libjava/java/awt/MenuBar.java

   1 /* MenuBar.java -- An AWT menu bar class
   2    Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package java.awt;
  40
  41 import java.awt.peer.MenuBarPeer;
  42 import java.awt.peer.MenuComponentPeer;
  43
  44 import java.io.Serializable;
  45 import java.util.Enumeration;
  46 import java.util.Vector;
  47
  48 /**
  49   * This class implements a menu bar in the AWT system.
  50   *
  51   * @author Aaron M. Renn (arenn@urbanophile.com)
  52   * @author Tom Tromey <tromey@redhat.com>
  53   */
  54 public class MenuBar extends MenuComponent
  55   implements MenuContainer, Serializable
  56 {
  57
  58 /*
  59  * Static Variables
  60  */
  61
  62 // Serialization Constant
  63 private static final long serialVersionUID = -4930327919388951260L;
  64
  65 /*************************************************************************/
  66
  67 /*
  68  * Instance Variables
  69  */
  70
  71 /**
  72   * @serial The menu used for providing help information
  73   */
  74 private Menu helpMenu;
  75
  76 /**
  77   * @serial The menus contained in this menu bar.
  78   */
  79 private Vector menus = new Vector();
  80
  81 /*************************************************************************/
  82
  83 /*
  84  * Constructors
  85  */
  86
  87 /**
  88   * Initializes a new instance of <code>MenuBar</code>.
  89   *
  90   * @exception HeadlessException If GraphicsEnvironment.isHeadless() is true.
  91   */
  92 public
  93 MenuBar()
  94 {
  95   if (GraphicsEnvironment.isHeadless())
  96     throw new HeadlessException ();
  97 }
  98
  99 /*************************************************************************/
 100
 101 /*
 102  * Instance Methods
 103  */
 104
 105 /**
 106   * Returns the help menu for this menu bar.  This may be <code>null</code>.
 107   *
 108   * @return The help menu for this menu bar.
 109   */
 110 public Menu
 111 getHelpMenu()
 112 {
 113   return(helpMenu);
 114 }
 115
 116 /*************************************************************************/
 117
 118 /**
 119   * Sets the help menu for this menu bar.
 120   *
 121   * @param helpMenu The new help menu for this menu bar.
 122   */
 123 public synchronized void
 124 setHelpMenu(Menu menu)
 125 {
 126   if (helpMenu != null)
 127     {
 128       helpMenu.removeNotify ();
 129       helpMenu.parent = null;
 130     }
 131
 132   if (menu.parent != null)
 133     menu.parent.remove (menu);
 134   if (menu.parent != null)
 135     menu.parent.remove (menu);
 136   menu.parent = this;
 137
 138   if (peer != null)
 139     {
 140       MenuBarPeer mp = (MenuBarPeer) peer;
 141       mp.addHelpMenu (menu);
 142     }
 143 }
 144
 145 /*************************************************************************/
 146
 147 /** Add a menu to this MenuBar.  If the menu has already has a
 148  * parent, it is first removed from its old parent before being
 149  * added.
 150  *
 151  * @param menu The menu to add.
 152  *
 153  * @return The menu that was added.
 154  */
 155 public synchronized Menu
 156 add(Menu menu)
 157 {
 158   if (menu.parent != null)
 159     menu.parent.remove (menu);
 160
 161   menu.parent = this;
 162   menus.addElement(menu);
 163
 164   if (peer != null)
 165     {
 166       MenuBarPeer mp = (MenuBarPeer) peer;
 167       mp.addMenu (menu);
 168     }
 169
 170   return(menu);
 171 }
 172
 173 /*************************************************************************/
 174
 175 /**
 176   * Removes the menu at the specified index.
 177   *
 178   * @param index The index of the menu to remove from the menu bar.
 179   */
 180 public synchronized void
 181 remove(int index)
 182 {
 183   Menu m = (Menu) menus.get (index);
 184   menus.remove (index);
 185   m.removeNotify ();
 186   m.parent = null;
 187
 188   if (peer != null)
 189     {
 190       MenuBarPeer mp = (MenuBarPeer) peer;
 191       mp.delMenu (index);
 192     }
 193 }
 194
 195 /*************************************************************************/
 196
 197 /**
 198   * Removes the specified menu from the menu bar.
 199   *
 200   * @param menu The menu to remove from the menu bar.
 201   */
 202 public void
 203 remove(MenuComponent menu)
 204 {
 205   int index = menus.indexOf(menu);
 206   if (index == -1)
 207     return;
 208
 209   remove(index);
 210 }
 211
 212 /*************************************************************************/
 213
 214 /**
 215   * Returns the number of elements in this menu bar.
 216   *
 217   * @return The number of elements in the menu bar.
 218   */
 219 public int
 220 getMenuCount()
 221 {
 222   // FIXME: How does the help menu fit in here?
 223   return(menus.size());
 224 }
 225
 226 /*************************************************************************/
 227
 228 /**
 229   * Returns the number of elements in this menu bar.
 230   *
 231   * @return The number of elements in the menu bar.
 232   *
 233   * @deprecated This method is deprecated in favor of <code>getMenuCount()</code>.
 234   */
 235 public int
 236 countMenus()
 237 {
 238   return(getMenuCount());
 239 }
 240
 241 /*************************************************************************/
 242
 243 /**
 244   * Returns the menu at the specified index.
 245   *
 246   * @return The requested menu.
 247   *
 248   * @exception ArrayIndexOutOfBoundsException If the index is not valid.
 249   */
 250 public Menu
 251 getMenu(int index)
 252 {
 253   return((Menu)menus.elementAt(index));
 254 }
 255
 256 /*************************************************************************/
 257
 258 /**
 259   * Creates this object's native peer.
 260   */
 261 public void
 262 addNotify()
 263 {
 264   if (getPeer() == null)
 265     setPeer((MenuComponentPeer)getToolkit().createMenuBar(this));
 266 }
 267
 268 /*************************************************************************/
 269
 270 /**
 271   * Destroys this object's native peer.
 272   */
 273 public void
 274 removeNotify()
 275 {
 276   super.removeNotify();
 277 }
 278
 279 /*************************************************************************/
 280
 281 /**
 282   * Returns a list of all shortcuts for the menus in this menu bar.
 283   *
 284   * @return A list of all shortcuts for the menus in this menu bar.
 285   */
 286 public synchronized Enumeration
 287 shortcuts()
 288 {
 289   Vector shortcuts = new Vector();
 290   Enumeration e = menus.elements();
 291
 292   while (e.hasMoreElements())
 293     {
 294       Menu menu = (Menu)e.nextElement();
 295       if (menu.getShortcut() != null)
 296         shortcuts.addElement(menu.getShortcut());
 297     }
 298
 299   return(shortcuts.elements());
 300 }
 301
 302 /*************************************************************************/
 303
 304 /**
 305   * Returns the menu item for the specified shortcut, or <code>null</code>
 306   * if no such item exists.
 307   *
 308   * @param shortcut The shortcut to return the menu item for.
 309   *
 310   * @return The menu item for the specified shortcut.
 311   */
 312 public MenuItem
 313 getShortcutMenuItem(MenuShortcut shortcut)
 314 {
 315   Enumeration e = menus.elements();
 316
 317   while (e.hasMoreElements())
 318     {
 319       Menu menu = (Menu)e.nextElement();
 320       MenuShortcut s = menu.getShortcut();
 321       if ((s != null) && (s.equals(shortcut)))
 322         return(menu);
 323     }
 324
 325   return(null);
 326 }
 327
 328 /*************************************************************************/
 329
 330 /**
 331   * Deletes the specified menu shortcut.
 332   *
 333   * @param shortcut The shortcut to delete.
 334   */
 335 public void
 336 deleteShortcut(MenuShortcut shortcut)
 337 {
 338   MenuItem it;
 339   // This is a slow implementation, but it probably doesn't matter.
 340   while ((it = getShortcutMenuItem (shortcut)) != null)
 341     it.deleteShortcut ();
 342 }
 343
 344 } // class MenuBar