Java Tutorial/Swing/JPopupMenu

Adding action listener to popup menuitem

   <source lang="java">

import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JMenuItem; import javax.swing.JPopupMenu; // Define ActionListener class PopupActionListener implements ActionListener {

 public void actionPerformed(ActionEvent actionEvent) {
   System.out.println("Selected: " + actionEvent.getActionCommand());
 }

} public class JPopupMenuItemActionListener {

 public static void main(final String args[]) {
   JFrame frame = new JFrame("PopupSample Example");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   // Create popup menu, attach popup menu listener
   JPopupMenu popupMenu = new JPopupMenu("Title");
   ActionListener actionListener = new PopupActionListener();
   // Cut
   JMenuItem cutMenuItem = new JMenuItem("Cut");
   popupMenu.add(cutMenuItem);
   // Copy
   JMenuItem copyMenuItem = new JMenuItem("Copy");
   copyMenuItem.addActionListener(actionListener);
   popupMenu.add(copyMenuItem);
   // Paste
   JMenuItem pasteMenuItem = new JMenuItem("Paste");
   pasteMenuItem.addActionListener(actionListener);
   pasteMenuItem.setEnabled(false);
   popupMenu.add(pasteMenuItem);
   // Separator
   popupMenu.addSeparator();
   // Find
   JMenuItem findMenuItem = new JMenuItem("Find");
   findMenuItem.addActionListener(actionListener);
   popupMenu.add(findMenuItem);
   JButton label = new JButton();
   frame.add(label);
   label.setComponentPopupMenu(popupMenu);
   frame.setSize(350, 250);
   frame.setVisible(true);
 }

}</source>

Creating a Popup Menu

   <source lang="java">

import java.awt.event.MouseAdapter; import java.awt.event.MouseEvent; import javax.swing.JButton; import javax.swing.JMenuItem; import javax.swing.JPopupMenu; public class Main {

 public static void main(String[] argv) throws Exception {
   final JPopupMenu menu = new JPopupMenu();
   JMenuItem item = new JMenuItem("Item Label");

// item.addActionListener(actionListener);

   menu.add(item);
   JButton component = new JButton("button");
   component.addMouseListener(new MouseAdapter() {
     public void mousePressed(MouseEvent evt) {
       if (evt.isPopupTrigger()) {
         menu.show(evt.getComponent(), evt.getX(), evt.getY());
       }
     }
     public void mouseReleased(MouseEvent evt) {
       if (evt.isPopupTrigger()) {
         menu.show(evt.getComponent(), evt.getX(), evt.getY());
       }
     }
   });
 }

}</source>

Creating a Popup Menu with Nested Menus

   <source lang="java">

import javax.swing.JMenu; import javax.swing.JPopupMenu; public class Main {

 public static void main(String[] argv) throws Exception {
   final JPopupMenu popupMenu = new JPopupMenu();
   JMenu submenu = new JMenu("SubMenu1");
   submenu.add("asdf");
   submenu.add("asdf");
   // Add submenu to popup menu
   popupMenu.add(submenu);
 }

}</source>

Customizing JPopupMenu Look and Feel

Property StringObject TypePopupMenu.actionMapActionMapPopupMenu.backgroundColorPopupMenu.borderBorderPopupMenu.consumeEventOnCloseBooleanPopupMenu.fontFontPopupMenu.foregroundColorPopupMenu.popupSoundStringPopupMenu.selectedWindowInputMapBindingsObject[ ]PopupMenu.selectedWindowInputMapBindings.RightToLeftObject[ ]PopupMenuSeparatorUIStringPopupMenuUIString

Force the popup menu of a JMenu to be heavyweight:

   <source lang="java">

import javax.swing.JMenu; import javax.swing.JMenuItem; public class Main {

 public static void main(String[] argv) throws Exception {
   JMenu menu = new JMenu("Menu Label");
   menu.add(new JMenuItem("Item Label"));
   boolean lwPopup = menu.getPopupMenu().isLightWeightPopupEnabled(); // true
   menu.getPopupMenu().setLightWeightPopupEnabled(false);
 }

}</source>

Forcing a Popup Menu to Be a Heavyweight Component

   <source lang="java">

import javax.swing.JPopupMenu; public class Main {

 public static void main(String[] argv) throws Exception {
   JPopupMenu popupMenu = new JPopupMenu();
   boolean lwPopup = popupMenu.isLightWeightPopupEnabled(); // true
   popupMenu.setLightWeightPopupEnabled(false);
 }

}</source>

JPopupMenu: the container for pop-up menu components

Adding Menu Items to a JPopupMenu

   <source lang="java">

public JMenuItem add(JMenuItem menuItem); public JMenuItem add(String label); public JMenuItem add(Action action); public void addSeparator();</source>

To display JPopupMenu on an AWT component

If you need to enable the display of a Panel (an AWT component), you can configure it at the individual JPopupMenu level or for your entire applet or application. At the individual pop-up level, just set the lightWeightPopupEnabled property to false.

The setInheritsPopupMenu() method accepts a boolean argument. When true, and no component pop-up menu has been directly set for the component, the parent container will be explored for a pop-up.

At the system level, this is done as follows:

   <source lang="java">

// From now on, all JPopupMenus will be heavyweight JPopupMenu.setDefaultLightWeightPopupEnabled(false);</source>

Using PopupMenuListener

   <source lang="java">

import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JMenuItem; import javax.swing.JPopupMenu; import javax.swing.event.PopupMenuEvent; import javax.swing.event.PopupMenuListener; // Define PopupMenuListener class MyPopupMenuListener implements PopupMenuListener {

 public void popupMenuCanceled(PopupMenuEvent popupMenuEvent) {
   System.out.println("Canceled");
 }
 public void popupMenuWillBecomeInvisible(PopupMenuEvent popupMenuEvent) {
   System.out.println("Becoming Invisible");
 }
 public void popupMenuWillBecomeVisible(PopupMenuEvent popupMenuEvent) {
   System.out.println("Becoming Visible");
 }

} public class PopupMenuListenerDemo {

 public static void main(final String args[]) {
   JFrame frame = new JFrame("PopupSample Example");
   frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   // Create popup menu, attach popup menu listener
   JPopupMenu popupMenu = new JPopupMenu("Title");
   PopupMenuListener popupMenuListener = new MyPopupMenuListener();
   popupMenu.addPopupMenuListener(popupMenuListener);
   // Cut
   JMenuItem cutMenuItem = new JMenuItem("Cut");
   popupMenu.add(cutMenuItem);
   // Copy
   JMenuItem copyMenuItem = new JMenuItem("Copy");
   popupMenu.add(copyMenuItem);
   // Paste
   JMenuItem pasteMenuItem = new JMenuItem("Paste");
   pasteMenuItem.setEnabled(false);
   popupMenu.add(pasteMenuItem);
   // Separator
   popupMenu.addSeparator();
   // Find
   JMenuItem findMenuItem = new JMenuItem("Find");
   popupMenu.add(findMenuItem);
   JButton label = new JButton();
   frame.add(label);
   label.setComponentPopupMenu(popupMenu);
   frame.setSize(350, 250);
   frame.setVisible(true);
 }

}</source>