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| 1 | /* | ||
| 2 | * Copyright (c) 1995, 2006, Oracle and/or its affiliates. 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. Oracle designates this | ||
| 8 | * particular file as subject to the "Classpath" exception as provided | ||
| 9 | * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | ||
| 22 | * or visit www.oracle.com if you need additional information or have any | ||
| 23 | * questions. | ||
| 24 | */ | ||
| 25 | package java.awt; | ||
| 26 | |||
| 27 | import java.awt.peer.CheckboxMenuItemPeer; | ||
| 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 | * This class represents a check box that can be included in a menu. | ||
| 38 | * Selecting the check box in the menu changes its state from | ||
| 39 | * "on" to "off" or from "off" to "on." | ||
| 40 | * <p> | ||
| 41 | * The following picture depicts a menu which contains an instance | ||
| 42 | * of <code>CheckBoxMenuItem</code>: | ||
| 43 | * <p> | ||
| 44 | * <img src="doc-files/MenuBar-1.gif" | ||
| 45 | * alt="Menu labeled Examples, containing items Basic, Simple, Check, and More Examples. The Check item is a CheckBoxMenuItem instance, in the off state." | ||
| 46 | * ALIGN=center HSPACE=10 VSPACE=7> | ||
| 47 | * <p> | ||
| 48 | * The item labeled <code>Check</code> shows a check box menu item | ||
| 49 | * in its "off" state. | ||
| 50 | * <p> | ||
| 51 | * When a check box menu item is selected, AWT sends an item event to | ||
| 52 | * the item. Since the event is an instance of <code>ItemEvent</code>, | ||
| 53 | * the <code>processEvent</code> method examines the event and passes | ||
| 54 | * it along to <code>processItemEvent</code>. The latter method redirects | ||
| 55 | * the event to any <code>ItemListener</code> objects that have | ||
| 56 | * registered an interest in item events generated by this menu item. | ||
| 57 | * | ||
| 58 | * @author Sami Shaio | ||
| 59 | * @see java.awt.event.ItemEvent | ||
| 60 | * @see java.awt.event.ItemListener | ||
| 61 | * @since JDK1.0 | ||
| 62 | */ | ||
| 63 | public class CheckboxMenuItem extends MenuItem implements ItemSelectable, Accessible { | ||
| 64 | |||
| 65 | static { | ||
| 66 | /* ensure that the necessary native libraries are loaded */ | ||
| 67 | Toolkit.loadLibraries(); | ||
| 68 | if (!GraphicsEnvironment.isHeadless()) { | ||
| 69 | initIDs(); | ||
| 70 | } | ||
| 71 | } | ||
| 72 | |||
| 73 | /** | ||
| 74 | * The state of a checkbox menu item | ||
| 75 | * @serial | ||
| 76 | * @see #getState() | ||
| 77 | * @see #setState(boolean) | ||
| 78 | */ | ||
| 79 | boolean state = false; | ||
| 80 | |||
| 81 | transient ItemListener itemListener; | ||
| 82 | |||
| 83 | private static final String base = "chkmenuitem"; | ||
| 84 | private static int nameCounter = 0; | ||
| 85 | |||
| 86 | /* | ||
| 87 | * JDK 1.1 serialVersionUID | ||
| 88 | */ | ||
| 89 | private static final long serialVersionUID = 6190621106981774043L; | ||
| 90 | |||
| 91 | /** | ||
| 92 | * Create a check box menu item with an empty label. | ||
| 93 | * The item's state is initially set to "off." | ||
| 94 | * @exception HeadlessException if GraphicsEnvironment.isHeadless() | ||
| 95 | * returns true | ||
| 96 | * @see java.awt.GraphicsEnvironment#isHeadless | ||
| 97 | * @since JDK1.1 | ||
| 98 | */ | ||
| 99 | public CheckboxMenuItem() throws HeadlessException { | ||
| 100 | this("", false); | ||
| 101 | } | ||
| 102 | |||
| 103 | /** | ||
| 104 | * Create a check box menu item with the specified label. | ||
| 105 | * The item's state is initially set to "off." | ||
| 106 | |||
| 107 | * @param label a string label for the check box menu item, | ||
| 108 | * or <code>null</code> for an unlabeled menu item. | ||
| 109 | * @exception HeadlessException if GraphicsEnvironment.isHeadless() | ||
| 110 | * returns true | ||
| 111 | * @see java.awt.GraphicsEnvironment#isHeadless | ||
| 112 | */ | ||
| 113 | public CheckboxMenuItem(String label) throws HeadlessException { | ||
| 114 | this(label, false); | ||
| 115 | } | ||
| 116 | |||
| 117 | /** | ||
| 118 | * Create a check box menu item with the specified label and state. | ||
| 119 | * @param label a string label for the check box menu item, | ||
| 120 | * or <code>null</code> for an unlabeled menu item. | ||
| 121 | * @param state the initial state of the menu item, where | ||
| 122 | * <code>true</code> indicates "on" and | ||
| 123 | * <code>false</code> indicates "off." | ||
| 124 | * @exception HeadlessException if GraphicsEnvironment.isHeadless() | ||
| 125 | * returns true | ||
| 126 | * @see java.awt.GraphicsEnvironment#isHeadless | ||
| 127 | * @since JDK1.1 | ||
| 128 | */ | ||
| 129 | public CheckboxMenuItem(String label, boolean state) | ||
| 130 | throws HeadlessException { | ||
| 131 | super(label); | ||
| 132 | this.state = state; | ||
| 133 | } | ||
| 134 | |||
| 135 | /** | ||
| 136 | * Construct a name for this MenuComponent. Called by getName() when | ||
| 137 | * the name is null. | ||
| 138 | */ | ||
| 139 | String constructComponentName() { | ||
| 140 | synchronized (CheckboxMenuItem.class) { | ||
| 141 | return base + nameCounter++; | ||
| 142 | } | ||
| 143 | } | ||
| 144 | |||
| 145 | /** | ||
| 146 | * Creates the peer of the checkbox item. This peer allows us to | ||
| 147 | * change the look of the checkbox item without changing its | ||
| 148 | * functionality. | ||
| 149 | * Most applications do not call this method directly. | ||
| 150 | * @see java.awt.Toolkit#createCheckboxMenuItem(java.awt.CheckboxMenuItem) | ||
| 151 | * @see java.awt.Component#getToolkit() | ||
| 152 | */ | ||
| 153 | public void addNotify() { | ||
| 154 | synchronized (getTreeLock()) { | ||
| 155 | if (peer == null) | ||
| 156 | peer = Toolkit.getDefaultToolkit().createCheckboxMenuItem(this); | ||
| 157 | super.addNotify(); | ||
| 158 | } | ||
| 159 | } | ||
| 160 | |||
| 161 | /** | ||
| 162 | * Determines whether the state of this check box menu item | ||
| 163 | * is "on" or "off." | ||
| 164 | * | ||
| 165 | * @return the state of this check box menu item, where | ||
| 166 | * <code>true</code> indicates "on" and | ||
| 167 | * <code>false</code> indicates "off" | ||
| 168 | * @see #setState | ||
| 169 | */ | ||
| 170 | public boolean getState() { | ||
| 171 | return state; | ||
| 172 | } | ||
| 173 | |||
| 174 | /** | ||
| 175 | * Sets this check box menu item to the specifed state. | ||
| 176 | * The boolean value <code>true</code> indicates "on" while | ||
| 177 | * <code>false</code> indicates "off." | ||
| 178 | * | ||
| 179 | * <p>Note that this method should be primarily used to | ||
| 180 | * initialize the state of the check box menu item. | ||
| 181 | * Programmatically setting the state of the check box | ||
| 182 | * menu item will <i>not</i> trigger | ||
| 183 | * an <code>ItemEvent</code>. The only way to trigger an | ||
| 184 | * <code>ItemEvent</code> is by user interaction. | ||
| 185 | * | ||
| 186 | * @param b <code>true</code> if the check box | ||
| 187 | * menu item is on, otherwise <code>false</code> | ||
| 188 | * @see #getState | ||
| 189 | */ | ||
| 190 | public synchronized void setState(boolean b) { | ||
| 191 | state = b; | ||
| 192 | CheckboxMenuItemPeer peer = (CheckboxMenuItemPeer)this.peer; | ||
| 193 | if (peer != null) { | ||
| 194 | peer.setState(b); | ||
| 195 | } | ||
| 196 | } | ||
| 197 | |||
| 198 | /** | ||
| 199 | * Returns the an array (length 1) containing the checkbox menu item | ||
| 200 | * label or null if the checkbox is not selected. | ||
| 201 | * @see ItemSelectable | ||
| 202 | */ | ||
| 203 | public synchronized Object[] getSelectedObjects() { | ||
| 204 | if (state) { | ||
| 205 | Object[] items = new Object[1]; | ||
| 206 | items[0] = label; | ||
| 207 | return items; | ||
| 208 | } | ||
| 209 | return null; | ||
| 210 | } | ||
| 211 | |||
| 212 | /** | ||
| 213 | * Adds the specified item listener to receive item events from | ||
| 214 | * this check box menu item. Item events are sent in response to user | ||
| 215 | * actions, but not in response to calls to setState(). | ||
| 216 | * If l is null, no exception is thrown and no action is performed. | ||
| 217 | * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads" | ||
| 218 | * >AWT Threading Issues</a> for details on AWT's threading model. | ||
| 219 | * | ||
| 220 | * @param l the item listener | ||
| 221 | * @see #removeItemListener | ||
| 222 | * @see #getItemListeners | ||
| 223 | * @see #setState | ||
| 224 | * @see java.awt.event.ItemEvent | ||
| 225 | * @see java.awt.event.ItemListener | ||
| 226 | * @since JDK1.1 | ||
| 227 | */ | ||
| 228 | public synchronized void addItemListener(ItemListener l) { | ||
| 229 | if (l == null) { | ||
| 230 | return; | ||
| 231 | } | ||
| 232 | itemListener = AWTEventMulticaster.add(itemListener, l); | ||
| 233 | newEventsOnly = true; | ||
| 234 | } | ||
| 235 | |||
| 236 | /** | ||
| 237 | * Removes the specified item listener so that it no longer receives | ||
| 238 | * item events from this check box menu item. | ||
| 239 | * If l is null, no exception is thrown and no action is performed. | ||
| 240 | * <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads" | ||
| 241 | * >AWT Threading Issues</a> for details on AWT's threading model. | ||
| 242 | * | ||
| 243 | * @param l the item listener | ||
| 244 | * @see #addItemListener | ||
| 245 | * @see #getItemListeners | ||
| 246 | * @see java.awt.event.ItemEvent | ||
| 247 | * @see java.awt.event.ItemListener | ||
| 248 | * @since JDK1.1 | ||
| 249 | */ | ||
| 250 | public synchronized void removeItemListener(ItemListener l) { | ||
| 251 | if (l == null) { | ||
| 252 | return; | ||
| 253 | } | ||
| 254 | itemListener = AWTEventMulticaster.remove(itemListener, l); | ||
| 255 | } | ||
| 256 | |||
| 257 | /** | ||
| 258 | * Returns an array of all the item listeners | ||
| 259 | * registered on this checkbox menuitem. | ||
| 260 | * | ||
| 261 | * @return all of this checkbox menuitem's <code>ItemListener</code>s | ||
| 262 | * or an empty array if no item | ||
| 263 | * listeners are currently registered | ||
| 264 | * | ||
| 265 | * @see #addItemListener | ||
| 266 | * @see #removeItemListener | ||
| 267 | * @see java.awt.event.ItemEvent | ||
| 268 | * @see java.awt.event.ItemListener | ||
| 269 | * @since 1.4 | ||
| 270 | */ | ||
| 271 | public synchronized ItemListener[] getItemListeners() { | ||
| 272 | return (ItemListener[])(getListeners(ItemListener.class)); | ||
| 273 | } | ||
| 274 | |||
| 275 | /** | ||
| 276 | * Returns an array of all the objects currently registered | ||
| 277 | * as <code><em>Foo</em>Listener</code>s | ||
| 278 | * upon this <code>CheckboxMenuItem</code>. | ||
| 279 | * <code><em>Foo</em>Listener</code>s are registered using the | ||
| 280 | * <code>add<em>Foo</em>Listener</code> method. | ||
| 281 | * | ||
| 282 | * <p> | ||
| 283 | * You can specify the <code>listenerType</code> argument | ||
| 284 | * with a class literal, such as | ||
| 285 | * <code><em>Foo</em>Listener.class</code>. | ||
| 286 | * For example, you can query a | ||
| 287 | * <code>CheckboxMenuItem</code> <code>c</code> | ||
| 288 | * for its item listeners with the following code: | ||
| 289 | * | ||
| 290 | * <pre>ItemListener[] ils = (ItemListener[])(c.getListeners(ItemListener.class));</pre> | ||
| 291 | * | ||
| 292 | * If no such listeners exist, this method returns an empty array. | ||
| 293 | * | ||
| 294 | * @param listenerType the type of listeners requested; this parameter | ||
| 295 | * should specify an interface that descends from | ||
| 296 | * <code>java.util.EventListener</code> | ||
| 297 | * @return an array of all objects registered as | ||
| 298 | * <code><em>Foo</em>Listener</code>s on this checkbox menuitem, | ||
| 299 | * or an empty array if no such | ||
| 300 | * listeners have been added | ||
| 301 | * @exception ClassCastException if <code>listenerType</code> | ||
| 302 | * doesn't specify a class or interface that implements | ||
| 303 | * <code>java.util.EventListener</code> | ||
| 304 | * | ||
| 305 | * @see #getItemListeners | ||
| 306 | * @since 1.3 | ||
| 307 | */ | ||
| 308 | public <T extends EventListener> T[] getListeners(Class<T> listenerType) { | ||
| 309 | EventListener l = null; | ||
| 310 | if (listenerType == ItemListener.class) { | ||
| 311 | l = itemListener; | ||
| 312 | } else { | ||
| 313 | return super.getListeners(listenerType); | ||
| 314 | } | ||
| 315 | return AWTEventMulticaster.getListeners(l, listenerType); | ||
| 316 | } | ||
| 317 | |||
| 318 | // REMIND: remove when filtering is done at lower level | ||
| 319 | boolean eventEnabled(AWTEvent e) { | ||
| 320 | if (e.id == ItemEvent.ITEM_STATE_CHANGED) { | ||
| 321 | if ((eventMask & AWTEvent.ITEM_EVENT_MASK) != 0 || | ||
| 322 | itemListener != null) { | ||
| 323 | return true; | ||
| 324 | } | ||
| 325 | return false; | ||
| 326 | } | ||
| 327 | return super.eventEnabled(e); | ||
| 328 | } | ||
| 329 | |||
| 330 | /** | ||
| 331 | * Processes events on this check box menu item. | ||
| 332 | * If the event is an instance of <code>ItemEvent</code>, | ||
| 333 | * this method invokes the <code>processItemEvent</code> method. | ||
| 334 | * If the event is not an item event, | ||
| 335 | * it invokes <code>processEvent</code> on the superclass. | ||
| 336 | * <p> | ||
| 337 | * Check box menu items currently support only item events. | ||
| 338 | * <p>Note that if the event parameter is <code>null</code> | ||
| 339 | * the behavior is unspecified and may result in an | ||
| 340 | * exception. | ||
| 341 | * | ||
| 342 | * @param e the event | ||
| 343 | * @see java.awt.event.ItemEvent | ||
| 344 | * @see #processItemEvent | ||
| 345 | * @since JDK1.1 | ||
| 346 | */ | ||
| 347 | protected void processEvent(AWTEvent e) { | ||
| 348 | if (e instanceof ItemEvent) { | ||
| 349 | processItemEvent((ItemEvent)e); | ||
| 350 | return; | ||
| 351 | } | ||
| 352 | super.processEvent(e); | ||
| 353 | } | ||
| 354 | |||
| 355 | /** | ||
| 356 | * Processes item events occurring on this check box menu item by | ||
| 357 | * dispatching them to any registered <code>ItemListener</code> objects. | ||
| 358 | * <p> | ||
| 359 | * This method is not called unless item events are | ||
| 360 | * enabled for this menu item. Item events are enabled | ||
| 361 | * when one of the following occurs: | ||
| 362 | * <p><ul> | ||
| 363 | * <li>An <code>ItemListener</code> object is registered | ||
| 364 | * via <code>addItemListener</code>. | ||
| 365 | * <li>Item events are enabled via <code>enableEvents</code>. | ||
| 366 | * </ul> | ||
| 367 | * <p>Note that if the event parameter is <code>null</code> | ||
| 368 | * the behavior is unspecified and may result in an | ||
| 369 | * exception. | ||
| 370 | * | ||
| 371 | * @param e the item event | ||
| 372 | * @see java.awt.event.ItemEvent | ||
| 373 | * @see java.awt.event.ItemListener | ||
| 374 | * @see #addItemListener | ||
| 375 | * @see java.awt.MenuItem#enableEvents | ||
| 376 | * @since JDK1.1 | ||
| 377 | */ | ||
| 378 | protected void processItemEvent(ItemEvent e) { | ||
| 379 | ItemListener listener = itemListener; | ||
| 380 | if (listener != null) { | ||
| 381 | listener.itemStateChanged(e); | ||
| 382 | } | ||
| 383 | } | ||
| 384 | |||
| 385 | /* | ||
| 386 | * Post an ItemEvent and toggle state. | ||
| 387 | */ | ||
| 388 | void doMenuEvent(long when, int modifiers) { | ||
| 389 | setState(!state); | ||
| 390 | Toolkit.getEventQueue().postEvent( | ||
| 391 | new ItemEvent(this, ItemEvent.ITEM_STATE_CHANGED, | ||
| 392 | getLabel(), | ||
| 393 | state ? ItemEvent.SELECTED : | ||
| 394 | ItemEvent.DESELECTED)); | ||
| 395 | } | ||
| 396 | |||
| 397 | /** | ||
| 398 | * Returns a string representing the state of this | ||
| 399 | * <code>CheckBoxMenuItem</code>. This | ||
| 400 | * method is intended to be used only for debugging purposes, and the | ||
| 401 | * content and format of the returned string may vary between | ||
| 402 | * implementations. The returned string may be empty but may not be | ||
| 403 | * <code>null</code>. | ||
| 404 | * | ||
| 405 | * @return the parameter string of this check box menu item | ||
| 406 | */ | ||
| 407 | public String paramString() { | ||
| 408 | return super.paramString() + ",state=" + state; | ||
| 409 | } | ||
| 410 | |||
| 411 | /* Serialization support. | ||
| 412 | */ | ||
| 413 | |||
| 414 | /* | ||
| 415 | * Serial Data Version | ||
| 416 | * @serial | ||
| 417 | */ | ||
| 418 | private int checkboxMenuItemSerializedDataVersion = 1; | ||
| 419 | |||
| 420 | /** | ||
| 421 | * Writes default serializable fields to stream. Writes | ||
| 422 | * a list of serializable <code>ItemListeners</code> | ||
| 423 | * as optional data. The non-serializable | ||
| 424 | * <code>ItemListeners</code> are detected and | ||
| 425 | * no attempt is made to serialize them. | ||
| 426 | * | ||
| 427 | * @param s the <code>ObjectOutputStream</code> to write | ||
| 428 | * @serialData <code>null</code> terminated sequence of | ||
| 429 | * 0 or more pairs; the pair consists of a <code>String</code> | ||
| 430 | * and an <code>Object</code>; the <code>String</code> indicates | ||
| 431 | * the type of object and is one of the following: | ||
| 432 | * <code>itemListenerK</code> indicating an | ||
| 433 | * <code>ItemListener</code> object | ||
| 434 | * | ||
| 435 | * @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener) | ||
| 436 | * @see java.awt.Component#itemListenerK | ||
| 437 | * @see #readObject(ObjectInputStream) | ||
| 438 | */ | ||
| 439 | private void writeObject(ObjectOutputStream s) | ||
| 440 | throws java.io.IOException | ||
| 441 | { | ||
| 442 | s.defaultWriteObject(); | ||
| 443 | |||
| 444 | AWTEventMulticaster.save(s, itemListenerK, itemListener); | ||
| 445 | s.writeObject(null); | ||
| 446 | } | ||
| 447 | |||
| 448 | /* | ||
| 449 | * Reads the <code>ObjectInputStream</code> and if it | ||
| 450 | * isn't <code>null</code> adds a listener to receive | ||
| 451 | * item events fired by the <code>Checkbox</code> menu item. | ||
| 452 | * Unrecognized keys or values will be ignored. | ||
| 453 | * | ||
| 454 | * @param s the <code>ObjectInputStream</code> to read | ||
| 455 | * @serial | ||
| 456 | * @see removeActionListener() | ||
| 457 | * @see addActionListener() | ||
| 458 | * @see #writeObject | ||
| 459 | */ | ||
| 460 | private void readObject(ObjectInputStream s) | ||
| 461 | throws ClassNotFoundException, IOException | ||
| 462 | { | ||
| 463 | s.defaultReadObject(); | ||
| 464 | |||
| 465 | Object keyOrNull; | ||
| 466 | while(null != (keyOrNull = s.readObject())) { | ||
| 467 | String key = ((String)keyOrNull).intern(); | ||
| 468 | |||
| 469 | if (itemListenerK == key) | ||
| 470 | addItemListener((ItemListener)(s.readObject())); | ||
| 471 | |||
| 472 | else // skip value for unrecognized key | ||
| 473 | s.readObject(); | ||
| 474 | } | ||
| 475 | } | ||
| 476 | |||
| 477 | /** | ||
| 478 | * Initialize JNI field and method IDs | ||
| 479 | */ | ||
| 480 | private static native void initIDs(); | ||
| 481 | |||
| 482 | |||
| 483 | ///////////////// | ||
| 484 | // Accessibility support | ||
| 485 | //////////////// | ||
| 486 | |||
| 487 | /** | ||
| 488 | * Gets the AccessibleContext associated with this CheckboxMenuItem. | ||
| 489 | * For checkbox menu items, the AccessibleContext takes the | ||
| 490 | * form of an AccessibleAWTCheckboxMenuItem. | ||
| 491 | * A new AccessibleAWTCheckboxMenuItem is created if necessary. | ||
| 492 | * | ||
| 493 | * @return an AccessibleAWTCheckboxMenuItem that serves as the | ||
| 494 | * AccessibleContext of this CheckboxMenuItem | ||
| 495 | * @since 1.3 | ||
| 496 | */ | ||
| 497 | public AccessibleContext getAccessibleContext() { | ||
| 498 | if (accessibleContext == null) { | ||
| 499 | accessibleContext = new AccessibleAWTCheckboxMenuItem(); | ||
| 500 | } | ||
| 501 | return accessibleContext; | ||
| 502 | } | ||
| 503 | |||
| 504 | /** | ||
| 505 | * Inner class of CheckboxMenuItem used to provide default support for | ||
| 506 | * accessibility. This class is not meant to be used directly by | ||
| 507 | * application developers, but is instead meant only to be | ||
| 508 | * subclassed by menu component developers. | ||
| 509 | * <p> | ||
| 510 | * This class implements accessibility support for the | ||
| 511 | * <code>CheckboxMenuItem</code> class. It provides an implementation | ||
| 512 | * of the Java Accessibility API appropriate to checkbox menu item | ||
| 513 | * user-interface elements. | ||
| 514 | * @since 1.3 | ||
| 515 | */ | ||
| 516 | protected class AccessibleAWTCheckboxMenuItem extends AccessibleAWTMenuItem | ||
| 517 | implements AccessibleAction, AccessibleValue | ||
| 518 | { | ||
| 519 | /* | ||
| 520 | * JDK 1.3 serialVersionUID | ||
| 521 | */ | ||
| 522 | private static final long serialVersionUID = -1122642964303476L; | ||
| 523 | |||
| 524 | /** | ||
| 525 | * Get the AccessibleAction associated with this object. In the | ||
| 526 | * implementation of the Java Accessibility API for this class, | ||
| 527 | * return this object, which is responsible for implementing the | ||
| 528 | * AccessibleAction interface on behalf of itself. | ||
| 529 | * | ||
| 530 | * @return this object | ||
| 531 | */ | ||
| 532 | public AccessibleAction getAccessibleAction() { | ||
| 533 | return this; | ||
| 534 | } | ||
| 535 | |||
| 536 | /** | ||
| 537 | * Get the AccessibleValue associated with this object. In the | ||
| 538 | * implementation of the Java Accessibility API for this class, | ||
| 539 | * return this object, which is responsible for implementing the | ||
| 540 | * AccessibleValue interface on behalf of itself. | ||
| 541 | * | ||
| 542 | * @return this object | ||
| 543 | */ | ||
| 544 | public AccessibleValue getAccessibleValue() { | ||
| 545 | return this; | ||
| 546 | } | ||
| 547 | |||
| 548 | /** | ||
| 549 | * Returns the number of Actions available in this object. | ||
| 550 | * If there is more than one, the first one is the "default" | ||
| 551 | * action. | ||
| 552 | * | ||
| 553 | * @return the number of Actions in this object | ||
| 554 | */ | ||
| 555 | public int getAccessibleActionCount() { | ||
| 556 | return 0; // To be fully implemented in a future release | ||
| 557 | } | ||
| 558 | |||
| 559 | /** | ||
| 560 | * Return a description of the specified action of the object. | ||
| 561 | * | ||
| 562 | * @param i zero-based index of the actions | ||
| 563 | */ | ||
| 564 | public String getAccessibleActionDescription(int i) { | ||
| 565 | return null; // To be fully implemented in a future release | ||
| 566 | } | ||
| 567 | |||
| 568 | /** | ||
| 569 | * Perform the specified Action on the object | ||
| 570 | * | ||
| 571 | * @param i zero-based index of actions | ||
| 572 | * @return true if the action was performed; otherwise false. | ||
| 573 | */ | ||
| 574 | public boolean doAccessibleAction(int i) { | ||
| 575 | return false; // To be fully implemented in a future release | ||
| 576 | } | ||
| 577 | |||
| 578 | /** | ||
| 579 | * Get the value of this object as a Number. If the value has not been | ||
| 580 | * set, the return value will be null. | ||
| 581 | * | ||
| 582 | * @return value of the object | ||
| 583 | * @see #setCurrentAccessibleValue | ||
| 584 | */ | ||
| 585 | public Number getCurrentAccessibleValue() { | ||
| 586 | return null; // To be fully implemented in a future release | ||
| 587 | } | ||
| 588 | |||
| 589 | /** | ||
| 590 | * Set the value of this object as a Number. | ||
| 591 | * | ||
| 592 | * @return true if the value was set; otherwise false | ||
| 593 | * @see #getCurrentAccessibleValue | ||
| 594 | */ | ||
| 595 | public boolean setCurrentAccessibleValue(Number n) { | ||
| 596 | return false; // To be fully implemented in a future release | ||
| 597 | } | ||
| 598 | |||
| 599 | /** | ||
| 600 | * Get the minimum value of this object as a Number. | ||
| 601 | * | ||
| 602 | * @return Minimum value of the object; null if this object does not | ||
| 603 | * have a minimum value | ||
| 604 | * @see #getMaximumAccessibleValue | ||
| 605 | */ | ||
| 606 | public Number getMinimumAccessibleValue() { | ||
| 607 | return null; // To be fully implemented in a future release | ||
| 608 | } | ||
| 609 | |||
| 610 | /** | ||
| 611 | * Get the maximum value of this object as a Number. | ||
| 612 | * | ||
| 613 | * @return Maximum value of the object; null if this object does not | ||
| 614 | * have a maximum value | ||
| 615 | * @see #getMinimumAccessibleValue | ||
| 616 | */ | ||
| 617 | public Number getMaximumAccessibleValue() { | ||
| 618 | return null; // To be fully implemented in a future release | ||
| 619 | } | ||
| 620 | |||
| 621 | /** | ||
| 622 | * Get the role of this object. | ||
| 623 | * | ||
| 624 | * @return an instance of AccessibleRole describing the role of the | ||
| 625 | * object | ||
| 626 | */ | ||
| 627 | public AccessibleRole getAccessibleRole() { | ||
| 628 | return AccessibleRole.CHECK_BOX; | ||
| 629 | } | ||
| 630 | |||
| 631 | } // class AccessibleAWTMenuItem | ||
| 632 | |||
| 633 | } | ||