1 /* 2 * Copyright (c) 1995, 2011, 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.MenuComponentPeer; 28 import java.awt.event.ActionEvent; 29 import java.io.IOException; 30 import java.io.ObjectInputStream; 31 import sun.awt.AppContext; 32 import sun.awt.SunToolkit; 33 import sun.awt.AWTAccessor; 34 import javax.accessibility.*; 35 36 import java.security.AccessControlContext; 37 import java.security.AccessController; 38 39 /** 40 * The abstract class <code>MenuComponent</code> is the superclass 41 * of all menu-related components. In this respect, the class 42 * <code>MenuComponent</code> is analogous to the abstract superclass 43 * <code>Component</code> for AWT components. 44 * <p> 45 * Menu components receive and process AWT events, just as components do, 46 * through the method <code>processEvent</code>. 47 * 48 * @author Arthur van Hoff 49 * @since JDK1.0 50 */ 51 public abstract class MenuComponent implements java.io.Serializable { 52 53 static { 54 /* ensure that the necessary native libraries are loaded */ 55 Toolkit.loadLibraries(); 56 if (!GraphicsEnvironment.isHeadless()) { 57 initIDs(); 58 } 59 } 60 61 transient MenuComponentPeer peer; 62 transient MenuContainer parent; 63 64 /** 65 * The <code>AppContext</code> of the <code>MenuComponent</code>. 66 * This is set in the constructor and never changes. 67 */ 68 transient AppContext appContext; 69 70 /** 71 * The menu component's font. This value can be 72 * <code>null</code> at which point a default will be used. 73 * This defaults to <code>null</code>. 74 * 75 * @serial 76 * @see #setFont(Font) 77 * @see #getFont() 78 */ 79 Font font; 80 81 /** 82 * The menu component's name, which defaults to <code>null</code>. 83 * @serial 84 * @see #getName() 85 * @see #setName(String) 86 */ 87 private String name; 88 89 /** 90 * A variable to indicate whether a name is explicitly set. 91 * If <code>true</code> the name will be set explicitly. 92 * This defaults to <code>false</code>. 93 * @serial 94 * @see #setName(String) 95 */ 96 private boolean nameExplicitlySet = false; 97 98 /** 99 * Defaults to <code>false</code>. 100 * @serial 101 * @see #dispatchEvent(AWTEvent) 102 */ 103 boolean newEventsOnly = false; 104 105 /* 106 * The menu's AccessControlContext. 107 */ 108 private transient volatile AccessControlContext acc = 109 AccessController.getContext(); 110 111 /* 112 * Returns the acc this menu component was constructed with. 113 */ 114 final AccessControlContext getAccessControlContext() { 115 if (acc == null) { 116 throw new SecurityException( 117 "MenuComponent is missing AccessControlContext"); 118 } 119 return acc; 120 } 121 122 /* 123 * Internal constants for serialization. 124 */ 125 final static String actionListenerK = Component.actionListenerK; 126 final static String itemListenerK = Component.itemListenerK; 127 128 /* 129 * JDK 1.1 serialVersionUID 130 */ 131 private static final long serialVersionUID = -4536902356223894379L; 132 133 static { 134 AWTAccessor.setMenuComponentAccessor( 135 new AWTAccessor.MenuComponentAccessor() { 136 public AppContext getAppContext(MenuComponent menuComp) { 137 return menuComp.appContext; 138 } 139 public void setAppContext(MenuComponent menuComp, 140 AppContext appContext) { 141 menuComp.appContext = appContext; 142 } 143 public MenuContainer getParent(MenuComponent menuComp) { 144 return menuComp.parent; 145 } 146 }); 147 } 148 149 /** 150 * Creates a <code>MenuComponent</code>. 151 * @exception HeadlessException if 152 * <code>GraphicsEnvironment.isHeadless</code> 153 * returns <code>true</code> 154 * @see java.awt.GraphicsEnvironment#isHeadless 155 */ 156 public MenuComponent() throws HeadlessException { 157 GraphicsEnvironment.checkHeadless(); 158 appContext = AppContext.getAppContext(); 159 } 160 161 /** 162 * Constructs a name for this <code>MenuComponent</code>. 163 * Called by <code>getName</code> when the name is <code>null</code>. 164 * @return a name for this <code>MenuComponent</code> 165 */ 166 String constructComponentName() { 167 return null; // For strict compliance with prior platform versions, a MenuComponent 168 // that doesn't set its name should return null from 169 // getName() 170 } 171 172 /** 173 * Gets the name of the menu component. 174 * @return the name of the menu component 175 * @see java.awt.MenuComponent#setName(java.lang.String) 176 * @since JDK1.1 177 */ 178 public String getName() { 179 if (name == null && !nameExplicitlySet) { 180 synchronized(this) { 181 if (name == null && !nameExplicitlySet) 182 name = constructComponentName(); 183 } 184 } 185 return name; 186 } 187 188 /** 189 * Sets the name of the component to the specified string. 190 * @param name the name of the menu component 191 * @see java.awt.MenuComponent#getName 192 * @since JDK1.1 193 */ 194 public void setName(String name) { 195 synchronized(this) { 196 this.name = name; 197 nameExplicitlySet = true; 198 } 199 } 200 201 /** 202 * Returns the parent container for this menu component. 203 * @return the menu component containing this menu component, 204 * or <code>null</code> if this menu component 205 * is the outermost component, the menu bar itself 206 */ 207 public MenuContainer getParent() { 208 return getParent_NoClientCode(); 209 } 210 // NOTE: This method may be called by privileged threads. 211 // This functionality is implemented in a package-private method 212 // to insure that it cannot be overridden by client subclasses. 213 // DO NOT INVOKE CLIENT CODE ON THIS THREAD! 214 final MenuContainer getParent_NoClientCode() { 215 return parent; 216 } 217 218 /** 219 * @deprecated As of JDK version 1.1, 220 * programs should not directly manipulate peers. 221 */ 222 @Deprecated 223 public MenuComponentPeer getPeer() { 224 return peer; 225 } 226 227 /** 228 * Gets the font used for this menu component. 229 * @return the font used in this menu component, if there is one; 230 * <code>null</code> otherwise 231 * @see java.awt.MenuComponent#setFont 232 */ 233 public Font getFont() { 234 Font font = this.font; 235 if (font != null) { 236 return font; 237 } 238 MenuContainer parent = this.parent; 239 if (parent != null) { 240 return parent.getFont(); 241 } 242 return null; 243 } 244 245 // NOTE: This method may be called by privileged threads. 246 // This functionality is implemented in a package-private method 247 // to insure that it cannot be overridden by client subclasses. 248 // DO NOT INVOKE CLIENT CODE ON THIS THREAD! 249 final Font getFont_NoClientCode() { 250 Font font = this.font; 251 if (font != null) { 252 return font; 253 } 254 255 // The MenuContainer interface does not have getFont_NoClientCode() 256 // and it cannot, because it must be package-private. Because of 257 // this, we must manually cast classes that implement 258 // MenuContainer. 259 Object parent = this.parent; 260 if (parent != null) { 261 if (parent instanceof Component) { 262 font = ((Component)parent).getFont_NoClientCode(); 263 } else if (parent instanceof MenuComponent) { 264 font = ((MenuComponent)parent).getFont_NoClientCode(); 265 } 266 } 267 return font; 268 } // getFont_NoClientCode() 269 270 271 /** 272 * Sets the font to be used for this menu component to the specified 273 * font. This font is also used by all subcomponents of this menu 274 * component, unless those subcomponents specify a different font. 275 * <p> 276 * Some platforms may not support setting of all font attributes 277 * of a menu component; in such cases, calling <code>setFont</code> 278 * will have no effect on the unsupported font attributes of this 279 * menu component. Unless subcomponents of this menu component 280 * specify a different font, this font will be used by those 281 * subcomponents if supported by the underlying platform. 282 * 283 * @param f the font to be set 284 * @see #getFont 285 * @see Font#getAttributes 286 * @see java.awt.font.TextAttribute 287 */ 288 public void setFont(Font f) { 289 font = f; 290 //Fixed 6312943: NullPointerException in method MenuComponent.setFont(Font) 291 MenuComponentPeer peer = (MenuComponentPeer)this.peer; 292 if (peer != null) { 293 peer.setFont(f); 294 } 295 } 296 297 /** 298 * Removes the menu component's peer. The peer allows us to modify the 299 * appearance of the menu component without changing the functionality of 300 * the menu component. 301 */ 302 public void removeNotify() { 303 synchronized (getTreeLock()) { 304 MenuComponentPeer p = (MenuComponentPeer)this.peer; 305 if (p != null) { 306 Toolkit.getEventQueue().removeSourceEvents(this, true); 307 this.peer = null; 308 p.dispose(); 309 } 310 } 311 } 312 313 /** 314 * Posts the specified event to the menu. 315 * This method is part of the Java 1.0 event system 316 * and it is maintained only for backwards compatibility. 317 * Its use is discouraged, and it may not be supported 318 * in the future. 319 * @param evt the event which is to take place 320 * @deprecated As of JDK version 1.1, replaced by {@link 321 * #dispatchEvent(AWTEvent) dispatchEvent}. 322 */ 323 @Deprecated 324 public boolean postEvent(Event evt) { 325 MenuContainer parent = this.parent; 326 if (parent != null) { 327 parent.postEvent(evt); 328 } 329 return false; 330 } 331 332 /** 333 * Delivers an event to this component or one of its sub components. 334 * @param e the event 335 */ 336 public final void dispatchEvent(AWTEvent e) { 337 dispatchEventImpl(e); 338 } 339 340 void dispatchEventImpl(AWTEvent e) { 341 EventQueue.setCurrentEventAndMostRecentTime(e); 342 343 Toolkit.getDefaultToolkit().notifyAWTEventListeners(e); 344 345 if (newEventsOnly || 346 (parent != null && parent instanceof MenuComponent && 347 ((MenuComponent)parent).newEventsOnly)) { 348 if (eventEnabled(e)) { 349 processEvent(e); 350 } else if (e instanceof ActionEvent && parent != null) { 351 e.setSource(parent); 352 ((MenuComponent)parent).dispatchEvent(e); 353 } 354 355 } else { // backward compatibility 356 Event olde = e.convertToOld(); 357 if (olde != null) { 358 postEvent(olde); 359 } 360 } 361 } 362 363 // REMIND: remove when filtering is done at lower level 364 boolean eventEnabled(AWTEvent e) { 365 return false; 366 } 367 /** 368 * Processes events occurring on this menu component. 369 * <p>Note that if the event parameter is <code>null</code> 370 * the behavior is unspecified and may result in an 371 * exception. 372 * 373 * @param e the event 374 * @since JDK1.1 375 */ 376 protected void processEvent(AWTEvent e) { 377 } 378 379 /** 380 * Returns a string representing the state of this 381 * <code>MenuComponent</code>. This method is intended to be used 382 * only for debugging purposes, and the content and format of the 383 * returned string may vary between implementations. The returned 384 * string may be empty but may not be <code>null</code>. 385 * 386 * @return the parameter string of this menu component 387 */ 388 protected String paramString() { 389 String thisName = getName(); 390 return (thisName != null? thisName : ""); 391 } 392 393 /** 394 * Returns a representation of this menu component as a string. 395 * @return a string representation of this menu component 396 */ 397 public String toString() { 398 return getClass().getName() + "[" + paramString() + "]"; 399 } 400 401 /** 402 * Gets this component's locking object (the object that owns the thread 403 * sychronization monitor) for AWT component-tree and layout 404 * operations. 405 * @return this component's locking object 406 */ 407 protected final Object getTreeLock() { 408 return Component.LOCK; 409 } 410 411 /** 412 * Reads the menu component from an object input stream. 413 * 414 * @param s the <code>ObjectInputStream</code> to read 415 * @exception HeadlessException if 416 * <code>GraphicsEnvironment.isHeadless</code> returns 417 * <code>true</code> 418 * @serial 419 * @see java.awt.GraphicsEnvironment#isHeadless 420 */ 421 private void readObject(ObjectInputStream s) 422 throws ClassNotFoundException, IOException, HeadlessException 423 { 424 GraphicsEnvironment.checkHeadless(); 425 426 acc = AccessController.getContext(); 427 428 s.defaultReadObject(); 429 430 appContext = AppContext.getAppContext(); 431 } 432 433 /** 434 * Initialize JNI field and method IDs. 435 */ 436 private static native void initIDs(); 437 438 439 /* 440 * --- Accessibility Support --- 441 * 442 * MenuComponent will contain all of the methods in interface Accessible, 443 * though it won't actually implement the interface - that will be up 444 * to the individual objects which extend MenuComponent. 445 */ 446 447 AccessibleContext accessibleContext = null; 448 449 /** 450 * Gets the <code>AccessibleContext</code> associated with 451 * this <code>MenuComponent</code>. 452 * 453 * The method implemented by this base class returns <code>null</code>. 454 * Classes that extend <code>MenuComponent</code> 455 * should implement this method to return the 456 * <code>AccessibleContext</code> associated with the subclass. 457 * 458 * @return the <code>AccessibleContext</code> of this 459 * <code>MenuComponent</code> 460 * @since 1.3 461 */ 462 public AccessibleContext getAccessibleContext() { 463 return accessibleContext; 464 } 465 466 /** 467 * Inner class of <code>MenuComponent</code> used to provide 468 * default support for accessibility. This class is not meant 469 * to be used directly by application developers, but is instead 470 * meant only to be subclassed by menu component developers. 471 * <p> 472 * The class used to obtain the accessible role for this object. 473 * @since 1.3 474 */ 475 protected abstract class AccessibleAWTMenuComponent 476 extends AccessibleContext 477 implements java.io.Serializable, AccessibleComponent, 478 AccessibleSelection 479 { 480 /* 481 * JDK 1.3 serialVersionUID 482 */ 483 private static final long serialVersionUID = -4269533416223798698L; 484 485 /** 486 * Although the class is abstract, this should be called by 487 * all sub-classes. 488 */ 489 protected AccessibleAWTMenuComponent() { 490 } 491 492 // AccessibleContext methods 493 // 494 495 /** 496 * Gets the <code>AccessibleSelection</code> associated with this 497 * object which allows its <code>Accessible</code> children to be selected. 498 * 499 * @return <code>AccessibleSelection</code> if supported by object; 500 * else return <code>null</code> 501 * @see AccessibleSelection 502 */ 503 public AccessibleSelection getAccessibleSelection() { 504 return this; 505 } 506 507 /** 508 * Gets the accessible name of this object. This should almost never 509 * return <code>java.awt.MenuComponent.getName</code>, as that 510 * generally isn't a localized name, and doesn't have meaning for the 511 * user. If the object is fundamentally a text object (e.g. a menu item), the 512 * accessible name should be the text of the object (e.g. "save"). 513 * If the object has a tooltip, the tooltip text may also be an 514 * appropriate String to return. 515 * 516 * @return the localized name of the object -- can be <code>null</code> 517 * if this object does not have a name 518 * @see AccessibleContext#setAccessibleName 519 */ 520 public String getAccessibleName() { 521 return accessibleName; 522 } 523 524 /** 525 * Gets the accessible description of this object. This should be 526 * a concise, localized description of what this object is - what 527 * is its meaning to the user. If the object has a tooltip, the 528 * tooltip text may be an appropriate string to return, assuming 529 * it contains a concise description of the object (instead of just 530 * the name of the object - e.g. a "Save" icon on a toolbar that 531 * had "save" as the tooltip text shouldn't return the tooltip 532 * text as the description, but something like "Saves the current 533 * text document" instead). 534 * 535 * @return the localized description of the object -- can be 536 * <code>null</code> if this object does not have a description 537 * @see AccessibleContext#setAccessibleDescription 538 */ 539 public String getAccessibleDescription() { 540 return accessibleDescription; 541 } 542 543 /** 544 * Gets the role of this object. 545 * 546 * @return an instance of <code>AccessibleRole</code> 547 * describing the role of the object 548 * @see AccessibleRole 549 */ 550 public AccessibleRole getAccessibleRole() { 551 return AccessibleRole.AWT_COMPONENT; // Non-specific -- overridden in subclasses 552 } 553 554 /** 555 * Gets the state of this object. 556 * 557 * @return an instance of <code>AccessibleStateSet</code> 558 * containing the current state set of the object 559 * @see AccessibleState 560 */ 561 public AccessibleStateSet getAccessibleStateSet() { 562 return MenuComponent.this.getAccessibleStateSet(); 563 } 564 565 /** 566 * Gets the <code>Accessible</code> parent of this object. 567 * If the parent of this object implements <code>Accessible</code>, 568 * this method should simply return <code>getParent</code>. 569 * 570 * @return the <code>Accessible</code> parent of this object -- can 571 * be <code>null</code> if this object does not have an 572 * <code>Accessible</code> parent 573 */ 574 public Accessible getAccessibleParent() { 575 if (accessibleParent != null) { 576 return accessibleParent; 577 } else { 578 MenuContainer parent = MenuComponent.this.getParent(); 579 if (parent instanceof Accessible) { 580 return (Accessible) parent; 581 } 582 } 583 return null; 584 } 585 586 /** 587 * Gets the index of this object in its accessible parent. 588 * 589 * @return the index of this object in its parent; -1 if this 590 * object does not have an accessible parent 591 * @see #getAccessibleParent 592 */ 593 public int getAccessibleIndexInParent() { 594 return MenuComponent.this.getAccessibleIndexInParent(); 595 } 596 597 /** 598 * Returns the number of accessible children in the object. If all 599 * of the children of this object implement <code>Accessible</code>, 600 * then this method should return the number of children of this object. 601 * 602 * @return the number of accessible children in the object 603 */ 604 public int getAccessibleChildrenCount() { 605 return 0; // MenuComponents don't have children 606 } 607 608 /** 609 * Returns the nth <code>Accessible</code> child of the object. 610 * 611 * @param i zero-based index of child 612 * @return the nth Accessible child of the object 613 */ 614 public Accessible getAccessibleChild(int i) { 615 return null; // MenuComponents don't have children 616 } 617 618 /** 619 * Returns the locale of this object. 620 * 621 * @return the locale of this object 622 */ 623 public java.util.Locale getLocale() { 624 MenuContainer parent = MenuComponent.this.getParent(); 625 if (parent instanceof Component) 626 return ((Component)parent).getLocale(); 627 else 628 return java.util.Locale.getDefault(); 629 } 630 631 /** 632 * Gets the <code>AccessibleComponent</code> associated with 633 * this object if one exists. Otherwise return <code>null</code>. 634 * 635 * @return the component 636 */ 637 public AccessibleComponent getAccessibleComponent() { 638 return this; 639 } 640 641 642 // AccessibleComponent methods 643 // 644 /** 645 * Gets the background color of this object. 646 * 647 * @return the background color, if supported, of the object; 648 * otherwise, <code>null</code> 649 */ 650 public Color getBackground() { 651 return null; // Not supported for MenuComponents 652 } 653 654 /** 655 * Sets the background color of this object. 656 * (For transparency, see <code>isOpaque</code>.) 657 * 658 * @param c the new <code>Color</code> for the background 659 * @see Component#isOpaque 660 */ 661 public void setBackground(Color c) { 662 // Not supported for MenuComponents 663 } 664 665 /** 666 * Gets the foreground color of this object. 667 * 668 * @return the foreground color, if supported, of the object; 669 * otherwise, <code>null</code> 670 */ 671 public Color getForeground() { 672 return null; // Not supported for MenuComponents 673 } 674 675 /** 676 * Sets the foreground color of this object. 677 * 678 * @param c the new <code>Color</code> for the foreground 679 */ 680 public void setForeground(Color c) { 681 // Not supported for MenuComponents 682 } 683 684 /** 685 * Gets the <code>Cursor</code> of this object. 686 * 687 * @return the <code>Curso</code>, if supported, of the object; 688 * otherwise, <code>null</code> 689 */ 690 public Cursor getCursor() { 691 return null; // Not supported for MenuComponents 692 } 693 694 /** 695 * Sets the <code>Cursor</code> of this object. 696 * <p> 697 * The method may have no visual effect if the Java platform 698 * implementation and/or the native system do not support 699 * changing the mouse cursor shape. 700 * @param cursor the new <code>Cursor</code> for the object 701 */ 702 public void setCursor(Cursor cursor) { 703 // Not supported for MenuComponents 704 } 705 706 /** 707 * Gets the <code>Font</code> of this object. 708 * 709 * @return the <code>Font</code>,if supported, for the object; 710 * otherwise, <code>null</code> 711 */ 712 public Font getFont() { 713 return MenuComponent.this.getFont(); 714 } 715 716 /** 717 * Sets the <code>Font</code> of this object. 718 * 719 * @param f the new <code>Font</code> for the object 720 */ 721 public void setFont(Font f) { 722 MenuComponent.this.setFont(f); 723 } 724 725 /** 726 * Gets the <code>FontMetrics</code> of this object. 727 * 728 * @param f the <code>Font</code> 729 * @return the FontMetrics, if supported, the object; 730 * otherwise, <code>null</code> 731 * @see #getFont 732 */ 733 public FontMetrics getFontMetrics(Font f) { 734 return null; // Not supported for MenuComponents 735 } 736 737 /** 738 * Determines if the object is enabled. 739 * 740 * @return true if object is enabled; otherwise, false 741 */ 742 public boolean isEnabled() { 743 return true; // Not supported for MenuComponents 744 } 745 746 /** 747 * Sets the enabled state of the object. 748 * 749 * @param b if true, enables this object; otherwise, disables it 750 */ 751 public void setEnabled(boolean b) { 752 // Not supported for MenuComponents 753 } 754 755 /** 756 * Determines if the object is visible. Note: this means that the 757 * object intends to be visible; however, it may not in fact be 758 * showing on the screen because one of the objects that this object 759 * is contained by is not visible. To determine if an object is 760 * showing on the screen, use <code>isShowing</code>. 761 * 762 * @return true if object is visible; otherwise, false 763 */ 764 public boolean isVisible() { 765 return true; // Not supported for MenuComponents 766 } 767 768 /** 769 * Sets the visible state of the object. 770 * 771 * @param b if true, shows this object; otherwise, hides it 772 */ 773 public void setVisible(boolean b) { 774 // Not supported for MenuComponents 775 } 776 777 /** 778 * Determines if the object is showing. This is determined by checking 779 * the visibility of the object and ancestors of the object. Note: 780 * this will return true even if the object is obscured by another 781 * (for example, it happens to be underneath a menu that was pulled 782 * down). 783 * 784 * @return true if object is showing; otherwise, false 785 */ 786 public boolean isShowing() { 787 return true; // Not supported for MenuComponents 788 } 789 790 /** 791 * Checks whether the specified point is within this object's bounds, 792 * where the point's x and y coordinates are defined to be relative to 793 * the coordinate system of the object. 794 * 795 * @param p the <code>Point</code> relative to the coordinate 796 * system of the object 797 * @return true if object contains <code>Point</code>; otherwise false 798 */ 799 public boolean contains(Point p) { 800 return false; // Not supported for MenuComponents 801 } 802 803 /** 804 * Returns the location of the object on the screen. 805 * 806 * @return location of object on screen -- can be <code>null</code> 807 * if this object is not on the screen 808 */ 809 public Point getLocationOnScreen() { 810 return null; // Not supported for MenuComponents 811 } 812 813 /** 814 * Gets the location of the object relative to the parent in the form 815 * of a point specifying the object's top-left corner in the screen's 816 * coordinate space. 817 * 818 * @return an instance of <code>Point</code> representing the 819 * top-left corner of the object's bounds in the coordinate 820 * space of the screen; <code>null</code> if 821 * this object or its parent are not on the screen 822 */ 823 public Point getLocation() { 824 return null; // Not supported for MenuComponents 825 } 826 827 /** 828 * Sets the location of the object relative to the parent. 829 */ 830 public void setLocation(Point p) { 831 // Not supported for MenuComponents 832 } 833 834 /** 835 * Gets the bounds of this object in the form of a 836 * <code>Rectangle</code> object. 837 * The bounds specify this object's width, height, and location 838 * relative to its parent. 839 * 840 * @return a rectangle indicating this component's bounds; 841 * <code>null</code> if this object is not on the screen 842 */ 843 public Rectangle getBounds() { 844 return null; // Not supported for MenuComponents 845 } 846 847 /** 848 * Sets the bounds of this object in the form of a 849 * <code>Rectangle</code> object. 850 * The bounds specify this object's width, height, and location 851 * relative to its parent. 852 * 853 * @param r a rectangle indicating this component's bounds 854 */ 855 public void setBounds(Rectangle r) { 856 // Not supported for MenuComponents 857 } 858 859 /** 860 * Returns the size of this object in the form of a 861 * <code>Dimension</code> object. The height field of 862 * the <code>Dimension</code> object contains this object's 863 * height, and the width field of the <code>Dimension</code> 864 * object contains this object's width. 865 * 866 * @return a <code>Dimension</code> object that indicates the 867 * size of this component; <code>null</code> 868 * if this object is not on the screen 869 */ 870 public Dimension getSize() { 871 return null; // Not supported for MenuComponents 872 } 873 874 /** 875 * Resizes this object. 876 * 877 * @param d - the <code>Dimension</code> specifying the 878 * new size of the object 879 */ 880 public void setSize(Dimension d) { 881 // Not supported for MenuComponents 882 } 883 884 /** 885 * Returns the <code>Accessible</code> child, if one exists, 886 * contained at the local coordinate <code>Point</code>. 887 * If there is no <code>Accessible</code> child, <code>null</code> 888 * is returned. 889 * 890 * @param p the point defining the top-left corner of the 891 * <code>Accessible</code>, given in the coordinate space 892 * of the object's parent 893 * @return the <code>Accessible</code>, if it exists, 894 * at the specified location; else <code>null</code> 895 */ 896 public Accessible getAccessibleAt(Point p) { 897 return null; // MenuComponents don't have children 898 } 899 900 /** 901 * Returns whether this object can accept focus or not. 902 * 903 * @return true if object can accept focus; otherwise false 904 */ 905 public boolean isFocusTraversable() { 906 return true; // Not supported for MenuComponents 907 } 908 909 /** 910 * Requests focus for this object. 911 */ 912 public void requestFocus() { 913 // Not supported for MenuComponents 914 } 915 916 /** 917 * Adds the specified focus listener to receive focus events from this 918 * component. 919 * 920 * @param l the focus listener 921 */ 922 public void addFocusListener(java.awt.event.FocusListener l) { 923 // Not supported for MenuComponents 924 } 925 926 /** 927 * Removes the specified focus listener so it no longer receives focus 928 * events from this component. 929 * 930 * @param l the focus listener 931 */ 932 public void removeFocusListener(java.awt.event.FocusListener l) { 933 // Not supported for MenuComponents 934 } 935 936 // AccessibleSelection methods 937 // 938 939 /** 940 * Returns the number of <code>Accessible</code> children currently selected. 941 * If no children are selected, the return value will be 0. 942 * 943 * @return the number of items currently selected 944 */ 945 public int getAccessibleSelectionCount() { 946 return 0; // To be fully implemented in a future release 947 } 948 949 /** 950 * Returns an <code>Accessible</code> representing the specified 951 * selected child in the object. If there isn't a selection, or there are 952 * fewer children selected than the integer passed in, the return 953 * value will be <code>null</code>. 954 * <p>Note that the index represents the i-th selected child, which 955 * is different from the i-th child. 956 * 957 * @param i the zero-based index of selected children 958 * @return the i-th selected child 959 * @see #getAccessibleSelectionCount 960 */ 961 public Accessible getAccessibleSelection(int i) { 962 return null; // To be fully implemented in a future release 963 } 964 965 /** 966 * Determines if the current child of this object is selected. 967 * 968 * @return true if the current child of this object is selected; 969 * else false 970 * @param i the zero-based index of the child in this 971 * <code>Accessible</code> object 972 * @see AccessibleContext#getAccessibleChild 973 */ 974 public boolean isAccessibleChildSelected(int i) { 975 return false; // To be fully implemented in a future release 976 } 977 978 /** 979 * Adds the specified <code>Accessible</code> child of the object 980 * to the object's selection. If the object supports multiple selections, 981 * the specified child is added to any existing selection, otherwise 982 * it replaces any existing selection in the object. If the 983 * specified child is already selected, this method has no effect. 984 * 985 * @param i the zero-based index of the child 986 * @see AccessibleContext#getAccessibleChild 987 */ 988 public void addAccessibleSelection(int i) { 989 // To be fully implemented in a future release 990 } 991 992 /** 993 * Removes the specified child of the object from the object's 994 * selection. If the specified item isn't currently selected, this 995 * method has no effect. 996 * 997 * @param i the zero-based index of the child 998 * @see AccessibleContext#getAccessibleChild 999 */ 1000 public void removeAccessibleSelection(int i) { 1001 // To be fully implemented in a future release 1002 } 1003 1004 /** 1005 * Clears the selection in the object, so that no children in the 1006 * object are selected. 1007 */ 1008 public void clearAccessibleSelection() { 1009 // To be fully implemented in a future release 1010 } 1011 1012 /** 1013 * Causes every child of the object to be selected 1014 * if the object supports multiple selections. 1015 */ 1016 public void selectAllAccessibleSelection() { 1017 // To be fully implemented in a future release 1018 } 1019 1020 } // inner class AccessibleAWTComponent 1021 1022 /** 1023 * Gets the index of this object in its accessible parent. 1024 * 1025 * @return -1 if this object does not have an accessible parent; 1026 * otherwise, the index of the child in its accessible parent. 1027 */ 1028 int getAccessibleIndexInParent() { 1029 MenuContainer localParent = parent; 1030 if (!(localParent instanceof MenuComponent)) { 1031 // MenuComponents only have accessible index when inside MenuComponents 1032 return -1; 1033 } 1034 MenuComponent localParentMenu = (MenuComponent)localParent; 1035 return localParentMenu.getAccessibleChildIndex(this); 1036 } 1037 1038 /** 1039 * Gets the index of the child within this MenuComponent. 1040 * 1041 * @param child MenuComponent whose index we are interested in. 1042 * @return -1 if this object doesn't contain the child, 1043 * otherwise, index of the child. 1044 */ 1045 int getAccessibleChildIndex(MenuComponent child) { 1046 return -1; // Overridden in subclasses. 1047 } 1048 1049 /** 1050 * Gets the state of this object. 1051 * 1052 * @return an instance of <code>AccessibleStateSet</code> 1053 * containing the current state set of the object 1054 * @see AccessibleState 1055 */ 1056 AccessibleStateSet getAccessibleStateSet() { 1057 AccessibleStateSet states = new AccessibleStateSet(); 1058 return states; 1059 } 1060 1061 }