/*
* @(#)Menu.java 1.59 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.MenuPeer;
import sun.awt.PeerBasedToolkit;
import java.awt.event.KeyEvent;
/**
* A <code>Menu</code> object is a pull-down menu component
* that is deployed from a menu bar.
* <p>
* A menu can optionally be a <i>tear-off</i> menu. A tear-off menu
* can be opened and dragged away from its parent menu bar or menu.
* It remains on the screen after the mouse button has been released.
* The mechanism for tearing off a menu is platform dependent, since
* the look and feel of the tear-off menu is determined by its peer.
* On platforms that do not support tear-off menus, the tear-off
* property is ignored.
* <p>
* Each item in a menu must belong to the <code>MenuItem</code>
* class. It can be an instance of <code>MenuItem</code>, a submenu
* (an instance of <code>Menu</code>), or a check box (an instance of
* <code>CheckboxMenuItem</code>).
*
* @version 1.55, 08/19/02
* @author Sami Shaio
* @see java.awt.MenuItem
* @see java.awt.MenuBar
* @see java.awt.MenuShortcut
* @see java.awt.CheckboxMenuItem
* @see java.awt.Frame
* @since JDK1.0
*/
public class Menu extends MenuItem implements MenuContainer {
/**
* A vector of the items that will be part of the Menu.
*
* @serial
* @see countItems()
*/
Vector items = new Vector();
/**
* This field indicates whether the menu has the
* tear of property or not. It will be set to
* <code>true</code> if the menu has the tear off
* property and it will be set to <code>false></code>
* if it does not.
* A torn off menu can be deleted by a user when
* it is no longer needed.
*
* @serial
* @see isTearOff()
*/
boolean tearOff;
/**
* This field will be set to <code>true</code>
* if the Menu in question is actually a help
* menu. Otherwise it will be set to <code>
* false</code>.
*
* @serial
*/
boolean isHelpMenu;
private static final String base = "menu";
private static int nameCounter = 0;
/*
* JDK 1.1 serialVersionUID
*/
private static final long serialVersionUID = -8809584163345499784L;
/**
* Constructs a new menu with an empty label. This menu is not
* a tear-off menu.
* @since JDK1.1
*/
public Menu() {
this("", false);
}
/**
* Constructs a new menu with the specified label. This menu is not
* a tear-off menu.
* @param label the menu's label in the menu bar, or in
* another menu of which this menu is a submenu.
*/
public Menu(String label) {
this(label, false);
}
/**
* Constructs a new menu with the specified label,
* indicating whether the menu can be torn off.
* <p>
* Tear-off functionality may not be supported by all
* implementations of AWT. If a particular implementation doesn't
* support tear-off menus, this value is silently ignored.
* @param label the menu's label in the menu bar, or in
* another menu of which this menu is a submenu.
* @param tearOff if <code>true</code>, the menu
* is a tear-off menu.
* @since JDK1.0.
*/
public Menu(String label, boolean tearOff) {
super(label);
checkPopup();
this.tearOff = tearOff;
}
/**
* Construct a name for this MenuComponent. Called by getName() when
* the name is null.
*/
String constructComponentName() {
return base + nameCounter++;
}
private void checkPopup() {}
private void checkNonCascading(MenuItem mi) {}
/**
* Creates the menu's peer. The peer allows us to modify the
* appearance of the menu without changing its functionality.
*/
public void addNotify() {
synchronized (getTreeLock()) {
if (peer == null) {
peer = ((PeerBasedToolkit) Toolkit.getDefaultToolkit()).createMenu(this);
}
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
MenuItem mi = getItem(i);
mi.parent = this;
mi.addNotify();
}
}
}
/**
* Removes the menu's peer. The peer allows us to modify the appearance
* of the menu without changing its functionality.
*/
public void removeNotify() {
synchronized (getTreeLock()) {
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
getItem(i).removeNotify();
}
super.removeNotify();
}
}
/**
* Indicates whether this menu is a tear-off menu.
* <p>
* Tear-off functionality may not be supported by all
* implementations of AWT. If a particular implementation doesn't
* support tear-off menus, this value is silently ignored.
* @return <code>true</code> if this is a tear-off menu;
* <code>false</code> otherwise.
*/
public boolean isTearOff() {
return tearOff;
}
/**
* Get the number of items in this menu.
* @return the number of items in this menu.
* @since JDK1.1
*/
public int getItemCount() {
return countItems();
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getItemCount()</code>.
*/
public int countItems() {
return items.size();
}
/**
* Gets the item located at the specified index of this menu.
* @param index the position of the item to be returned.
* @return the item located at the specified index.
*/
public MenuItem getItem(int index) {
return (MenuItem) items.elementAt(index);
}
/**
* Adds the specified menu item to this menu. If the
* menu item has been part of another menu, remove it
* from that menu.
* @param mi the menu item to be added.
* @return the menu item added.
* @see java.awt.Menu#insert(java.lang.String, int)
* @see java.awt.Menu#insert(java.awt.MenuItem, int)
*/
public MenuItem add(MenuItem mi) {
checkNonCascading(mi);
synchronized (getTreeLock()) {
if (mi.parent != null) {
mi.parent.remove(mi);
}
items.addElement(mi);
mi.parent = this;
MenuPeer peer = (MenuPeer) this.peer;
if (peer != null) {
mi.addNotify();
peer.addItem(mi);
}
return mi;
}
}
/**
* Adds an item with the specified label to this menu.
* @param label the text on the item.
* @see java.awt.Menu#insert(java.lang.String, int)
* @see java.awt.Menu#insert(java.awt.MenuItem, int)
*/
public void add(String label) {
add(new MenuItem(label));
}
/**
* Inserts a menu item into this menu
* at the specified position.
* @param menuitem the menu item to be inserted.
* @param index the position at which the menu
* item should be inserted.
* @see java.awt.Menu#add(java.lang.String)
* @see java.awt.Menu#add(java.awt.MenuItem)
* @exception IllegalArgumentException if the value of
* <code>index</code> is less than zero.
* @since JDK1.1
*/
public void insert(MenuItem menuitem, int index) {
synchronized (getTreeLock()) {
if (index < 0) {
throw new IllegalArgumentException("index less than zero.");
}
int nitems = getItemCount();
Vector tempItems = new Vector();
/* Remove the item at index, nitems-index times
storing them in a temporary vector in the
order they appear on the menu.
*/
for (int i = index; i < nitems; i++) {
tempItems.addElement(getItem(index));
remove(index);
}
add(menuitem);
/* Add the removed items back to the menu, they are
already in the correct order in the temp vector.
*/
for (int i = 0; i < tempItems.size(); i++) {
add((MenuItem) tempItems.elementAt(i));
}
}
}
/**
* Inserts a menu item with the specified label into this menu
* at the specified position.
* @param label the text on the item.
* @param index the position at which the menu item
* should be inserted.
* @see java.awt.Menu#add(java.lang.String)
* @see java.awt.Menu#add(java.awt.MenuItem)
* @since JDK1.1
*/
public void insert(String label, int index) {
insert(new MenuItem(label), index);
}
/**
* Adds a separator line, or a hypen, to the menu at the current position.
* @see java.awt.Menu#insertSeparator(int)
*/
public void addSeparator() {
add("-");
}
/**
* Inserts a separator at the specified position.
* @param index the position at which the
* menu separator should be inserted.
* @exception IllegalArgumentException if the value of
* <code>index</code> is less than 0.
* @see java.awt.Menu#addSeparator
* @since JDK1.1
*/
public void insertSeparator(int index) {
synchronized (getTreeLock()) {
if (index < 0) {
throw new IllegalArgumentException("index less than zero.");
}
int nitems = getItemCount();
Vector tempItems = new Vector();
/* Remove the item at index, nitems-index times
storing them in a temporary vector in the
order they appear on the menu.
*/
for (int i = index; i < nitems; i++) {
tempItems.addElement(getItem(index));
remove(index);
}
addSeparator();
/* Add the removed items back to the menu, they are
already in the correct order in the temp vector.
*/
for (int i = 0; i < tempItems.size(); i++) {
add((MenuItem) tempItems.elementAt(i));
}
}
}
/**
* Removes the menu item at the specified index from this menu.
* @param index the position of the item to be removed.
*/
public void remove(int index) {
synchronized (getTreeLock()) {
MenuItem mi = getItem(index);
items.removeElementAt(index);
MenuPeer peer = (MenuPeer) this.peer;
if (peer != null) {
mi.removeNotify();
mi.parent = null;
peer.delItem(index);
}
}
}
/**
* Removes the specified menu item from this menu.
* @param item the item to be removed from the menu.
* If <code>item</code> is <code>null</code>
* or is not in this menu, this method does
* nothing.
*/
public void remove(MenuComponent item) {
synchronized (getTreeLock()) {
int index = items.indexOf(item);
if (index >= 0) {
remove(index);
}
}
}
/**
* Removes all items from this menu.
* @since JDK1.0.
*/
public void removeAll() {
synchronized (getTreeLock()) {
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
remove(0);
}
}
}
/*
* Post an ActionEvent 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) {
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
MenuItem mi = getItem(i);
if (mi.handleShortcut(e)) {
return true;
}
}
return false;
}
MenuItem getShortcutMenuItem(MenuShortcut s) {
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
MenuItem mi = getItem(i).getShortcutMenuItem(s);
if (mi != null) {
return mi;
}
}
return null;
}
synchronized Enumeration shortcuts() {
Vector shortcuts = new Vector();
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
MenuItem mi = getItem(i);
if (mi instanceof Menu) {
Enumeration e = ((Menu) mi).shortcuts();
while (e.hasMoreElements()) {
shortcuts.addElement(e.nextElement());
}
} else {
MenuShortcut ms = mi.getShortcut();
if (ms != null) {
shortcuts.addElement(ms);
}
}
}
return shortcuts.elements();
}
void deleteShortcut(MenuShortcut s) {
int nitems = getItemCount();
for (int i = 0; i < nitems; i++) {
getItem(i).deleteShortcut(s);
}
}
/* Serialization support. A MenuContainer is responsible for
* restoring the parent fields of its children.
*/
private int menuSerializedDataVersion = 1;
private void writeObject(java.io.ObjectOutputStream s)
throws java.lang.ClassNotFoundException,
java.io.IOException {
s.defaultWriteObject();
}
private void readObject(java.io.ObjectInputStream s) throws java.lang.ClassNotFoundException, java.io.IOException {
checkPopup();
s.defaultReadObject();
for (int i = 0; i < items.size(); i++) {
MenuItem item = (MenuItem) items.elementAt(i);
checkNonCascading(item);
item.parent = this;
}
}
/**
* Gets the parameter string representing the state of this menu.
* This string is useful for debugging.
* @since JDK1.0nu.
*/
public String paramString() {
String str = ",tearOff=" + tearOff + ",isHelpMenu=" + isHelpMenu;
return super.paramString() + str;
}
}