLabel(String label)Sets the label for this menu item to the specified label.
23void setShortcut(MenuShortcut s)Set the MenuShortcut object associated with this menu item.

Methods inherited

This class inherits methods from the following classes:

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

MenuItem 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. Select any menu item.)

MenuItem

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