1 /*
2 * Copyright (c) 1997, 2008, 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.PropertyChangeEvent;
28 import java.beans.PropertyChangeListener;
29 import java.beans.Transient;
30 import java.util.*;
31
32 import java.awt.*;
33 import java.awt.event.*;
34
35 import java.io.Serializable;
36 import java.io.ObjectOutputStream;
37 import java.io.IOException;
38
39 import javax.swing.event.*;
40 import javax.swing.plaf.*;
41
42 import javax.accessibility.*;
43
44 /**
45 * A component that combines a button or editable field and a drop-down list.
46 * The user can select a value from the drop-down list, which appears at the
47 * user's request. If you make the combo box editable, then the combo box
48 * includes an editable field into which the user can type a value.
49 * <p>
50 * <strong>Warning:</strong> Swing is not thread safe. For more
51 * information see <a
52 * href="package-summary.html#threading">Swing's Threading
53 * Policy</a>.
54 * <p>
55 * <strong>Warning:</strong>
56 * Serialized objects of this class will not be compatible with
57 * future Swing releases. The current serialization support is
58 * appropriate for short term storage or RMI between applications running
59 * the same version of Swing. As of 1.4, support for long term storage
60 * of all JavaBeans<sup><font size="-2">TM</font></sup>
61 * has been added to the <code>java.beans</code> package.
62 * Please see {@link java.beans.XMLEncoder}.
63 *
64 * <p>
65 * See <a href="http://docs.oracle.com/javase/tutorial/uiswing/components/combobox.html">How to Use Combo Boxes</a>
66 * in <a href="http://docs.oracle.com/javase/tutorial/"><em>The Java Tutorial</em></a>
67 * for further information.
68 * <p>
69 * @see ComboBoxModel
70 * @see DefaultComboBoxModel
71 *
72 * @param <E> the type of the elements of this combo box
73 *
74 * @beaninfo
75 * attribute: isContainer false
76 * description: A combination of a text field and a drop-down list.
77 *
78 * @author Arnaud Weber
79 * @author Mark Davidson
80 */
81 public class JComboBox<E> extends JComponent
82 implements ItemSelectable,ListDataListener,ActionListener, Accessible {
83 /**
84 * @see #getUIClassID
85 * @see #readObject
86 */
87 private static final String uiClassID = "ComboBoxUI";
88
89 /**
90 * This protected field is implementation specific. Do not access directly
91 * or override. Use the accessor methods instead.
92 *
93 * @see #getModel
94 * @see #setModel
95 */
96 protected ComboBoxModel<E> dataModel;
97 /**
98 * This protected field is implementation specific. Do not access directly
99 * or override. Use the accessor methods instead.
100 *
101 * @see #getRenderer
102 * @see #setRenderer
103 */
104 protected ListCellRenderer<? super E> renderer;
105 /**
106 * This protected field is implementation specific. Do not access directly
107 * or override. Use the accessor methods instead.
108 *
109 * @see #getEditor
110 * @see #setEditor
111 */
112 protected ComboBoxEditor editor;
113 /**
114 * This protected field is implementation specific. Do not access directly
115 * or override. Use the accessor methods instead.
116 *
117 * @see #getMaximumRowCount
118 * @see #setMaximumRowCount
119 */
120 protected int maximumRowCount = 8;
121
122 /**
123 * This protected field is implementation specific. Do not access directly
124 * or override. Use the accessor methods instead.
125 *
126 * @see #isEditable
127 * @see #setEditable
128 */
129 protected boolean isEditable = false;
130 /**
131 * This protected field is implementation specific. Do not access directly
132 * or override. Use the accessor methods instead.
133 *
134 * @see #setKeySelectionManager
135 * @see #getKeySelectionManager
136 */
137 protected KeySelectionManager keySelectionManager = null;
138 /**
139 * This protected field is implementation specific. Do not access directly
140 * or override. Use the accessor methods instead.
141 *
142 * @see #setActionCommand
143 * @see #getActionCommand
144 */
145 protected String actionCommand = "comboBoxChanged";
146 /**
147 * This protected field is implementation specific. Do not access directly
148 * or override. Use the accessor methods instead.
149 *
150 * @see #setLightWeightPopupEnabled
151 * @see #isLightWeightPopupEnabled
152 */
153 protected boolean lightWeightPopupEnabled = JPopupMenu.getDefaultLightWeightPopupEnabled();
154
155 /**
156 * This protected field is implementation specific. Do not access directly
157 * or override.
158 */
159 protected Object selectedItemReminder = null;
160
161 private E prototypeDisplayValue;
162
163 // Flag to ensure that infinite loops do not occur with ActionEvents.
164 private boolean firingActionEvent = false;
165
166 // Flag to ensure the we don't get multiple ActionEvents on item selection.
167 private boolean selectingItem = false;
168
169 /**
170 * Creates a <code>JComboBox</code> that takes its items from an
171 * existing <code>ComboBoxModel</code>. Since the
172 * <code>ComboBoxModel</code> is provided, a combo box created using
173 * this constructor does not create a default combo box model and
174 * may impact how the insert, remove and add methods behave.
175 *
176 * @param aModel the <code>ComboBoxModel</code> that provides the
177 * displayed list of items
178 * @see DefaultComboBoxModel
179 */
180 public JComboBox(ComboBoxModel<E> aModel) {
181 super();
182 setModel(aModel);
183 init();
184 }
185
186 /**
187 * Creates a <code>JComboBox</code> that contains the elements
188 * in the specified array. By default the first item in the array
189 * (and therefore the data model) becomes selected.
190 *
191 * @param items an array of objects to insert into the combo box
192 * @see DefaultComboBoxModel
193 */
194 public JComboBox(E[] items) {
195 super();
196 setModel(new DefaultComboBoxModel<E>(items));
197 init();
198 }
199
200 /**
201 * Creates a <code>JComboBox</code> that contains the elements
202 * in the specified Vector. By default the first item in the vector
203 * (and therefore the data model) becomes selected.
204 *
205 * @param items an array of vectors to insert into the combo box
206 * @see DefaultComboBoxModel
207 */
208 public JComboBox(Vector<E> items) {
209 super();
210 setModel(new DefaultComboBoxModel<E>(items));
211 init();
212 }
213
214 /**
215 * Creates a <code>JComboBox</code> with a default data model.
216 * The default data model is an empty list of objects.
217 * Use <code>addItem</code> to add items. By default the first item
218 * in the data model becomes selected.
219 *
220 * @see DefaultComboBoxModel
221 */
222 public JComboBox() {
223 super();
224 setModel(new DefaultComboBoxModel<E>());
225 init();
226 }
227
228 private void init() {
229 installAncestorListener();
230 setUIProperty("opaque",true);
231 updateUI();
232 }
233
234 protected void installAncestorListener() {
235 addAncestorListener(new AncestorListener(){
236 public void ancestorAdded(AncestorEvent event){ hidePopup();}
237 public void ancestorRemoved(AncestorEvent event){ hidePopup();}
238 public void ancestorMoved(AncestorEvent event){
239 if (event.getSource() != JComboBox.this)
240 hidePopup();
241 }});
242 }
243
244 /**
245 * Sets the L&F object that renders this component.
246 *
247 * @param ui the <code>ComboBoxUI</code> L&F object
248 * @see UIDefaults#getUI
249 *
250 * @beaninfo
251 * bound: true
252 * hidden: true
253 * attribute: visualUpdate true
254 * description: The UI object that implements the Component's LookAndFeel.
255 */
256 public void setUI(ComboBoxUI ui) {
257 super.setUI(ui);
258 }
259
260 /**
261 * Resets the UI property to a value from the current look and feel.
262 *
263 * @see JComponent#updateUI
264 */
265 public void updateUI() {
266 setUI((ComboBoxUI)UIManager.getUI(this));
267
268 ListCellRenderer<? super E> renderer = getRenderer();
269 if (renderer instanceof Component) {
270 SwingUtilities.updateComponentTreeUI((Component)renderer);
271 }
272 }
273
274
275 /**
276 * Returns the name of the L&F class that renders this component.
277 *
278 * @return the string "ComboBoxUI"
279 * @see JComponent#getUIClassID
280 * @see UIDefaults#getUI
281 */
282 public String getUIClassID() {
283 return uiClassID;
284 }
285
286
287 /**
288 * Returns the L&F object that renders this component.
289 *
290 * @return the ComboBoxUI object that renders this component
291 */
292 public ComboBoxUI getUI() {
293 return(ComboBoxUI)ui;
294 }
295
296 /**
297 * Sets the data model that the <code>JComboBox</code> uses to obtain
298 * the list of items.
299 *
300 * @param aModel the <code>ComboBoxModel</code> that provides the
301 * displayed list of items
302 *
303 * @beaninfo
304 * bound: true
305 * description: Model that the combo box uses to get data to display.
306 */
307 public void setModel(ComboBoxModel<E> aModel) {
308 ComboBoxModel<E> oldModel = dataModel;
309 if (oldModel != null) {
310 oldModel.removeListDataListener(this);
311 }
312 dataModel = aModel;
313 dataModel.addListDataListener(this);
314
315 // set the current selected item.
316 selectedItemReminder = dataModel.getSelectedItem();
317
318 firePropertyChange( "model", oldModel, dataModel);
319 }
320
321 /**
322 * Returns the data model currently used by the <code>JComboBox</code>.
323 *
324 * @return the <code>ComboBoxModel</code> that provides the displayed
325 * list of items
326 */
327 public ComboBoxModel<E> getModel() {
328 return dataModel;
329 }
330
331 /*
332 * Properties
333 */
334
335 /**
336 * Sets the <code>lightWeightPopupEnabled</code> property, which
337 * provides a hint as to whether or not a lightweight
338 * <code>Component</code> should be used to contain the
339 * <code>JComboBox</code>, versus a heavyweight
340 * <code>Component</code> such as a <code>Panel</code>
341 * or a <code>Window</code>. The decision of lightweight
342 * versus heavyweight is ultimately up to the
343 * <code>JComboBox</code>. Lightweight windows are more
344 * efficient than heavyweight windows, but lightweight
345 * and heavyweight components do not mix well in a GUI.
346 * If your application mixes lightweight and heavyweight
347 * components, you should disable lightweight popups.
348 * The default value for the <code>lightWeightPopupEnabled</code>
349 * property is <code>true</code>, unless otherwise specified
350 * by the look and feel. Some look and feels always use
351 * heavyweight popups, no matter what the value of this property.
352 * <p>
353 * See the article <a href="http://www.oracle.com/technetwork/articles/java/mixing-components-433992.html">Mixing Heavy and Light Components</a>
354 * This method fires a property changed event.
355 *
356 * @param aFlag if <code>true</code>, lightweight popups are desired
357 *
358 * @beaninfo
359 * bound: true
360 * expert: true
361 * description: Set to <code>false</code> to require heavyweight popups.
362 */
363 public void setLightWeightPopupEnabled(boolean aFlag) {
364 boolean oldFlag = lightWeightPopupEnabled;
365 lightWeightPopupEnabled = aFlag;
366 firePropertyChange("lightWeightPopupEnabled", oldFlag, lightWeightPopupEnabled);
367 }
368
369 /**
370 * Gets the value of the <code>lightWeightPopupEnabled</code>
371 * property.
372 *
373 * @return the value of the <code>lightWeightPopupEnabled</code>
374 * property
375 * @see #setLightWeightPopupEnabled
376 */
377 public boolean isLightWeightPopupEnabled() {
378 return lightWeightPopupEnabled;
379 }
380
381 /**
382 * Determines whether the <code>JComboBox</code> field is editable.
383 * An editable <code>JComboBox</code> allows the user to type into the
384 * field or selected an item from the list to initialize the field,
385 * after which it can be edited. (The editing affects only the field,
386 * the list item remains intact.) A non editable <code>JComboBox</code>
387 * displays the selected item in the field,
388 * but the selection cannot be modified.
389 *
390 * @param aFlag a boolean value, where true indicates that the
391 * field is editable
392 *
393 * @beaninfo
394 * bound: true
395 * preferred: true
396 * description: If true, the user can type a new value in the combo box.
397 */
398 public void setEditable(boolean aFlag) {
399 boolean oldFlag = isEditable;
400 isEditable = aFlag;
401 firePropertyChange( "editable", oldFlag, isEditable );
402 }
403
404 /**
405 * Returns true if the <code>JComboBox</code> is editable.
406 * By default, a combo box is not editable.
407 *
408 * @return true if the <code>JComboBox</code> is editable, else false
409 */
410 public boolean isEditable() {
411 return isEditable;
412 }
413
414 /**
415 * Sets the maximum number of rows the <code>JComboBox</code> displays.
416 * If the number of objects in the model is greater than count,
417 * the combo box uses a scrollbar.
418 *
419 * @param count an integer specifying the maximum number of items to
420 * display in the list before using a scrollbar
421 * @beaninfo
422 * bound: true
423 * preferred: true
424 * description: The maximum number of rows the popup should have
425 */
426 public void setMaximumRowCount(int count) {
427 int oldCount = maximumRowCount;
428 maximumRowCount = count;
429 firePropertyChange( "maximumRowCount", oldCount, maximumRowCount );
430 }
431
432 /**
433 * Returns the maximum number of items the combo box can display
434 * without a scrollbar
435 *
436 * @return an integer specifying the maximum number of items that are
437 * displayed in the list before using a scrollbar
438 */
439 public int getMaximumRowCount() {
440 return maximumRowCount;
441 }
442
443 /**
444 * Sets the renderer that paints the list items and the item selected from the list in
445 * the JComboBox field. The renderer is used if the JComboBox is not
446 * editable. If it is editable, the editor is used to render and edit
447 * the selected item.
448 * <p>
449 * The default renderer displays a string or an icon.
450 * Other renderers can handle graphic images and composite items.
451 * <p>
452 * To display the selected item,
453 * <code>aRenderer.getListCellRendererComponent</code>
454 * is called, passing the list object and an index of -1.
455 *
456 * @param aRenderer the <code>ListCellRenderer</code> that
457 * displays the selected item
458 * @see #setEditor
459 * @beaninfo
460 * bound: true
461 * expert: true
462 * description: The renderer that paints the item selected in the list.
463 */
464 public void setRenderer(ListCellRenderer<? super E> aRenderer) {
465 ListCellRenderer<? super E> oldRenderer = renderer;
466 renderer = aRenderer;
467 firePropertyChange( "renderer", oldRenderer, renderer );
468 invalidate();
469 }
470
471 /**
472 * Returns the renderer used to display the selected item in the
473 * <code>JComboBox</code> field.
474 *
475 * @return the <code>ListCellRenderer</code> that displays
476 * the selected item.
477 */
478 public ListCellRenderer<? super E> getRenderer() {
479 return renderer;
480 }
481
482 /**
483 * Sets the editor used to paint and edit the selected item in the
484 * <code>JComboBox</code> field. The editor is used only if the
485 * receiving <code>JComboBox</code> is editable. If not editable,
486 * the combo box uses the renderer to paint the selected item.
487 *
488 * @param anEditor the <code>ComboBoxEditor</code> that
489 * displays the selected item
490 * @see #setRenderer
491 * @beaninfo
492 * bound: true
493 * expert: true
494 * description: The editor that combo box uses to edit the current value
495 */
496 public void setEditor(ComboBoxEditor anEditor) {
497 ComboBoxEditor oldEditor = editor;
498
499 if ( editor != null ) {
500 editor.removeActionListener(this);
501 }
502 editor = anEditor;
503 if ( editor != null ) {
504 editor.addActionListener(this);
505 }
506 firePropertyChange( "editor", oldEditor, editor );
507 }
508
509 /**
510 * Returns the editor used to paint and edit the selected item in the
511 * <code>JComboBox</code> field.
512 *
513 * @return the <code>ComboBoxEditor</code> that displays the selected item
514 */
515 public ComboBoxEditor getEditor() {
516 return editor;
517 }
518
519 //
520 // Selection
521 //
522
523 /**
524 * Sets the selected item in the combo box display area to the object in
525 * the argument.
526 * If <code>anObject</code> is in the list, the display area shows
527 * <code>anObject</code> selected.
528 * <p>
529 * If <code>anObject</code> is <i>not</i> in the list and the combo box is
530 * uneditable, it will not change the current selection. For editable
531 * combo boxes, the selection will change to <code>anObject</code>.
532 * <p>
533 * If this constitutes a change in the selected item,
534 * <code>ItemListener</code>s added to the combo box will be notified with
535 * one or two <code>ItemEvent</code>s.
536 * If there is a current selected item, an <code>ItemEvent</code> will be
537 * fired and the state change will be <code>ItemEvent.DESELECTED</code>.
538 * If <code>anObject</code> is in the list and is not currently selected
539 * then an <code>ItemEvent</code> will be fired and the state change will
540 * be <code>ItemEvent.SELECTED</code>.
541 * <p>
542 * <code>ActionListener</code>s added to the combo box will be notified
543 * with an <code>ActionEvent</code> when this method is called.
544 *
545 * @param anObject the list object to select; use <code>null</code> to
546 clear the selection
547 * @beaninfo
548 * preferred: true
549 * description: Sets the selected item in the JComboBox.
550 */
551 public void setSelectedItem(Object anObject) {
552 Object oldSelection = selectedItemReminder;
553 Object objectToSelect = anObject;
554 if (oldSelection == null || !oldSelection.equals(anObject)) {
555
556 if (anObject != null && !isEditable()) {
557 // For non editable combo boxes, an invalid selection
558 // will be rejected.
559 boolean found = false;
560 for (int i = 0; i < dataModel.getSize(); i++) {
561 E element = dataModel.getElementAt(i);
562 if (anObject.equals(element)) {
563 found = true;
564 objectToSelect = element;
565 break;
566 }
567 }
568 if (!found) {
569 return;
570 }
571 }
572
573 // Must toggle the state of this flag since this method
574 // call may result in ListDataEvents being fired.
575 selectingItem = true;
576 dataModel.setSelectedItem(objectToSelect);
577 selectingItem = false;
578
579 if (selectedItemReminder != dataModel.getSelectedItem()) {
580 // in case a users implementation of ComboBoxModel
581 // doesn't fire a ListDataEvent when the selection
582 // changes.
583 selectedItemChanged();
584 }
585 }
586 fireActionEvent();
587 }
588
589 /**
590 * Returns the current selected item.
591 * <p>
592 * If the combo box is editable, then this value may not have been added
593 * to the combo box with <code>addItem</code>, <code>insertItemAt</code>
594 * or the data constructors.
595 *
596 * @return the current selected Object
597 * @see #setSelectedItem
598 */
599 public Object getSelectedItem() {
600 return dataModel.getSelectedItem();
601 }
602
603 /**
604 * Selects the item at index <code>anIndex</code>.
605 *
606 * @param anIndex an integer specifying the list item to select,
607 * where 0 specifies the first item in the list and -1 indicates no selection
608 * @exception IllegalArgumentException if <code>anIndex</code> < -1 or
609 * <code>anIndex</code> is greater than or equal to size
610 * @beaninfo
611 * preferred: true
612 * description: The item at index is selected.
613 */
614 public void setSelectedIndex(int anIndex) {
615 int size = dataModel.getSize();
616
617 if ( anIndex == -1 ) {
618 setSelectedItem( null );
619 } else if ( anIndex < -1 || anIndex >= size ) {
620 throw new IllegalArgumentException("setSelectedIndex: " + anIndex + " out of bounds");
621 } else {
622 setSelectedItem(dataModel.getElementAt(anIndex));
623 }
624 }
625
626 /**
627 * Returns the first item in the list that matches the given item.
628 * The result is not always defined if the <code>JComboBox</code>
629 * allows selected items that are not in the list.
630 * Returns -1 if there is no selected item or if the user specified
631 * an item which is not in the list.
632
633 * @return an integer specifying the currently selected list item,
634 * where 0 specifies
635 * the first item in the list;
636 * or -1 if no item is selected or if
637 * the currently selected item is not in the list
638 */
639 @Transient
640 public int getSelectedIndex() {
641 Object sObject = dataModel.getSelectedItem();
642 int i,c;
643 E obj;
644
645 for ( i=0,c=dataModel.getSize();i<c;i++ ) {
646 obj = dataModel.getElementAt(i);
647 if ( obj != null && obj.equals(sObject) )
648 return i;
649 }
650 return -1;
651 }
652
653 /**
654 * Returns the "prototypical display" value - an Object used
655 * for the calculation of the display height and width.
656 *
657 * @return the value of the <code>prototypeDisplayValue</code> property
658 * @see #setPrototypeDisplayValue
659 * @since 1.4
660 */
661 public E getPrototypeDisplayValue() {
662 return prototypeDisplayValue;
663 }
664
665 /**
666 * Sets the prototype display value used to calculate the size of the display
667 * for the UI portion.
668 * <p>
669 * If a prototype display value is specified, the preferred size of
670 * the combo box is calculated by configuring the renderer with the
671 * prototype display value and obtaining its preferred size. Specifying
672 * the preferred display value is often useful when the combo box will be
673 * displaying large amounts of data. If no prototype display value has
674 * been specified, the renderer must be configured for each value from
675 * the model and its preferred size obtained, which can be
676 * relatively expensive.
677 *
678 * @param prototypeDisplayValue
679 * @see #getPrototypeDisplayValue
680 * @since 1.4
681 * @beaninfo
682 * bound: true
683 * attribute: visualUpdate true
684 * description: The display prototype value, used to compute display width and height.
685 */
686 public void setPrototypeDisplayValue(E prototypeDisplayValue) {
687 Object oldValue = this.prototypeDisplayValue;
688 this.prototypeDisplayValue = prototypeDisplayValue;
689 firePropertyChange("prototypeDisplayValue", oldValue, prototypeDisplayValue);
690 }
691
692 /**
693 * Adds an item to the item list.
694 * This method works only if the <code>JComboBox</code> uses a
695 * mutable data model.
696 * <p>
697 * <strong>Warning:</strong>
698 * Focus and keyboard navigation problems may arise if you add duplicate
699 * String objects. A workaround is to add new objects instead of String
700 * objects and make sure that the toString() method is defined.
701 * For example:
702 * <pre>
703 * comboBox.addItem(makeObj("Item 1"));
704 * comboBox.addItem(makeObj("Item 1"));
705 * ...
706 * private Object makeObj(final String item) {
707 * return new Object() { public String toString() { return item; } };
708 * }
709 * </pre>
710 *
711 * @param item the item to add to the list
712 * @see MutableComboBoxModel
713 */
714 public void addItem(E item) {
715 checkMutableComboBoxModel();
716 ((MutableComboBoxModel<E>)dataModel).addElement(item);
717 }
718
719 /**
720 * Inserts an item into the item list at a given index.
721 * This method works only if the <code>JComboBox</code> uses a
722 * mutable data model.
723 *
724 * @param item the item to add to the list
725 * @param index an integer specifying the position at which
726 * to add the item
727 * @see MutableComboBoxModel
728 */
729 public void insertItemAt(E item, int index) {
730 checkMutableComboBoxModel();
731 ((MutableComboBoxModel<E>)dataModel).insertElementAt(item,index);
732 }
733
734 /**
735 * Removes an item from the item list.
736 * This method works only if the <code>JComboBox</code> uses a
737 * mutable data model.
738 *
739 * @param anObject the object to remove from the item list
740 * @see MutableComboBoxModel
741 */
742 public void removeItem(Object anObject) {
743 checkMutableComboBoxModel();
744 ((MutableComboBoxModel)dataModel).removeElement(anObject);
745 }
746
747 /**
748 * Removes the item at <code>anIndex</code>
749 * This method works only if the <code>JComboBox</code> uses a
750 * mutable data model.
751 *
752 * @param anIndex an int specifying the index of the item to remove,
753 * where 0
754 * indicates the first item in the list
755 * @see MutableComboBoxModel
756 */
757 public void removeItemAt(int anIndex) {
758 checkMutableComboBoxModel();
759 ((MutableComboBoxModel<E>)dataModel).removeElementAt( anIndex );
760 }
761
762 /**
763 * Removes all items from the item list.
764 */
765 public void removeAllItems() {
766 checkMutableComboBoxModel();
767 MutableComboBoxModel<E> model = (MutableComboBoxModel<E>)dataModel;
768 int size = model.getSize();
769
770 if ( model instanceof DefaultComboBoxModel ) {
771 ((DefaultComboBoxModel)model).removeAllElements();
772 }
773 else {
774 for ( int i = 0; i < size; ++i ) {
775 E element = model.getElementAt( 0 );
776 model.removeElement( element );
777 }
778 }
779 selectedItemReminder = null;
780 if (isEditable()) {
781 editor.setItem(null);
782 }
783 }
784
785 /**
786 * Checks that the <code>dataModel</code> is an instance of
787 * <code>MutableComboBoxModel</code>. If not, it throws an exception.
788 * @exception RuntimeException if <code>dataModel</code> is not an
789 * instance of <code>MutableComboBoxModel</code>.
790 */
791 void checkMutableComboBoxModel() {
792 if ( !(dataModel instanceof MutableComboBoxModel) )
793 throw new RuntimeException("Cannot use this method with a non-Mutable data model.");
794 }
795
796 /**
797 * Causes the combo box to display its popup window.
798 * @see #setPopupVisible
799 */
800 public void showPopup() {
801 setPopupVisible(true);
802 }
803
804 /**
805 * Causes the combo box to close its popup window.
806 * @see #setPopupVisible
807 */
808 public void hidePopup() {
809 setPopupVisible(false);
810 }
811
812 /**
813 * Sets the visibility of the popup.
814 */
815 public void setPopupVisible(boolean v) {
816 getUI().setPopupVisible(this, v);
817 }
818
819 /**
820 * Determines the visibility of the popup.
821 *
822 * @return true if the popup is visible, otherwise returns false
823 */
824 public boolean isPopupVisible() {
825 return getUI().isPopupVisible(this);
826 }
827
828 /** Selection **/
829
830 /**
831 * Adds an <code>ItemListener</code>.
832 * <p>
833 * <code>aListener</code> will receive one or two <code>ItemEvent</code>s when
834 * the selected item changes.
835 *
836 * @param aListener the <code>ItemListener</code> that is to be notified
837 * @see #setSelectedItem
838 */
839 public void addItemListener(ItemListener aListener) {
840 listenerList.add(ItemListener.class,aListener);
841 }
842
843 /** Removes an <code>ItemListener</code>.
844 *
845 * @param aListener the <code>ItemListener</code> to remove
846 */
847 public void removeItemListener(ItemListener aListener) {
848 listenerList.remove(ItemListener.class,aListener);
849 }
850
851 /**
852 * Returns an array of all the <code>ItemListener</code>s added
853 * to this JComboBox with addItemListener().
854 *
855 * @return all of the <code>ItemListener</code>s added or an empty
856 * array if no listeners have been added
857 * @since 1.4
858 */
859 public ItemListener[] getItemListeners() {
860 return listenerList.getListeners(ItemListener.class);
861 }
862
863 /**
864 * Adds an <code>ActionListener</code>.
865 * <p>
866 * The <code>ActionListener</code> will receive an <code>ActionEvent</code>
867 * when a selection has been made. If the combo box is editable, then
868 * an <code>ActionEvent</code> will be fired when editing has stopped.
869 *
870 * @param l the <code>ActionListener</code> that is to be notified
871 * @see #setSelectedItem
872 */
873 public void addActionListener(ActionListener l) {
874 listenerList.add(ActionListener.class,l);
875 }
876
877 /** Removes an <code>ActionListener</code>.
878 *
879 * @param l the <code>ActionListener</code> to remove
880 */
881 public void removeActionListener(ActionListener l) {
882 if ((l != null) && (getAction() == l)) {
883 setAction(null);
884 } else {
885 listenerList.remove(ActionListener.class, l);
886 }
887 }
888
889 /**
890 * Returns an array of all the <code>ActionListener</code>s added
891 * to this JComboBox with addActionListener().
892 *
893 * @return all of the <code>ActionListener</code>s added or an empty
894 * array if no listeners have been added
895 * @since 1.4
896 */
897 public ActionListener[] getActionListeners() {
898 return listenerList.getListeners(ActionListener.class);
899 }
900
901 /**
902 * Adds a <code>PopupMenu</code> listener which will listen to notification
903 * messages from the popup portion of the combo box.
904 * <p>
905 * For all standard look and feels shipped with Java, the popup list
906 * portion of combo box is implemented as a <code>JPopupMenu</code>.
907 * A custom look and feel may not implement it this way and will
908 * therefore not receive the notification.
909 *
910 * @param l the <code>PopupMenuListener</code> to add
911 * @since 1.4
912 */
913 public void addPopupMenuListener(PopupMenuListener l) {
914 listenerList.add(PopupMenuListener.class,l);
915 }
916
917 /**
918 * Removes a <code>PopupMenuListener</code>.
919 *
920 * @param l the <code>PopupMenuListener</code> to remove
921 * @see #addPopupMenuListener
922 * @since 1.4
923 */
924 public void removePopupMenuListener(PopupMenuListener l) {
925 listenerList.remove(PopupMenuListener.class,l);
926 }
927
928 /**
929 * Returns an array of all the <code>PopupMenuListener</code>s added
930 * to this JComboBox with addPopupMenuListener().
931 *
932 * @return all of the <code>PopupMenuListener</code>s added or an empty
933 * array if no listeners have been added
934 * @since 1.4
935 */
936 public PopupMenuListener[] getPopupMenuListeners() {
937 return listenerList.getListeners(PopupMenuListener.class);
938 }
939
940 /**
941 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
942 * combo box will become visible.
943 * <p>
944 * This method is public but should not be called by anything other than
945 * the UI delegate.
946 * @see #addPopupMenuListener
947 * @since 1.4
948 */
949 public void firePopupMenuWillBecomeVisible() {
950 Object[] listeners = listenerList.getListenerList();
951 PopupMenuEvent e=null;
952 for (int i = listeners.length-2; i>=0; i-=2) {
953 if (listeners[i]==PopupMenuListener.class) {
954 if (e == null)
955 e = new PopupMenuEvent(this);
956 ((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeVisible(e);
957 }
958 }
959 }
960
961 /**
962 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
963 * combo box has become invisible.
964 * <p>
965 * This method is public but should not be called by anything other than
966 * the UI delegate.
967 * @see #addPopupMenuListener
968 * @since 1.4
969 */
970 public void firePopupMenuWillBecomeInvisible() {
971 Object[] listeners = listenerList.getListenerList();
972 PopupMenuEvent e=null;
973 for (int i = listeners.length-2; i>=0; i-=2) {
974 if (listeners[i]==PopupMenuListener.class) {
975 if (e == null)
976 e = new PopupMenuEvent(this);
977 ((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeInvisible(e);
978 }
979 }
980 }
981
982 /**
983 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
984 * combo box has been canceled.
985 * <p>
986 * This method is public but should not be called by anything other than
987 * the UI delegate.
988 * @see #addPopupMenuListener
989 * @since 1.4
990 */
991 public void firePopupMenuCanceled() {
992 Object[] listeners = listenerList.getListenerList();
993 PopupMenuEvent e=null;
994 for (int i = listeners.length-2; i>=0; i-=2) {
995 if (listeners[i]==PopupMenuListener.class) {
996 if (e == null)
997 e = new PopupMenuEvent(this);
998 ((PopupMenuListener)listeners[i+1]).popupMenuCanceled(e);
999 }
1000 }
1001 }
1002
1003 /**
1004 * Sets the action command that should be included in the event
1005 * sent to action listeners.
1006 *
1007 * @param aCommand a string containing the "command" that is sent
1008 * to action listeners; the same listener can then
1009 * do different things depending on the command it
1010 * receives
1011 */
1012 public void setActionCommand(String aCommand) {
1013 actionCommand = aCommand;
1014 }
1015
1016 /**
1017 * Returns the action command that is included in the event sent to
1018 * action listeners.
1019 *
1020 * @return the string containing the "command" that is sent
1021 * to action listeners.
1022 */
1023 public String getActionCommand() {
1024 return actionCommand;
1025 }
1026
1027 private Action action;
1028 private PropertyChangeListener actionPropertyChangeListener;
1029
1030 /**
1031 * Sets the <code>Action</code> for the <code>ActionEvent</code> source.
1032 * The new <code>Action</code> replaces any previously set
1033 * <code>Action</code> but does not affect <code>ActionListeners</code>
1034 * independently added with <code>addActionListener</code>.
1035 * If the <code>Action</code> is already a registered
1036 * <code>ActionListener</code> for the <code>ActionEvent</code> source,
1037 * it is not re-registered.
1038 * <p>
1039 * Setting the <code>Action</code> results in immediately changing
1040 * all the properties described in <a href="Action.html#buttonActions">
1041 * Swing Components Supporting <code>Action</code></a>.
1042 * Subsequently, the combobox's properties are automatically updated
1043 * as the <code>Action</code>'s properties change.
1044 * <p>
1045 * This method uses three other methods to set
1046 * and help track the <code>Action</code>'s property values.
1047 * It uses the <code>configurePropertiesFromAction</code> method
1048 * to immediately change the combobox's properties.
1049 * To track changes in the <code>Action</code>'s property values,
1050 * this method registers the <code>PropertyChangeListener</code>
1051 * returned by <code>createActionPropertyChangeListener</code>. The
1052 * default {@code PropertyChangeListener} invokes the
1053 * {@code actionPropertyChanged} method when a property in the
1054 * {@code Action} changes.
1055 *
1056 * @param a the <code>Action</code> for the <code>JComboBox</code>,
1057 * or <code>null</code>.
1058 * @since 1.3
1059 * @see Action
1060 * @see #getAction
1061 * @see #configurePropertiesFromAction
1062 * @see #createActionPropertyChangeListener
1063 * @see #actionPropertyChanged
1064 * @beaninfo
1065 * bound: true
1066 * attribute: visualUpdate true
1067 * description: the Action instance connected with this ActionEvent source
1068 */
1069 public void setAction(Action a) {
1070 Action oldValue = getAction();
1071 if (action==null || !action.equals(a)) {
1072 action = a;
1073 if (oldValue!=null) {
1074 removeActionListener(oldValue);
1075 oldValue.removePropertyChangeListener(actionPropertyChangeListener);
1076 actionPropertyChangeListener = null;
1077 }
1078 configurePropertiesFromAction(action);
1079 if (action!=null) {
1080 // Don't add if it is already a listener
1081 if (!isListener(ActionListener.class, action)) {
1082 addActionListener(action);
1083 }
1084 // Reverse linkage:
1085 actionPropertyChangeListener = createActionPropertyChangeListener(action);
1086 action.addPropertyChangeListener(actionPropertyChangeListener);
1087 }
1088 firePropertyChange("action", oldValue, action);
1089 }
1090 }
1091
1092 private boolean isListener(Class c, ActionListener a) {
1093 boolean isListener = false;
1094 Object[] listeners = listenerList.getListenerList();
1095 for (int i = listeners.length-2; i>=0; i-=2) {
1096 if (listeners[i]==c && listeners[i+1]==a) {
1097 isListener=true;
1098 }
1099 }
1100 return isListener;
1101 }
1102
1103 /**
1104 * Returns the currently set <code>Action</code> for this
1105 * <code>ActionEvent</code> source, or <code>null</code> if no
1106 * <code>Action</code> is set.
1107 *
1108 * @return the <code>Action</code> for this <code>ActionEvent</code>
1109 * source; or <code>null</code>
1110 * @since 1.3
1111 * @see Action
1112 * @see #setAction
1113 */
1114 public Action getAction() {
1115 return action;
1116 }
1117
1118 /**
1119 * Sets the properties on this combobox to match those in the specified
1120 * <code>Action</code>. Refer to <a href="Action.html#buttonActions">
1121 * Swing Components Supporting <code>Action</code></a> for more
1122 * details as to which properties this sets.
1123 *
1124 * @param a the <code>Action</code> from which to get the properties,
1125 * or <code>null</code>
1126 * @since 1.3
1127 * @see Action
1128 * @see #setAction
1129 */
1130 protected void configurePropertiesFromAction(Action a) {
1131 AbstractAction.setEnabledFromAction(this, a);
1132 AbstractAction.setToolTipTextFromAction(this, a);
1133 setActionCommandFromAction(a);
1134 }
1135
1136 /**
1137 * Creates and returns a <code>PropertyChangeListener</code> that is
1138 * responsible for listening for changes from the specified
1139 * <code>Action</code> and updating the appropriate properties.
1140 * <p>
1141 * <b>Warning:</b> If you subclass this do not create an anonymous
1142 * inner class. If you do the lifetime of the combobox will be tied to
1143 * that of the <code>Action</code>.
1144 *
1145 * @param a the combobox's action
1146 * @since 1.3
1147 * @see Action
1148 * @see #setAction
1149 */
1150 protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
1151 return new ComboBoxActionPropertyChangeListener(this, a);
1152 }
1153
1154 /**
1155 * Updates the combobox's state in response to property changes in
1156 * associated action. This method is invoked from the
1157 * {@code PropertyChangeListener} returned from
1158 * {@code createActionPropertyChangeListener}. Subclasses do not normally
1159 * need to invoke this. Subclasses that support additional {@code Action}
1160 * properties should override this and
1161 * {@code configurePropertiesFromAction}.
1162 * <p>
1163 * Refer to the table at <a href="Action.html#buttonActions">
1164 * Swing Components Supporting <code>Action</code></a> for a list of
1165 * the properties this method sets.
1166 *
1167 * @param action the <code>Action</code> associated with this combobox
1168 * @param propertyName the name of the property that changed
1169 * @since 1.6
1170 * @see Action
1171 * @see #configurePropertiesFromAction
1172 */
1173 protected void actionPropertyChanged(Action action, String propertyName) {
1174 if (propertyName == Action.ACTION_COMMAND_KEY) {
1175 setActionCommandFromAction(action);
1176 } else if (propertyName == "enabled") {
1177 AbstractAction.setEnabledFromAction(this, action);
1178 } else if (Action.SHORT_DESCRIPTION == propertyName) {
1179 AbstractAction.setToolTipTextFromAction(this, action);
1180 }
1181 }
1182
1183 private void setActionCommandFromAction(Action a) {
1184 setActionCommand((a != null) ?
1185 (String)a.getValue(Action.ACTION_COMMAND_KEY) :
1186 null);
1187 }
1188
1189
1190 private static class ComboBoxActionPropertyChangeListener
1191 extends ActionPropertyChangeListener<JComboBox<?>> {
1192 ComboBoxActionPropertyChangeListener(JComboBox<?> b, Action a) {
1193 super(b, a);
1194 }
1195 protected void actionPropertyChanged(JComboBox<?> cb,
1196 Action action,
1197 PropertyChangeEvent e) {
1198 if (AbstractAction.shouldReconfigure(e)) {
1199 cb.configurePropertiesFromAction(action);
1200 } else {
1201 cb.actionPropertyChanged(action, e.getPropertyName());
1202 }
1203 }
1204 }
1205
1206 /**
1207 * Notifies all listeners that have registered interest for
1208 * notification on this event type.
1209 * @param e the event of interest
1210 *
1211 * @see EventListenerList
1212 */
1213 protected void fireItemStateChanged(ItemEvent e) {
1214 // Guaranteed to return a non-null array
1215 Object[] listeners = listenerList.getListenerList();
1216 // Process the listeners last to first, notifying
1217 // those that are interested in this event
1218 for ( int i = listeners.length-2; i>=0; i-=2 ) {
1219 if ( listeners[i]==ItemListener.class ) {
1220 // Lazily create the event:
1221 // if (changeEvent == null)
1222 // changeEvent = new ChangeEvent(this);
1223 ((ItemListener)listeners[i+1]).itemStateChanged(e);
1224 }
1225 }
1226 }
1227
1228 /**
1229 * Notifies all listeners that have registered interest for
1230 * notification on this event type.
1231 *
1232 * @see EventListenerList
1233 */
1234 protected void fireActionEvent() {
1235 if (!firingActionEvent) {
1236 // Set flag to ensure that an infinite loop is not created
1237 firingActionEvent = true;
1238 ActionEvent e = null;
1239 // Guaranteed to return a non-null array
1240 Object[] listeners = listenerList.getListenerList();
1241 long mostRecentEventTime = EventQueue.getMostRecentEventTime();
1242 int modifiers = 0;
1243 AWTEvent currentEvent = EventQueue.getCurrentEvent();
1244 if (currentEvent instanceof InputEvent) {
1245 modifiers = ((InputEvent)currentEvent).getModifiers();
1246 } else if (currentEvent instanceof ActionEvent) {
1247 modifiers = ((ActionEvent)currentEvent).getModifiers();
1248 }
1249 // Process the listeners last to first, notifying
1250 // those that are interested in this event
1251 for ( int i = listeners.length-2; i>=0; i-=2 ) {
1252 if ( listeners[i]==ActionListener.class ) {
1253 // Lazily create the event:
1254 if ( e == null )
1255 e = new ActionEvent(this,ActionEvent.ACTION_PERFORMED,
1256 getActionCommand(),
1257 mostRecentEventTime, modifiers);
1258 ((ActionListener)listeners[i+1]).actionPerformed(e);
1259 }
1260 }
1261 firingActionEvent = false;
1262 }
1263 }
1264
1265 /**
1266 * This protected method is implementation specific. Do not access directly
1267 * or override.
1268 */
1269 protected void selectedItemChanged() {
1270 if (selectedItemReminder != null ) {
1271 fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
1272 selectedItemReminder,
1273 ItemEvent.DESELECTED));
1274 }
1275
1276 // set the new selected item.
1277 selectedItemReminder = dataModel.getSelectedItem();
1278
1279 if (selectedItemReminder != null ) {
1280 fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
1281 selectedItemReminder,
1282 ItemEvent.SELECTED));
1283 }
1284 }
1285
1286 /**
1287 * Returns an array containing the selected item.
1288 * This method is implemented for compatibility with
1289 * <code>ItemSelectable</code>.
1290 *
1291 * @return an array of <code>Objects</code> containing one
1292 * element -- the selected item
1293 */
1294 public Object[] getSelectedObjects() {
1295 Object selectedObject = getSelectedItem();
1296 if ( selectedObject == null )
1297 return new Object[0];
1298 else {
1299 Object result[] = new Object[1];
1300 result[0] = selectedObject;
1301 return result;
1302 }
1303 }
1304
1305 /**
1306 * This method is public as an implementation side effect.
1307 * do not call or override.
1308 */
1309 public void actionPerformed(ActionEvent e) {
1310 Object newItem = getEditor().getItem();
1311 setPopupVisible(false);
1312 getModel().setSelectedItem(newItem);
1313 String oldCommand = getActionCommand();
1314 setActionCommand("comboBoxEdited");
1315 fireActionEvent();
1316 setActionCommand(oldCommand);
1317 }
1318
1319 /**
1320 * This method is public as an implementation side effect.
1321 * do not call or override.
1322 */
1323 public void contentsChanged(ListDataEvent e) {
1324 Object oldSelection = selectedItemReminder;
1325 Object newSelection = dataModel.getSelectedItem();
1326 if (oldSelection == null || !oldSelection.equals(newSelection)) {
1327 selectedItemChanged();
1328 if (!selectingItem) {
1329 fireActionEvent();
1330 }
1331 }
1332 }
1333
1334 /**
1335 * This method is public as an implementation side effect.
1336 * do not call or override.
1337 */
1338 public void intervalAdded(ListDataEvent e) {
1339 if (selectedItemReminder != dataModel.getSelectedItem()) {
1340 selectedItemChanged();
1341 }
1342 }
1343
1344 /**
1345 * This method is public as an implementation side effect.
1346 * do not call or override.
1347 */
1348 public void intervalRemoved(ListDataEvent e) {
1349 contentsChanged(e);
1350 }
1351
1352 /**
1353 * Selects the list item that corresponds to the specified keyboard
1354 * character and returns true, if there is an item corresponding
1355 * to that character. Otherwise, returns false.
1356 *
1357 * @param keyChar a char, typically this is a keyboard key
1358 * typed by the user
1359 */
1360 public boolean selectWithKeyChar(char keyChar) {
1361 int index;
1362
1363 if ( keySelectionManager == null )
1364 keySelectionManager = createDefaultKeySelectionManager();
1365
1366 index = keySelectionManager.selectionForKey(keyChar,getModel());
1367 if ( index != -1 ) {
1368 setSelectedIndex(index);
1369 return true;
1370 }
1371 else
1372 return false;
1373 }
1374
1375 /**
1376 * Enables the combo box so that items can be selected. When the
1377 * combo box is disabled, items cannot be selected and values
1378 * cannot be typed into its field (if it is editable).
1379 *
1380 * @param b a boolean value, where true enables the component and
1381 * false disables it
1382 * @beaninfo
1383 * bound: true
1384 * preferred: true
1385 * description: Whether the combo box is enabled.
1386 */
1387 public void setEnabled(boolean b) {
1388 super.setEnabled(b);
1389 firePropertyChange( "enabled", !isEnabled(), isEnabled() );
1390 }
1391
1392 /**
1393 * Initializes the editor with the specified item.
1394 *
1395 * @param anEditor the <code>ComboBoxEditor</code> that displays
1396 * the list item in the
1397 * combo box field and allows it to be edited
1398 * @param anItem the object to display and edit in the field
1399 */
1400 public void configureEditor(ComboBoxEditor anEditor, Object anItem) {
1401 anEditor.setItem(anItem);
1402 }
1403
1404 /**
1405 * Handles <code>KeyEvent</code>s, looking for the Tab key.
1406 * If the Tab key is found, the popup window is closed.
1407 *
1408 * @param e the <code>KeyEvent</code> containing the keyboard
1409 * key that was pressed
1410 */
1411 public void processKeyEvent(KeyEvent e) {
1412 if ( e.getKeyCode() == KeyEvent.VK_TAB ) {
1413 hidePopup();
1414 }
1415 super.processKeyEvent(e);
1416 }
1417
1418 /**
1419 * Sets the object that translates a keyboard character into a list
1420 * selection. Typically, the first selection with a matching first
1421 * character becomes the selected item.
1422 *
1423 * @beaninfo
1424 * expert: true
1425 * description: The objects that changes the selection when a key is pressed.
1426 */
1427 public void setKeySelectionManager(KeySelectionManager aManager) {
1428 keySelectionManager = aManager;
1429 }
1430
1431 /**
1432 * Returns the list's key-selection manager.
1433 *
1434 * @return the <code>KeySelectionManager</code> currently in use
1435 */
1436 public KeySelectionManager getKeySelectionManager() {
1437 return keySelectionManager;
1438 }
1439
1440 /* Accessing the model */
1441 /**
1442 * Returns the number of items in the list.
1443 *
1444 * @return an integer equal to the number of items in the list
1445 */
1446 public int getItemCount() {
1447 return dataModel.getSize();
1448 }
1449
1450 /**
1451 * Returns the list item at the specified index. If <code>index</code>
1452 * is out of range (less than zero or greater than or equal to size)
1453 * it will return <code>null</code>.
1454 *
1455 * @param index an integer indicating the list position, where the first
1456 * item starts at zero
1457 * @return the item at that list position; or
1458 * <code>null</code> if out of range
1459 */
1460 public E getItemAt(int index) {
1461 return dataModel.getElementAt(index);
1462 }
1463
1464 /**
1465 * Returns an instance of the default key-selection manager.
1466 *
1467 * @return the <code>KeySelectionManager</code> currently used by the list
1468 * @see #setKeySelectionManager
1469 */
1470 protected KeySelectionManager createDefaultKeySelectionManager() {
1471 return new DefaultKeySelectionManager();
1472 }
1473
1474
1475 /**
1476 * The interface that defines a <code>KeySelectionManager</code>.
1477 * To qualify as a <code>KeySelectionManager</code>,
1478 * the class needs to implement the method
1479 * that identifies the list index given a character and the
1480 * combo box data model.
1481 */
1482 public interface KeySelectionManager {
1483 /** Given <code>aKey</code> and the model, returns the row
1484 * that should become selected. Return -1 if no match was
1485 * found.
1486 *
1487 * @param aKey a char value, usually indicating a keyboard key that
1488 * was pressed
1489 * @param aModel a ComboBoxModel -- the component's data model, containing
1490 * the list of selectable items
1491 * @return an int equal to the selected row, where 0 is the
1492 * first item and -1 is none.
1493 */
1494 int selectionForKey(char aKey,ComboBoxModel aModel);
1495 }
1496
1497 class DefaultKeySelectionManager implements KeySelectionManager, Serializable {
1498 public int selectionForKey(char aKey,ComboBoxModel aModel) {
1499 int i,c;
1500 int currentSelection = -1;
1501 Object selectedItem = aModel.getSelectedItem();
1502 String v;
1503 String pattern;
1504
1505 if ( selectedItem != null ) {
1506 for ( i=0,c=aModel.getSize();i<c;i++ ) {
1507 if ( selectedItem == aModel.getElementAt(i) ) {
1508 currentSelection = i;
1509 break;
1510 }
1511 }
1512 }
1513
1514 pattern = ("" + aKey).toLowerCase();
1515 aKey = pattern.charAt(0);
1516
1517 for ( i = ++currentSelection, c = aModel.getSize() ; i < c ; i++ ) {
1518 Object elem = aModel.getElementAt(i);
1519 if (elem != null && elem.toString() != null) {
1520 v = elem.toString().toLowerCase();
1521 if ( v.length() > 0 && v.charAt(0) == aKey )
1522 return i;
1523 }
1524 }
1525
1526 for ( i = 0 ; i < currentSelection ; i ++ ) {
1527 Object elem = aModel.getElementAt(i);
1528 if (elem != null && elem.toString() != null) {
1529 v = elem.toString().toLowerCase();
1530 if ( v.length() > 0 && v.charAt(0) == aKey )
1531 return i;
1532 }
1533 }
1534 return -1;
1535 }
1536 }
1537
1538
1539 /**
1540 * See <code>readObject</code> and <code>writeObject</code> in
1541 * <code>JComponent</code> for more
1542 * information about serialization in Swing.
1543 */
1544 private void writeObject(ObjectOutputStream s) throws IOException {
1545 s.defaultWriteObject();
1546 if (getUIClassID().equals(uiClassID)) {
1547 byte count = JComponent.getWriteObjCounter(this);
1548 JComponent.setWriteObjCounter(this, --count);
1549 if (count == 0 && ui != null) {
1550 ui.installUI(this);
1551 }
1552 }
1553 }
1554
1555
1556 /**
1557 * Returns a string representation of this <code>JComboBox</code>.
1558 * This method is intended to be used only for debugging purposes,
1559 * and the content and format of the returned string may vary between
1560 * implementations. The returned string may be empty but may not
1561 * be <code>null</code>.
1562 *
1563 * @return a string representation of this <code>JComboBox</code>
1564 */
1565 protected String paramString() {
1566 String selectedItemReminderString = (selectedItemReminder != null ?
1567 selectedItemReminder.toString() :
1568 "");
1569 String isEditableString = (isEditable ? "true" : "false");
1570 String lightWeightPopupEnabledString = (lightWeightPopupEnabled ?
1571 "true" : "false");
1572
1573 return super.paramString() +
1574 ",isEditable=" + isEditableString +
1575 ",lightWeightPopupEnabled=" + lightWeightPopupEnabledString +
1576 ",maximumRowCount=" + maximumRowCount +
1577 ",selectedItemReminder=" + selectedItemReminderString;
1578 }
1579
1580
1581 ///////////////////
1582 // Accessibility support
1583 ///////////////////
1584
1585 /**
1586 * Gets the AccessibleContext associated with this JComboBox.
1587 * For combo boxes, the AccessibleContext takes the form of an
1588 * AccessibleJComboBox.
1589 * A new AccessibleJComboBox instance is created if necessary.
1590 *
1591 * @return an AccessibleJComboBox that serves as the
1592 * AccessibleContext of this JComboBox
1593 */
1594 public AccessibleContext getAccessibleContext() {
1595 if ( accessibleContext == null ) {
1596 accessibleContext = new AccessibleJComboBox();
1597 }
1598 return accessibleContext;
1599 }
1600
1601 /**
1602 * This class implements accessibility support for the
1603 * <code>JComboBox</code> class. It provides an implementation of the
1604 * Java Accessibility API appropriate to Combo Box user-interface elements.
1605 * <p>
1606 * <strong>Warning:</strong>
1607 * Serialized objects of this class will not be compatible with
1608 * future Swing releases. The current serialization support is
1609 * appropriate for short term storage or RMI between applications running
1610 * the same version of Swing. As of 1.4, support for long term storage
1611 * of all JavaBeans<sup><font size="-2">TM</font></sup>
1612 * has been added to the <code>java.beans</code> package.
1613 * Please see {@link java.beans.XMLEncoder}.
1614 */
1615 protected class AccessibleJComboBox extends AccessibleJComponent
1616 implements AccessibleAction, AccessibleSelection {
1617
1618
1619 private JList popupList; // combo box popup list
1620 private Accessible previousSelectedAccessible = null;
1621
1622 /**
1623 * Returns an AccessibleJComboBox instance
1624 * @since 1.4
1625 */
1626 public AccessibleJComboBox() {
1627 // set the combo box editor's accessible name and description
1628 JComboBox.this.addPropertyChangeListener(new AccessibleJComboBoxPropertyChangeListener());
1629 setEditorNameAndDescription();
1630
1631 // Get the popup list
1632 Accessible a = getUI().getAccessibleChild(JComboBox.this, 0);
1633 if (a instanceof javax.swing.plaf.basic.ComboPopup) {
1634 // Listen for changes to the popup menu selection.
1635 popupList = ((javax.swing.plaf.basic.ComboPopup)a).getList();
1636 popupList.addListSelectionListener(
1637 new AccessibleJComboBoxListSelectionListener());
1638 }
1639 // Listen for popup menu show/hide events
1640 JComboBox.this.addPopupMenuListener(
1641 new AccessibleJComboBoxPopupMenuListener());
1642 }
1643
1644 /*
1645 * JComboBox PropertyChangeListener
1646 */
1647 private class AccessibleJComboBoxPropertyChangeListener
1648 implements PropertyChangeListener {
1649
1650 public void propertyChange(PropertyChangeEvent e) {
1651 if (e.getPropertyName() == "editor") {
1652 // set the combo box editor's accessible name
1653 // and description
1654 setEditorNameAndDescription();
1655 }
1656 }
1657 }
1658
1659 /*
1660 * Sets the combo box editor's accessible name and descripton
1661 */
1662 private void setEditorNameAndDescription() {
1663 ComboBoxEditor editor = JComboBox.this.getEditor();
1664 if (editor != null) {
1665 Component comp = editor.getEditorComponent();
1666 if (comp instanceof Accessible) {
1667 AccessibleContext ac = comp.getAccessibleContext();
1668 if (ac != null) { // may be null
1669 ac.setAccessibleName(getAccessibleName());
1670 ac.setAccessibleDescription(getAccessibleDescription());
1671 }
1672 }
1673 }
1674 }
1675
1676 /*
1677 * Listener for combo box popup menu
1678 * TIGER - 4669379 4894434
1679 */
1680 private class AccessibleJComboBoxPopupMenuListener
1681 implements PopupMenuListener {
1682
1683 /**
1684 * This method is called before the popup menu becomes visible
1685 */
1686 public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
1687 // save the initial selection
1688 if (popupList == null) {
1689 return;
1690 }
1691 int selectedIndex = popupList.getSelectedIndex();
1692 if (selectedIndex < 0) {
1693 return;
1694 }
1695 previousSelectedAccessible =
1696 popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
1697 }
1698
1699 /**
1700 * This method is called before the popup menu becomes invisible
1701 * Note that a JPopupMenu can become invisible any time
1702 */
1703 public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
1704 // ignore
1705 }
1706
1707 /**
1708 * This method is called when the popup menu is canceled
1709 */
1710 public void popupMenuCanceled(PopupMenuEvent e) {
1711 // ignore
1712 }
1713 }
1714
1715 /*
1716 * Handles changes to the popup list selection.
1717 * TIGER - 4669379 4894434 4933143
1718 */
1719 private class AccessibleJComboBoxListSelectionListener
1720 implements ListSelectionListener {
1721
1722 public void valueChanged(ListSelectionEvent e) {
1723 if (popupList == null) {
1724 return;
1725 }
1726
1727 // Get the selected popup list item.
1728 int selectedIndex = popupList.getSelectedIndex();
1729 if (selectedIndex < 0) {
1730 return;
1731 }
1732 Accessible selectedAccessible =
1733 popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
1734 if (selectedAccessible == null) {
1735 return;
1736 }
1737
1738 // Fire a FOCUSED lost PropertyChangeEvent for the
1739 // previously selected list item.
1740 PropertyChangeEvent pce;
1741
1742 if (previousSelectedAccessible != null) {
1743 pce = new PropertyChangeEvent(previousSelectedAccessible,
1744 AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1745 AccessibleState.FOCUSED, null);
1746 firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1747 null, pce);
1748 }
1749 // Fire a FOCUSED gained PropertyChangeEvent for the
1750 // currently selected list item.
1751 pce = new PropertyChangeEvent(selectedAccessible,
1752 AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1753 null, AccessibleState.FOCUSED);
1754 firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1755 null, pce);
1756
1757 // Fire the ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY event
1758 // for the combo box.
1759 firePropertyChange(AccessibleContext.ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY,
1760 previousSelectedAccessible, selectedAccessible);
1761
1762 // Save the previous selection.
1763 previousSelectedAccessible = selectedAccessible;
1764 }
1765 }
1766
1767
1768 /**
1769 * Returns the number of accessible children in the object. If all
1770 * of the children of this object implement Accessible, than this
1771 * method should return the number of children of this object.
1772 *
1773 * @return the number of accessible children in the object.
1774 */
1775 public int getAccessibleChildrenCount() {
1776 // Always delegate to the UI if it exists
1777 if (ui != null) {
1778 return ui.getAccessibleChildrenCount(JComboBox.this);
1779 } else {
1780 return super.getAccessibleChildrenCount();
1781 }
1782 }
1783
1784 /**
1785 * Returns the nth Accessible child of the object.
1786 * The child at index zero represents the popup.
1787 * If the combo box is editable, the child at index one
1788 * represents the editor.
1789 *
1790 * @param i zero-based index of child
1791 * @return the nth Accessible child of the object
1792 */
1793 public Accessible getAccessibleChild(int i) {
1794 // Always delegate to the UI if it exists
1795 if (ui != null) {
1796 return ui.getAccessibleChild(JComboBox.this, i);
1797 } else {
1798 return super.getAccessibleChild(i);
1799 }
1800 }
1801
1802 /**
1803 * Get the role of this object.
1804 *
1805 * @return an instance of AccessibleRole describing the role of the
1806 * object
1807 * @see AccessibleRole
1808 */
1809 public AccessibleRole getAccessibleRole() {
1810 return AccessibleRole.COMBO_BOX;
1811 }
1812
1813 /**
1814 * Gets the state set of this object. The AccessibleStateSet of
1815 * an object is composed of a set of unique AccessibleStates.
1816 * A change in the AccessibleStateSet of an object will cause a
1817 * PropertyChangeEvent to be fired for the ACCESSIBLE_STATE_PROPERTY
1818 * property.
1819 *
1820 * @return an instance of AccessibleStateSet containing the
1821 * current state set of the object
1822 * @see AccessibleStateSet
1823 * @see AccessibleState
1824 * @see #addPropertyChangeListener
1825 *
1826 */
1827 public AccessibleStateSet getAccessibleStateSet() {
1828 // TIGER - 4489748
1829 AccessibleStateSet ass = super.getAccessibleStateSet();
1830 if (ass == null) {
1831 ass = new AccessibleStateSet();
1832 }
1833 if (JComboBox.this.isPopupVisible()) {
1834 ass.add(AccessibleState.EXPANDED);
1835 } else {
1836 ass.add(AccessibleState.COLLAPSED);
1837 }
1838 return ass;
1839 }
1840
1841 /**
1842 * Get the AccessibleAction associated with this object. In the
1843 * implementation of the Java Accessibility API for this class,
1844 * return this object, which is responsible for implementing the
1845 * AccessibleAction interface on behalf of itself.
1846 *
1847 * @return this object
1848 */
1849 public AccessibleAction getAccessibleAction() {
1850 return this;
1851 }
1852
1853 /**
1854 * Return a description of the specified action of the object.
1855 *
1856 * @param i zero-based index of the actions
1857 */
1858 public String getAccessibleActionDescription(int i) {
1859 if (i == 0) {
1860 return UIManager.getString("ComboBox.togglePopupText");
1861 }
1862 else {
1863 return null;
1864 }
1865 }
1866
1867 /**
1868 * Returns the number of Actions available in this object. The
1869 * default behavior of a combo box is to have one action.
1870 *
1871 * @return 1, the number of Actions in this object
1872 */
1873 public int getAccessibleActionCount() {
1874 return 1;
1875 }
1876
1877 /**
1878 * Perform the specified Action on the object
1879 *
1880 * @param i zero-based index of actions
1881 * @return true if the the action was performed; else false.
1882 */
1883 public boolean doAccessibleAction(int i) {
1884 if (i == 0) {
1885 setPopupVisible(!isPopupVisible());
1886 return true;
1887 }
1888 else {
1889 return false;
1890 }
1891 }
1892
1893
1894 /**
1895 * Get the AccessibleSelection associated with this object. In the
1896 * implementation of the Java Accessibility API for this class,
1897 * return this object, which is responsible for implementing the
1898 * AccessibleSelection interface on behalf of itself.
1899 *
1900 * @return this object
1901 */
1902 public AccessibleSelection getAccessibleSelection() {
1903 return this;
1904 }
1905
1906 /**
1907 * Returns the number of Accessible children currently selected.
1908 * If no children are selected, the return value will be 0.
1909 *
1910 * @return the number of items currently selected.
1911 * @since 1.3
1912 */
1913 public int getAccessibleSelectionCount() {
1914 Object o = JComboBox.this.getSelectedItem();
1915 if (o != null) {
1916 return 1;
1917 } else {
1918 return 0;
1919 }
1920 }
1921
1922 /**
1923 * Returns an Accessible representing the specified selected child
1924 * in the popup. If there isn't a selection, or there are
1925 * fewer children selected than the integer passed in, the return
1926 * value will be null.
1927 * <p>Note that the index represents the i-th selected child, which
1928 * is different from the i-th child.
1929 *
1930 * @param i the zero-based index of selected children
1931 * @return the i-th selected child
1932 * @see #getAccessibleSelectionCount
1933 * @since 1.3
1934 */
1935 public Accessible getAccessibleSelection(int i) {
1936 // Get the popup
1937 Accessible a =
1938 JComboBox.this.getUI().getAccessibleChild(JComboBox.this, 0);
1939 if (a != null &&
1940 a instanceof javax.swing.plaf.basic.ComboPopup) {
1941
1942 // get the popup list
1943 JList list = ((javax.swing.plaf.basic.ComboPopup)a).getList();
1944
1945 // return the i-th selection in the popup list
1946 AccessibleContext ac = list.getAccessibleContext();
1947 if (ac != null) {
1948 AccessibleSelection as = ac.getAccessibleSelection();
1949 if (as != null) {
1950 return as.getAccessibleSelection(i);
1951 }
1952 }
1953 }
1954 return null;
1955 }
1956
1957 /**
1958 * Determines if the current child of this object is selected.
1959 *
1960 * @return true if the current child of this object is selected;
1961 * else false
1962 * @param i the zero-based index of the child in this Accessible
1963 * object.
1964 * @see AccessibleContext#getAccessibleChild
1965 * @since 1.3
1966 */
1967 public boolean isAccessibleChildSelected(int i) {
1968 return JComboBox.this.getSelectedIndex() == i;
1969 }
1970
1971 /**
1972 * Adds the specified Accessible child of the object to the object's
1973 * selection. If the object supports multiple selections,
1974 * the specified child is added to any existing selection, otherwise
1975 * it replaces any existing selection in the object. If the
1976 * specified child is already selected, this method has no effect.
1977 *
1978 * @param i the zero-based index of the child
1979 * @see AccessibleContext#getAccessibleChild
1980 * @since 1.3
1981 */
1982 public void addAccessibleSelection(int i) {
1983 // TIGER - 4856195
1984 clearAccessibleSelection();
1985 JComboBox.this.setSelectedIndex(i);
1986 }
1987
1988 /**
1989 * Removes the specified child of the object from the object's
1990 * selection. If the specified item isn't currently selected, this
1991 * method has no effect.
1992 *
1993 * @param i the zero-based index of the child
1994 * @see AccessibleContext#getAccessibleChild
1995 * @since 1.3
1996 */
1997 public void removeAccessibleSelection(int i) {
1998 if (JComboBox.this.getSelectedIndex() == i) {
1999 clearAccessibleSelection();
2000 }
2001 }
2002
2003 /**
2004 * Clears the selection in the object, so that no children in the
2005 * object are selected.
2006 * @since 1.3
2007 */
2008 public void clearAccessibleSelection() {
2009 JComboBox.this.setSelectedIndex(-1);
2010 }
2011
2012 /**
2013 * Causes every child of the object to be selected
2014 * if the object supports multiple selections.
2015 * @since 1.3
2016 */
2017 public void selectAllAccessibleSelection() {
2018 // do nothing since multiple selection is not supported
2019 }
2020
2021 // public Accessible getAccessibleAt(Point p) {
2022 // Accessible a = getAccessibleChild(1);
2023 // if ( a != null ) {
2024 // return a; // the editor
2025 // }
2026 // else {
2027 // return getAccessibleChild(0); // the list
2028 // }
2029 // }
2030 private EditorAccessibleContext editorAccessibleContext = null;
2031
2032 private class AccessibleEditor implements Accessible {
2033 public AccessibleContext getAccessibleContext() {
2034 if (editorAccessibleContext == null) {
2035 Component c = JComboBox.this.getEditor().getEditorComponent();
2036 if (c instanceof Accessible) {
2037 editorAccessibleContext =
2038 new EditorAccessibleContext((Accessible)c);
2039 }
2040 }
2041 return editorAccessibleContext;
2042 }
2043 }
2044
2045 /*
2046 * Wrapper class for the AccessibleContext implemented by the
2047 * combo box editor. Delegates all method calls except
2048 * getAccessibleIndexInParent to the editor. The
2049 * getAccessibleIndexInParent method returns the selected
2050 * index in the combo box.
2051 */
2052 private class EditorAccessibleContext extends AccessibleContext {
2053
2054 private AccessibleContext ac;
2055
2056 private EditorAccessibleContext() {
2057 }
2058
2059 /*
2060 * @param a the AccessibleContext implemented by the
2061 * combo box editor
2062 */
2063 EditorAccessibleContext(Accessible a) {
2064 this.ac = a.getAccessibleContext();
2065 }
2066
2067 /**
2068 * Gets the accessibleName property of this object. The accessibleName
2069 * property of an object is a localized String that designates the purpose
2070 * of the object. For example, the accessibleName property of a label
2071 * or button might be the text of the label or button itself. In the
2072 * case of an object that doesn't display its name, the accessibleName
2073 * should still be set. For example, in the case of a text field used
2074 * to enter the name of a city, the accessibleName for the en_US locale
2075 * could be 'city.'
2076 *
2077 * @return the localized name of the object; null if this
2078 * object does not have a name
2079 *
2080 * @see #setAccessibleName
2081 */
2082 public String getAccessibleName() {
2083 return ac.getAccessibleName();
2084 }
2085
2086 /**
2087 * Sets the localized accessible name of this object. Changing the
2088 * name will cause a PropertyChangeEvent to be fired for the
2089 * ACCESSIBLE_NAME_PROPERTY property.
2090 *
2091 * @param s the new localized name of the object.
2092 *
2093 * @see #getAccessibleName
2094 * @see #addPropertyChangeListener
2095 *
2096 * @beaninfo
2097 * preferred: true
2098 * description: Sets the accessible name for the component.
2099 */
2100 public void setAccessibleName(String s) {
2101 ac.setAccessibleName(s);
2102 }
2103
2104 /**
2105 * Gets the accessibleDescription property of this object. The
2106 * accessibleDescription property of this object is a short localized
2107 * phrase describing the purpose of the object. For example, in the
2108 * case of a 'Cancel' button, the accessibleDescription could be
2109 * 'Ignore changes and close dialog box.'
2110 *
2111 * @return the localized description of the object; null if
2112 * this object does not have a description
2113 *
2114 * @see #setAccessibleDescription
2115 */
2116 public String getAccessibleDescription() {
2117 return ac.getAccessibleDescription();
2118 }
2119
2120 /**
2121 * Sets the accessible description of this object. Changing the
2122 * name will cause a PropertyChangeEvent to be fired for the
2123 * ACCESSIBLE_DESCRIPTION_PROPERTY property.
2124 *
2125 * @param s the new localized description of the object
2126 *
2127 * @see #setAccessibleName
2128 * @see #addPropertyChangeListener
2129 *
2130 * @beaninfo
2131 * preferred: true
2132 * description: Sets the accessible description for the component.
2133 */
2134 public void setAccessibleDescription(String s) {
2135 ac.setAccessibleDescription(s);
2136 }
2137
2138 /**
2139 * Gets the role of this object. The role of the object is the generic
2140 * purpose or use of the class of this object. For example, the role
2141 * of a push button is AccessibleRole.PUSH_BUTTON. The roles in
2142 * AccessibleRole are provided so component developers can pick from
2143 * a set of predefined roles. This enables assistive technologies to
2144 * provide a consistent interface to various tweaked subclasses of
2145 * components (e.g., use AccessibleRole.PUSH_BUTTON for all components
2146 * that act like a push button) as well as distinguish between sublasses
2147 * that behave differently (e.g., AccessibleRole.CHECK_BOX for check boxes
2148 * and AccessibleRole.RADIO_BUTTON for radio buttons).
2149 * <p>Note that the AccessibleRole class is also extensible, so
2150 * custom component developers can define their own AccessibleRole's
2151 * if the set of predefined roles is inadequate.
2152 *
2153 * @return an instance of AccessibleRole describing the role of the object
2154 * @see AccessibleRole
2155 */
2156 public AccessibleRole getAccessibleRole() {
2157 return ac.getAccessibleRole();
2158 }
2159
2160 /**
2161 * Gets the state set of this object. The AccessibleStateSet of an object
2162 * is composed of a set of unique AccessibleStates. A change in the
2163 * AccessibleStateSet of an object will cause a PropertyChangeEvent to
2164 * be fired for the ACCESSIBLE_STATE_PROPERTY property.
2165 *
2166 * @return an instance of AccessibleStateSet containing the
2167 * current state set of the object
2168 * @see AccessibleStateSet
2169 * @see AccessibleState
2170 * @see #addPropertyChangeListener
2171 */
2172 public AccessibleStateSet getAccessibleStateSet() {
2173 return ac.getAccessibleStateSet();
2174 }
2175
2176 /**
2177 * Gets the Accessible parent of this object.
2178 *
2179 * @return the Accessible parent of this object; null if this
2180 * object does not have an Accessible parent
2181 */
2182 public Accessible getAccessibleParent() {
2183 return ac.getAccessibleParent();
2184 }
2185
2186 /**
2187 * Sets the Accessible parent of this object. This is meant to be used
2188 * only in the situations where the actual component's parent should
2189 * not be treated as the component's accessible parent and is a method
2190 * that should only be called by the parent of the accessible child.
2191 *
2192 * @param a - Accessible to be set as the parent
2193 */
2194 public void setAccessibleParent(Accessible a) {
2195 ac.setAccessibleParent(a);
2196 }
2197
2198 /**
2199 * Gets the 0-based index of this object in its accessible parent.
2200 *
2201 * @return the 0-based index of this object in its parent; -1 if this
2202 * object does not have an accessible parent.
2203 *
2204 * @see #getAccessibleParent
2205 * @see #getAccessibleChildrenCount
2206 * @see #getAccessibleChild
2207 */
2208 public int getAccessibleIndexInParent() {
2209 return JComboBox.this.getSelectedIndex();
2210 }
2211
2212 /**
2213 * Returns the number of accessible children of the object.
2214 *
2215 * @return the number of accessible children of the object.
2216 */
2217 public int getAccessibleChildrenCount() {
2218 return ac.getAccessibleChildrenCount();
2219 }
2220
2221 /**
2222 * Returns the specified Accessible child of the object. The Accessible
2223 * children of an Accessible object are zero-based, so the first child
2224 * of an Accessible child is at index 0, the second child is at index 1,
2225 * and so on.
2226 *
2227 * @param i zero-based index of child
2228 * @return the Accessible child of the object
2229 * @see #getAccessibleChildrenCount
2230 */
2231 public Accessible getAccessibleChild(int i) {
2232 return ac.getAccessibleChild(i);
2233 }
2234
2235 /**
2236 * Gets the locale of the component. If the component does not have a
2237 * locale, then the locale of its parent is returned.
2238 *
2239 * @return this component's locale. If this component does not have
2240 * a locale, the locale of its parent is returned.
2241 *
2242 * @exception IllegalComponentStateException
2243 * If the Component does not have its own locale and has not yet been
2244 * added to a containment hierarchy such that the locale can be
2245 * determined from the containing parent.
2246 */
2247 public Locale getLocale() throws IllegalComponentStateException {
2248 return ac.getLocale();
2249 }
2250
2251 /**
2252 * Adds a PropertyChangeListener to the listener list.
2253 * The listener is registered for all Accessible properties and will
2254 * be called when those properties change.
2255 *
2256 * @see #ACCESSIBLE_NAME_PROPERTY
2257 * @see #ACCESSIBLE_DESCRIPTION_PROPERTY
2258 * @see #ACCESSIBLE_STATE_PROPERTY
2259 * @see #ACCESSIBLE_VALUE_PROPERTY
2260 * @see #ACCESSIBLE_SELECTION_PROPERTY
2261 * @see #ACCESSIBLE_TEXT_PROPERTY
2262 * @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
2263 *
2264 * @param listener The PropertyChangeListener to be added
2265 */
2266 public void addPropertyChangeListener(PropertyChangeListener listener) {
2267 ac.addPropertyChangeListener(listener);
2268 }
2269
2270 /**
2271 * Removes a PropertyChangeListener from the listener list.
2272 * This removes a PropertyChangeListener that was registered
2273 * for all properties.
2274 *
2275 * @param listener The PropertyChangeListener to be removed
2276 */
2277 public void removePropertyChangeListener(PropertyChangeListener listener) {
2278 ac.removePropertyChangeListener(listener);
2279 }
2280
2281 /**
2282 * Gets the AccessibleAction associated with this object that supports
2283 * one or more actions.
2284 *
2285 * @return AccessibleAction if supported by object; else return null
2286 * @see AccessibleAction
2287 */
2288 public AccessibleAction getAccessibleAction() {
2289 return ac.getAccessibleAction();
2290 }
2291
2292 /**
2293 * Gets the AccessibleComponent associated with this object that has a
2294 * graphical representation.
2295 *
2296 * @return AccessibleComponent if supported by object; else return null
2297 * @see AccessibleComponent
2298 */
2299 public AccessibleComponent getAccessibleComponent() {
2300 return ac.getAccessibleComponent();
2301 }
2302
2303 /**
2304 * Gets the AccessibleSelection associated with this object which allows its
2305 * Accessible children to be selected.
2306 *
2307 * @return AccessibleSelection if supported by object; else return null
2308 * @see AccessibleSelection
2309 */
2310 public AccessibleSelection getAccessibleSelection() {
2311 return ac.getAccessibleSelection();
2312 }
2313
2314 /**
2315 * Gets the AccessibleText associated with this object presenting
2316 * text on the display.
2317 *
2318 * @return AccessibleText if supported by object; else return null
2319 * @see AccessibleText
2320 */
2321 public AccessibleText getAccessibleText() {
2322 return ac.getAccessibleText();
2323 }
2324
2325 /**
2326 * Gets the AccessibleEditableText associated with this object
2327 * presenting editable text on the display.
2328 *
2329 * @return AccessibleEditableText if supported by object; else return null
2330 * @see AccessibleEditableText
2331 */
2332 public AccessibleEditableText getAccessibleEditableText() {
2333 return ac.getAccessibleEditableText();
2334 }
2335
2336 /**
2337 * Gets the AccessibleValue associated with this object that supports a
2338 * Numerical value.
2339 *
2340 * @return AccessibleValue if supported by object; else return null
2341 * @see AccessibleValue
2342 */
2343 public AccessibleValue getAccessibleValue() {
2344 return ac.getAccessibleValue();
2345 }
2346
2347 /**
2348 * Gets the AccessibleIcons associated with an object that has
2349 * one or more associated icons
2350 *
2351 * @return an array of AccessibleIcon if supported by object;
2352 * otherwise return null
2353 * @see AccessibleIcon
2354 */
2355 public AccessibleIcon [] getAccessibleIcon() {
2356 return ac.getAccessibleIcon();
2357 }
2358
2359 /**
2360 * Gets the AccessibleRelationSet associated with an object
2361 *
2362 * @return an AccessibleRelationSet if supported by object;
2363 * otherwise return null
2364 * @see AccessibleRelationSet
2365 */
2366 public AccessibleRelationSet getAccessibleRelationSet() {
2367 return ac.getAccessibleRelationSet();
2368 }
2369
2370 /**
2371 * Gets the AccessibleTable associated with an object
2372 *
2373 * @return an AccessibleTable if supported by object;
2374 * otherwise return null
2375 * @see AccessibleTable
2376 */
2377 public AccessibleTable getAccessibleTable() {
2378 return ac.getAccessibleTable();
2379 }
2380
2381 /**
2382 * Support for reporting bound property changes. If oldValue and
2383 * newValue are not equal and the PropertyChangeEvent listener list
2384 * is not empty, then fire a PropertyChange event to each listener.
2385 * In general, this is for use by the Accessible objects themselves
2386 * and should not be called by an application program.
2387 * @param propertyName The programmatic name of the property that
2388 * was changed.
2389 * @param oldValue The old value of the property.
2390 * @param newValue The new value of the property.
2391 * @see java.beans.PropertyChangeSupport
2392 * @see #addPropertyChangeListener
2393 * @see #removePropertyChangeListener
2394 * @see #ACCESSIBLE_NAME_PROPERTY
2395 * @see #ACCESSIBLE_DESCRIPTION_PROPERTY
2396 * @see #ACCESSIBLE_STATE_PROPERTY
2397 * @see #ACCESSIBLE_VALUE_PROPERTY
2398 * @see #ACCESSIBLE_SELECTION_PROPERTY
2399 * @see #ACCESSIBLE_TEXT_PROPERTY
2400 * @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
2401 */
2402 public void firePropertyChange(String propertyName,
2403 Object oldValue,
2404 Object newValue) {
2405 ac.firePropertyChange(propertyName, oldValue, newValue);
2406 }
2407 }
2408
2409 } // innerclass AccessibleJComboBox
2410 }