Java Tutorial/Swing/JMenuItem

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Adding Drop-Down Menus

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;
public class AddingDropDownMenus 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 AddingDropDownMenus() {
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setJMenuBar(menuBar);
    JMenu fileMenu = new JMenu("File");
    JMenu elementMenu = new JMenu("Elements");
    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);
  }
  public static void main(String[] a) {
    AddingDropDownMenus window = new AddingDropDownMenus(); 
    window.setBounds(30, 30, 300, 300); // Size
    window.setVisible(true);
  }
}





Adding Mnemonic and Accelerator to Menuitem

A menu accelerator activates a menu item when it is not visible.



import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.KeyStroke;
public class JMenuItemKeyStroke {
  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->Cut, T - Mnemonic, CTRL-X - Accelerator
    JMenuItem cutMenuItem = new JMenuItem("Cut", KeyEvent.VK_T);
    KeyStroke ctrlXKeyStroke = KeyStroke.getKeyStroke("control X");
    cutMenuItem.setAccelerator(ctrlXKeyStroke);
    fileMenu.add(cutMenuItem);
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}





Creating a Menu Item That Listens for Changes to Its Selection Status

import javax.swing.JMenuItem;
public class Main {
  public static void main(String[] argv) throws Exception {
    JMenuItem item = new JMenuItem("Label") {
      public void menuSelectionChanged(boolean isSelected) {
        super.menuSelectionChanged(isSelected);
        if (isSelected) {
          System.out.println("The menu item is selected"); 
        } else {
          System.out.println("The menu item is no longer selected"); 
        }
      }
    };
  }
}





Creating an About Menu Item

import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
public class FramewithAboutMenu extends JFrame {
  public FramewithAboutMenu(String title) {
    JMenuBar menuBar = new JMenuBar();
    setTitle(title);
    setJMenuBar(menuBar);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    JMenu fileMenu = new JMenu("File");
    JMenu elementMenu = new JMenu("Elements");
    JMenu helpMenu = new JMenu("Help");
    fileMenu.setMnemonic("F");
    elementMenu.setMnemonic("E");
    helpMenu.setMnemonic("H");
    JMenuItem aboutItem = new JMenuItem("About");
    helpMenu.add(aboutItem);
    menuBar.add(helpMenu);
  }
  public static void main(String[] a) {
    FramewithAboutMenu window = new FramewithAboutMenu("Sketcher");
    window.setBounds(30, 30, 300, 300);
    window.setVisible(true);
  }
}





Creating JMenuItem Components

public JMenuItem()
JMenuItem jMenuItem = new JMenuItem();
public JMenuItem(Icon icon)
Icon atIcon = new ImageIcon("at.gif");
JMenuItem jMenuItem = new JMenuItem(atIcon);
public JMenuItem(String text)
JMenuItem jMenuItem = new JMenuItem("Cut");
public JMenuItem(String text, Icon icon)
Icon atIcon = new ImageIcon("at.gif");
JMenuItem jMenuItem = new JMenuItem("Options", atIcon);
public JMenuItem(String text, int mnemonic)
JMenuItem jMenuItem = new JMenuItem("Cut", KeyEvent.VK_T);
public JMenuItem(Action action)
Action action = ...;
JMenuItem jMenuItem = new JMenuItem(action);





Creating Menuitem from Action class

The mnemonic for a menu item usually appears underlined within the text label for the menu



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) {
        JOptionPane.showMessageDialog(parentComponent, "About Swing", "About Box V2.0",
            JOptionPane.INFORMATION_MESSAGE);
  }
}
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);
  }
}





Customizing JMenuItem Look and Feel

Property StringObject TypeMenuItem.acceleratorDelimiterStringMenuItem.acceleratorFontFontMenuItem.acceleratorForegroundColorMenuItem.acceleratorSelectionForegroundColorMenuItem.actionMapActionMapMenuItem.arrowIconIconMenuItem.backgroundColorMenuItem.borderBorderMenuItem.borderPaintedBooleanMenuItem.checkIconIconMenuItem.rumandSoundStringMenuItem.disabledForegroundColorMenuItem.fontFontMenuItem.foregroundColorMenuItem.marginInsetsMenuItem.opaqueBooleanMenuItem.selectionBackgroundColorMenuItem.selectionForegroundColorMenuItem.textIconGapIntegerMenuItemUIString


Disable Menuitem

import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.KeyStroke;
public class JMenuItemDisabled {
  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->Paste, P - Mnemonic, CTRL-V - Accelerator, Disabled
    JMenuItem pasteMenuItem = new JMenuItem("Paste", KeyEvent.VK_P);
    KeyStroke ctrlVKeyStroke = KeyStroke.getKeyStroke("control V");
    pasteMenuItem.setAccelerator(ctrlVKeyStroke);
    pasteMenuItem.setEnabled(false);
    fileMenu.add(pasteMenuItem);
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}





Listening to JMenuItem Events with a MenuDragMouseListener

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.MenuDragMouseEvent;
import javax.swing.event.MenuDragMouseListener;
public class ContructMenuMenuDragMouseListener {
  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("asdf");
    fileMenu.add(newMenuItem);
    
    newMenuItem.addMenuDragMouseListener(new MenuDragMouseListener(){
      public void menuDragMouseEntered(MenuDragMouseEvent e) {
        System.out.println("menuDragMouseEntered");        
      }
      public void menuDragMouseExited(MenuDragMouseEvent e) {
       System.out.println("menuDragMouseExited");
        
      }
      public void menuDragMouseDragged(MenuDragMouseEvent e) {
        System.out.println("menuDragMouseDragged");
        
      }
      public void menuDragMouseReleased(MenuDragMouseEvent e) {
        System.out.println("menuDragMouseReleased");
        
      }});
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}





Listening to JMenuItem Events with a MenuKeyListener

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.MenuKeyEvent;
import javax.swing.event.MenuKeyListener;
public class ContructMenuMenuKeyListener {
  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("asdf");
    fileMenu.add(newMenuItem);
    
    newMenuItem.addMenuKeyListener(new MenuKeyListener(){
      public void menuKeyTyped(MenuKeyEvent e) {
       System.out.println("KeyTyped");
      }
      public void menuKeyPressed(MenuKeyEvent e) {
        System.out.println("KeyPressed");
      }
      public void menuKeyReleased(MenuKeyEvent e) {
        System.out.println("KeyReleased");
      }});
    
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}





Listening to JMenuItem Events with an ActionListener

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 e) {
    System.out.println("Selected: " + e.getActionCommand());
  }
}
public class ContructMenuActionListener {
  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");
    newMenuItem.addActionListener(new MenuActionListener());
    fileMenu.add(newMenuItem);
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}





Separating Menu Items in a Menu

import javax.swing.JMenu;
import javax.swing.JMenuItem;
import javax.swing.JSeparator;
public class Main {
  public static void main(String[] argv) throws Exception {
    JMenu menu = new JMenu("Menu Label");
    JMenuItem item1 = new JMenuItem("Item Label");
    menu.add(item1);
    // Add separator
    menu.add(new JSeparator());
    // Add another menu item
    JMenuItem item2 = new JMenuItem("Item Label");
    menu.add(item2);
  }
}





Using Function key as Accelerator

import java.awt.event.KeyEvent;
import javax.swing.JFrame;
import javax.swing.JMenu;
import javax.swing.JMenuBar;
import javax.swing.JMenuItem;
import javax.swing.KeyStroke;
public class JMenuItemAccelerator {
  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->Find, F - Mnemonic, F3 - Accelerator
    JMenuItem findMenuItem = new JMenuItem("Find", KeyEvent.VK_F);
    KeyStroke f3KeyStroke = KeyStroke.getKeyStroke("F3");
    findMenuItem.setAccelerator(f3KeyStroke);
    fileMenu.add(findMenuItem);
    frame.setJMenuBar(menuBar);
    frame.setSize(350, 250);
    frame.setVisible(true);
  }
}