SWING - JMenu Class
Introduction
The Menu class represents pull-down menu component which is deployed from a menu bar.
Class declaration
Following is the declaration for javax.swing.JMenu class:
public class JMenu extends JMenuItem implements Accessible, MenuElement
Field
Following are the fields for java.awt.Component class:
protected JMenu.WinListener popupListener -- The window-closing listener for the popup.
Class constructors
S.N. | Constructor & Description |
---|---|
1 | JMenu() Constructs a new JMenu with no text. |
2 | JMenu(Action a) Constructs a menu whose properties are taken from the Action supplied. |
3 | JMenu(String s) Constructs a new JMenu with the supplied string as its text. |
4 | JMenu(String s, boolean b) Constructs a new JMenu with the supplied string as its text and specified as a tear-off menu or not. |
Class methods
S.N. | Method & Description |
---|---|
1 | JMenuItem add(Action a) Creates a new menu item attached to the specified Action object and appends it to the end of this menu. |
2 | Component add(Component c) Appends a component to the end of this menu. |
3 | Component add(Component c, int index) Adds the specified component to this container at the given position. |
4 | JMenuItem add(JMenuItem menuItem) Appends a menu item to the end of this menu. |
5 | JMenuItem add(String s) Creates a new menu item with the specified text and appends it to the end of this menu. |
6 | void addMenuListener(MenuListener l)
Adds a listener for menu events. |
7 | void addSeparator() Appends a new separator to the end of the menu. |
8 | void applyComponentOrientation(ComponentOrientation o) Sets the ComponentOrientation property of this menu and all components contained within it. |
9 | protected PropertyChangeListener createActionChangeListener(JMenuItem b) Returns a properly configured PropertyChangeListener which updates the control as changes to the Action occur. |
10 | protected JMenuItem createActionComponent(Action a) Factory method which creates the JMenuItem for Actions added to the JMenu. |
11 | protected JMenu.WinListener createWinListener(JPopupMenu p) Creates a window-closing listener for the popup. |
12 | void doClick(int pressTime) Programmatically performs a "click". |
13 | protected void fireMenuCanceled() Notifies all listeners that have registered interest for notification on this event type. |
14 | protected void fireMenuDeselected() Notifies all listeners that have registered interest for notification on this event type. |
15 | protected void fireMenuSelected() Notifies all listeners that have registered interest for notification on this event type. |
16 | AccessibleContext getAccessibleContext() Gets the AccessibleContext associated with this JMenu. |
17 | Component getComponent() Returns the java.awt.Component used to paint this MenuElement. |
18 | int getDelay() Returns the suggested delay, in milliseconds, before submenus are popped up or down. |
19 | JMenuItem getItem(int pos) Returns the JMenuItem at the specified position. |
20 | int getItemCount() Returns the number of items on the menu, including separators. |
21 | Component getMenuComponent(int n) Returns the component at position n. |
22 | int getMenuComponentCount() Returns the number of components on the menu. |
23 | Component[] getMenuComponents() Returns an array of Components of the menu's subcomponents. |
24 | MenuListener[]getMenuListeners() Returns an array of all the MenuListeners added to this JMenu with addMenuListener(). |
25 | JPopupMenu getPopupMenu() Returns the popupmenu associated with this menu. |
26 | protected Point getPopupMenuOrigin() Computes the origin for the JMenu's popup menu. |
27 | MenuElement[] getSubElements() Returns an array of MenuElements containing the submenu for this menu component. |
28 | String getUIClassID() Returns the name of the L&F class that renders this component. |
29 | JMenuItem insert(Action a, int pos) Inserts a new menu item attached to the specified Action object at a given position. |
30 | JMenuItem insert(JMenuItem mi, int pos) Inserts the specified JMenuitem at a given position. |
31 | void insert(String s, int pos) Inserts a new menu item with the specified text at a given position. |
32 | void insertSeparator(int index) Inserts a separator at the specified position. |
33 | boolean isMenuComponent(Component c) Returns true if the specified component exists in the submenu hierarchy. |
34 | boolean isPopupMenuVisible() Returns true if the menu's popup window is visible. |
35 | boolean isSelected() Returns true if the menu is currently selected (highlighted). |
36 | boolean isTearOff() Returns true if the menu can be torn off. |
37 | boolean isTopLevelMenu() Returns true if the menu is a 'top-level menu', that is, if it is the direct child of a menubar. |
38 | void menuSelectionChanged(boolean isIncluded) Messaged when the menubar selection changes to activate or deactivate this menu. |
39 | protected String paramString() Returns a string representation of this JMenu. |
40 | protected void processKeyEvent(KeyEvent evt) Processes key stroke events such as mnemonics and accelerators. |
41 | void remove(Component c) Removes the component c from this menu. |
42 | void remove(int pos) Removes the menu item at the specified index from this menu. |
43 | void remove(JMenuItem item) Removes the specified menu item from this menu. |
44 | void removeAll() Removes all menu items from this menu. |
45 | void removeMenuListener(MenuListener l) Removes a listener for menu events. |
46 | void setAccelerator(KeyStroke keyStroke) setAccelerator is not defined for JMenu. |
47 | void setComponentOrientation(ComponentOrientation o) Sets the language-sensitive orientation that is to be used to order the elements or text within this component. |
48 | void setDelay(int d) Sets the suggested delay before the menu's PopupMenu is popped up or down. |
49 | void setMenuLocation(int x, int y) Sets the location of the popup component. |
50 | void setModel(ButtonModel newModel) Sets the data model for the "menu button" -- the label that the user clicks to open or close the menu. |
51 | void setPopupMenuVisible(boolean b) Sets the visibility of the menu's popup. |
52 | void setSelected(boolean b) Sets the selection status of the menu. |
53 | void updateUI() Resets the UI property with a value from the current look and feel. |
Methods inherited
This class inherits methods from the following classes:
javax.swing.JAbstractButton
javax.swing.JComponent
java.awt.Container
java.awt.Component
java.lang.Object
JMenu Example
Create the following java program using any editor of your choice in say D:/ > SWING > com > tutorialspoint > gui >
SwingMenuDemo.javapackage com.tutorialspoint.gui; import java.awt.*; import java.awt.event.*; public class SwingMenuDemo { private JFrame mainFrame; private JLabel headerLabel; private JLabel statusLabel; private JPanel controlPanel; public SwingMenuDemo(){ prepareGUI(); } public static void main(String[] args){ SwingMenuDemo swingMenuDemo = new SwingMenuDemo(); swingMenuDemo.showMenuDemo(); } private void prepareGUI(){ mainFrame = new JFrame("Java SWING Examples"); mainFrame.setSize(400,400); mainFrame.setLayout(new GridLayout(3, 1)); headerLabel = new JLabel("",JLabel.CENTER ); statusLabel = new JLabel("",JLabel.CENTER); statusLabel.setSize(350,100); mainFrame.addWindowListener(new WindowAdapter() { public void windowClosing(WindowEvent windowEvent){ System.exit(0); } }); controlPanel = new JPanel(); controlPanel.setLayout(new FlowLayout()); mainFrame.add(headerLabel); mainFrame.add(controlPanel); mainFrame.add(statusLabel); mainFrame.setVisible(true); } private void showMenuDemo(){ //create a menu bar final JMenuBar menuBar = new JMenuBar(); //create menus JMenu fileMenu = new JMenu("File"); JMenu editMenu = new JMenu("Edit"); final JMenu aboutMenu = new JMenu("About"); final JMenu linkMenu = new JMenu("Links"); //create menu items JMenuItem newMenuItem = new JMenuItem("New"); newMenuItem.setMnemonic(KeyEvent.VK_N); newMenuItem.setActionCommand("New"); JMenuItem openMenuItem = new JMenuItem("Open"); openMenuItem.setActionCommand("Open"); JMenuItem saveMenuItem = new JMenuItem("Save"); saveMenuItem.setActionCommand("Save"); JMenuItem exitMenuItem = new JMenuItem("Exit"); exitMenuItem.setActionCommand("Exit"); JMenuItem cutMenuItem = new JMenuItem("Cut"); cutMenuItem.setActionCommand("Cut"); JMenuItem copyMenuItem = new JMenuItem("Copy"); copyMenuItem.setActionCommand("Copy"); JMenuItem pasteMenuItem = new JMenuItem("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 JCheckBoxMenuItem showWindowMenu = new JCheckBoxMenuItem("Show About", true); showWindowMenu.addItemListener(new ItemListener() { public void itemStateChanged(ItemEvent e) { if(showWindowMenu.getState()){ menuBar.add(aboutMenu); }else{ menuBar.remove(aboutMenu); } } }); final JRadioButtonMenuItem showLinksMenu = new JRadioButtonMenuItem("Show Links", true); showLinksMenu.addItemListener(new ItemListener() { public void itemStateChanged(ItemEvent e) { if(menuBar.getMenu(3)!= null){ menuBar.remove(linkMenu); mainFrame.repaint(); }else{ menuBar.add(linkMenu); mainFrame.repaint(); } } }); //add menu items to menus fileMenu.add(newMenuItem); fileMenu.add(openMenuItem); fileMenu.add(saveMenuItem); fileMenu.addSeparator(); fileMenu.add(showWindowMenu); fileMenu.addSeparator(); fileMenu.add(showLinksMenu); 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); menuBar.add(linkMenu); //add menubar to the frame mainFrame.setJMenuBar(menuBar); mainFrame.setVisible(true); } class MenuItemListener implements ActionListener { public void actionPerformed(ActionEvent e) { statusLabel.setText(e.getActionCommand() + " JMenuItem clicked."); } } }
Compile the program using command prompt. Go to D:/ > SWING and type the following command.
D:\SWING>javac com\tutorialspoint\gui\SwingMenuDemo.java
If no error comes that means compilation is successful. Run the program using following command.
D:\SWING>java com.tutorialspoint.gui.SwingMenuDemo
Verify the following output. (Click on File Menu.)
![SWING JMenu](/swing/images/swing_jmenu.jpg)