1 /*
2 * Copyright (c) 1997, 2007, 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 javax.swing;
26
27 import java.beans.*;
28 import java.util.*;
29
30 import java.awt.*;
31 import java.awt.event.*;
32
33 import java.io.Serializable;
34 import java.io.ObjectOutputStream;
35 import java.io.IOException;
36
37 import javax.swing.event.*;
38 import javax.swing.plaf.*;
39
40 import javax.accessibility.*;
41
42 /**
43 * A component that combines a button or editable field and a drop-down list.
44 * The user can select a value from the drop-down list, which appears at the
45 * user's request. If you make the combo box editable, then the combo box
46 * includes an editable field into which the user can type a value.
47 * <p>
48 * <strong>Warning:</strong> Swing is not thread safe. For more
49 * information see <a
50 * href="package-summary.html#threading">Swing's Threading
51 * Policy</a>.
52 * <p>
53 * <strong>Warning:</strong>
54 * Serialized objects of this class will not be compatible with
55 * future Swing releases. The current serialization support is
56 * appropriate for short term storage or RMI between applications running
57 * the same version of Swing. As of 1.4, support for long term storage
58 * of all JavaBeans<sup><font size="-2">TM</font></sup>
59 * has been added to the <code>java.beans</code> package.
60 * Please see {@link java.beans.XMLEncoder}.
61 *
62 * <p>
63 * See <a href="http://java.sun.com/docs/books/tutorial/uiswing/components/combobox.html">How to Use Combo Boxes</a>
64 * in <a href="http://java.sun.com/Series/Tutorial/index.html"><em>The Java Tutorial</em></a>
65 * for further information.
66 * <p>
67 * @see ComboBoxModel
68 * @see DefaultComboBoxModel
69 *
70 * @beaninfo
71 * attribute: isContainer false
72 * description: A combination of a text field and a drop-down list.
73 *
74 * @author Arnaud Weber
75 * @author Mark Davidson
76 */
77 public class JComboBox extends JComponent
78 implements ItemSelectable,ListDataListener,ActionListener, Accessible {
79 /**
80 * @see #getUIClassID
81 * @see #readObject
82 */
83 private static final String uiClassID = "ComboBoxUI";
84
85 /**
86 * This protected field is implementation specific. Do not access directly
87 * or override. Use the accessor methods instead.
88 *
89 * @see #getModel
90 * @see #setModel
91 */
92 protected ComboBoxModel dataModel;
93 /**
94 * This protected field is implementation specific. Do not access directly
95 * or override. Use the accessor methods instead.
96 *
97 * @see #getRenderer
98 * @see #setRenderer
99 */
100 protected ListCellRenderer renderer;
101 /**
102 * This protected field is implementation specific. Do not access directly
103 * or override. Use the accessor methods instead.
104 *
105 * @see #getEditor
106 * @see #setEditor
107 */
108 protected ComboBoxEditor editor;
109 /**
110 * This protected field is implementation specific. Do not access directly
111 * or override. Use the accessor methods instead.
112 *
113 * @see #getMaximumRowCount
114 * @see #setMaximumRowCount
115 */
116 protected int maximumRowCount = 8;
117
118 /**
119 * This protected field is implementation specific. Do not access directly
120 * or override. Use the accessor methods instead.
121 *
122 * @see #isEditable
123 * @see #setEditable
124 */
125 protected boolean isEditable = false;
126 /**
127 * This protected field is implementation specific. Do not access directly
128 * or override. Use the accessor methods instead.
129 *
130 * @see #setKeySelectionManager
131 * @see #getKeySelectionManager
132 */
133 protected KeySelectionManager keySelectionManager = null;
134 /**
135 * This protected field is implementation specific. Do not access directly
136 * or override. Use the accessor methods instead.
137 *
138 * @see #setActionCommand
139 * @see #getActionCommand
140 */
141 protected String actionCommand = "comboBoxChanged";
142 /**
143 * This protected field is implementation specific. Do not access directly
144 * or override. Use the accessor methods instead.
145 *
146 * @see #setLightWeightPopupEnabled
147 * @see #isLightWeightPopupEnabled
148 */
149 protected boolean lightWeightPopupEnabled = JPopupMenu.getDefaultLightWeightPopupEnabled();
150
151 /**
152 * This protected field is implementation specific. Do not access directly
153 * or override.
154 */
155 protected Object selectedItemReminder = null;
156
157 private Object prototypeDisplayValue;
158
159 // Flag to ensure that infinite loops do not occur with ActionEvents.
160 private boolean firingActionEvent = false;
161
162 // Flag to ensure the we don't get multiple ActionEvents on item selection.
163 private boolean selectingItem = false;
164
165 /**
166 * Creates a <code>JComboBox</code> that takes its items from an
167 * existing <code>ComboBoxModel</code>. Since the
168 * <code>ComboBoxModel</code> is provided, a combo box created using
169 * this constructor does not create a default combo box model and
170 * may impact how the insert, remove and add methods behave.
171 *
172 * @param aModel the <code>ComboBoxModel</code> that provides the
173 * displayed list of items
174 * @see DefaultComboBoxModel
175 */
176 public JComboBox(ComboBoxModel aModel) {
177 super();
178 setModel(aModel);
179 init();
180 }
181
182 /**
183 * Creates a <code>JComboBox</code> that contains the elements
184 * in the specified array. By default the first item in the array
185 * (and therefore the data model) becomes selected.
186 *
187 * @param items an array of objects to insert into the combo box
188 * @see DefaultComboBoxModel
189 */
190 public JComboBox(final Object items[]) {
191 super();
192 setModel(new DefaultComboBoxModel(items));
193 init();
194 }
195
196 /**
197 * Creates a <code>JComboBox</code> that contains the elements
198 * in the specified Vector. By default the first item in the vector
199 * (and therefore the data model) becomes selected.
200 *
201 * @param items an array of vectors to insert into the combo box
202 * @see DefaultComboBoxModel
203 */
204 public JComboBox(Vector<?> items) {
205 super();
206 setModel(new DefaultComboBoxModel(items));
207 init();
208 }
209
210 /**
211 * Creates a <code>JComboBox</code> with a default data model.
212 * The default data model is an empty list of objects.
213 * Use <code>addItem</code> to add items. By default the first item
214 * in the data model becomes selected.
215 *
216 * @see DefaultComboBoxModel
217 */
218 public JComboBox() {
219 super();
220 setModel(new DefaultComboBoxModel());
221 init();
222 }
223
224 private void init() {
225 installAncestorListener();
226 setUIProperty("opaque",true);
227 updateUI();
228 }
229
230 protected void installAncestorListener() {
231 addAncestorListener(new AncestorListener(){
232 public void ancestorAdded(AncestorEvent event){ hidePopup();}
233 public void ancestorRemoved(AncestorEvent event){ hidePopup();}
234 public void ancestorMoved(AncestorEvent event){
235 if (event.getSource() != JComboBox.this)
236 hidePopup();
237 }});
238 }
239
240 /**
241 * Sets the L&F object that renders this component.
242 *
243 * @param ui the <code>ComboBoxUI</code> L&F object
244 * @see UIDefaults#getUI
245 *
246 * @beaninfo
247 * bound: true
248 * hidden: true
249 * attribute: visualUpdate true
250 * description: The UI object that implements the Component's LookAndFeel.
251 */
252 public void setUI(ComboBoxUI ui) {
253 super.setUI(ui);
254 }
255
256 /**
257 * Resets the UI property to a value from the current look and feel.
258 *
259 * @see JComponent#updateUI
260 */
261 public void updateUI() {
262 setUI((ComboBoxUI)UIManager.getUI(this));
263
264 ListCellRenderer renderer = getRenderer();
265 if (renderer instanceof Component) {
266 SwingUtilities.updateComponentTreeUI((Component)renderer);
267 }
268 }
269
270
271 /**
272 * Returns the name of the L&F class that renders this component.
273 *
274 * @return the string "ComboBoxUI"
275 * @see JComponent#getUIClassID
276 * @see UIDefaults#getUI
277 */
278 public String getUIClassID() {
279 return uiClassID;
280 }
281
282
283 /**
284 * Returns the L&F object that renders this component.
285 *
286 * @return the ComboBoxUI object that renders this component
287 */
288 public ComboBoxUI getUI() {
289 return(ComboBoxUI)ui;
290 }
291
292 /**
293 * Sets the data model that the <code>JComboBox</code> uses to obtain
294 * the list of items.
295 *
296 * @param aModel the <code>ComboBoxModel</code> that provides the
297 * displayed list of items
298 *
299 * @beaninfo
300 * bound: true
301 * description: Model that the combo box uses to get data to display.
302 */
303 public void setModel(ComboBoxModel aModel) {
304 ComboBoxModel oldModel = dataModel;
305 if (oldModel != null) {
306 oldModel.removeListDataListener(this);
307 }
308 dataModel = aModel;
309 dataModel.addListDataListener(this);
310
311 // set the current selected item.
312 selectedItemReminder = dataModel.getSelectedItem();
313
314 firePropertyChange( "model", oldModel, dataModel);
315 }
316
317 /**
318 * Returns the data model currently used by the <code>JComboBox</code>.
319 *
320 * @return the <code>ComboBoxModel</code> that provides the displayed
321 * list of items
322 */
323 public ComboBoxModel getModel() {
324 return dataModel;
325 }
326
327 /*
328 * Properties
329 */
330
331 /**
332 * Sets the <code>lightWeightPopupEnabled</code> property, which
333 * provides a hint as to whether or not a lightweight
334 * <code>Component</code> should be used to contain the
335 * <code>JComboBox</code>, versus a heavyweight
336 * <code>Component</code> such as a <code>Panel</code>
337 * or a <code>Window</code>. The decision of lightweight
338 * versus heavyweight is ultimately up to the
339 * <code>JComboBox</code>. Lightweight windows are more
340 * efficient than heavyweight windows, but lightweight
341 * and heavyweight components do not mix well in a GUI.
342 * If your application mixes lightweight and heavyweight
343 * components, you should disable lightweight popups.
344 * The default value for the <code>lightWeightPopupEnabled</code>
345 * property is <code>true</code>, unless otherwise specified
346 * by the look and feel. Some look and feels always use
347 * heavyweight popups, no matter what the value of this property.
348 * <p>
349 * See the article <a href="http://java.sun.com/products/jfc/tsc/articles/mixing/index.html">Mixing Heavy and Light Components</a>
350 * on <a href="http://java.sun.com/products/jfc/tsc">
351 * <em>The Swing Connection</em></a>
352 * This method fires a property changed event.
353 *
354 * @param aFlag if <code>true</code>, lightweight popups are desired
355 *
356 * @beaninfo
357 * bound: true
358 * expert: true
359 * description: Set to <code>false</code> to require heavyweight popups.
360 */
361 public void setLightWeightPopupEnabled(boolean aFlag) {
362 boolean oldFlag = lightWeightPopupEnabled;
363 lightWeightPopupEnabled = aFlag;
364 firePropertyChange("lightWeightPopupEnabled", oldFlag, lightWeightPopupEnabled);
365 }
366
367 /**
368 * Gets the value of the <code>lightWeightPopupEnabled</code>
369 * property.
370 *
371 * @return the value of the <code>lightWeightPopupEnabled</code>
372 * property
373 * @see #setLightWeightPopupEnabled
374 */
375 public boolean isLightWeightPopupEnabled() {
376 return lightWeightPopupEnabled;
377 }
378
379 /**
380 * Determines whether the <code>JComboBox</code> field is editable.
381 * An editable <code>JComboBox</code> allows the user to type into the
382 * field or selected an item from the list to initialize the field,
383 * after which it can be edited. (The editing affects only the field,
384 * the list item remains intact.) A non editable <code>JComboBox</code>
385 * displays the selected item in the field,
386 * but the selection cannot be modified.
387 *
388 * @param aFlag a boolean value, where true indicates that the
389 * field is editable
390 *
391 * @beaninfo
392 * bound: true
393 * preferred: true
394 * description: If true, the user can type a new value in the combo box.
395 */
396 public void setEditable(boolean aFlag) {
397 boolean oldFlag = isEditable;
398 isEditable = aFlag;
399 firePropertyChange( "editable", oldFlag, isEditable );
400 }
401
402 /**
403 * Returns true if the <code>JComboBox</code> is editable.
404 * By default, a combo box is not editable.
405 *
406 * @return true if the <code>JComboBox</code> is editable, else false
407 */
408 public boolean isEditable() {
409 return isEditable;
410 }
411
412 /**
413 * Sets the maximum number of rows the <code>JComboBox</code> displays.
414 * If the number of objects in the model is greater than count,
415 * the combo box uses a scrollbar.
416 *
417 * @param count an integer specifying the maximum number of items to
418 * display in the list before using a scrollbar
419 * @beaninfo
420 * bound: true
421 * preferred: true
422 * description: The maximum number of rows the popup should have
423 */
424 public void setMaximumRowCount(int count) {
425 int oldCount = maximumRowCount;
426 maximumRowCount = count;
427 firePropertyChange( "maximumRowCount", oldCount, maximumRowCount );
428 }
429
430 /**
431 * Returns the maximum number of items the combo box can display
432 * without a scrollbar
433 *
434 * @return an integer specifying the maximum number of items that are
435 * displayed in the list before using a scrollbar
436 */
437 public int getMaximumRowCount() {
438 return maximumRowCount;
439 }
440
441 /**
442 * Sets the renderer that paints the list items and the item selected from the list in
443 * the JComboBox field. The renderer is used if the JComboBox is not
444 * editable. If it is editable, the editor is used to render and edit
445 * the selected item.
446 * <p>
447 * The default renderer displays a string or an icon.
448 * Other renderers can handle graphic images and composite items.
449 * <p>
450 * To display the selected item,
451 * <code>aRenderer.getListCellRendererComponent</code>
452 * is called, passing the list object and an index of -1.
453 *
454 * @param aRenderer the <code>ListCellRenderer</code> that
455 * displays the selected item
456 * @see #setEditor
457 * @beaninfo
458 * bound: true
459 * expert: true
460 * description: The renderer that paints the item selected in the list.
461 */
462 public void setRenderer(ListCellRenderer aRenderer) {
463 ListCellRenderer oldRenderer = renderer;
464 renderer = aRenderer;
465 firePropertyChange( "renderer", oldRenderer, renderer );
466 invalidate();
467 }
468
469 /**
470 * Returns the renderer used to display the selected item in the
471 * <code>JComboBox</code> field.
472 *
473 * @return the <code>ListCellRenderer</code> that displays
474 * the selected item.
475 */
476 public ListCellRenderer getRenderer() {
477 return renderer;
478 }
479
480 /**
481 * Sets the editor used to paint and edit the selected item in the
482 * <code>JComboBox</code> field. The editor is used only if the
483 * receiving <code>JComboBox</code> is editable. If not editable,
484 * the combo box uses the renderer to paint the selected item.
485 *
486 * @param anEditor the <code>ComboBoxEditor</code> that
487 * displays the selected item
488 * @see #setRenderer
489 * @beaninfo
490 * bound: true
491 * expert: true
492 * description: The editor that combo box uses to edit the current value
493 */
494 public void setEditor(ComboBoxEditor anEditor) {
495 ComboBoxEditor oldEditor = editor;
496
497 if ( editor != null ) {
498 editor.removeActionListener(this);
499 }
500 editor = anEditor;
501 if ( editor != null ) {
502 editor.addActionListener(this);
503 }
504 firePropertyChange( "editor", oldEditor, editor );
505 }
506
507 /**
508 * Returns the editor used to paint and edit the selected item in the
509 * <code>JComboBox</code> field.
510 *
511 * @return the <code>ComboBoxEditor</code> that displays the selected item
512 */
513 public ComboBoxEditor getEditor() {
514 return editor;
515 }
516
517 //
518 // Selection
519 //
520
521 /**
522 * Sets the selected item in the combo box display area to the object in
523 * the argument.
524 * If <code>anObject</code> is in the list, the display area shows
525 * <code>anObject</code> selected.
526 * <p>
527 * If <code>anObject</code> is <i>not</i> in the list and the combo box is
528 * uneditable, it will not change the current selection. For editable
529 * combo boxes, the selection will change to <code>anObject</code>.
530 * <p>
531 * If this constitutes a change in the selected item,
532 * <code>ItemListener</code>s added to the combo box will be notified with
533 * one or two <code>ItemEvent</code>s.
534 * If there is a current selected item, an <code>ItemEvent</code> will be
535 * fired and the state change will be <code>ItemEvent.DESELECTED</code>.
536 * If <code>anObject</code> is in the list and is not currently selected
537 * then an <code>ItemEvent</code> will be fired and the state change will
538 * be <code>ItemEvent.SELECTED</code>.
539 * <p>
540 * <code>ActionListener</code>s added to the combo box will be notified
541 * with an <code>ActionEvent</code> when this method is called.
542 *
543 * @param anObject the list object to select; use <code>null</code> to
544 clear the selection
545 * @beaninfo
546 * preferred: true
547 * description: Sets the selected item in the JComboBox.
548 */
549 public void setSelectedItem(Object anObject) {
550 Object oldSelection = selectedItemReminder;
551 Object objectToSelect = anObject;
552 if (oldSelection == null || !oldSelection.equals(anObject)) {
553
554 if (anObject != null && !isEditable()) {
555 // For non editable combo boxes, an invalid selection
556 // will be rejected.
557 boolean found = false;
558 for (int i = 0; i < dataModel.getSize(); i++) {
559 Object element = dataModel.getElementAt(i);
560 if (anObject.equals(element)) {
561 found = true;
562 objectToSelect = element;
563 break;
564 }
565 }
566 if (!found) {
567 return;
568 }
569 }
570
571 // Must toggle the state of this flag since this method
572 // call may result in ListDataEvents being fired.
573 selectingItem = true;
574 dataModel.setSelectedItem(objectToSelect);
575 selectingItem = false;
576
577 if (selectedItemReminder != dataModel.getSelectedItem()) {
578 // in case a users implementation of ComboBoxModel
579 // doesn't fire a ListDataEvent when the selection
580 // changes.
581 selectedItemChanged();
582 }
583 }
584 fireActionEvent();
585 }
586
587 /**
588 * Returns the current selected item.
589 * <p>
590 * If the combo box is editable, then this value may not have been added
591 * to the combo box with <code>addItem</code>, <code>insertItemAt</code>
592 * or the data constructors.
593 *
594 * @return the current selected Object
595 * @see #setSelectedItem
596 */
597 public Object getSelectedItem() {
598 return dataModel.getSelectedItem();
599 }
600
601 /**
602 * Selects the item at index <code>anIndex</code>.
603 *
604 * @param anIndex an integer specifying the list item to select,
605 * where 0 specifies the first item in the list and -1 indicates no selection
606 * @exception IllegalArgumentException if <code>anIndex</code> < -1 or
607 * <code>anIndex</code> is greater than or equal to size
608 * @beaninfo
609 * preferred: true
610 * description: The item at index is selected.
611 */
612 public void setSelectedIndex(int anIndex) {
613 int size = dataModel.getSize();
614
615 if ( anIndex == -1 ) {
616 setSelectedItem( null );
617 } else if ( anIndex < -1 || anIndex >= size ) {
618 throw new IllegalArgumentException("setSelectedIndex: " + anIndex + " out of bounds");
619 } else {
620 setSelectedItem(dataModel.getElementAt(anIndex));
621 }
622 }
623
624 /**
625 * Returns the first item in the list that matches the given item.
626 * The result is not always defined if the <code>JComboBox</code>
627 * allows selected items that are not in the list.
628 * Returns -1 if there is no selected item or if the user specified
629 * an item which is not in the list.
630
631 * @return an integer specifying the currently selected list item,
632 * where 0 specifies
633 * the first item in the list;
634 * or -1 if no item is selected or if
635 * the currently selected item is not in the list
636 */
637 public int getSelectedIndex() {
638 Object sObject = dataModel.getSelectedItem();
639 int i,c;
640 Object obj;
641
642 for ( i=0,c=dataModel.getSize();i<c;i++ ) {
643 obj = dataModel.getElementAt(i);
644 if ( obj != null && obj.equals(sObject) )
645 return i;
646 }
647 return -1;
648 }
649
650 /**
651 * Returns the "prototypical display" value - an Object used
652 * for the calculation of the display height and width.
653 *
654 * @return the value of the <code>prototypeDisplayValue</code> property
655 * @see #setPrototypeDisplayValue
656 * @since 1.4
657 */
658 public Object getPrototypeDisplayValue() {
659 return prototypeDisplayValue;
660 }
661
662 /**
663 * Sets the prototype display value used to calculate the size of the display
664 * for the UI portion.
665 * <p>
666 * If a prototype display value is specified, the preferred size of
667 * the combo box is calculated by configuring the renderer with the
668 * prototype display value and obtaining its preferred size. Specifying
669 * the preferred display value is often useful when the combo box will be
670 * displaying large amounts of data. If no prototype display value has
671 * been specified, the renderer must be configured for each value from
672 * the model and its preferred size obtained, which can be
673 * relatively expensive.
674 *
675 * @param prototypeDisplayValue
676 * @see #getPrototypeDisplayValue
677 * @since 1.4
678 * @beaninfo
679 * bound: true
680 * attribute: visualUpdate true
681 * description: The display prototype value, used to compute display width and height.
682 */
683 public void setPrototypeDisplayValue(Object prototypeDisplayValue) {
684 Object oldValue = this.prototypeDisplayValue;
685 this.prototypeDisplayValue = prototypeDisplayValue;
686 firePropertyChange("prototypeDisplayValue", oldValue, prototypeDisplayValue);
687 }
688
689 /**
690 * Adds an item to the item list.
691 * This method works only if the <code>JComboBox</code> uses a
692 * mutable data model.
693 * <p>
694 * <strong>Warning:</strong>
695 * Focus and keyboard navigation problems may arise if you add duplicate
696 * String objects. A workaround is to add new objects instead of String
697 * objects and make sure that the toString() method is defined.
698 * For example:
699 * <pre>
700 * comboBox.addItem(makeObj("Item 1"));
701 * comboBox.addItem(makeObj("Item 1"));
702 * ...
703 * private Object makeObj(final String item) {
704 * return new Object() { public String toString() { return item; } };
705 * }
706 * </pre>
707 *
708 * @param anObject the Object to add to the list
709 * @see MutableComboBoxModel
710 */
711 public void addItem(Object anObject) {
712 checkMutableComboBoxModel();
713 ((MutableComboBoxModel)dataModel).addElement(anObject);
714 }
715
716 /**
717 * Inserts an item into the item list at a given index.
718 * This method works only if the <code>JComboBox</code> uses a
719 * mutable data model.
720 *
721 * @param anObject the <code>Object</code> to add to the list
722 * @param index an integer specifying the position at which
723 * to add the item
724 * @see MutableComboBoxModel
725 */
726 public void insertItemAt(Object anObject, int index) {
727 checkMutableComboBoxModel();
728 ((MutableComboBoxModel)dataModel).insertElementAt(anObject,index);
729 }
730
731 /**
732 * Removes an item from the item list.
733 * This method works only if the <code>JComboBox</code> uses a
734 * mutable data model.
735 *
736 * @param anObject the object to remove from the item list
737 * @see MutableComboBoxModel
738 */
739 public void removeItem(Object anObject) {
740 checkMutableComboBoxModel();
741 ((MutableComboBoxModel)dataModel).removeElement(anObject);
742 }
743
744 /**
745 * Removes the item at <code>anIndex</code>
746 * This method works only if the <code>JComboBox</code> uses a
747 * mutable data model.
748 *
749 * @param anIndex an int specifying the index of the item to remove,
750 * where 0
751 * indicates the first item in the list
752 * @see MutableComboBoxModel
753 */
754 public void removeItemAt(int anIndex) {
755 checkMutableComboBoxModel();
756 ((MutableComboBoxModel)dataModel).removeElementAt( anIndex );
757 }
758
759 /**
760 * Removes all items from the item list.
761 */
762 public void removeAllItems() {
763 checkMutableComboBoxModel();
764 MutableComboBoxModel model = (MutableComboBoxModel)dataModel;
765 int size = model.getSize();
766
767 if ( model instanceof DefaultComboBoxModel ) {
768 ((DefaultComboBoxModel)model).removeAllElements();
769 }
770 else {
771 for ( int i = 0; i < size; ++i ) {
772 Object element = model.getElementAt( 0 );
773 model.removeElement( element );
774 }
775 }
776 selectedItemReminder = null;
777 if (isEditable()) {
778 editor.setItem(null);
779 }
780 }
781
782 /**
783 * Checks that the <code>dataModel</code> is an instance of
784 * <code>MutableComboBoxModel</code>. If not, it throws an exception.
785 * @exception RuntimeException if <code>dataModel</code> is not an
786 * instance of <code>MutableComboBoxModel</code>.
787 */
788 void checkMutableComboBoxModel() {
789 if ( !(dataModel instanceof MutableComboBoxModel) )
790 throw new RuntimeException("Cannot use this method with a non-Mutable data model.");
791 }
792
793 /**
794 * Causes the combo box to display its popup window.
795 * @see #setPopupVisible
796 */
797 public void showPopup() {
798 setPopupVisible(true);
799 }
800
801 /**
802 * Causes the combo box to close its popup window.
803 * @see #setPopupVisible
804 */
805 public void hidePopup() {
806 setPopupVisible(false);
807 }
808
809 /**
810 * Sets the visibility of the popup.
811 */
812 public void setPopupVisible(boolean v) {
813 getUI().setPopupVisible(this, v);
814 }
815
816 /**
817 * Determines the visibility of the popup.
818 *
819 * @return true if the popup is visible, otherwise returns false
820 */
821 public boolean isPopupVisible() {
822 return getUI().isPopupVisible(this);
823 }
824
825 /** Selection **/
826
827 /**
828 * Adds an <code>ItemListener</code>.
829 * <p>
830 * <code>aListener</code> will receive one or two <code>ItemEvent</code>s when
831 * the selected item changes.
832 *
833 * @param aListener the <code>ItemListener</code> that is to be notified
834 * @see #setSelectedItem
835 */
836 public void addItemListener(ItemListener aListener) {
837 listenerList.add(ItemListener.class,aListener);
838 }
839
840 /** Removes an <code>ItemListener</code>.
841 *
842 * @param aListener the <code>ItemListener</code> to remove
843 */
844 public void removeItemListener(ItemListener aListener) {
845 listenerList.remove(ItemListener.class,aListener);
846 }
847
848 /**
849 * Returns an array of all the <code>ItemListener</code>s added
850 * to this JComboBox with addItemListener().
851 *
852 * @return all of the <code>ItemListener</code>s added or an empty
853 * array if no listeners have been added
854 * @since 1.4
855 */
856 public ItemListener[] getItemListeners() {
857 return (ItemListener[])listenerList.getListeners(ItemListener.class);
858 }
859
860 /**
861 * Adds an <code>ActionListener</code>.
862 * <p>
863 * The <code>ActionListener</code> will receive an <code>ActionEvent</code>
864 * when a selection has been made. If the combo box is editable, then
865 * an <code>ActionEvent</code> will be fired when editing has stopped.
866 *
867 * @param l the <code>ActionListener</code> that is to be notified
868 * @see #setSelectedItem
869 */
870 public void addActionListener(ActionListener l) {
871 listenerList.add(ActionListener.class,l);
872 }
873
874 /** Removes an <code>ActionListener</code>.
875 *
876 * @param l the <code>ActionListener</code> to remove
877 */
878 public void removeActionListener(ActionListener l) {
879 if ((l != null) && (getAction() == l)) {
880 setAction(null);
881 } else {
882 listenerList.remove(ActionListener.class, l);
883 }
884 }
885
886 /**
887 * Returns an array of all the <code>ActionListener</code>s added
888 * to this JComboBox with addActionListener().
889 *
890 * @return all of the <code>ActionListener</code>s added or an empty
891 * array if no listeners have been added
892 * @since 1.4
893 */
894 public ActionListener[] getActionListeners() {
895 return (ActionListener[])listenerList.getListeners(
896 ActionListener.class);
897 }
898
899 /**
900 * Adds a <code>PopupMenu</code> listener which will listen to notification
901 * messages from the popup portion of the combo box.
902 * <p>
903 * For all standard look and feels shipped with Java, the popup list
904 * portion of combo box is implemented as a <code>JPopupMenu</code>.
905 * A custom look and feel may not implement it this way and will
906 * therefore not receive the notification.
907 *
908 * @param l the <code>PopupMenuListener</code> to add
909 * @since 1.4
910 */
911 public void addPopupMenuListener(PopupMenuListener l) {
912 listenerList.add(PopupMenuListener.class,l);
913 }
914
915 /**
916 * Removes a <code>PopupMenuListener</code>.
917 *
918 * @param l the <code>PopupMenuListener</code> to remove
919 * @see #addPopupMenuListener
920 * @since 1.4
921 */
922 public void removePopupMenuListener(PopupMenuListener l) {
923 listenerList.remove(PopupMenuListener.class,l);
924 }
925
926 /**
927 * Returns an array of all the <code>PopupMenuListener</code>s added
928 * to this JComboBox with addPopupMenuListener().
929 *
930 * @return all of the <code>PopupMenuListener</code>s added or an empty
931 * array if no listeners have been added
932 * @since 1.4
933 */
934 public PopupMenuListener[] getPopupMenuListeners() {
935 return (PopupMenuListener[])listenerList.getListeners(
936 PopupMenuListener.class);
937 }
938
939 /**
940 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
941 * combo box will become visible.
942 * <p>
943 * This method is public but should not be called by anything other than
944 * the UI delegate.
945 * @see #addPopupMenuListener
946 * @since 1.4
947 */
948 public void firePopupMenuWillBecomeVisible() {
949 Object[] listeners = listenerList.getListenerList();
950 PopupMenuEvent e=null;
951 for (int i = listeners.length-2; i>=0; i-=2) {
952 if (listeners[i]==PopupMenuListener.class) {
953 if (e == null)
954 e = new PopupMenuEvent(this);
955 ((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeVisible(e);
956 }
957 }
958 }
959
960 /**
961 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
962 * combo box has become invisible.
963 * <p>
964 * This method is public but should not be called by anything other than
965 * the UI delegate.
966 * @see #addPopupMenuListener
967 * @since 1.4
968 */
969 public void firePopupMenuWillBecomeInvisible() {
970 Object[] listeners = listenerList.getListenerList();
971 PopupMenuEvent e=null;
972 for (int i = listeners.length-2; i>=0; i-=2) {
973 if (listeners[i]==PopupMenuListener.class) {
974 if (e == null)
975 e = new PopupMenuEvent(this);
976 ((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeInvisible(e);
977 }
978 }
979 }
980
981 /**
982 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
983 * combo box has been canceled.
984 * <p>
985 * This method is public but should not be called by anything other than
986 * the UI delegate.
987 * @see #addPopupMenuListener
988 * @since 1.4
989 */
990 public void firePopupMenuCanceled() {
991 Object[] listeners = listenerList.getListenerList();
992 PopupMenuEvent e=null;
993 for (int i = listeners.length-2; i>=0; i-=2) {
994 if (listeners[i]==PopupMenuListener.class) {
995 if (e == null)
996 e = new PopupMenuEvent(this);
997 ((PopupMenuListener)listeners[i+1]).popupMenuCanceled(e);
998 }
999 }
1000 }
1001
1002 /**
1003 * Sets the action command that should be included in the event
1004 * sent to action listeners.
1005 *
1006 * @param aCommand a string containing the "command" that is sent
1007 * to action listeners; the same listener can then
1008 * do different things depending on the command it
1009 * receives
1010 */
1011 public void setActionCommand(String aCommand) {
1012 actionCommand = aCommand;
1013 }
1014
1015 /**
1016 * Returns the action command that is included in the event sent to
1017 * action listeners.
1018 *
1019 * @return the string containing the "command" that is sent
1020 * to action listeners.
1021 */
1022 public String getActionCommand() {
1023 return actionCommand;
1024 }
1025
1026 private Action action;
1027 private PropertyChangeListener actionPropertyChangeListener;
1028
1029 /**
1030 * Sets the <code>Action</code> for the <code>ActionEvent</code> source.
1031 * The new <code>Action</code> replaces any previously set
1032 * <code>Action</code> but does not affect <code>ActionListeners</code>
1033 * independently added with <code>addActionListener</code>.
1034 * If the <code>Action</code> is already a registered
1035 * <code>ActionListener</code> for the <code>ActionEvent</code> source,
1036 * it is not re-registered.
1037 * <p>
1038 * Setting the <code>Action</code> results in immediately changing
1039 * all the properties described in <a href="Action.html#buttonActions">
1040 * Swing Components Supporting <code>Action</code></a>.
1041 * Subsequently, the combobox's properties are automatically updated
1042 * as the <code>Action</code>'s properties change.
1043 * <p>
1044 * This method uses three other methods to set
1045 * and help track the <code>Action</code>'s property values.
1046 * It uses the <code>configurePropertiesFromAction</code> method
1047 * to immediately change the combobox's properties.
1048 * To track changes in the <code>Action</code>'s property values,
1049 * this method registers the <code>PropertyChangeListener</code>
1050 * returned by <code>createActionPropertyChangeListener</code>. The
1051 * default {@code PropertyChangeListener} invokes the
1052 * {@code actionPropertyChanged} method when a property in the
1053 * {@code Action} changes.
1054 *
1055 * @param a the <code>Action</code> for the <code>JComboBox</code>,
1056 * or <code>null</code>.
1057 * @since 1.3
1058 * @see Action
1059 * @see #getAction
1060 * @see #configurePropertiesFromAction
1061 * @see #createActionPropertyChangeListener
1062 * @see #actionPropertyChanged
1063 * @beaninfo
1064 * bound: true
1065 * attribute: visualUpdate true
1066 * description: the Action instance connected with this ActionEvent source
1067 */
1068 public void setAction(Action a) {
1069 Action oldValue = getAction();
1070 if (action==null || !action.equals(a)) {
1071 action = a;
1072 if (oldValue!=null) {
1073 removeActionListener(oldValue);
1074 oldValue.removePropertyChangeListener(actionPropertyChangeListener);
1075 actionPropertyChangeListener = null;
1076 }
1077 configurePropertiesFromAction(action);
1078 if (action!=null) {
1079 // Don't add if it is already a listener
1080 if (!isListener(ActionListener.class, action)) {
1081 addActionListener(action);
1082 }
1083 // Reverse linkage:
1084 actionPropertyChangeListener = createActionPropertyChangeListener(action);
1085 action.addPropertyChangeListener(actionPropertyChangeListener);
1086 }
1087 firePropertyChange("action", oldValue, action);
1088 }
1089 }
1090
1091 private boolean isListener(Class c, ActionListener a) {
1092 boolean isListener = false;
1093 Object[] listeners = listenerList.getListenerList();
1094 for (int i = listeners.length-2; i>=0; i-=2) {
1095 if (listeners[i]==c && listeners[i+1]==a) {
1096 isListener=true;
1097 }
1098 }
1099 return isListener;
1100 }
1101
1102 /**
1103 * Returns the currently set <code>Action</code> for this
1104 * <code>ActionEvent</code> source, or <code>null</code> if no
1105 * <code>Action</code> is set.
1106 *
1107 * @return the <code>Action</code> for this <code>ActionEvent</code>
1108 * source; or <code>null</code>
1109 * @since 1.3
1110 * @see Action
1111 * @see #setAction
1112 */
1113 public Action getAction() {
1114 return action;
1115 }
1116
1117 /**
1118 * Sets the properties on this combobox to match those in the specified
1119 * <code>Action</code>. Refer to <a href="Action.html#buttonActions">
1120 * Swing Components Supporting <code>Action</code></a> for more
1121 * details as to which properties this sets.
1122 *
1123 * @param a the <code>Action</code> from which to get the properties,
1124 * or <code>null</code>
1125 * @since 1.3
1126 * @see Action
1127 * @see #setAction
1128 */
1129 protected void configurePropertiesFromAction(Action a) {
1130 AbstractAction.setEnabledFromAction(this, a);
1131 AbstractAction.setToolTipTextFromAction(this, a);
1132 setActionCommandFromAction(a);
1133 }
1134
1135 /**
1136 * Creates and returns a <code>PropertyChangeListener</code> that is
1137 * responsible for listening for changes from the specified
1138 * <code>Action</code> and updating the appropriate properties.
1139 * <p>
1140 * <b>Warning:</b> If you subclass this do not create an anonymous
1141 * inner class. If you do the lifetime of the combobox will be tied to
1142 * that of the <code>Action</code>.
1143 *
1144 * @param a the combobox's action
1145 * @since 1.3
1146 * @see Action
1147 * @see #setAction
1148 */
1149 protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
1150 return new ComboBoxActionPropertyChangeListener(this, a);
1151 }
1152
1153 /**
1154 * Updates the combobox's state in response to property changes in
1155 * associated action. This method is invoked from the
1156 * {@code PropertyChangeListener} returned from
1157 * {@code createActionPropertyChangeListener}. Subclasses do not normally
1158 * need to invoke this. Subclasses that support additional {@code Action}
1159 * properties should override this and
1160 * {@code configurePropertiesFromAction}.
1161 * <p>
1162 * Refer to the table at <a href="Action.html#buttonActions">
1163 * Swing Components Supporting <code>Action</code></a> for a list of
1164 * the properties this method sets.
1165 *
1166 * @param action the <code>Action</code> associated with this combobox
1167 * @param propertyName the name of the property that changed
1168 * @since 1.6
1169 * @see Action
1170 * @see #configurePropertiesFromAction
1171 */
1172 protected void actionPropertyChanged(Action action, String propertyName) {
1173 if (propertyName == Action.ACTION_COMMAND_KEY) {
1174 setActionCommandFromAction(action);
1175 } else if (propertyName == "enabled") {
1176 AbstractAction.setEnabledFromAction(this, action);
1177 } else if (Action.SHORT_DESCRIPTION == propertyName) {
1178 AbstractAction.setToolTipTextFromAction(this, action);
1179 }
1180 }
1181
1182 private void setActionCommandFromAction(Action a) {
1183 setActionCommand((a != null) ?
1184 (String)a.getValue(Action.ACTION_COMMAND_KEY) :
1185 null);
1186 }
1187
1188
1189 private static class ComboBoxActionPropertyChangeListener
1190 extends ActionPropertyChangeListener<JComboBox> {
1191 ComboBoxActionPropertyChangeListener(JComboBox b, Action a) {
1192 super(b, a);
1193 }
1194 protected void actionPropertyChanged(JComboBox cb,
1195 Action action,
1196 PropertyChangeEvent e) {
1197 if (AbstractAction.shouldReconfigure(e)) {
1198 cb.configurePropertiesFromAction(action);
1199 } else {
1200 cb.actionPropertyChanged(action, e.getPropertyName());
1201 }
1202 }
1203 }
1204
1205 /**
1206 * Notifies all listeners that have registered interest for
1207 * notification on this event type.
1208 * @param e the event of interest
1209 *
1210 * @see EventListenerList
1211 */
1212 protected void fireItemStateChanged(ItemEvent e) {
1213 // Guaranteed to return a non-null array
1214 Object[] listeners = listenerList.getListenerList();
1215 // Process the listeners last to first, notifying
1216 // those that are interested in this event
1217 for ( int i = listeners.length-2; i>=0; i-=2 ) {
1218 if ( listeners[i]==ItemListener.class ) {
1219 // Lazily create the event:
1220 // if (changeEvent == null)
1221 // changeEvent = new ChangeEvent(this);
1222 ((ItemListener)listeners[i+1]).itemStateChanged(e);
1223 }
1224 }
1225 }
1226
1227 /**
1228 * Notifies all listeners that have registered interest for
1229 * notification on this event type.
1230 *
1231 * @see EventListenerList
1232 */
1233 protected void fireActionEvent() {
1234 if (!firingActionEvent) {
1235 // Set flag to ensure that an infinite loop is not created
1236 firingActionEvent = true;
1237 ActionEvent e = null;
1238 // Guaranteed to return a non-null array
1239 Object[] listeners = listenerList.getListenerList();
1240 long mostRecentEventTime = EventQueue.getMostRecentEventTime();
1241 int modifiers = 0;
1242 AWTEvent currentEvent = EventQueue.getCurrentEvent();
1243 if (currentEvent instanceof InputEvent) {
1244 modifiers = ((InputEvent)currentEvent).getModifiers();
1245 } else if (currentEvent instanceof ActionEvent) {
1246 modifiers = ((ActionEvent)currentEvent).getModifiers();
1247 }
1248 // Process the listeners last to first, notifying
1249 // those that are interested in this event
1250 for ( int i = listeners.length-2; i>=0; i-=2 ) {
1251 if ( listeners[i]==ActionListener.class ) {
1252 // Lazily create the event:
1253 if ( e == null )
1254 e = new ActionEvent(this,ActionEvent.ACTION_PERFORMED,
1255 getActionCommand(),
1256 mostRecentEventTime, modifiers);
1257 ((ActionListener)listeners[i+1]).actionPerformed(e);
1258 }
1259 }
1260 firingActionEvent = false;
1261 }
1262 }
1263
1264 /**
1265 * This protected method is implementation specific. Do not access directly
1266 * or override.
1267 */
1268 protected void selectedItemChanged() {
1269 if (selectedItemReminder != null ) {
1270 fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
1271 selectedItemReminder,
1272 ItemEvent.DESELECTED));
1273 }
1274
1275 // set the new selected item.
1276 selectedItemReminder = dataModel.getSelectedItem();
1277
1278 if (selectedItemReminder != null ) {
1279 fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
1280 selectedItemReminder,
1281 ItemEvent.SELECTED));
1282 }
1283 }
1284
1285 /**
1286 * Returns an array containing the selected item.
1287 * This method is implemented for compatibility with
1288 * <code>ItemSelectable</code>.
1289 *
1290 * @return an array of <code>Objects</code> containing one
1291 * element -- the selected item
1292 */
1293 public Object[] getSelectedObjects() {
1294 Object selectedObject = getSelectedItem();
1295 if ( selectedObject == null )
1296 return new Object[0];
1297 else {
1298 Object result[] = new Object[1];
1299 result[0] = selectedObject;
1300 return result;
1301 }
1302 }
1303
1304 /**
1305 * This method is public as an implementation side effect.
1306 * do not call or override.
1307 */
1308 public void actionPerformed(ActionEvent e) {
1309 Object newItem = getEditor().getItem();
1310 setPopupVisible(false);
1311 getModel().setSelectedItem(newItem);
1312 String oldCommand = getActionCommand();
1313 setActionCommand("comboBoxEdited");
1314 fireActionEvent();
1315 setActionCommand(oldCommand);
1316 }
1317
1318 /**
1319 * This method is public as an implementation side effect.
1320 * do not call or override.
1321 */
1322 public void contentsChanged(ListDataEvent e) {
1323 Object oldSelection = selectedItemReminder;
1324 Object newSelection = dataModel.getSelectedItem();
1325 if (oldSelection == null || !oldSelection.equals(newSelection)) {
1326 selectedItemChanged();
1327 if (!selectingItem) {
1328 fireActionEvent();
1329 }
1330 }
1331 }
1332
1333 /**
1334 * This method is public as an implementation side effect.
1335 * do not call or override.
1336 */
1337 public void intervalAdded(ListDataEvent e) {
1338 if (selectedItemReminder != dataModel.getSelectedItem()) {
1339 selectedItemChanged();
1340 }
1341 }
1342
1343 /**
1344 * This method is public as an implementation side effect.
1345 * do not call or override.
1346 */
1347 public void intervalRemoved(ListDataEvent e) {
1348 contentsChanged(e);
1349 }
1350
1351 /**
1352 * Selects the list item that corresponds to the specified keyboard
1353 * character and returns true, if there is an item corresponding
1354 * to that character. Otherwise, returns false.
1355 *
1356 * @param keyChar a char, typically this is a keyboard key
1357 * typed by the user
1358 */
1359 public boolean selectWithKeyChar(char keyChar) {
1360 int index;
1361
1362 if ( keySelectionManager == null )
1363 keySelectionManager = createDefaultKeySelectionManager();
1364
1365 index = keySelectionManager.selectionForKey(keyChar,getModel());
1366 if ( index != -1 ) {
1367 setSelectedIndex(index);
1368 return true;
1369 }
1370 else
1371 return false;
1372 }
1373
1374 /**
1375 * Enables the combo box so that items can be selected. When the
1376 * combo box is disabled, items cannot be selected and values
1377 * cannot be typed into its field (if it is editable).
1378 *
1379 * @param b a boolean value, where true enables the component and
1380 * false disables it
1381 * @beaninfo
1382 * bound: true
1383 * preferred: true
1384 * description: Whether the combo box is enabled.
1385 */
1386 public void setEnabled(boolean b) {
1387 super.setEnabled(b);
1388 firePropertyChange( "enabled", !isEnabled(), isEnabled() );
1389 }
1390
1391 /**
1392 * Initializes the editor with the specified item.
1393 *
1394 * @param anEditor the <code>ComboBoxEditor</code> that displays
1395 * the list item in the
1396 * combo box field and allows it to be edited
1397 * @param anItem the object to display and edit in the field
1398 */
1399 public void configureEditor(ComboBoxEditor anEditor, Object anItem) {
1400 anEditor.setItem(anItem);
1401 }
1402
1403 /**
1404 * Handles <code>KeyEvent</code>s, looking for the Tab key.
1405 * If the Tab key is found, the popup window is closed.
1406 *
1407 * @param e the <code>KeyEvent</code> containing the keyboard
1408 * key that was pressed
1409 */
1410 public void processKeyEvent(KeyEvent e) {
1411 if ( e.getKeyCode() == KeyEvent.VK_TAB ) {
1412 hidePopup();
1413 }
1414 super.processKeyEvent(e);
1415 }
1416
1417 /**
1418 * Sets the object that translates a keyboard character into a list
1419 * selection. Typically, the first selection with a matching first
1420 * character becomes the selected item.
1421 *
1422 * @beaninfo
1423 * expert: true
1424 * description: The objects that changes the selection when a key is pressed.
1425 */
1426 public void setKeySelectionManager(KeySelectionManager aManager) {
1427 keySelectionManager = aManager;
1428 }
1429
1430 /**
1431 * Returns the list's key-selection manager.
1432 *
1433 * @return the <code>KeySelectionManager</code> currently in use
1434 */
1435 public KeySelectionManager getKeySelectionManager() {
1436 return keySelectionManager;
1437 }
1438
1439 /* Accessing the model */
1440 /**
1441 * Returns the number of items in the list.
1442 *
1443 * @return an integer equal to the number of items in the list
1444 */
1445 public int getItemCount() {
1446 return dataModel.getSize();
1447 }
1448
1449 /**
1450 * Returns the list item at the specified index. If <code>index</code>
1451 * is out of range (less than zero or greater than or equal to size)
1452 * it will return <code>null</code>.
1453 *
1454 * @param index an integer indicating the list position, where the first
1455 * item starts at zero
1456 * @return the <code>Object</code> at that list position; or
1457 * <code>null</code> if out of range
1458 */
1459 public Object getItemAt(int index) {
1460 return dataModel.getElementAt(index);
1461 }
1462
1463 /**
1464 * Returns an instance of the default key-selection manager.
1465 *
1466 * @return the <code>KeySelectionManager</code> currently used by the list
1467 * @see #setKeySelectionManager
1468 */
1469 protected KeySelectionManager createDefaultKeySelectionManager() {
1470 return new DefaultKeySelectionManager();
1471 }
1472
1473
1474 /**
1475 * The interface that defines a <code>KeySelectionManager</code>.
1476 * To qualify as a <code>KeySelectionManager</code>,
1477 * the class needs to implement the method
1478 * that identifies the list index given a character and the
1479 * combo box data model.
1480 */
1481 public interface KeySelectionManager {
1482 /** Given <code>aKey</code> and the model, returns the row
1483 * that should become selected. Return -1 if no match was
1484 * found.
1485 *
1486 * @param aKey a char value, usually indicating a keyboard key that
1487 * was pressed
1488 * @param aModel a ComboBoxModel -- the component's data model, containing
1489 * the list of selectable items
1490 * @return an int equal to the selected row, where 0 is the
1491 * first item and -1 is none.
1492 */
1493 int selectionForKey(char aKey,ComboBoxModel aModel);
1494 }
1495
1496 class DefaultKeySelectionManager implements KeySelectionManager, Serializable {
1497 public int selectionForKey(char aKey,ComboBoxModel aModel) {
1498 int i,c;
1499 int currentSelection = -1;
1500 Object selectedItem = aModel.getSelectedItem();
1501 String v;
1502 String pattern;
1503
1504 if ( selectedItem != null ) {
1505 for ( i=0,c=aModel.getSize();i<c;i++ ) {
1506 if ( selectedItem == aModel.getElementAt(i) ) {
1507 currentSelection = i;
1508 break;
1509 }
1510 }
1511 }
1512
1513 pattern = ("" + aKey).toLowerCase();
1514 aKey = pattern.charAt(0);
1515
1516 for ( i = ++currentSelection, c = aModel.getSize() ; i < c ; i++ ) {
1517 Object elem = aModel.getElementAt(i);
1518 if (elem != null && elem.toString() != null) {
1519 v = elem.toString().toLowerCase();
1520 if ( v.length() > 0 && v.charAt(0) == aKey )
1521 return i;
1522 }
1523 }
1524
1525 for ( i = 0 ; i < currentSelection ; i ++ ) {
1526 Object elem = aModel.getElementAt(i);
1527 if (elem != null && elem.toString() != null) {
1528 v = elem.toString().toLowerCase();
1529 if ( v.length() > 0 && v.charAt(0) == aKey )
1530 return i;
1531 }
1532 }
1533 return -1;
1534 }
1535 }
1536
1537
1538 /**
1539 * See <code>readObject</code> and <code>writeObject</code> in
1540 * <code>JComponent</code> for more
1541 * information about serialization in Swing.
1542 */
1543 private void writeObject(ObjectOutputStream s) throws IOException {
1544 s.defaultWriteObject();
1545 if (getUIClassID().equals(uiClassID)) {
1546 byte count = JComponent.getWriteObjCounter(this);
1547 JComponent.setWriteObjCounter(this, --count);
1548 if (count == 0 && ui != null) {
1549 ui.installUI(this);
1550 }
1551 }
1552 }
1553
1554
1555 /**
1556 * Returns a string representation of this <code>JComboBox</code>.
1557 * This method is intended to be used only for debugging purposes,
1558 * and the content and format of the returned string may vary between
1559 * implementations. The returned string may be empty but may not
1560 * be <code>null</code>.
1561 *
1562 * @return a string representation of this <code>JComboBox</code>
1563 */
1564 protected String paramString() {
1565 String selectedItemReminderString = (selectedItemReminder != null ?
1566 selectedItemReminder.toString() :
1567 "");
1568 String isEditableString = (isEditable ? "true" : "false");
1569 String lightWeightPopupEnabledString = (lightWeightPopupEnabled ?
1570 "true" : "false");
1571
1572 return super.paramString() +
1573 ",isEditable=" + isEditableString +
1574 ",lightWeightPopupEnabled=" + lightWeightPopupEnabledString +
1575 ",maximumRowCount=" + maximumRowCount +
1576 ",selectedItemReminder=" + selectedItemReminderString;
1577 }
1578
1579
1580 ///////////////////
1581 // Accessibility support
1582 ///////////////////
1583
1584 /**
1585 * Gets the AccessibleContext associated with this JComboBox.
1586 * For combo boxes, the AccessibleContext takes the form of an
1587 * AccessibleJComboBox.
1588 * A new AccessibleJComboBox instance is created if necessary.
1589 *
1590 * @return an AccessibleJComboBox that serves as the
1591 * AccessibleContext of this JComboBox
1592 */
1593 public AccessibleContext getAccessibleContext() {
1594 if ( accessibleContext == null ) {
1595 accessibleContext = new AccessibleJComboBox();
1596 }
1597 return accessibleContext;
1598 }
1599
1600 /**
1601 * This class implements accessibility support for the
1602 * <code>JComboBox</code> class. It provides an implementation of the
1603 * Java Accessibility API appropriate to Combo Box user-interface elements.
1604 * <p>
1605 * <strong>Warning:</strong>
1606 * Serialized objects of this class will not be compatible with
1607 * future Swing releases. The current serialization support is
1608 * appropriate for short term storage or RMI between applications running
1609 * the same version of Swing. As of 1.4, support for long term storage
1610 * of all JavaBeans<sup><font size="-2">TM</font></sup>
1611 * has been added to the <code>java.beans</code> package.
1612 * Please see {@link java.beans.XMLEncoder}.
1613 */
1614 protected class AccessibleJComboBox extends AccessibleJComponent
1615 implements AccessibleAction, AccessibleSelection {
1616
1617
1618 private JList popupList; // combo box popup list
1619 private Accessible previousSelectedAccessible = null;
1620
1621 /**
1622 * Returns an AccessibleJComboBox instance
1623 * @since 1.4
1624 */
1625 public AccessibleJComboBox() {
1626 // set the combo box editor's accessible name and description
1627 JComboBox.this.addPropertyChangeListener(new AccessibleJComboBoxPropertyChangeListener());
1628 setEditorNameAndDescription();
1629
1630 // Get the popup list
1631 Accessible a = getUI().getAccessibleChild(JComboBox.this, 0);
1632 if (a instanceof javax.swing.plaf.basic.ComboPopup) {
1633 // Listen for changes to the popup menu selection.
1634 popupList = ((javax.swing.plaf.basic.ComboPopup)a).getList();
1635 popupList.addListSelectionListener(
1636 new AccessibleJComboBoxListSelectionListener());
1637 }
1638 // Listen for popup menu show/hide events
1639 JComboBox.this.addPopupMenuListener(
1640 new AccessibleJComboBoxPopupMenuListener());
1641 }
1642
1643 /*
1644 * JComboBox PropertyChangeListener
1645 */
1646 private class AccessibleJComboBoxPropertyChangeListener
1647 implements PropertyChangeListener {
1648
1649 public void propertyChange(PropertyChangeEvent e) {
1650 if (e.getPropertyName() == "editor") {
1651 // set the combo box editor's accessible name
1652 // and description
1653 setEditorNameAndDescription();
1654 }
1655 }
1656 }
1657
1658 /*
1659 * Sets the combo box editor's accessible name and descripton
1660 */
1661 private void setEditorNameAndDescription() {
1662 ComboBoxEditor editor = JComboBox.this.getEditor();
1663 if (editor != null) {
1664 Component comp = editor.getEditorComponent();
1665 if (comp instanceof Accessible) {
1666 AccessibleContext ac = ((Accessible)comp).getAccessibleContext();
1667 if (ac != null) { // may be null
1668 ac.setAccessibleName(getAccessibleName());
1669 ac.setAccessibleDescription(getAccessibleDescription());
1670 }
1671 }
1672 }
1673 }
1674
1675 /*
1676 * Listener for combo box popup menu
1677 * TIGER - 4669379 4894434
1678 */
1679 private class AccessibleJComboBoxPopupMenuListener
1680 implements PopupMenuListener {
1681
1682 /**
1683 * This method is called before the popup menu becomes visible
1684 */
1685 public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
1686 // save the initial selection
1687 if (popupList == null) {
1688 return;
1689 }
1690 int selectedIndex = popupList.getSelectedIndex();
1691 if (selectedIndex < 0) {
1692 return;
1693 }
1694 previousSelectedAccessible =
1695 popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
1696 }
1697
1698 /**
1699 * This method is called before the popup menu becomes invisible
1700 * Note that a JPopupMenu can become invisible any time
1701 */
1702 public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
1703 // ignore
1704 }
1705
1706 /**
1707 * This method is called when the popup menu is canceled
1708 */
1709 public void popupMenuCanceled(PopupMenuEvent e) {
1710 // ignore
1711 }
1712 }
1713
1714 /*
1715 * Handles changes to the popup list selection.
1716 * TIGER - 4669379 4894434 4933143
1717 */
1718 private class AccessibleJComboBoxListSelectionListener
1719 implements ListSelectionListener {
1720
1721 public void valueChanged(ListSelectionEvent e) {
1722 if (popupList == null) {
1723 return;
1724 }
1725
1726 // Get the selected popup list item.
1727 int selectedIndex = popupList.getSelectedIndex();
1728 if (selectedIndex < 0) {
1729 return;
1730 }
1731 Accessible selectedAccessible =
1732 popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
1733 if (selectedAccessible == null) {
1734 return;
1735 }
1736
1737 // Fire a FOCUSED lost PropertyChangeEvent for the
1738 // previously selected list item.
1739 PropertyChangeEvent pce = null;
1740
1741 if (previousSelectedAccessible != null) {
1742 pce = new PropertyChangeEvent(previousSelectedAccessible,
1743 AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1744 AccessibleState.FOCUSED, null);
1745 firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1746 null, pce);
1747 }
1748 // Fire a FOCUSED gained PropertyChangeEvent for the
1749 // currently selected list item.
1750 pce = new PropertyChangeEvent(selectedAccessible,
1751 AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1752 null, AccessibleState.FOCUSED);
1753 firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1754 null, pce);
1755
1756 // Fire the ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY event
1757 // for the combo box.
1758 firePropertyChange(AccessibleContext.ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY,
1759 previousSelectedAccessible, selectedAccessible);
1760
1761 // Save the previous selection.
1762 previousSelectedAccessible = selectedAccessible;
1763 }
1764 }
1765
1766
1767 /**
1768 * Returns the number of accessible children in the object. If all
1769 * of the children of this object implement Accessible, than this
1770 * method should return the number of children of this object.
1771 *
1772 * @return the number of accessible children in the object.
1773 */
1774 public int getAccessibleChildrenCount() {
1775 // Always delegate to the UI if it exists
1776 if (ui != null) {
1777 return ui.getAccessibleChildrenCount(JComboBox.this);
1778 } else {
1779 return super.getAccessibleChildrenCount();
1780 }
1781 }
1782
1783 /**
1784 * Returns the nth Accessible child of the object.
1785 * The child at index zero represents the popup.
1786 * If the combo box is editable, the child at index one
1787 * represents the editor.
1788 *
1789 * @param i zero-based index of child
1790 * @return the nth Accessible child of the object
1791 */
1792 public Accessible getAccessibleChild(int i) {
1793 // Always delegate to the UI if it exists
1794 if (ui != null) {
1795 return ui.getAccessibleChild(JComboBox.this, i);
1796 } else {
1797 return super.getAccessibleChild(i);
1798 }
1799 }
1800
1801 /**
1802 * Get the role of this object.
1803 *
1804 * @return an instance of AccessibleRole describing the role of the
1805 * object
1806 * @see AccessibleRole
1807 */
1808 public AccessibleRole getAccessibleRole() {
1809 return AccessibleRole.COMBO_BOX;
1810 }
1811
1812 /**
1813 * Gets the state set of this object. The AccessibleStateSet of
1814 * an object is composed of a set of unique AccessibleStates.
1815 * A change in the AccessibleStateSet of an object will cause a
1816 * PropertyChangeEvent to be fired for the ACCESSIBLE_STATE_PROPERTY
1817 * property.
1818 *
1819 * @return an instance of AccessibleStateSet containing the
1820 * current state set of the object
1821 * @see AccessibleStateSet
1822 * @see AccessibleState
1823 * @see #addPropertyChangeListener
1824 *
1825 */
1826 public AccessibleStateSet getAccessibleStateSet() {
1827 // TIGER - 4489748
1828 AccessibleStateSet ass = super.getAccessibleStateSet();
1829 if (ass == null) {
1830 ass = new AccessibleStateSet();
1831 }
1832 if (JComboBox.this.isPopupVisible()) {
1833 ass.add(AccessibleState.EXPANDED);
1834 } else {
1835 ass.add(AccessibleState.COLLAPSED);
1836 }
1837 return ass;
1838 }
1839
1840 /**
1841 * Get the AccessibleAction associated with this object. In the
1842 * implementation of the Java Accessibility API for this class,
1843 * return this object, which is responsible for implementing the
1844 * AccessibleAction interface on behalf of itself.
1845 *
1846 * @return this object
1847 */
1848 public AccessibleAction getAccessibleAction() {
1849 return this;
1850 }
1851
1852 /**
1853 * Return a description of the specified action of the object.
1854 *
1855 * @param i zero-based index of the actions
1856 */
1857 public String getAccessibleActionDescription(int i) {
1858 if (i == 0) {
1859 return UIManager.getString("ComboBox.togglePopupText");
1860 }
1861 else {
1862 return null;
1863 }
1864 }
1865
1866 /**
1867 * Returns the number of Actions available in this object. The
1868 * default behavior of a combo box is to have one action.
1869 *
1870 * @return 1, the number of Actions in this object
1871 */
1872 public int getAccessibleActionCount() {
1873 return 1;
1874 }
1875
1876 /**
1877 * Perform the specified Action on the object
1878 *
1879 * @param i zero-based index of actions
1880 * @return true if the the action was performed; else false.
1881 */
1882 public boolean doAccessibleAction(int i) {
1883 if (i == 0) {
1884 setPopupVisible(!isPopupVisible());
1885 return true;
1886 }
1887 else {
1888 return false;
1889 }
1890 }
1891
1892
1893 /**
1894 * Get the AccessibleSelection associated with this object. In the
1895 * implementation of the Java Accessibility API for this class,
1896 * return this object, which is responsible for implementing the
1897 * AccessibleSelection interface on behalf of itself.
1898 *
1899 * @return this object
1900 */
1901 public AccessibleSelection getAccessibleSelection() {
1902 return this;
1903 }
1904
1905 /**
1906 * Returns the number of Accessible children currently selected.
1907 * If no children are selected, the return value will be 0.
1908 *
1909 * @return the number of items currently selected.
1910 * @since 1.3
1911 */
1912 public int getAccessibleSelectionCount() {
1913 Object o = JComboBox.this.getSelectedItem();
1914 if (o != null) {
1915 return 1;
1916 } else {
1917 return 0;
1918 }
1919 }
1920
1921 /**
1922 * Returns an Accessible representing the specified selected child
1923 * in the popup. If there isn't a selection, or there are
1924 * fewer children selected than the integer passed in, the return
1925 * value will be null.
1926 * <p>Note that the index represents the i-th selected child, which
1927 * is different from the i-th child.
1928 *
1929 * @param i the zero-based index of selected children
1930 * @return the i-th selected child
1931 * @see #getAccessibleSelectionCount
1932 * @since 1.3
1933 */
1934 public Accessible getAccessibleSelection(int i) {
1935 // Get the popup
1936 Accessible a =
1937 JComboBox.this.getUI().getAccessibleChild(JComboBox.this, 0);
1938 if (a != null &&
1939 a instanceof javax.swing.plaf.basic.ComboPopup) {
1940
1941 // get the popup list
1942 JList list = ((javax.swing.plaf.basic.ComboPopup)a).getList();
1943
1944 // return the i-th selection in the popup list
1945 AccessibleContext ac = list.getAccessibleContext();
1946 if (ac != null) {
1947 AccessibleSelection as = ac.getAccessibleSelection();
1948 if (as != null) {
1949 return as.getAccessibleSelection(i);
1950 }
1951 }
1952 }
1953 return null;
1954 }
1955
1956 /**
1957 * Determines if the current child of this object is selected.
1958 *
1959 * @return true if the current child of this object is selected;
1960 * else false
1961 * @param i the zero-based index of the child in this Accessible
1962 * object.
1963 * @see AccessibleContext#getAccessibleChild
1964 * @since 1.3
1965 */
1966 public boolean isAccessibleChildSelected(int i) {
1967 return JComboBox.this.getSelectedIndex() == i;
1968 }
1969
1970 /**
1971 * Adds the specified Accessible child of the object to the object's
1972 * selection. If the object supports multiple selections,
1973 * the specified child is added to any existing selection, otherwise
1974 * it replaces any existing selection in the object. If the
1975 * specified child is already selected, this method has no effect.
1976 *
1977 * @param i the zero-based index of the child
1978 * @see AccessibleContext#getAccessibleChild
1979 * @since 1.3
1980 */
1981 public void addAccessibleSelection(int i) {
1982 // TIGER - 4856195
1983 clearAccessibleSelection();
1984 JComboBox.this.setSelectedIndex(i);
1985 }
1986
1987 /**
1988 * Removes the specified child of the object from the object's
1989 * selection. If the specified item isn't currently selected, this
1990 * method has no effect.
1991 *
1992 * @param i the zero-based index of the child
1993 * @see AccessibleContext#getAccessibleChild
1994 * @since 1.3
1995 */
1996 public void removeAccessibleSelection(int i) {
1997 if (JComboBox.this.getSelectedIndex() == i) {
1998 clearAccessibleSelection();
1999 }
2000 }
2001
2002 /**
2003 * Clears the selection in the object, so that no children in the
2004 * object are selected.
2005 * @since 1.3
2006 */
2007 public void clearAccessibleSelection() {
2008 JComboBox.this.setSelectedIndex(-1);
2009 }
2010
2011 /**
2012 * Causes every child of the object to be selected
2013 * if the object supports multiple selections.
2014 * @since 1.3
2015 */
2016 public void selectAllAccessibleSelection() {
2017 // do nothing since multiple selection is not supported
2018 }
2019
2020 // public Accessible getAccessibleAt(Point p) {
2021 // Accessible a = getAccessibleChild(1);
2022 // if ( a != null ) {
2023 // return a; // the editor
2024 // }
2025 // else {
2026 // return getAccessibleChild(0); // the list
2027 // }
2028 // }
2029 private EditorAccessibleContext editorAccessibleContext = null;
2030
2031 private class AccessibleEditor implements Accessible {
2032 public AccessibleContext getAccessibleContext() {
2033 if (editorAccessibleContext == null) {
2034 Component c = JComboBox.this.getEditor().getEditorComponent();
2035 if (c instanceof Accessible) {
2036 editorAccessibleContext =
2037 new EditorAccessibleContext((Accessible)c);
2038 }
2039 }
2040 return editorAccessibleContext;
2041 }
2042 }
2043
2044 /*
2045 * Wrapper class for the AccessibleContext implemented by the
2046 * combo box editor. Delegates all method calls except
2047 * getAccessibleIndexInParent to the editor. The
2048 * getAccessibleIndexInParent method returns the selected
2049 * index in the combo box.
2050 */
2051 private class EditorAccessibleContext extends AccessibleContext {
2052
2053 private AccessibleContext ac;
2054
2055 private EditorAccessibleContext() {
2056 }
2057
2058 /*
2059 * @param a the AccessibleContext implemented by the
2060 * combo box editor
2061 */
2062 EditorAccessibleContext(Accessible a) {
2063 this.ac = a.getAccessibleContext();
2064 }
2065
2066 /**
2067 * Gets the accessibleName property of this object. The accessibleName
2068 * property of an object is a localized String that designates the purpose
2069 * of the object. For example, the accessibleName property of a label
2070 * or button might be the text of the label or button itself. In the
2071 * case of an object that doesn't display its name, the accessibleName
2072 * should still be set. For example, in the case of a text field used
2073 * to enter the name of a city, the accessibleName for the en_US locale
2074 * could be 'city.'
2075 *
2076 * @return the localized name of the object; null if this
2077 * object does not have a name
2078 *
2079 * @see #setAccessibleName
2080 */
2081 public String getAccessibleName() {
2082 return ac.getAccessibleName();
2083 }
2084
2085 /**
2086 * Sets the localized accessible name of this object. Changing the
2087 * name will cause a PropertyChangeEvent to be fired for the
2088 * ACCESSIBLE_NAME_PROPERTY property.
2089 *
2090 * @param s the new localized name of the object.
2091 *
2092 * @see #getAccessibleName
2093 * @see #addPropertyChangeListener
2094 *
2095 * @beaninfo
2096 * preferred: true
2097 * description: Sets the accessible name for the component.
2098 */
2099 public void setAccessibleName(String s) {
2100 ac.setAccessibleName(s);
2101 }
2102
2103 /**
2104 * Gets the accessibleDescription property of this object. The
2105 * accessibleDescription property of this object is a short localized
2106 * phrase describing the purpose of the object. For example, in the
2107 * case of a 'Cancel' button, the accessibleDescription could be
2108 * 'Ignore changes and close dialog box.'
2109 *
2110 * @return the localized description of the object; null if
2111 * this object does not have a description
2112 *
2113 * @see #setAccessibleDescription
2114 */
2115 public String getAccessibleDescription() {
2116 return ac.getAccessibleDescription();
2117 }
2118
2119 /**
2120 * Sets the accessible description of this object. Changing the
2121 * name will cause a PropertyChangeEvent to be fired for the
2122 * ACCESSIBLE_DESCRIPTION_PROPERTY property.
2123 *
2124 * @param s the new localized description of the object
2125 *
2126 * @see #setAccessibleName
2127 * @see #addPropertyChangeListener
2128 *
2129 * @beaninfo
2130 * preferred: true
2131 * description: Sets the accessible description for the component.
2132 */
2133 public void setAccessibleDescription(String s) {
2134 ac.setAccessibleDescription(s);
2135 }
2136
2137 /**
2138 * Gets the role of this object. The role of the object is the generic
2139 * purpose or use of the class of this object. For example, the role
2140 * of a push button is AccessibleRole.PUSH_BUTTON. The roles in
2141 * AccessibleRole are provided so component developers can pick from
2142 * a set of predefined roles. This enables assistive technologies to
2143 * provide a consistent interface to various tweaked subclasses of
2144 * components (e.g., use AccessibleRole.PUSH_BUTTON for all components
2145 * that act like a push button) as well as distinguish between sublasses
2146 * that behave differently (e.g., AccessibleRole.CHECK_BOX for check boxes
2147 * and AccessibleRole.RADIO_BUTTON for radio buttons).
2148 * <p>Note that the AccessibleRole class is also extensible, so
2149 * custom component developers can define their own AccessibleRole's
2150 * if the set of predefined roles is inadequate.
2151 *
2152 * @return an instance of AccessibleRole describing the role of the object
2153 * @see AccessibleRole
2154 */
2155 public AccessibleRole getAccessibleRole() {
2156 return ac.getAccessibleRole();
2157 }
2158
2159 /**
2160 * Gets the state set of this object. The AccessibleStateSet of an object
2161 * is composed of a set of unique AccessibleStates. A change in the
2162 * AccessibleStateSet of an object will cause a PropertyChangeEvent to
2163 * be fired for the ACCESSIBLE_STATE_PROPERTY property.
2164 *
2165 * @return an instance of AccessibleStateSet containing the
2166 * current state set of the object
2167 * @see AccessibleStateSet
2168 * @see AccessibleState
2169 * @see #addPropertyChangeListener
2170 */
2171 public AccessibleStateSet getAccessibleStateSet() {
2172 return ac.getAccessibleStateSet();
2173 }
2174
2175 /**
2176 * Gets the Accessible parent of this object.
2177 *
2178 * @return the Accessible parent of this object; null if this
2179 * object does not have an Accessible parent
2180 */
2181 public Accessible getAccessibleParent() {
2182 return ac.getAccessibleParent();
2183 }
2184
2185 /**
2186 * Sets the Accessible parent of this object. This is meant to be used
2187 * only in the situations where the actual component's parent should
2188 * not be treated as the component's accessible parent and is a method
2189 * that should only be called by the parent of the accessible child.
2190 *
2191 * @param a - Accessible to be set as the parent
2192 */
2193 public void setAccessibleParent(Accessible a) {
2194 ac.setAccessibleParent(a);
2195 }
2196
2197 /**
2198 * Gets the 0-based index of this object in its accessible parent.
2199 *
2200 * @return the 0-based index of this object in its parent; -1 if this
2201 * object does not have an accessible parent.
2202 *
2203 * @see #getAccessibleParent
2204 * @see #getAccessibleChildrenCount
2205 * @see #getAccessibleChild
2206 */
2207 public int getAccessibleIndexInParent() {
2208 return JComboBox.this.getSelectedIndex();
2209 }
2210
2211 /**
2212 * Returns the number of accessible children of the object.
2213 *
2214 * @return the number of accessible children of the object.
2215 */
2216 public int getAccessibleChildrenCount() {
2217 return ac.getAccessibleChildrenCount();
2218 }
2219
2220 /**
2221 * Returns the specified Accessible child of the object. The Accessible
2222 * children of an Accessible object are zero-based, so the first child
2223 * of an Accessible child is at index 0, the second child is at index 1,
2224 * and so on.
2225 *
2226 * @param i zero-based index of child
2227 * @return the Accessible child of the object
2228 * @see #getAccessibleChildrenCount
2229 */
2230 public Accessible getAccessibleChild(int i) {
2231 return ac.getAccessibleChild(i);
2232 }
2233
2234 /**
2235 * Gets the locale of the component. If the component does not have a
2236 * locale, then the locale of its parent is returned.
2237 *
2238 * @return this component's locale. If this component does not have
2239 * a locale, the locale of its parent is returned.
2240 *
2241 * @exception IllegalComponentStateException
2242 * If the Component does not have its own locale and has not yet been
2243 * added to a containment hierarchy such that the locale can be
2244 * determined from the containing parent.
2245 */
2246 public Locale getLocale() throws IllegalComponentStateException {
2247 return ac.getLocale();
2248 }
2249
2250 /**
2251 * Adds a PropertyChangeListener to the listener list.
2252 * The listener is registered for all Accessible properties and will
2253 * be called when those properties change.
2254 *
2255 * @see #ACCESSIBLE_NAME_PROPERTY
2256 * @see #ACCESSIBLE_DESCRIPTION_PROPERTY
2257 * @see #ACCESSIBLE_STATE_PROPERTY
2258 * @see #ACCESSIBLE_VALUE_PROPERTY
2259 * @see #ACCESSIBLE_SELECTION_PROPERTY
2260 * @see #ACCESSIBLE_TEXT_PROPERTY
2261 * @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
2262 *
2263 * @param listener The PropertyChangeListener to be added
2264 */
2265 public void addPropertyChangeListener(PropertyChangeListener listener) {
2266 ac.addPropertyChangeListener(listener);
2267 }
2268
2269 /**
2270 * Removes a PropertyChangeListener from the listener list.
2271 * This removes a PropertyChangeListener that was registered
2272 * for all properties.
2273 *
2274 * @param listener The PropertyChangeListener to be removed
2275 */
2276 public void removePropertyChangeListener(PropertyChangeListener listener) {
2277 ac.removePropertyChangeListener(listener);
2278 }
2279
2280 /**
2281 * Gets the AccessibleAction associated with this object that supports
2282 * one or more actions.
2283 *
2284 * @return AccessibleAction if supported by object; else return null
2285 * @see AccessibleAction
2286 */
2287 public AccessibleAction getAccessibleAction() {
2288 return ac.getAccessibleAction();
2289 }
2290
2291 /**
2292 * Gets the AccessibleComponent associated with this object that has a
2293 * graphical representation.
2294 *
2295 * @return AccessibleComponent if supported by object; else return null
2296 * @see AccessibleComponent
2297 */
2298 public AccessibleComponent getAccessibleComponent() {
2299 return ac.getAccessibleComponent();
2300 }
2301
2302 /**
2303 * Gets the AccessibleSelection associated with this object which allows its
2304 * Accessible children to be selected.
2305 *
2306 * @return AccessibleSelection if supported by object; else return null
2307 * @see AccessibleSelection
2308 */
2309 public AccessibleSelection getAccessibleSelection() {
2310 return ac.getAccessibleSelection();
2311 }
2312
2313 /**
2314 * Gets the AccessibleText associated with this object presenting
2315 * text on the display.
2316 *
2317 * @return AccessibleText if supported by object; else return null
2318 * @see AccessibleText
2319 */
2320 public AccessibleText getAccessibleText() {
2321 return ac.getAccessibleText();
2322 }
2323
2324 /**
2325 * Gets the AccessibleEditableText associated with this object
2326 * presenting editable text on the display.
2327 *
2328 * @return AccessibleEditableText if supported by object; else return null
2329 * @see AccessibleEditableText
2330 */
2331 public AccessibleEditableText getAccessibleEditableText() {
2332 return ac.getAccessibleEditableText();
2333 }
2334
2335 /**
2336 * Gets the AccessibleValue associated with this object that supports a
2337 * Numerical value.
2338 *
2339 * @return AccessibleValue if supported by object; else return null
2340 * @see AccessibleValue
2341 */
2342 public AccessibleValue getAccessibleValue() {
2343 return ac.getAccessibleValue();
2344 }
2345
2346 /**
2347 * Gets the AccessibleIcons associated with an object that has
2348 * one or more associated icons
2349 *
2350 * @return an array of AccessibleIcon if supported by object;
2351 * otherwise return null
2352 * @see AccessibleIcon
2353 */
2354 public AccessibleIcon [] getAccessibleIcon() {
2355 return ac.getAccessibleIcon();
2356 }
2357
2358 /**
2359 * Gets the AccessibleRelationSet associated with an object
2360 *
2361 * @return an AccessibleRelationSet if supported by object;
2362 * otherwise return null
2363 * @see AccessibleRelationSet
2364 */
2365 public AccessibleRelationSet getAccessibleRelationSet() {
2366 return ac.getAccessibleRelationSet();
2367 }
2368
2369 /**
2370 * Gets the AccessibleTable associated with an object
2371 *
2372 * @return an AccessibleTable if supported by object;
2373 * otherwise return null
2374 * @see AccessibleTable
2375 */
2376 public AccessibleTable getAccessibleTable() {
2377 return ac.getAccessibleTable();
2378 }
2379
2380 /**
2381 * Support for reporting bound property changes. If oldValue and
2382 * newValue are not equal and the PropertyChangeEvent listener list
2383 * is not empty, then fire a PropertyChange event to each listener.
2384 * In general, this is for use by the Accessible objects themselves
2385 * and should not be called by an application program.
2386 * @param propertyName The programmatic name of the property that
2387 * was changed.
2388 * @param oldValue The old value of the property.
2389 * @param newValue The new value of the property.
2390 * @see java.beans.PropertyChangeSupport
2391 * @see #addPropertyChangeListener
2392 * @see #removePropertyChangeListener
2393 * @see #ACCESSIBLE_NAME_PROPERTY
2394 * @see #ACCESSIBLE_DESCRIPTION_PROPERTY
2395 * @see #ACCESSIBLE_STATE_PROPERTY
2396 * @see #ACCESSIBLE_VALUE_PROPERTY
2397 * @see #ACCESSIBLE_SELECTION_PROPERTY
2398 * @see #ACCESSIBLE_TEXT_PROPERTY
2399 * @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
2400 */
2401 public void firePropertyChange(String propertyName,
2402 Object oldValue,
2403 Object newValue) {
2404 ac.firePropertyChange(propertyName, oldValue, newValue);
2405 }
2406 }
2407
2408 } // innerclass AccessibleJComboBox
2409 }