J. Duke | 319a3b9 | 2007-12-01 00:00:00 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * Copyright 1995-2006 Sun Microsystems, Inc. All Rights Reserved. |
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 4 | * |
| 5 | * This code is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License version 2 only, as |
| 7 | * published by the Free Software Foundation. Sun designates this |
| 8 | * particular file as subject to the "Classpath" exception as provided |
| 9 | * by Sun in the LICENSE file that accompanied this code. |
| 10 | * |
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT |
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| 14 | * version 2 for more details (a copy is included in the LICENSE file that |
| 15 | * accompanied this code). |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License version |
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, |
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| 20 | * |
| 21 | * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
| 22 | * CA 95054 USA or visit www.sun.com if you need additional information or |
| 23 | * have any questions. |
| 24 | */ |
| 25 | package java.awt; |
| 26 | |
| 27 | import java.awt.peer.MenuItemPeer; |
| 28 | import java.awt.event.*; |
| 29 | import java.util.EventListener; |
| 30 | import java.io.ObjectOutputStream; |
| 31 | import java.io.ObjectInputStream; |
| 32 | import java.io.IOException; |
| 33 | import javax.accessibility.*; |
| 34 | |
| 35 | |
| 36 | /** |
| 37 | * All items in a menu must belong to the class |
| 38 | * <code>MenuItem</code>, or one of its subclasses. |
| 39 | * <p> |
| 40 | * The default <code>MenuItem</code> object embodies |
| 41 | * a simple labeled menu item. |
| 42 | * <p> |
| 43 | * This picture of a menu bar shows five menu items: |
| 44 | * <IMG SRC="doc-files/MenuBar-1.gif" alt="The following text describes this graphic." |
| 45 | * ALIGN=CENTER HSPACE=10 VSPACE=7> |
| 46 | * <br CLEAR=LEFT> |
| 47 | * The first two items are simple menu items, labeled |
| 48 | * <code>"Basic"</code> and <code>"Simple"</code>. |
| 49 | * Following these two items is a separator, which is itself |
| 50 | * a menu item, created with the label <code>"-"</code>. |
| 51 | * Next is an instance of <code>CheckboxMenuItem</code> |
| 52 | * labeled <code>"Check"</code>. The final menu item is a |
| 53 | * submenu labeled <code>"More Examples"</code>, |
| 54 | * and this submenu is an instance of <code>Menu</code>. |
| 55 | * <p> |
| 56 | * When a menu item is selected, AWT sends an action event to |
| 57 | * the menu item. Since the event is an |
| 58 | * instance of <code>ActionEvent</code>, the <code>processEvent</code> |
| 59 | * method examines the event and passes it along to |
| 60 | * <code>processActionEvent</code>. The latter method redirects the |
| 61 | * event to any <code>ActionListener</code> objects that have |
| 62 | * registered an interest in action events generated by this |
| 63 | * menu item. |
| 64 | * <P> |
| 65 | * Note that the subclass <code>Menu</code> overrides this behavior and |
| 66 | * does not send any event to the frame until one of its subitems is |
| 67 | * selected. |
| 68 | * |
| 69 | * @author Sami Shaio |
| 70 | */ |
| 71 | public class MenuItem extends MenuComponent implements Accessible { |
| 72 | |
| 73 | static { |
| 74 | /* ensure that the necessary native libraries are loaded */ |
| 75 | Toolkit.loadLibraries(); |
| 76 | if (!GraphicsEnvironment.isHeadless()) { |
| 77 | initIDs(); |
| 78 | } |
| 79 | } |
| 80 | |
| 81 | /** |
| 82 | * A value to indicate whether a menu item is enabled |
| 83 | * or not. If it is enabled, <code>enabled</code> will |
| 84 | * be set to true. Else <code>enabled</code> will |
| 85 | * be set to false. |
| 86 | * |
| 87 | * @serial |
| 88 | * @see #isEnabled() |
| 89 | * @see #setEnabled(boolean) |
| 90 | */ |
| 91 | boolean enabled = true; |
| 92 | |
| 93 | /** |
| 94 | * <code>label</code> is the label of a menu item. |
| 95 | * It can be any string. |
| 96 | * |
| 97 | * @serial |
| 98 | * @see #getLabel() |
| 99 | * @see #setLabel(String) |
| 100 | */ |
| 101 | String label; |
| 102 | |
| 103 | /** |
| 104 | * This field indicates the command tha has been issued |
| 105 | * by a particular menu item. |
| 106 | * By default the <code>actionCommand</code> |
| 107 | * is the label of the menu item, unless it has been |
| 108 | * set using setActionCommand. |
| 109 | * |
| 110 | * @serial |
| 111 | * @see #setActionCommand(String) |
| 112 | * @see #getActionCommand() |
| 113 | */ |
| 114 | String actionCommand; |
| 115 | |
| 116 | /** |
| 117 | * The eventMask is ONLY set by subclasses via enableEvents. |
| 118 | * The mask should NOT be set when listeners are registered |
| 119 | * so that we can distinguish the difference between when |
| 120 | * listeners request events and subclasses request them. |
| 121 | * |
| 122 | * @serial |
| 123 | */ |
| 124 | long eventMask; |
| 125 | |
| 126 | transient ActionListener actionListener; |
| 127 | |
| 128 | /** |
| 129 | * A sequence of key stokes that ia associated with |
| 130 | * a menu item. |
| 131 | * Note :in 1.1.2 you must use setActionCommand() |
| 132 | * on a menu item in order for its shortcut to |
| 133 | * work. |
| 134 | * |
| 135 | * @serial |
| 136 | * @see #getShortcut() |
| 137 | * @see #setShortcut(MenuShortcut) |
| 138 | * @see #deleteShortcut() |
| 139 | */ |
| 140 | private MenuShortcut shortcut = null; |
| 141 | |
| 142 | private static final String base = "menuitem"; |
| 143 | private static int nameCounter = 0; |
| 144 | |
| 145 | /* |
| 146 | * JDK 1.1 serialVersionUID |
| 147 | */ |
| 148 | private static final long serialVersionUID = -21757335363267194L; |
| 149 | |
| 150 | /** |
| 151 | * Constructs a new MenuItem with an empty label and no keyboard |
| 152 | * shortcut. |
| 153 | * @exception HeadlessException if GraphicsEnvironment.isHeadless() |
| 154 | * returns true. |
| 155 | * @see java.awt.GraphicsEnvironment#isHeadless |
| 156 | * @since JDK1.1 |
| 157 | */ |
| 158 | public MenuItem() throws HeadlessException { |
| 159 | this("", null); |
| 160 | } |
| 161 | |
| 162 | /** |
| 163 | * Constructs a new MenuItem with the specified label |
| 164 | * and no keyboard shortcut. Note that use of "-" in |
| 165 | * a label is reserved to indicate a separator between |
| 166 | * menu items. By default, all menu items except for |
| 167 | * separators are enabled. |
| 168 | * @param label the label for this menu item. |
| 169 | * @exception HeadlessException if GraphicsEnvironment.isHeadless() |
| 170 | * returns true. |
| 171 | * @see java.awt.GraphicsEnvironment#isHeadless |
| 172 | * @since JDK1.0 |
| 173 | */ |
| 174 | public MenuItem(String label) throws HeadlessException { |
| 175 | this(label, null); |
| 176 | } |
| 177 | |
| 178 | /** |
| 179 | * Create a menu item with an associated keyboard shortcut. |
| 180 | * Note that use of "-" in a label is reserved to indicate |
| 181 | * a separator between menu items. By default, all menu |
| 182 | * items except for separators are enabled. |
| 183 | * @param label the label for this menu item. |
| 184 | * @param s the instance of <code>MenuShortcut</code> |
| 185 | * associated with this menu item. |
| 186 | * @exception HeadlessException if GraphicsEnvironment.isHeadless() |
| 187 | * returns true. |
| 188 | * @see java.awt.GraphicsEnvironment#isHeadless |
| 189 | * @since JDK1.1 |
| 190 | */ |
| 191 | public MenuItem(String label, MenuShortcut s) throws HeadlessException { |
| 192 | this.label = label; |
| 193 | this.shortcut = s; |
| 194 | } |
| 195 | |
| 196 | /** |
| 197 | * Construct a name for this MenuComponent. Called by getName() when |
| 198 | * the name is null. |
| 199 | */ |
| 200 | String constructComponentName() { |
| 201 | synchronized (MenuItem.class) { |
| 202 | return base + nameCounter++; |
| 203 | } |
| 204 | } |
| 205 | |
| 206 | /** |
| 207 | * Creates the menu item's peer. The peer allows us to modify the |
| 208 | * appearance of the menu item without changing its functionality. |
| 209 | */ |
| 210 | public void addNotify() { |
| 211 | synchronized (getTreeLock()) { |
| 212 | if (peer == null) |
| 213 | peer = Toolkit.getDefaultToolkit().createMenuItem(this); |
| 214 | } |
| 215 | } |
| 216 | |
| 217 | /** |
| 218 | * Gets the label for this menu item. |
| 219 | * @return the label of this menu item, or <code>null</code> |
| 220 | if this menu item has no label. |
| 221 | * @see java.awt.MenuItem#setLabel |
| 222 | * @since JDK1.0 |
| 223 | */ |
| 224 | public String getLabel() { |
| 225 | return label; |
| 226 | } |
| 227 | |
| 228 | /** |
| 229 | * Sets the label for this menu item to the specified label. |
| 230 | * @param label the new label, or <code>null</code> for no label. |
| 231 | * @see java.awt.MenuItem#getLabel |
| 232 | * @since JDK1.0 |
| 233 | */ |
| 234 | public synchronized void setLabel(String label) { |
| 235 | this.label = label; |
| 236 | MenuItemPeer peer = (MenuItemPeer)this.peer; |
| 237 | if (peer != null) { |
| 238 | peer.setLabel(label); |
| 239 | } |
| 240 | } |
| 241 | |
| 242 | /** |
| 243 | * Checks whether this menu item is enabled. |
| 244 | * @see java.awt.MenuItem#setEnabled |
| 245 | * @since JDK1.0 |
| 246 | */ |
| 247 | public boolean isEnabled() { |
| 248 | return enabled; |
| 249 | } |
| 250 | |
| 251 | /** |
| 252 | * Sets whether or not this menu item can be chosen. |
| 253 | * @param b if <code>true</code>, enables this menu item; |
| 254 | * if <code>false</code>, disables it. |
| 255 | * @see java.awt.MenuItem#isEnabled |
| 256 | * @since JDK1.1 |
| 257 | */ |
| 258 | public synchronized void setEnabled(boolean b) { |
| 259 | enable(b); |
| 260 | } |
| 261 | |
| 262 | /** |
| 263 | * @deprecated As of JDK version 1.1, |
| 264 | * replaced by <code>setEnabled(boolean)</code>. |
| 265 | */ |
| 266 | @Deprecated |
| 267 | public synchronized void enable() { |
| 268 | enabled = true; |
| 269 | MenuItemPeer peer = (MenuItemPeer)this.peer; |
| 270 | if (peer != null) { |
| 271 | peer.enable(); |
| 272 | } |
| 273 | } |
| 274 | |
| 275 | /** |
| 276 | * @deprecated As of JDK version 1.1, |
| 277 | * replaced by <code>setEnabled(boolean)</code>. |
| 278 | */ |
| 279 | @Deprecated |
| 280 | public void enable(boolean b) { |
| 281 | if (b) { |
| 282 | enable(); |
| 283 | } else { |
| 284 | disable(); |
| 285 | } |
| 286 | } |
| 287 | |
| 288 | /** |
| 289 | * @deprecated As of JDK version 1.1, |
| 290 | * replaced by <code>setEnabled(boolean)</code>. |
| 291 | */ |
| 292 | @Deprecated |
| 293 | public synchronized void disable() { |
| 294 | enabled = false; |
| 295 | MenuItemPeer peer = (MenuItemPeer)this.peer; |
| 296 | if (peer != null) { |
| 297 | peer.disable(); |
| 298 | } |
| 299 | } |
| 300 | |
| 301 | /** |
| 302 | * Get the <code>MenuShortcut</code> object associated with this |
| 303 | * menu item, |
| 304 | * @return the menu shortcut associated with this menu item, |
| 305 | * or <code>null</code> if none has been specified. |
| 306 | * @see java.awt.MenuItem#setShortcut |
| 307 | * @since JDK1.1 |
| 308 | */ |
| 309 | public MenuShortcut getShortcut() { |
| 310 | return shortcut; |
| 311 | } |
| 312 | |
| 313 | /** |
| 314 | * Set the <code>MenuShortcut</code> object associated with this |
| 315 | * menu item. If a menu shortcut is already associated with |
| 316 | * this menu item, it is replaced. |
| 317 | * @param s the menu shortcut to associate |
| 318 | * with this menu item. |
| 319 | * @see java.awt.MenuItem#getShortcut |
| 320 | * @since JDK1.1 |
| 321 | */ |
| 322 | public void setShortcut(MenuShortcut s) { |
| 323 | shortcut = s; |
| 324 | MenuItemPeer peer = (MenuItemPeer)this.peer; |
| 325 | if (peer != null) { |
| 326 | peer.setLabel(label); |
| 327 | } |
| 328 | } |
| 329 | |
| 330 | /** |
| 331 | * Delete any <code>MenuShortcut</code> object associated |
| 332 | * with this menu item. |
| 333 | * @since JDK1.1 |
| 334 | */ |
| 335 | public void deleteShortcut() { |
| 336 | shortcut = null; |
| 337 | MenuItemPeer peer = (MenuItemPeer)this.peer; |
| 338 | if (peer != null) { |
| 339 | peer.setLabel(label); |
| 340 | } |
| 341 | } |
| 342 | |
| 343 | /* |
| 344 | * Delete a matching MenuShortcut associated with this MenuItem. |
| 345 | * Used when iterating Menus. |
| 346 | */ |
| 347 | void deleteShortcut(MenuShortcut s) { |
| 348 | if (s.equals(shortcut)) { |
| 349 | shortcut = null; |
| 350 | MenuItemPeer peer = (MenuItemPeer)this.peer; |
| 351 | if (peer != null) { |
| 352 | peer.setLabel(label); |
| 353 | } |
| 354 | } |
| 355 | } |
| 356 | |
| 357 | /* |
| 358 | * The main goal of this method is to post an appropriate event |
| 359 | * to the event queue when menu shortcut is pressed. However, |
| 360 | * in subclasses this method may do more than just posting |
| 361 | * an event. |
| 362 | */ |
| 363 | void doMenuEvent(long when, int modifiers) { |
| 364 | Toolkit.getEventQueue().postEvent( |
| 365 | new ActionEvent(this, ActionEvent.ACTION_PERFORMED, |
| 366 | getActionCommand(), when, modifiers)); |
| 367 | } |
| 368 | |
| 369 | /* |
| 370 | * Returns true if the item and all its ancestors are |
| 371 | * enabled, false otherwise |
| 372 | */ |
| 373 | private final boolean isItemEnabled() { |
| 374 | // Fix For 6185151: Menu shortcuts of all menuitems within a menu |
| 375 | // should be disabled when the menu itself is disabled |
| 376 | if (!isEnabled()) { |
| 377 | return false; |
| 378 | } |
| 379 | MenuContainer container = getParent_NoClientCode(); |
| 380 | do { |
| 381 | if (!(container instanceof Menu)) { |
| 382 | return true; |
| 383 | } |
| 384 | Menu menu = (Menu)container; |
| 385 | if (!menu.isEnabled()) { |
| 386 | return false; |
| 387 | } |
| 388 | container = menu.getParent_NoClientCode(); |
| 389 | } while (container != null); |
| 390 | return true; |
| 391 | } |
| 392 | |
| 393 | /* |
| 394 | * Post an ActionEvent to the target (on |
| 395 | * keydown) and the item is enabled. |
| 396 | * Returns true if there is an associated shortcut. |
| 397 | */ |
| 398 | boolean handleShortcut(KeyEvent e) { |
| 399 | MenuShortcut s = new MenuShortcut(e.getKeyCode(), |
| 400 | (e.getModifiers() & InputEvent.SHIFT_MASK) > 0); |
| 401 | // Fix For 6185151: Menu shortcuts of all menuitems within a menu |
| 402 | // should be disabled when the menu itself is disabled |
| 403 | if (s.equals(shortcut) && isItemEnabled()) { |
| 404 | // MenuShortcut match -- issue an event on keydown. |
| 405 | if (e.getID() == KeyEvent.KEY_PRESSED) { |
| 406 | doMenuEvent(e.getWhen(), e.getModifiers()); |
| 407 | } else { |
| 408 | // silently eat key release. |
| 409 | } |
| 410 | return true; |
| 411 | } |
| 412 | return false; |
| 413 | } |
| 414 | |
| 415 | MenuItem getShortcutMenuItem(MenuShortcut s) { |
| 416 | return (s.equals(shortcut)) ? this : null; |
| 417 | } |
| 418 | |
| 419 | /** |
| 420 | * Enables event delivery to this menu item for events |
| 421 | * to be defined by the specified event mask parameter |
| 422 | * <p> |
| 423 | * Since event types are automatically enabled when a listener for |
| 424 | * that type is added to the menu item, this method only needs |
| 425 | * to be invoked by subclasses of <code>MenuItem</code> which desire to |
| 426 | * have the specified event types delivered to <code>processEvent</code> |
| 427 | * regardless of whether a listener is registered. |
| 428 | * |
| 429 | * @param eventsToEnable the event mask defining the event types |
| 430 | * @see java.awt.MenuItem#processEvent |
| 431 | * @see java.awt.MenuItem#disableEvents |
| 432 | * @see java.awt.Component#enableEvents |
| 433 | * @since JDK1.1 |
| 434 | */ |
| 435 | protected final void enableEvents(long eventsToEnable) { |
| 436 | eventMask |= eventsToEnable; |
| 437 | newEventsOnly = true; |
| 438 | } |
| 439 | |
| 440 | /** |
| 441 | * Disables event delivery to this menu item for events |
| 442 | * defined by the specified event mask parameter. |
| 443 | * |
| 444 | * @param eventsToDisable the event mask defining the event types |
| 445 | * @see java.awt.MenuItem#processEvent |
| 446 | * @see java.awt.MenuItem#enableEvents |
| 447 | * @see java.awt.Component#disableEvents |
| 448 | * @since JDK1.1 |
| 449 | */ |
| 450 | protected final void disableEvents(long eventsToDisable) { |
| 451 | eventMask &= ~eventsToDisable; |
| 452 | } |
| 453 | |
| 454 | /** |
| 455 | * Sets the command name of the action event that is fired |
| 456 | * by this menu item. |
| 457 | * <p> |
| 458 | * By default, the action command is set to the label of |
| 459 | * the menu item. |
| 460 | * @param command the action command to be set |
| 461 | * for this menu item. |
| 462 | * @see java.awt.MenuItem#getActionCommand |
| 463 | * @since JDK1.1 |
| 464 | */ |
| 465 | public void setActionCommand(String command) { |
| 466 | actionCommand = command; |
| 467 | } |
| 468 | |
| 469 | /** |
| 470 | * Gets the command name of the action event that is fired |
| 471 | * by this menu item. |
| 472 | * @see java.awt.MenuItem#setActionCommand |
| 473 | * @since JDK1.1 |
| 474 | */ |
| 475 | public String getActionCommand() { |
| 476 | return getActionCommandImpl(); |
| 477 | } |
| 478 | |
| 479 | // This is final so it can be called on the Toolkit thread. |
| 480 | final String getActionCommandImpl() { |
| 481 | return (actionCommand == null? label : actionCommand); |
| 482 | } |
| 483 | |
| 484 | /** |
| 485 | * Adds the specified action listener to receive action events |
| 486 | * from this menu item. |
| 487 | * If l is null, no exception is thrown and no action is performed. |
| 488 | * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads" |
| 489 | * >AWT Threading Issues</a> for details on AWT's threading model. |
| 490 | * |
| 491 | * @param l the action listener. |
| 492 | * @see #removeActionListener |
| 493 | * @see #getActionListeners |
| 494 | * @see java.awt.event.ActionEvent |
| 495 | * @see java.awt.event.ActionListener |
| 496 | * @since JDK1.1 |
| 497 | */ |
| 498 | public synchronized void addActionListener(ActionListener l) { |
| 499 | if (l == null) { |
| 500 | return; |
| 501 | } |
| 502 | actionListener = AWTEventMulticaster.add(actionListener, l); |
| 503 | newEventsOnly = true; |
| 504 | } |
| 505 | |
| 506 | /** |
| 507 | * Removes the specified action listener so it no longer receives |
| 508 | * action events from this menu item. |
| 509 | * If l is null, no exception is thrown and no action is performed. |
| 510 | * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads" |
| 511 | * >AWT Threading Issues</a> for details on AWT's threading model. |
| 512 | * |
| 513 | * @param l the action listener. |
| 514 | * @see #addActionListener |
| 515 | * @see #getActionListeners |
| 516 | * @see java.awt.event.ActionEvent |
| 517 | * @see java.awt.event.ActionListener |
| 518 | * @since JDK1.1 |
| 519 | */ |
| 520 | public synchronized void removeActionListener(ActionListener l) { |
| 521 | if (l == null) { |
| 522 | return; |
| 523 | } |
| 524 | actionListener = AWTEventMulticaster.remove(actionListener, l); |
| 525 | } |
| 526 | |
| 527 | /** |
| 528 | * Returns an array of all the action listeners |
| 529 | * registered on this menu item. |
| 530 | * |
| 531 | * @return all of this menu item's <code>ActionListener</code>s |
| 532 | * or an empty array if no action |
| 533 | * listeners are currently registered |
| 534 | * |
| 535 | * @see #addActionListener |
| 536 | * @see #removeActionListener |
| 537 | * @see java.awt.event.ActionEvent |
| 538 | * @see java.awt.event.ActionListener |
| 539 | * @since 1.4 |
| 540 | */ |
| 541 | public synchronized ActionListener[] getActionListeners() { |
| 542 | return (ActionListener[])(getListeners(ActionListener.class)); |
| 543 | } |
| 544 | |
| 545 | /** |
| 546 | * Returns an array of all the objects currently registered |
| 547 | * as <code><em>Foo</em>Listener</code>s |
| 548 | * upon this <code>MenuItem</code>. |
| 549 | * <code><em>Foo</em>Listener</code>s are registered using the |
| 550 | * <code>add<em>Foo</em>Listener</code> method. |
| 551 | * |
| 552 | * <p> |
| 553 | * You can specify the <code>listenerType</code> argument |
| 554 | * with a class literal, such as |
| 555 | * <code><em>Foo</em>Listener.class</code>. |
| 556 | * For example, you can query a |
| 557 | * <code>MenuItem</code> <code>m</code> |
| 558 | * for its action listeners with the following code: |
| 559 | * |
| 560 | * <pre>ActionListener[] als = (ActionListener[])(m.getListeners(ActionListener.class));</pre> |
| 561 | * |
| 562 | * If no such listeners exist, this method returns an empty array. |
| 563 | * |
| 564 | * @param listenerType the type of listeners requested; this parameter |
| 565 | * should specify an interface that descends from |
| 566 | * <code>java.util.EventListener</code> |
| 567 | * @return an array of all objects registered as |
| 568 | * <code><em>Foo</em>Listener</code>s on this menu item, |
| 569 | * or an empty array if no such |
| 570 | * listeners have been added |
| 571 | * @exception ClassCastException if <code>listenerType</code> |
| 572 | * doesn't specify a class or interface that implements |
| 573 | * <code>java.util.EventListener</code> |
| 574 | * |
| 575 | * @see #getActionListeners |
| 576 | * @since 1.3 |
| 577 | */ |
| 578 | public <T extends EventListener> T[] getListeners(Class<T> listenerType) { |
| 579 | EventListener l = null; |
| 580 | if (listenerType == ActionListener.class) { |
| 581 | l = actionListener; |
| 582 | } |
| 583 | return AWTEventMulticaster.getListeners(l, listenerType); |
| 584 | } |
| 585 | |
| 586 | /** |
| 587 | * Processes events on this menu item. If the event is an |
| 588 | * instance of <code>ActionEvent</code>, it invokes |
| 589 | * <code>processActionEvent</code>, another method |
| 590 | * defined by <code>MenuItem</code>. |
| 591 | * <p> |
| 592 | * Currently, menu items only support action events. |
| 593 | * <p>Note that if the event parameter is <code>null</code> |
| 594 | * the behavior is unspecified and may result in an |
| 595 | * exception. |
| 596 | * |
| 597 | * @param e the event |
| 598 | * @see java.awt.MenuItem#processActionEvent |
| 599 | * @since JDK1.1 |
| 600 | */ |
| 601 | protected void processEvent(AWTEvent e) { |
| 602 | if (e instanceof ActionEvent) { |
| 603 | processActionEvent((ActionEvent)e); |
| 604 | } |
| 605 | } |
| 606 | |
| 607 | // REMIND: remove when filtering is done at lower level |
| 608 | boolean eventEnabled(AWTEvent e) { |
| 609 | if (e.id == ActionEvent.ACTION_PERFORMED) { |
| 610 | if ((eventMask & AWTEvent.ACTION_EVENT_MASK) != 0 || |
| 611 | actionListener != null) { |
| 612 | return true; |
| 613 | } |
| 614 | return false; |
| 615 | } |
| 616 | return super.eventEnabled(e); |
| 617 | } |
| 618 | |
| 619 | /** |
| 620 | * Processes action events occurring on this menu item, |
| 621 | * by dispatching them to any registered |
| 622 | * <code>ActionListener</code> objects. |
| 623 | * This method is not called unless action events are |
| 624 | * enabled for this component. Action events are enabled |
| 625 | * when one of the following occurs: |
| 626 | * <p><ul> |
| 627 | * <li>An <code>ActionListener</code> object is registered |
| 628 | * via <code>addActionListener</code>. |
| 629 | * <li>Action events are enabled via <code>enableEvents</code>. |
| 630 | * </ul> |
| 631 | * <p>Note that if the event parameter is <code>null</code> |
| 632 | * the behavior is unspecified and may result in an |
| 633 | * exception. |
| 634 | * |
| 635 | * @param e the action event |
| 636 | * @see java.awt.event.ActionEvent |
| 637 | * @see java.awt.event.ActionListener |
| 638 | * @see java.awt.MenuItem#enableEvents |
| 639 | * @since JDK1.1 |
| 640 | */ |
| 641 | protected void processActionEvent(ActionEvent e) { |
| 642 | ActionListener listener = actionListener; |
| 643 | if (listener != null) { |
| 644 | listener.actionPerformed(e); |
| 645 | } |
| 646 | } |
| 647 | |
| 648 | /** |
| 649 | * Returns a string representing the state of this <code>MenuItem</code>. |
| 650 | * This method is intended to be used only for debugging purposes, and the |
| 651 | * content and format of the returned string may vary between |
| 652 | * implementations. The returned string may be empty but may not be |
| 653 | * <code>null</code>. |
| 654 | * |
| 655 | * @return the parameter string of this menu item |
| 656 | */ |
| 657 | public String paramString() { |
| 658 | String str = ",label=" + label; |
| 659 | if (shortcut != null) { |
| 660 | str += ",shortcut=" + shortcut; |
| 661 | } |
| 662 | return super.paramString() + str; |
| 663 | } |
| 664 | |
| 665 | |
| 666 | /* Serialization support. |
| 667 | */ |
| 668 | |
| 669 | /** |
| 670 | * Menu item serialized data version. |
| 671 | * |
| 672 | * @serial |
| 673 | */ |
| 674 | private int menuItemSerializedDataVersion = 1; |
| 675 | |
| 676 | /** |
| 677 | * Writes default serializable fields to stream. Writes |
| 678 | * a list of serializable <code>ActionListeners</code> |
| 679 | * as optional data. The non-serializable listeners are |
| 680 | * detected and no attempt is made to serialize them. |
| 681 | * |
| 682 | * @param s the <code>ObjectOutputStream</code> to write |
| 683 | * @serialData <code>null</code> terminated sequence of 0 |
| 684 | * or more pairs; the pair consists of a <code>String</code> |
| 685 | * and an <code>Object</code>; the <code>String</code> |
| 686 | * indicates the type of object and is one of the following: |
| 687 | * <code>actionListenerK</code> indicating an |
| 688 | * <code>ActionListener</code> object |
| 689 | * |
| 690 | * @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener) |
| 691 | * @see #readObject(ObjectInputStream) |
| 692 | */ |
| 693 | private void writeObject(ObjectOutputStream s) |
| 694 | throws IOException |
| 695 | { |
| 696 | s.defaultWriteObject(); |
| 697 | |
| 698 | AWTEventMulticaster.save(s, actionListenerK, actionListener); |
| 699 | s.writeObject(null); |
| 700 | } |
| 701 | |
| 702 | /** |
| 703 | * Reads the <code>ObjectInputStream</code> and if it |
| 704 | * isn't <code>null</code> adds a listener to receive |
| 705 | * action events fired by the <code>Menu</code> Item. |
| 706 | * Unrecognized keys or values will be ignored. |
| 707 | * |
| 708 | * @param s the <code>ObjectInputStream</code> to read |
| 709 | * @exception HeadlessException if |
| 710 | * <code>GraphicsEnvironment.isHeadless</code> returns |
| 711 | * <code>true</code> |
| 712 | * @see #removeActionListener(ActionListener) |
| 713 | * @see #addActionListener(ActionListener) |
| 714 | * @see #writeObject(ObjectOutputStream) |
| 715 | */ |
| 716 | private void readObject(ObjectInputStream s) |
| 717 | throws ClassNotFoundException, IOException, HeadlessException |
| 718 | { |
| 719 | // HeadlessException will be thrown from MenuComponent's readObject |
| 720 | s.defaultReadObject(); |
| 721 | |
| 722 | Object keyOrNull; |
| 723 | while(null != (keyOrNull = s.readObject())) { |
| 724 | String key = ((String)keyOrNull).intern(); |
| 725 | |
| 726 | if (actionListenerK == key) |
| 727 | addActionListener((ActionListener)(s.readObject())); |
| 728 | |
| 729 | else // skip value for unrecognized key |
| 730 | s.readObject(); |
| 731 | } |
| 732 | } |
| 733 | |
| 734 | /** |
| 735 | * Initialize JNI field and method IDs |
| 736 | */ |
| 737 | private static native void initIDs(); |
| 738 | |
| 739 | |
| 740 | ///////////////// |
| 741 | // Accessibility support |
| 742 | //////////////// |
| 743 | |
| 744 | /** |
| 745 | * Gets the AccessibleContext associated with this MenuItem. |
| 746 | * For menu items, the AccessibleContext takes the form of an |
| 747 | * AccessibleAWTMenuItem. |
| 748 | * A new AccessibleAWTMenuItem instance is created if necessary. |
| 749 | * |
| 750 | * @return an AccessibleAWTMenuItem that serves as the |
| 751 | * AccessibleContext of this MenuItem |
| 752 | * @since 1.3 |
| 753 | */ |
| 754 | public AccessibleContext getAccessibleContext() { |
| 755 | if (accessibleContext == null) { |
| 756 | accessibleContext = new AccessibleAWTMenuItem(); |
| 757 | } |
| 758 | return accessibleContext; |
| 759 | } |
| 760 | |
| 761 | /** |
| 762 | * Inner class of MenuItem used to provide default support for |
| 763 | * accessibility. This class is not meant to be used directly by |
| 764 | * application developers, but is instead meant only to be |
| 765 | * subclassed by menu component developers. |
| 766 | * <p> |
| 767 | * This class implements accessibility support for the |
| 768 | * <code>MenuItem</code> class. It provides an implementation of the |
| 769 | * Java Accessibility API appropriate to menu item user-interface elements. |
| 770 | * @since 1.3 |
| 771 | */ |
| 772 | protected class AccessibleAWTMenuItem extends AccessibleAWTMenuComponent |
| 773 | implements AccessibleAction, AccessibleValue |
| 774 | { |
| 775 | /* |
| 776 | * JDK 1.3 serialVersionUID |
| 777 | */ |
| 778 | private static final long serialVersionUID = -217847831945965825L; |
| 779 | |
| 780 | /** |
| 781 | * Get the accessible name of this object. |
| 782 | * |
| 783 | * @return the localized name of the object -- can be null if this |
| 784 | * object does not have a name |
| 785 | */ |
| 786 | public String getAccessibleName() { |
| 787 | if (accessibleName != null) { |
| 788 | return accessibleName; |
| 789 | } else { |
| 790 | if (getLabel() == null) { |
| 791 | return super.getAccessibleName(); |
| 792 | } else { |
| 793 | return getLabel(); |
| 794 | } |
| 795 | } |
| 796 | } |
| 797 | |
| 798 | /** |
| 799 | * Get the role of this object. |
| 800 | * |
| 801 | * @return an instance of AccessibleRole describing the role of the |
| 802 | * object |
| 803 | */ |
| 804 | public AccessibleRole getAccessibleRole() { |
| 805 | return AccessibleRole.MENU_ITEM; |
| 806 | } |
| 807 | |
| 808 | /** |
| 809 | * Get the AccessibleAction associated with this object. In the |
| 810 | * implementation of the Java Accessibility API for this class, |
| 811 | * return this object, which is responsible for implementing the |
| 812 | * AccessibleAction interface on behalf of itself. |
| 813 | * |
| 814 | * @return this object |
| 815 | */ |
| 816 | public AccessibleAction getAccessibleAction() { |
| 817 | return this; |
| 818 | } |
| 819 | |
| 820 | /** |
| 821 | * Get the AccessibleValue associated with this object. In the |
| 822 | * implementation of the Java Accessibility API for this class, |
| 823 | * return this object, which is responsible for implementing the |
| 824 | * AccessibleValue interface on behalf of itself. |
| 825 | * |
| 826 | * @return this object |
| 827 | */ |
| 828 | public AccessibleValue getAccessibleValue() { |
| 829 | return this; |
| 830 | } |
| 831 | |
| 832 | /** |
| 833 | * Returns the number of Actions available in this object. The |
| 834 | * default behavior of a menu item is to have one action. |
| 835 | * |
| 836 | * @return 1, the number of Actions in this object |
| 837 | */ |
| 838 | public int getAccessibleActionCount() { |
| 839 | return 1; |
| 840 | } |
| 841 | |
| 842 | /** |
| 843 | * Return a description of the specified action of the object. |
| 844 | * |
| 845 | * @param i zero-based index of the actions |
| 846 | */ |
| 847 | public String getAccessibleActionDescription(int i) { |
| 848 | if (i == 0) { |
| 849 | // [[[PENDING: WDW -- need to provide a localized string]]] |
| 850 | return new String("click"); |
| 851 | } else { |
| 852 | return null; |
| 853 | } |
| 854 | } |
| 855 | |
| 856 | /** |
| 857 | * Perform the specified Action on the object |
| 858 | * |
| 859 | * @param i zero-based index of actions |
| 860 | * @return true if the action was performed; otherwise false. |
| 861 | */ |
| 862 | public boolean doAccessibleAction(int i) { |
| 863 | if (i == 0) { |
| 864 | // Simulate a button click |
| 865 | Toolkit.getEventQueue().postEvent( |
| 866 | new ActionEvent(MenuItem.this, |
| 867 | ActionEvent.ACTION_PERFORMED, |
| 868 | MenuItem.this.getActionCommand(), |
| 869 | EventQueue.getMostRecentEventTime(), |
| 870 | 0)); |
| 871 | return true; |
| 872 | } else { |
| 873 | return false; |
| 874 | } |
| 875 | } |
| 876 | |
| 877 | /** |
| 878 | * Get the value of this object as a Number. |
| 879 | * |
| 880 | * @return An Integer of 0 if this isn't selected or an Integer of 1 if |
| 881 | * this is selected. |
| 882 | * @see javax.swing.AbstractButton#isSelected() |
| 883 | */ |
| 884 | public Number getCurrentAccessibleValue() { |
| 885 | return Integer.valueOf(0); |
| 886 | } |
| 887 | |
| 888 | /** |
| 889 | * Set the value of this object as a Number. |
| 890 | * |
| 891 | * @return True if the value was set. |
| 892 | */ |
| 893 | public boolean setCurrentAccessibleValue(Number n) { |
| 894 | return false; |
| 895 | } |
| 896 | |
| 897 | /** |
| 898 | * Get the minimum value of this object as a Number. |
| 899 | * |
| 900 | * @return An Integer of 0. |
| 901 | */ |
| 902 | public Number getMinimumAccessibleValue() { |
| 903 | return Integer.valueOf(0); |
| 904 | } |
| 905 | |
| 906 | /** |
| 907 | * Get the maximum value of this object as a Number. |
| 908 | * |
| 909 | * @return An Integer of 0. |
| 910 | */ |
| 911 | public Number getMaximumAccessibleValue() { |
| 912 | return Integer.valueOf(0); |
| 913 | } |
| 914 | |
| 915 | } // class AccessibleAWTMenuItem |
| 916 | |
| 917 | } |