/*
* @(#)MenuBar.java 1.61 06/10/10
*
* Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*
*/
package java.awt;
import java.util.Vector;
import java.util.Enumeration;
import sun.awt.peer.MenuBarPeer;
import sun.awt.PeerBasedToolkit;
import java.awt.event.KeyEvent;
/**
* The <code>MenuBar</code> class encapsulates the platform's
* concept of a menu bar bound to a frame. In order to associate
* the menu bar with a <code>Frame</code> object, call the
* frame's <code>setMenuBar</code> method.
* <p>
* <A NAME="mbexample"></A><!-- target for cross references -->
* This is what a menu bar might look like:
* <p>
* <img src="doc-files/MenuBar-1.gif"
* ALIGN=center HSPACE=10 VSPACE=7>
* <p>
* A menu bar handles keyboard shortcuts for menu items, passing them
* along to its child menus.
* (Keyboard shortcuts, which are optional, provide the user with
* an alternative to the mouse for invoking a menu item and the
* action that is associated with it.)
* Each menu item can maintain an instance of <code>MenuShortcut</code>.
* The <code>MenuBar</code> class defines several methods,
* {@link MenuBar#shortcuts} and
* {@link MenuBar#getShortcutMenuItem}
* that retrieve information about the shortcuts a given
* menu bar is managing.
*
* @version 1.56, 08/19/02
* @author Sami Shaio
* @see java.awt.Frame
* @see java.awt.Frame#setMenuBar(java.awt.MenuBar)
* @see java.awt.Menu
* @see java.awt.MenuItem
* @see java.awt.MenuShortcut
* @since JDK1.0
*/
public class MenuBar extends MenuComponent implements MenuContainer {
/**
* This field represents a vector of the
* actual menus that will be part of the MenuBar.
*
* @serial
* @see countMenus()
*/
Vector menus = new Vector();
/**
* This menu is a special menu dedicated to
* help. The one thing to note about this menu
* is that on some platforms it appears at the
* right edge of the menubar.
*
* @serial
* @see getHelpMenu()
* @see setHelpMenu()
*/
Menu helpMenu;
private static final String base = "menubar";
private static int nameCounter = 0;
/*
* JDK 1.1 serialVersionUID
*/
private static final long serialVersionUID = -4930327919388951260L;
/**
* Creates a new menu bar.
*/
public MenuBar() {}
/**
* Construct a name for this MenuComponent. Called by getName() when
* the name is null.
*/
String constructComponentName() {
return base + nameCounter++;
}
/**
* Creates the menu bar's peer. The peer allows us to change the
* appearance of the menu bar without changing any of the menu bar's
* functionality.
*/
public void addNotify() {
synchronized (getTreeLock()) {
if (peer == null)
peer = ((PeerBasedToolkit) Toolkit.getDefaultToolkit()).createMenuBar(this);
int nmenus = getMenuCount();
for (int i = 0; i < nmenus; i++) {
getMenu(i).addNotify();
}
}
}
/**
* Removes the menu bar's peer. The peer allows us to change the
* appearance of the menu bar without changing any of the menu bar's
* functionality.
*/
public void removeNotify() {
synchronized (getTreeLock()) {
int nmenus = getMenuCount();
for (int i = 0; i < nmenus; i++) {
getMenu(i).removeNotify();
}
super.removeNotify();
}
}
/**
* Gets the help menu on the menu bar.
* @return the help menu on this menu bar.
*/
public Menu getHelpMenu() {
return helpMenu;
}
/**
* Sets the specified menu to be this menu bar's help menu.
* If this menu bar has an existing help menu, the old help menu is
* removed from the menu bar, and replaced with the specified menu.
* @param m the menu to be set as the help menu
*/
public void setHelpMenu(Menu m) {
synchronized (getTreeLock()) {
if (helpMenu == m) {
return;
}
if (helpMenu != null) {
remove(helpMenu);
}
if (m.parent != this) {
add(m);
}
helpMenu = m;
if (m != null) {
m.isHelpMenu = true;
m.parent = this;
MenuBarPeer peer = (MenuBarPeer) this.peer;
if (peer != null) {
if (m.peer == null) {
m.addNotify();
}
peer.addHelpMenu(m);
}
}
}
}
/**
* Adds the specified menu to the menu bar.
* @param m the menu to be added.
* @return the menu added.
* @see java.awt.MenuBar#remove(int)
* @see java.awt.MenuBar#remove(java.awt.MenuComponent)
* @since JDK1.0
*/
public Menu add(Menu m) {
synchronized (getTreeLock()) {
if (m.parent != null) {
m.parent.remove(m);
}
menus.addElement(m);
m.parent = this;
MenuBarPeer peer = (MenuBarPeer) this.peer;
if (peer != null) {
if (m.peer == null) {
m.addNotify();
}
peer.addMenu(m);
}
return m;
}
}
/**
* Removes the menu located at the specified
* index from this menu bar.
* @param index the position of the menu to be removed.
* @see java.awt.MenuBar#add(java.awt.Menu)
*/
public void remove(int index) {
synchronized (getTreeLock()) {
MenuBarPeer peer = (MenuBarPeer) this.peer;
if (peer != null) {
Menu m = getMenu(index);
m.removeNotify();
m.parent = null;
peer.delMenu(index);
}
menus.removeElementAt(index);
}
}
/**
* Removes the specified menu component from this menu bar.
* @param m the menu component to be removed.
* @see java.awt.MenuBar#add(java.awt.Menu)
*/
public void remove(MenuComponent m) {
synchronized (getTreeLock()) {
int index = menus.indexOf(m);
if (index >= 0) {
remove(index);
}
}
}
/**
* Gets the number of menus on the menu bar.
* @return the number of menus on the menu bar.
* @since JDK1.1
*/
public int getMenuCount() {
return countMenus();
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getMenuCount()</code>.
*/
public int countMenus() {
return menus.size();
}
/**
* Gets the specified menu.
* @param i the index position of the menu to be returned.
* @return the menu at the specified index of this menu bar.
*/
public Menu getMenu(int i) {
return (Menu) menus.elementAt(i);
}
/**
* Gets an enumeration of all menu shortcuts this menu bar
* is managing.
* @return an enumeration of menu shortcuts that this
* menu bar is managing.
* @see java.awt.MenuShortcut
* @since JDK1.1
*/
public synchronized Enumeration shortcuts() {
Vector shortcuts = new Vector();
int nmenus = getMenuCount();
for (int i = 0; i < nmenus; i++) {
Enumeration e = getMenu(i).shortcuts();
while (e.hasMoreElements()) {
shortcuts.addElement(e.nextElement());
}
}
return shortcuts.elements();
}
/**
* Gets the instance of <code>MenuItem</code> associated
* with the specified <code>MenuShortcut</code> object,
* or <code>null</code> if none of the menu items being managed
* by this menu bar is associated with the specified menu
* shortcut.
* @param s the specified menu shortcut.
* @see java.awt.MenuItem
* @see java.awt.MenuShortcut
* @since JDK1.1
*/
public MenuItem getShortcutMenuItem(MenuShortcut s) {
int nmenus = getMenuCount();
for (int i = 0; i < nmenus; i++) {
MenuItem mi = getMenu(i).getShortcutMenuItem(s);
if (mi != null) {
return mi;
}
}
return null; // MenuShortcut wasn't found
}
/*
* Post an ACTION_EVENT to the target of the MenuPeer
* associated with the specified keyboard event (on
* keydown). Returns true if there is an associated
* keyboard event.
*/
boolean handleShortcut(KeyEvent e) {
// Is it a key event?
int id = e.getID();
if (id != KeyEvent.KEY_PRESSED && id != KeyEvent.KEY_RELEASED) {
return false;
}
// Is the accelerator modifier key pressed?
int accelKey = Toolkit.getDefaultToolkit().getMenuShortcutKeyMask();
if ((e.getModifiers() & accelKey) == 0) {
return false;
}
// Pass MenuShortcut on to child menus.
int nmenus = getMenuCount();
for (int i = 0; i < nmenus; i++) {
Menu m = getMenu(i);
if (m.handleShortcut(e)) {
return true;
}
}
return false;
}
/**
* Deletes the specified menu shortcut.
* @param s the menu shortcut to delete.
* @since JDK1.1
*/
public void deleteShortcut(MenuShortcut s) {
int nmenus = getMenuCount();
for (int i = 0; i < nmenus; i++) {
getMenu(i).deleteShortcut(s);
}
}
/* Serialization support. Restore the (transient) parent
* fields of Menubar menus here.
*/
private int menuBarSerializedDataVersion = 1;
/**
* Writes default serializable fields to stream. Writes
* a list of serializable ItemListener(s) as optional data.
* The non-serializable ItemListner(s) are detected and
* no attempt is made to serialize them.
*
* @serialData Null terminated sequence of 0 or more pairs.
* The pair consists of a String and Object.
* The String indicates the type of object and
* is one of the following :
* itemListenerK indicating and ItemListener object.
*
* @see AWTEventMulticaster.save(ObjectOutputStream, String, EventListener)
* @see java.awt.Component.itemListenerK
*/
private void writeObject(java.io.ObjectOutputStream s)
throws java.lang.ClassNotFoundException,
java.io.IOException {
s.defaultWriteObject();
}
/**
* Read the ObjectInputStream and if it isnt null
* add a listener to receive item events fired
* by the MenuBar.
* Unrecognised keys or values will be Ignored.
*
* @see removeActionListener()
* @see addActionListener()
*/
private void readObject(java.io.ObjectInputStream s) throws java.lang.ClassNotFoundException, java.io.IOException {
s.defaultReadObject();
for (int i = 0; i < menus.size(); i++) {
Menu m = (Menu) menus.elementAt(i);
m.parent = this;
}
}
}