1 /*
2 * Copyright (c) 1997, 2014, 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™
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 *
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 @SuppressWarnings("serial") // Same-version serialization only
82 public class JComboBox<E> extends JComponent
83 implements ItemSelectable,ListDataListener,ActionListener, Accessible {
84 /**
85 * @see #getUIClassID
86 * @see #readObject
87 */
88 private static final String uiClassID = "ComboBoxUI";
89
90 /**
91 * This protected field is implementation specific. Do not access directly
92 * or override. Use the accessor methods instead.
93 *
94 * @see #getModel
95 * @see #setModel
96 */
97 protected ComboBoxModel<E> dataModel;
98 /**
99 * This protected field is implementation specific. Do not access directly
100 * or override. Use the accessor methods instead.
101 *
102 * @see #getRenderer
103 * @see #setRenderer
104 */
105 protected ListCellRenderer<? super E> renderer;
106 /**
107 * This protected field is implementation specific. Do not access directly
108 * or override. Use the accessor methods instead.
109 *
110 * @see #getEditor
111 * @see #setEditor
112 */
113 protected ComboBoxEditor editor;
114 /**
115 * This protected field is implementation specific. Do not access directly
116 * or override. Use the accessor methods instead.
117 *
118 * @see #getMaximumRowCount
119 * @see #setMaximumRowCount
120 */
121 protected int maximumRowCount = 8;
122
123 /**
124 * This protected field is implementation specific. Do not access directly
125 * or override. Use the accessor methods instead.
126 *
127 * @see #isEditable
128 * @see #setEditable
129 */
130 protected boolean isEditable = false;
131 /**
132 * This protected field is implementation specific. Do not access directly
133 * or override. Use the accessor methods instead.
134 *
135 * @see #setKeySelectionManager
136 * @see #getKeySelectionManager
137 */
138 protected KeySelectionManager keySelectionManager = null;
139 /**
140 * This protected field is implementation specific. Do not access directly
141 * or override. Use the accessor methods instead.
142 *
143 * @see #setActionCommand
144 * @see #getActionCommand
145 */
146 protected String actionCommand = "comboBoxChanged";
147 /**
148 * This protected field is implementation specific. Do not access directly
149 * or override. Use the accessor methods instead.
150 *
151 * @see #setLightWeightPopupEnabled
152 * @see #isLightWeightPopupEnabled
153 */
154 protected boolean lightWeightPopupEnabled = JPopupMenu.getDefaultLightWeightPopupEnabled();
155
156 /**
157 * This protected field is implementation specific. Do not access directly
158 * or override.
159 */
160 protected Object selectedItemReminder = null;
161
162 private E prototypeDisplayValue;
163
164 // Flag to ensure that infinite loops do not occur with ActionEvents.
165 private boolean firingActionEvent = false;
166
167 // Flag to ensure the we don't get multiple ActionEvents on item selection.
168 private boolean selectingItem = false;
169
170 /**
171 * Creates a <code>JComboBox</code> that takes its items from an
172 * existing <code>ComboBoxModel</code>. Since the
173 * <code>ComboBoxModel</code> is provided, a combo box created using
174 * this constructor does not create a default combo box model and
175 * may impact how the insert, remove and add methods behave.
176 *
177 * @param aModel the <code>ComboBoxModel</code> that provides the
178 * displayed list of items
179 * @see DefaultComboBoxModel
180 */
181 public JComboBox(ComboBoxModel<E> aModel) {
182 super();
183 setModel(aModel);
184 init();
185 }
186
187 /**
188 * Creates a <code>JComboBox</code> that contains the elements
189 * in the specified array. By default the first item in the array
190 * (and therefore the data model) becomes selected.
191 *
192 * @param items an array of objects to insert into the combo box
193 * @see DefaultComboBoxModel
194 */
195 public JComboBox(E[] items) {
196 super();
197 setModel(new DefaultComboBoxModel<E>(items));
198 init();
199 }
200
201 /**
202 * Creates a <code>JComboBox</code> that contains the elements
203 * in the specified Vector. By default the first item in the vector
204 * (and therefore the data model) becomes selected.
205 *
206 * @param items an array of vectors to insert into the combo box
207 * @see DefaultComboBoxModel
208 */
209 public JComboBox(Vector<E> items) {
210 super();
211 setModel(new DefaultComboBoxModel<E>(items));
212 init();
213 }
214
215 /**
216 * Creates a <code>JComboBox</code> with a default data model.
217 * The default data model is an empty list of objects.
218 * Use <code>addItem</code> to add items. By default the first item
219 * in the data model becomes selected.
220 *
221 * @see DefaultComboBoxModel
222 */
223 public JComboBox() {
224 super();
225 setModel(new DefaultComboBoxModel<E>());
226 init();
227 }
228
229 private void init() {
230 installAncestorListener();
231 setUIProperty("opaque",true);
232 updateUI();
233 }
234
235 protected void installAncestorListener() {
236 addAncestorListener(new AncestorListener(){
237 public void ancestorAdded(AncestorEvent event){ hidePopup();}
238 public void ancestorRemoved(AncestorEvent event){ hidePopup();}
239 public void ancestorMoved(AncestorEvent event){
240 if (event.getSource() != JComboBox.this)
241 hidePopup();
242 }});
243 }
244
245 /**
246 * Sets the L&F object that renders this component.
247 *
248 * @param ui the <code>ComboBoxUI</code> L&F object
249 * @see UIDefaults#getUI
250 *
251 * @beaninfo
252 * bound: true
253 * hidden: true
254 * attribute: visualUpdate true
255 * description: The UI object that implements the Component's LookAndFeel.
256 */
257 public void setUI(ComboBoxUI ui) {
258 super.setUI(ui);
259 }
260
261 /**
262 * Resets the UI property to a value from the current look and feel.
263 *
264 * @see JComponent#updateUI
265 */
266 public void updateUI() {
267 setUI((ComboBoxUI)UIManager.getUI(this));
268
269 ListCellRenderer<? super E> renderer = getRenderer();
270 if (renderer instanceof Component) {
271 SwingUtilities.updateComponentTreeUI((Component)renderer);
272 }
273 }
274
275
276 /**
277 * Returns the name of the L&F class that renders this component.
278 *
279 * @return the string "ComboBoxUI"
280 * @see JComponent#getUIClassID
281 * @see UIDefaults#getUI
282 */
283 public String getUIClassID() {
284 return uiClassID;
285 }
286
287
288 /**
289 * Returns the L&F object that renders this component.
290 *
291 * @return the ComboBoxUI object that renders this component
292 */
293 public ComboBoxUI getUI() {
294 return(ComboBoxUI)ui;
295 }
296
297 /**
298 * Sets the data model that the <code>JComboBox</code> uses to obtain
299 * the list of items.
300 *
301 * @param aModel the <code>ComboBoxModel</code> that provides the
302 * displayed list of items
303 *
304 * @beaninfo
305 * bound: true
306 * description: Model that the combo box uses to get data to display.
307 */
308 public void setModel(ComboBoxModel<E> aModel) {
309 ComboBoxModel<E> oldModel = dataModel;
310 if (oldModel != null) {
311 oldModel.removeListDataListener(this);
312 }
313 dataModel = aModel;
314 dataModel.addListDataListener(this);
315
316 // set the current selected item.
317 selectedItemReminder = dataModel.getSelectedItem();
318
319 firePropertyChange( "model", oldModel, dataModel);
320 }
321
322 /**
323 * Returns the data model currently used by the <code>JComboBox</code>.
324 *
325 * @return the <code>ComboBoxModel</code> that provides the displayed
326 * list of items
327 */
328 public ComboBoxModel<E> getModel() {
329 return dataModel;
330 }
331
332 /*
333 * Properties
334 */
335
336 /**
337 * Sets the <code>lightWeightPopupEnabled</code> property, which
338 * provides a hint as to whether or not a lightweight
339 * <code>Component</code> should be used to contain the
340 * <code>JComboBox</code>, versus a heavyweight
341 * <code>Component</code> such as a <code>Panel</code>
342 * or a <code>Window</code>. The decision of lightweight
343 * versus heavyweight is ultimately up to the
344 * <code>JComboBox</code>. Lightweight windows are more
345 * efficient than heavyweight windows, but lightweight
346 * and heavyweight components do not mix well in a GUI.
347 * If your application mixes lightweight and heavyweight
348 * components, you should disable lightweight popups.
349 * The default value for the <code>lightWeightPopupEnabled</code>
350 * property is <code>true</code>, unless otherwise specified
351 * by the look and feel. Some look and feels always use
352 * heavyweight popups, no matter what the value of this property.
353 * <p>
354 * See the article <a href="http://www.oracle.com/technetwork/articles/java/mixing-components-433992.html">Mixing Heavy and Light Components</a>
355 * This method fires a property changed event.
356 *
357 * @param aFlag if <code>true</code>, lightweight popups are desired
358 *
359 * @beaninfo
360 * bound: true
361 * expert: true
362 * description: Set to <code>false</code> to require heavyweight popups.
363 */
364 public void setLightWeightPopupEnabled(boolean aFlag) {
365 boolean oldFlag = lightWeightPopupEnabled;
366 lightWeightPopupEnabled = aFlag;
367 firePropertyChange("lightWeightPopupEnabled", oldFlag, lightWeightPopupEnabled);
368 }
369
370 /**
371 * Gets the value of the <code>lightWeightPopupEnabled</code>
372 * property.
373 *
374 * @return the value of the <code>lightWeightPopupEnabled</code>
375 * property
376 * @see #setLightWeightPopupEnabled
377 */
378 public boolean isLightWeightPopupEnabled() {
379 return lightWeightPopupEnabled;
380 }
381
382 /**
383 * Determines whether the <code>JComboBox</code> field is editable.
384 * An editable <code>JComboBox</code> allows the user to type into the
385 * field or selected an item from the list to initialize the field,
386 * after which it can be edited. (The editing affects only the field,
387 * the list item remains intact.) A non editable <code>JComboBox</code>
388 * displays the selected item in the field,
389 * but the selection cannot be modified.
390 *
391 * @param aFlag a boolean value, where true indicates that the
392 * field is editable
393 *
394 * @beaninfo
395 * bound: true
396 * preferred: true
397 * description: If true, the user can type a new value in the combo box.
398 */
399 public void setEditable(boolean aFlag) {
400 boolean oldFlag = isEditable;
401 isEditable = aFlag;
402 firePropertyChange( "editable", oldFlag, isEditable );
403 }
404
405 /**
406 * Returns true if the <code>JComboBox</code> is editable.
407 * By default, a combo box is not editable.
408 *
409 * @return true if the <code>JComboBox</code> is editable, else false
410 */
411 public boolean isEditable() {
412 return isEditable;
413 }
414
415 /**
416 * Sets the maximum number of rows the <code>JComboBox</code> displays.
417 * If the number of objects in the model is greater than count,
418 * the combo box uses a scrollbar.
419 *
420 * @param count an integer specifying the maximum number of items to
421 * display in the list before using a scrollbar
422 * @beaninfo
423 * bound: true
424 * preferred: true
425 * description: The maximum number of rows the popup should have
426 */
427 public void setMaximumRowCount(int count) {
428 int oldCount = maximumRowCount;
429 maximumRowCount = count;
430 firePropertyChange( "maximumRowCount", oldCount, maximumRowCount );
431 }
432
433 /**
434 * Returns the maximum number of items the combo box can display
435 * without a scrollbar
436 *
437 * @return an integer specifying the maximum number of items that are
438 * displayed in the list before using a scrollbar
439 */
440 public int getMaximumRowCount() {
441 return maximumRowCount;
442 }
443
444 /**
445 * Sets the renderer that paints the list items and the item selected from the list in
446 * the JComboBox field. The renderer is used if the JComboBox is not
447 * editable. If it is editable, the editor is used to render and edit
448 * the selected item.
449 * <p>
450 * The default renderer displays a string or an icon.
451 * Other renderers can handle graphic images and composite items.
452 * <p>
453 * To display the selected item,
454 * <code>aRenderer.getListCellRendererComponent</code>
455 * is called, passing the list object and an index of -1.
456 *
457 * @param aRenderer the <code>ListCellRenderer</code> that
458 * displays the selected item
459 * @see #setEditor
460 * @beaninfo
461 * bound: true
462 * expert: true
463 * description: The renderer that paints the item selected in the list.
464 */
465 public void setRenderer(ListCellRenderer<? super E> aRenderer) {
466 ListCellRenderer<? super E> oldRenderer = renderer;
467 renderer = aRenderer;
468 firePropertyChange( "renderer", oldRenderer, renderer );
469 invalidate();
470 }
471
472 /**
473 * Returns the renderer used to display the selected item in the
474 * <code>JComboBox</code> field.
475 *
476 * @return the <code>ListCellRenderer</code> that displays
477 * the selected item.
478 */
479 public ListCellRenderer<? super E> getRenderer() {
480 return renderer;
481 }
482
483 /**
484 * Sets the editor used to paint and edit the selected item in the
485 * <code>JComboBox</code> field. The editor is used only if the
486 * receiving <code>JComboBox</code> is editable. If not editable,
487 * the combo box uses the renderer to paint the selected item.
488 *
489 * @param anEditor the <code>ComboBoxEditor</code> that
490 * displays the selected item
491 * @see #setRenderer
492 * @beaninfo
493 * bound: true
494 * expert: true
495 * description: The editor that combo box uses to edit the current value
496 */
497 public void setEditor(ComboBoxEditor anEditor) {
498 ComboBoxEditor oldEditor = editor;
499
500 if ( editor != null ) {
501 editor.removeActionListener(this);
502 }
503 editor = anEditor;
504 if ( editor != null ) {
505 editor.addActionListener(this);
506 }
507 firePropertyChange( "editor", oldEditor, editor );
508 }
509
510 /**
511 * Returns the editor used to paint and edit the selected item in the
512 * <code>JComboBox</code> field.
513 *
514 * @return the <code>ComboBoxEditor</code> that displays the selected item
515 */
516 public ComboBoxEditor getEditor() {
517 return editor;
518 }
519
520 //
521 // Selection
522 //
523
524 /**
525 * Sets the selected item in the combo box display area to the object in
526 * the argument.
527 * If <code>anObject</code> is in the list, the display area shows
528 * <code>anObject</code> selected.
529 * <p>
530 * If <code>anObject</code> is <i>not</i> in the list and the combo box is
531 * uneditable, it will not change the current selection. For editable
532 * combo boxes, the selection will change to <code>anObject</code>.
533 * <p>
534 * If this constitutes a change in the selected item,
535 * <code>ItemListener</code>s added to the combo box will be notified with
536 * one or two <code>ItemEvent</code>s.
537 * If there is a current selected item, an <code>ItemEvent</code> will be
538 * fired and the state change will be <code>ItemEvent.DESELECTED</code>.
539 * If <code>anObject</code> is in the list and is not currently selected
540 * then an <code>ItemEvent</code> will be fired and the state change will
541 * be <code>ItemEvent.SELECTED</code>.
542 * <p>
543 * <code>ActionListener</code>s added to the combo box will be notified
544 * with an <code>ActionEvent</code> when this method is called.
545 *
546 * @param anObject the list object to select; use <code>null</code> to
547 clear the selection
548 * @beaninfo
549 * preferred: true
550 * description: Sets the selected item in the JComboBox.
551 */
552 public void setSelectedItem(Object anObject) {
553 Object oldSelection = selectedItemReminder;
554 Object objectToSelect = anObject;
555 if (oldSelection == null || !oldSelection.equals(anObject)) {
556
557 if (anObject != null && !isEditable()) {
558 // For non editable combo boxes, an invalid selection
559 // will be rejected.
560 boolean found = false;
561 for (int i = 0; i < dataModel.getSize(); i++) {
562 E element = dataModel.getElementAt(i);
563 if (anObject.equals(element)) {
564 found = true;
565 objectToSelect = element;
566 break;
567 }
568 }
569 if (!found) {
570 return;
571 }
572 }
573
574 // Must toggle the state of this flag since this method
575 // call may result in ListDataEvents being fired.
576 selectingItem = true;
577 dataModel.setSelectedItem(objectToSelect);
578 selectingItem = false;
579
580 if (selectedItemReminder != dataModel.getSelectedItem()) {
581 // in case a users implementation of ComboBoxModel
582 // doesn't fire a ListDataEvent when the selection
583 // changes.
584 selectedItemChanged();
585 }
586 }
587 fireActionEvent();
588 }
589
590 /**
591 * Returns the current selected item.
592 * <p>
593 * If the combo box is editable, then this value may not have been added
594 * to the combo box with <code>addItem</code>, <code>insertItemAt</code>
595 * or the data constructors.
596 *
597 * @return the current selected Object
598 * @see #setSelectedItem
599 */
600 public Object getSelectedItem() {
601 return dataModel.getSelectedItem();
602 }
603
604 /**
605 * Selects the item at index <code>anIndex</code>.
606 *
607 * @param anIndex an integer specifying the list item to select,
608 * where 0 specifies the first item in the list and -1 indicates no selection
609 * @exception IllegalArgumentException if <code>anIndex</code> < -1 or
610 * <code>anIndex</code> is greater than or equal to size
611 * @beaninfo
612 * preferred: true
613 * description: The item at index is selected.
614 */
615 public void setSelectedIndex(int anIndex) {
616 int size = dataModel.getSize();
617
618 if ( anIndex == -1 ) {
619 setSelectedItem( null );
620 } else if ( anIndex < -1 || anIndex >= size ) {
621 throw new IllegalArgumentException("setSelectedIndex: " + anIndex + " out of bounds");
622 } else {
623 setSelectedItem(dataModel.getElementAt(anIndex));
624 }
625 }
626
627 /**
628 * Returns the first item in the list that matches the given item.
629 * The result is not always defined if the <code>JComboBox</code>
630 * allows selected items that are not in the list.
631 * Returns -1 if there is no selected item or if the user specified
632 * an item which is not in the list.
633
634 * @return an integer specifying the currently selected list item,
635 * where 0 specifies
636 * the first item in the list;
637 * or -1 if no item is selected or if
638 * the currently selected item is not in the list
639 */
640 @Transient
641 public int getSelectedIndex() {
642 Object sObject = dataModel.getSelectedItem();
643 int i,c;
644 E obj;
645
646 for ( i=0,c=dataModel.getSize();i<c;i++ ) {
647 obj = dataModel.getElementAt(i);
648 if ( obj != null && obj.equals(sObject) )
649 return i;
650 }
651 return -1;
652 }
653
654 /**
655 * Returns the "prototypical display" value - an Object used
656 * for the calculation of the display height and width.
657 *
658 * @return the value of the <code>prototypeDisplayValue</code> property
659 * @see #setPrototypeDisplayValue
660 * @since 1.4
661 */
662 public E getPrototypeDisplayValue() {
663 return prototypeDisplayValue;
664 }
665
666 /**
667 * Sets the prototype display value used to calculate the size of the display
668 * for the UI portion.
669 * <p>
670 * If a prototype display value is specified, the preferred size of
671 * the combo box is calculated by configuring the renderer with the
672 * prototype display value and obtaining its preferred size. Specifying
673 * the preferred display value is often useful when the combo box will be
674 * displaying large amounts of data. If no prototype display value has
675 * been specified, the renderer must be configured for each value from
676 * the model and its preferred size obtained, which can be
677 * relatively expensive.
678 *
679 * @param prototypeDisplayValue the prototype display value
680 * @see #getPrototypeDisplayValue
681 * @since 1.4
682 * @beaninfo
683 * bound: true
684 * attribute: visualUpdate true
685 * description: The display prototype value, used to compute display width and height.
686 */
687 public void setPrototypeDisplayValue(E prototypeDisplayValue) {
688 Object oldValue = this.prototypeDisplayValue;
689 this.prototypeDisplayValue = prototypeDisplayValue;
690 firePropertyChange("prototypeDisplayValue", oldValue, prototypeDisplayValue);
691 }
692
693 /**
694 * Adds an item to the item list.
695 * This method works only if the <code>JComboBox</code> uses a
696 * mutable data model.
697 * <p>
698 * <strong>Warning:</strong>
699 * Focus and keyboard navigation problems may arise if you add duplicate
700 * String objects. A workaround is to add new objects instead of String
701 * objects and make sure that the toString() method is defined.
702 * For example:
703 * <pre>
704 * comboBox.addItem(makeObj("Item 1"));
705 * comboBox.addItem(makeObj("Item 1"));
706 * ...
707 * private Object makeObj(final String item) {
708 * return new Object() { public String toString() { return item; } };
709 * }
710 * </pre>
711 *
712 * @param item the item to add to the list
713 * @see MutableComboBoxModel
714 */
715 public void addItem(E item) {
716 checkMutableComboBoxModel();
717 ((MutableComboBoxModel<E>)dataModel).addElement(item);
718 }
719
720 /**
721 * Inserts an item into the item list at a given index.
722 * This method works only if the <code>JComboBox</code> uses a
723 * mutable data model.
724 *
725 * @param item the item to add to the list
726 * @param index an integer specifying the position at which
727 * to add the item
728 * @see MutableComboBoxModel
729 */
730 public void insertItemAt(E item, int index) {
731 checkMutableComboBoxModel();
732 ((MutableComboBoxModel<E>)dataModel).insertElementAt(item,index);
733 }
734
735 /**
736 * Removes an item from the item list.
737 * This method works only if the <code>JComboBox</code> uses a
738 * mutable data model.
739 *
740 * @param anObject the object to remove from the item list
741 * @see MutableComboBoxModel
742 */
743 public void removeItem(Object anObject) {
744 checkMutableComboBoxModel();
745 ((MutableComboBoxModel)dataModel).removeElement(anObject);
746 }
747
748 /**
749 * Removes the item at <code>anIndex</code>
750 * This method works only if the <code>JComboBox</code> uses a
751 * mutable data model.
752 *
753 * @param anIndex an int specifying the index of the item to remove,
754 * where 0
755 * indicates the first item in the list
756 * @see MutableComboBoxModel
757 */
758 public void removeItemAt(int anIndex) {
759 checkMutableComboBoxModel();
760 ((MutableComboBoxModel<E>)dataModel).removeElementAt( anIndex );
761 }
762
763 /**
764 * Removes all items from the item list.
765 */
766 public void removeAllItems() {
767 checkMutableComboBoxModel();
768 MutableComboBoxModel<E> model = (MutableComboBoxModel<E>)dataModel;
769 int size = model.getSize();
770
771 if ( model instanceof DefaultComboBoxModel ) {
772 ((DefaultComboBoxModel)model).removeAllElements();
773 }
774 else {
775 for ( int i = 0; i < size; ++i ) {
776 E element = model.getElementAt( 0 );
777 model.removeElement( element );
778 }
779 }
780 selectedItemReminder = null;
781 if (isEditable()) {
782 editor.setItem(null);
783 }
784 }
785
786 /**
787 * Checks that the <code>dataModel</code> is an instance of
788 * <code>MutableComboBoxModel</code>. If not, it throws an exception.
789 * @exception RuntimeException if <code>dataModel</code> is not an
790 * instance of <code>MutableComboBoxModel</code>.
791 */
792 void checkMutableComboBoxModel() {
793 if ( !(dataModel instanceof MutableComboBoxModel) )
794 throw new RuntimeException("Cannot use this method with a non-Mutable data model.");
795 }
796
797 /**
798 * Causes the combo box to display its popup window.
799 * @see #setPopupVisible
800 */
801 public void showPopup() {
802 setPopupVisible(true);
803 }
804
805 /**
806 * Causes the combo box to close its popup window.
807 * @see #setPopupVisible
808 */
809 public void hidePopup() {
810 setPopupVisible(false);
811 }
812
813 /**
814 * Sets the visibility of the popup.
815 */
816 public void setPopupVisible(boolean v) {
817 getUI().setPopupVisible(this, v);
818 }
819
820 /**
821 * Determines the visibility of the popup.
822 *
823 * @return true if the popup is visible, otherwise returns false
824 */
825 public boolean isPopupVisible() {
826 return getUI().isPopupVisible(this);
827 }
828
829 /** Selection **/
830
831 /**
832 * Adds an <code>ItemListener</code>.
833 * <p>
834 * <code>aListener</code> will receive one or two <code>ItemEvent</code>s when
835 * the selected item changes.
836 *
837 * @param aListener the <code>ItemListener</code> that is to be notified
838 * @see #setSelectedItem
839 */
840 public void addItemListener(ItemListener aListener) {
841 listenerList.add(ItemListener.class,aListener);
842 }
843
844 /** Removes an <code>ItemListener</code>.
845 *
846 * @param aListener the <code>ItemListener</code> to remove
847 */
848 public void removeItemListener(ItemListener aListener) {
849 listenerList.remove(ItemListener.class,aListener);
850 }
851
852 /**
853 * Returns an array of all the <code>ItemListener</code>s added
854 * to this JComboBox with addItemListener().
855 *
856 * @return all of the <code>ItemListener</code>s added or an empty
857 * array if no listeners have been added
858 * @since 1.4
859 */
860 public ItemListener[] getItemListeners() {
861 return listenerList.getListeners(ItemListener.class);
862 }
863
864 /**
865 * Adds an <code>ActionListener</code>.
866 * <p>
867 * The <code>ActionListener</code> will receive an <code>ActionEvent</code>
868 * when a selection has been made. If the combo box is editable, then
869 * an <code>ActionEvent</code> will be fired when editing has stopped.
870 *
871 * @param l the <code>ActionListener</code> that is to be notified
872 * @see #setSelectedItem
873 */
874 public void addActionListener(ActionListener l) {
875 listenerList.add(ActionListener.class,l);
876 }
877
878 /** Removes an <code>ActionListener</code>.
879 *
880 * @param l the <code>ActionListener</code> to remove
881 */
882 public void removeActionListener(ActionListener l) {
883 if ((l != null) && (getAction() == l)) {
884 setAction(null);
885 } else {
886 listenerList.remove(ActionListener.class, l);
887 }
888 }
889
890 /**
891 * Returns an array of all the <code>ActionListener</code>s added
892 * to this JComboBox with addActionListener().
893 *
894 * @return all of the <code>ActionListener</code>s added or an empty
895 * array if no listeners have been added
896 * @since 1.4
897 */
898 public ActionListener[] getActionListeners() {
899 return listenerList.getListeners(ActionListener.class);
900 }
901
902 /**
903 * Adds a <code>PopupMenu</code> listener which will listen to notification
904 * messages from the popup portion of the combo box.
905 * <p>
906 * For all standard look and feels shipped with Java, the popup list
907 * portion of combo box is implemented as a <code>JPopupMenu</code>.
908 * A custom look and feel may not implement it this way and will
909 * therefore not receive the notification.
910 *
911 * @param l the <code>PopupMenuListener</code> to add
912 * @since 1.4
913 */
914 public void addPopupMenuListener(PopupMenuListener l) {
915 listenerList.add(PopupMenuListener.class,l);
916 }
917
918 /**
919 * Removes a <code>PopupMenuListener</code>.
920 *
921 * @param l the <code>PopupMenuListener</code> to remove
922 * @see #addPopupMenuListener
923 * @since 1.4
924 */
925 public void removePopupMenuListener(PopupMenuListener l) {
926 listenerList.remove(PopupMenuListener.class,l);
927 }
928
929 /**
930 * Returns an array of all the <code>PopupMenuListener</code>s added
931 * to this JComboBox with addPopupMenuListener().
932 *
933 * @return all of the <code>PopupMenuListener</code>s added or an empty
934 * array if no listeners have been added
935 * @since 1.4
936 */
937 public PopupMenuListener[] getPopupMenuListeners() {
938 return listenerList.getListeners(PopupMenuListener.class);
939 }
940
941 /**
942 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
943 * combo box will become visible.
944 * <p>
945 * This method is public but should not be called by anything other than
946 * the UI delegate.
947 * @see #addPopupMenuListener
948 * @since 1.4
949 */
950 public void firePopupMenuWillBecomeVisible() {
951 Object[] listeners = listenerList.getListenerList();
952 PopupMenuEvent e=null;
953 for (int i = listeners.length-2; i>=0; i-=2) {
954 if (listeners[i]==PopupMenuListener.class) {
955 if (e == null)
956 e = new PopupMenuEvent(this);
957 ((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeVisible(e);
958 }
959 }
960 }
961
962 /**
963 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
964 * combo box has become invisible.
965 * <p>
966 * This method is public but should not be called by anything other than
967 * the UI delegate.
968 * @see #addPopupMenuListener
969 * @since 1.4
970 */
971 public void firePopupMenuWillBecomeInvisible() {
972 Object[] listeners = listenerList.getListenerList();
973 PopupMenuEvent e=null;
974 for (int i = listeners.length-2; i>=0; i-=2) {
975 if (listeners[i]==PopupMenuListener.class) {
976 if (e == null)
977 e = new PopupMenuEvent(this);
978 ((PopupMenuListener)listeners[i+1]).popupMenuWillBecomeInvisible(e);
979 }
980 }
981 }
982
983 /**
984 * Notifies <code>PopupMenuListener</code>s that the popup portion of the
985 * combo box has been canceled.
986 * <p>
987 * This method is public but should not be called by anything other than
988 * the UI delegate.
989 * @see #addPopupMenuListener
990 * @since 1.4
991 */
992 public void firePopupMenuCanceled() {
993 Object[] listeners = listenerList.getListenerList();
994 PopupMenuEvent e=null;
995 for (int i = listeners.length-2; i>=0; i-=2) {
996 if (listeners[i]==PopupMenuListener.class) {
997 if (e == null)
998 e = new PopupMenuEvent(this);
999 ((PopupMenuListener)listeners[i+1]).popupMenuCanceled(e);
1000 }
1001 }
1002 }
1003
1004 /**
1005 * Sets the action command that should be included in the event
1006 * sent to action listeners.
1007 *
1008 * @param aCommand a string containing the "command" that is sent
1009 * to action listeners; the same listener can then
1010 * do different things depending on the command it
1011 * receives
1012 */
1013 public void setActionCommand(String aCommand) {
1014 actionCommand = aCommand;
1015 }
1016
1017 /**
1018 * Returns the action command that is included in the event sent to
1019 * action listeners.
1020 *
1021 * @return the string containing the "command" that is sent
1022 * to action listeners.
1023 */
1024 public String getActionCommand() {
1025 return actionCommand;
1026 }
1027
1028 private Action action;
1029 private PropertyChangeListener actionPropertyChangeListener;
1030
1031 /**
1032 * Sets the <code>Action</code> for the <code>ActionEvent</code> source.
1033 * The new <code>Action</code> replaces any previously set
1034 * <code>Action</code> but does not affect <code>ActionListeners</code>
1035 * independently added with <code>addActionListener</code>.
1036 * If the <code>Action</code> is already a registered
1037 * <code>ActionListener</code> for the <code>ActionEvent</code> source,
1038 * it is not re-registered.
1039 * <p>
1040 * Setting the <code>Action</code> results in immediately changing
1041 * all the properties described in <a href="Action.html#buttonActions">
1042 * Swing Components Supporting <code>Action</code></a>.
1043 * Subsequently, the combobox's properties are automatically updated
1044 * as the <code>Action</code>'s properties change.
1045 * <p>
1046 * This method uses three other methods to set
1047 * and help track the <code>Action</code>'s property values.
1048 * It uses the <code>configurePropertiesFromAction</code> method
1049 * to immediately change the combobox's properties.
1050 * To track changes in the <code>Action</code>'s property values,
1051 * this method registers the <code>PropertyChangeListener</code>
1052 * returned by <code>createActionPropertyChangeListener</code>. The
1053 * default {@code PropertyChangeListener} invokes the
1054 * {@code actionPropertyChanged} method when a property in the
1055 * {@code Action} changes.
1056 *
1057 * @param a the <code>Action</code> for the <code>JComboBox</code>,
1058 * or <code>null</code>.
1059 * @since 1.3
1060 * @see Action
1061 * @see #getAction
1062 * @see #configurePropertiesFromAction
1063 * @see #createActionPropertyChangeListener
1064 * @see #actionPropertyChanged
1065 * @beaninfo
1066 * bound: true
1067 * attribute: visualUpdate true
1068 * description: the Action instance connected with this ActionEvent source
1069 */
1070 public void setAction(Action a) {
1071 Action oldValue = getAction();
1072 if (action==null || !action.equals(a)) {
1073 action = a;
1074 if (oldValue!=null) {
1075 removeActionListener(oldValue);
1076 oldValue.removePropertyChangeListener(actionPropertyChangeListener);
1077 actionPropertyChangeListener = null;
1078 }
1079 configurePropertiesFromAction(action);
1080 if (action!=null) {
1081 // Don't add if it is already a listener
1082 if (!isListener(ActionListener.class, action)) {
1083 addActionListener(action);
1084 }
1085 // Reverse linkage:
1086 actionPropertyChangeListener = createActionPropertyChangeListener(action);
1087 action.addPropertyChangeListener(actionPropertyChangeListener);
1088 }
1089 firePropertyChange("action", oldValue, action);
1090 }
1091 }
1092
1093 private boolean isListener(Class c, ActionListener a) {
1094 boolean isListener = false;
1095 Object[] listeners = listenerList.getListenerList();
1096 for (int i = listeners.length-2; i>=0; i-=2) {
1097 if (listeners[i]==c && listeners[i+1]==a) {
1098 isListener=true;
1099 }
1100 }
1101 return isListener;
1102 }
1103
1104 /**
1105 * Returns the currently set <code>Action</code> for this
1106 * <code>ActionEvent</code> source, or <code>null</code> if no
1107 * <code>Action</code> is set.
1108 *
1109 * @return the <code>Action</code> for this <code>ActionEvent</code>
1110 * source; or <code>null</code>
1111 * @since 1.3
1112 * @see Action
1113 * @see #setAction
1114 */
1115 public Action getAction() {
1116 return action;
1117 }
1118
1119 /**
1120 * Sets the properties on this combobox to match those in the specified
1121 * <code>Action</code>. Refer to <a href="Action.html#buttonActions">
1122 * Swing Components Supporting <code>Action</code></a> for more
1123 * details as to which properties this sets.
1124 *
1125 * @param a the <code>Action</code> from which to get the properties,
1126 * or <code>null</code>
1127 * @since 1.3
1128 * @see Action
1129 * @see #setAction
1130 */
1131 protected void configurePropertiesFromAction(Action a) {
1132 AbstractAction.setEnabledFromAction(this, a);
1133 AbstractAction.setToolTipTextFromAction(this, a);
1134 setActionCommandFromAction(a);
1135 }
1136
1137 /**
1138 * Creates and returns a <code>PropertyChangeListener</code> that is
1139 * responsible for listening for changes from the specified
1140 * <code>Action</code> and updating the appropriate properties.
1141 * <p>
1142 * <b>Warning:</b> If you subclass this do not create an anonymous
1143 * inner class. If you do the lifetime of the combobox will be tied to
1144 * that of the <code>Action</code>.
1145 *
1146 * @param a the combobox's action
1147 * @since 1.3
1148 * @see Action
1149 * @see #setAction
1150 */
1151 protected PropertyChangeListener createActionPropertyChangeListener(Action a) {
1152 return new ComboBoxActionPropertyChangeListener(this, a);
1153 }
1154
1155 /**
1156 * Updates the combobox's state in response to property changes in
1157 * associated action. This method is invoked from the
1158 * {@code PropertyChangeListener} returned from
1159 * {@code createActionPropertyChangeListener}. Subclasses do not normally
1160 * need to invoke this. Subclasses that support additional {@code Action}
1161 * properties should override this and
1162 * {@code configurePropertiesFromAction}.
1163 * <p>
1164 * Refer to the table at <a href="Action.html#buttonActions">
1165 * Swing Components Supporting <code>Action</code></a> for a list of
1166 * the properties this method sets.
1167 *
1168 * @param action the <code>Action</code> associated with this combobox
1169 * @param propertyName the name of the property that changed
1170 * @since 1.6
1171 * @see Action
1172 * @see #configurePropertiesFromAction
1173 */
1174 protected void actionPropertyChanged(Action action, String propertyName) {
1175 if (propertyName == Action.ACTION_COMMAND_KEY) {
1176 setActionCommandFromAction(action);
1177 } else if (propertyName == "enabled") {
1178 AbstractAction.setEnabledFromAction(this, action);
1179 } else if (Action.SHORT_DESCRIPTION == propertyName) {
1180 AbstractAction.setToolTipTextFromAction(this, action);
1181 }
1182 }
1183
1184 private void setActionCommandFromAction(Action a) {
1185 setActionCommand((a != null) ?
1186 (String)a.getValue(Action.ACTION_COMMAND_KEY) :
1187 null);
1188 }
1189
1190
1191 private static class ComboBoxActionPropertyChangeListener
1192 extends ActionPropertyChangeListener<JComboBox<?>> {
1193 ComboBoxActionPropertyChangeListener(JComboBox<?> b, Action a) {
1194 super(b, a);
1195 }
1196 protected void actionPropertyChanged(JComboBox<?> cb,
1197 Action action,
1198 PropertyChangeEvent e) {
1199 if (AbstractAction.shouldReconfigure(e)) {
1200 cb.configurePropertiesFromAction(action);
1201 } else {
1202 cb.actionPropertyChanged(action, e.getPropertyName());
1203 }
1204 }
1205 }
1206
1207 /**
1208 * Notifies all listeners that have registered interest for
1209 * notification on this event type.
1210 * @param e the event of interest
1211 *
1212 * @see EventListenerList
1213 */
1214 protected void fireItemStateChanged(ItemEvent e) {
1215 // Guaranteed to return a non-null array
1216 Object[] listeners = listenerList.getListenerList();
1217 // Process the listeners last to first, notifying
1218 // those that are interested in this event
1219 for ( int i = listeners.length-2; i>=0; i-=2 ) {
1220 if ( listeners[i]==ItemListener.class ) {
1221 // Lazily create the event:
1222 // if (changeEvent == null)
1223 // changeEvent = new ChangeEvent(this);
1224 ((ItemListener)listeners[i+1]).itemStateChanged(e);
1225 }
1226 }
1227 }
1228
1229 /**
1230 * Notifies all listeners that have registered interest for
1231 * notification on this event type.
1232 *
1233 * @see EventListenerList
1234 */
1235 protected void fireActionEvent() {
1236 if (!firingActionEvent) {
1237 // Set flag to ensure that an infinite loop is not created
1238 firingActionEvent = true;
1239 ActionEvent e = null;
1240 // Guaranteed to return a non-null array
1241 Object[] listeners = listenerList.getListenerList();
1242 long mostRecentEventTime = EventQueue.getMostRecentEventTime();
1243 int modifiers = 0;
1244 AWTEvent currentEvent = EventQueue.getCurrentEvent();
1245 if (currentEvent instanceof InputEvent) {
1246 modifiers = ((InputEvent)currentEvent).getModifiers();
1247 } else if (currentEvent instanceof ActionEvent) {
1248 modifiers = ((ActionEvent)currentEvent).getModifiers();
1249 }
1250 // Process the listeners last to first, notifying
1251 // those that are interested in this event
1252 for ( int i = listeners.length-2; i>=0; i-=2 ) {
1253 if ( listeners[i]==ActionListener.class ) {
1254 // Lazily create the event:
1255 if ( e == null )
1256 e = new ActionEvent(this,ActionEvent.ACTION_PERFORMED,
1257 getActionCommand(),
1258 mostRecentEventTime, modifiers);
1259 ((ActionListener)listeners[i+1]).actionPerformed(e);
1260 }
1261 }
1262 firingActionEvent = false;
1263 }
1264 }
1265
1266 /**
1267 * This protected method is implementation specific. Do not access directly
1268 * or override.
1269 */
1270 protected void selectedItemChanged() {
1271 if (selectedItemReminder != null ) {
1272 fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
1273 selectedItemReminder,
1274 ItemEvent.DESELECTED));
1275 }
1276
1277 // set the new selected item.
1278 selectedItemReminder = dataModel.getSelectedItem();
1279
1280 if (selectedItemReminder != null ) {
1281 fireItemStateChanged(new ItemEvent(this,ItemEvent.ITEM_STATE_CHANGED,
1282 selectedItemReminder,
1283 ItemEvent.SELECTED));
1284 }
1285 }
1286
1287 /**
1288 * Returns an array containing the selected item.
1289 * This method is implemented for compatibility with
1290 * <code>ItemSelectable</code>.
1291 *
1292 * @return an array of <code>Objects</code> containing one
1293 * element -- the selected item
1294 */
1295 public Object[] getSelectedObjects() {
1296 Object selectedObject = getSelectedItem();
1297 if ( selectedObject == null )
1298 return new Object[0];
1299 else {
1300 Object result[] = new Object[1];
1301 result[0] = selectedObject;
1302 return result;
1303 }
1304 }
1305
1306 /**
1307 * This method is public as an implementation side effect.
1308 * do not call or override.
1309 */
1310 public void actionPerformed(ActionEvent e) {
1311 ComboBoxEditor editor = getEditor();
1312 if ((editor != null) && (e != null) && (editor == e.getSource())) {
1313 setPopupVisible(false);
1314 getModel().setSelectedItem(editor.getItem());
1315 String oldCommand = getActionCommand();
1316 setActionCommand("comboBoxEdited");
1317 fireActionEvent();
1318 setActionCommand(oldCommand);
1319 }
1320 }
1321
1322 /**
1323 * This method is public as an implementation side effect.
1324 * do not call or override.
1325 */
1326 public void contentsChanged(ListDataEvent e) {
1327 Object oldSelection = selectedItemReminder;
1328 Object newSelection = dataModel.getSelectedItem();
1329 if (oldSelection == null || !oldSelection.equals(newSelection)) {
1330 selectedItemChanged();
1331 if (!selectingItem) {
1332 fireActionEvent();
1333 }
1334 }
1335 }
1336
1337 /**
1338 * This method is public as an implementation side effect.
1339 * do not call or override.
1340 */
1341 public void intervalAdded(ListDataEvent e) {
1342 if (selectedItemReminder != dataModel.getSelectedItem()) {
1343 selectedItemChanged();
1344 }
1345 }
1346
1347 /**
1348 * This method is public as an implementation side effect.
1349 * do not call or override.
1350 */
1351 public void intervalRemoved(ListDataEvent e) {
1352 contentsChanged(e);
1353 }
1354
1355 /**
1356 * Selects the list item that corresponds to the specified keyboard
1357 * character and returns true, if there is an item corresponding
1358 * to that character. Otherwise, returns false.
1359 *
1360 * @param keyChar a char, typically this is a keyboard key
1361 * typed by the user
1362 */
1363 public boolean selectWithKeyChar(char keyChar) {
1364 int index;
1365
1366 if ( keySelectionManager == null )
1367 keySelectionManager = createDefaultKeySelectionManager();
1368
1369 index = keySelectionManager.selectionForKey(keyChar,getModel());
1370 if ( index != -1 ) {
1371 setSelectedIndex(index);
1372 return true;
1373 }
1374 else
1375 return false;
1376 }
1377
1378 /**
1379 * Enables the combo box so that items can be selected. When the
1380 * combo box is disabled, items cannot be selected and values
1381 * cannot be typed into its field (if it is editable).
1382 *
1383 * @param b a boolean value, where true enables the component and
1384 * false disables it
1385 * @beaninfo
1386 * bound: true
1387 * preferred: true
1388 * description: Whether the combo box is enabled.
1389 */
1390 public void setEnabled(boolean b) {
1391 super.setEnabled(b);
1392 firePropertyChange( "enabled", !isEnabled(), isEnabled() );
1393 }
1394
1395 /**
1396 * Initializes the editor with the specified item.
1397 *
1398 * @param anEditor the <code>ComboBoxEditor</code> that displays
1399 * the list item in the
1400 * combo box field and allows it to be edited
1401 * @param anItem the object to display and edit in the field
1402 */
1403 public void configureEditor(ComboBoxEditor anEditor, Object anItem) {
1404 anEditor.setItem(anItem);
1405 }
1406
1407 /**
1408 * Handles <code>KeyEvent</code>s, looking for the Tab key.
1409 * If the Tab key is found, the popup window is closed.
1410 *
1411 * @param e the <code>KeyEvent</code> containing the keyboard
1412 * key that was pressed
1413 */
1414 public void processKeyEvent(KeyEvent e) {
1415 if ( e.getKeyCode() == KeyEvent.VK_TAB ) {
1416 hidePopup();
1417 }
1418 super.processKeyEvent(e);
1419 }
1420
1421 /**
1422 * {@inheritDoc}
1423 */
1424 @Override
1425 protected boolean processKeyBinding(KeyStroke ks, KeyEvent e, int condition, boolean pressed) {
1426 if (super.processKeyBinding(ks, e, condition, pressed)) {
1427 return true;
1428 }
1429
1430 if (!isEditable() || condition != WHEN_FOCUSED || getEditor() == null
1431 || !Boolean.TRUE.equals(getClientProperty("JComboBox.isTableCellEditor"))) {
1432 return false;
1433 }
1434
1435 Component editorComponent = getEditor().getEditorComponent();
1436 if (editorComponent instanceof JComponent) {
1437 JComponent component = (JComponent) editorComponent;
1438 return component.processKeyBinding(ks, e, WHEN_FOCUSED, pressed);
1439 }
1440 return false;
1441 }
1442
1443 /**
1444 * Sets the object that translates a keyboard character into a list
1445 * selection. Typically, the first selection with a matching first
1446 * character becomes the selected item.
1447 *
1448 * @beaninfo
1449 * expert: true
1450 * description: The objects that changes the selection when a key is pressed.
1451 */
1452 public void setKeySelectionManager(KeySelectionManager aManager) {
1453 keySelectionManager = aManager;
1454 }
1455
1456 /**
1457 * Returns the list's key-selection manager.
1458 *
1459 * @return the <code>KeySelectionManager</code> currently in use
1460 */
1461 public KeySelectionManager getKeySelectionManager() {
1462 return keySelectionManager;
1463 }
1464
1465 /* Accessing the model */
1466 /**
1467 * Returns the number of items in the list.
1468 *
1469 * @return an integer equal to the number of items in the list
1470 */
1471 public int getItemCount() {
1472 return dataModel.getSize();
1473 }
1474
1475 /**
1476 * Returns the list item at the specified index. If <code>index</code>
1477 * is out of range (less than zero or greater than or equal to size)
1478 * it will return <code>null</code>.
1479 *
1480 * @param index an integer indicating the list position, where the first
1481 * item starts at zero
1482 * @return the item at that list position; or
1483 * <code>null</code> if out of range
1484 */
1485 public E getItemAt(int index) {
1486 return dataModel.getElementAt(index);
1487 }
1488
1489 /**
1490 * Returns an instance of the default key-selection manager.
1491 *
1492 * @return the <code>KeySelectionManager</code> currently used by the list
1493 * @see #setKeySelectionManager
1494 */
1495 protected KeySelectionManager createDefaultKeySelectionManager() {
1496 return new DefaultKeySelectionManager();
1497 }
1498
1499
1500 /**
1501 * The interface that defines a <code>KeySelectionManager</code>.
1502 * To qualify as a <code>KeySelectionManager</code>,
1503 * the class needs to implement the method
1504 * that identifies the list index given a character and the
1505 * combo box data model.
1506 */
1507 public interface KeySelectionManager {
1508 /** Given <code>aKey</code> and the model, returns the row
1509 * that should become selected. Return -1 if no match was
1510 * found.
1511 *
1512 * @param aKey a char value, usually indicating a keyboard key that
1513 * was pressed
1514 * @param aModel a ComboBoxModel -- the component's data model, containing
1515 * the list of selectable items
1516 * @return an int equal to the selected row, where 0 is the
1517 * first item and -1 is none.
1518 */
1519 int selectionForKey(char aKey,ComboBoxModel aModel);
1520 }
1521
1522 class DefaultKeySelectionManager implements KeySelectionManager, Serializable {
1523 public int selectionForKey(char aKey,ComboBoxModel aModel) {
1524 int i,c;
1525 int currentSelection = -1;
1526 Object selectedItem = aModel.getSelectedItem();
1527 String v;
1528 String pattern;
1529
1530 if ( selectedItem != null ) {
1531 for ( i=0,c=aModel.getSize();i<c;i++ ) {
1532 if ( selectedItem == aModel.getElementAt(i) ) {
1533 currentSelection = i;
1534 break;
1535 }
1536 }
1537 }
1538
1539 pattern = ("" + aKey).toLowerCase();
1540 aKey = pattern.charAt(0);
1541
1542 for ( i = ++currentSelection, c = aModel.getSize() ; i < c ; i++ ) {
1543 Object elem = aModel.getElementAt(i);
1544 if (elem != null && elem.toString() != null) {
1545 v = elem.toString().toLowerCase();
1546 if ( v.length() > 0 && v.charAt(0) == aKey )
1547 return i;
1548 }
1549 }
1550
1551 for ( i = 0 ; i < currentSelection ; i ++ ) {
1552 Object elem = aModel.getElementAt(i);
1553 if (elem != null && elem.toString() != null) {
1554 v = elem.toString().toLowerCase();
1555 if ( v.length() > 0 && v.charAt(0) == aKey )
1556 return i;
1557 }
1558 }
1559 return -1;
1560 }
1561 }
1562
1563
1564 /**
1565 * See <code>readObject</code> and <code>writeObject</code> in
1566 * <code>JComponent</code> for more
1567 * information about serialization in Swing.
1568 */
1569 private void writeObject(ObjectOutputStream s) throws IOException {
1570 s.defaultWriteObject();
1571 if (getUIClassID().equals(uiClassID)) {
1572 byte count = JComponent.getWriteObjCounter(this);
1573 JComponent.setWriteObjCounter(this, --count);
1574 if (count == 0 && ui != null) {
1575 ui.installUI(this);
1576 }
1577 }
1578 }
1579
1580
1581 /**
1582 * Returns a string representation of this <code>JComboBox</code>.
1583 * This method is intended to be used only for debugging purposes,
1584 * and the content and format of the returned string may vary between
1585 * implementations. The returned string may be empty but may not
1586 * be <code>null</code>.
1587 *
1588 * @return a string representation of this <code>JComboBox</code>
1589 */
1590 protected String paramString() {
1591 String selectedItemReminderString = (selectedItemReminder != null ?
1592 selectedItemReminder.toString() :
1593 "");
1594 String isEditableString = (isEditable ? "true" : "false");
1595 String lightWeightPopupEnabledString = (lightWeightPopupEnabled ?
1596 "true" : "false");
1597
1598 return super.paramString() +
1599 ",isEditable=" + isEditableString +
1600 ",lightWeightPopupEnabled=" + lightWeightPopupEnabledString +
1601 ",maximumRowCount=" + maximumRowCount +
1602 ",selectedItemReminder=" + selectedItemReminderString;
1603 }
1604
1605
1606 ///////////////////
1607 // Accessibility support
1608 ///////////////////
1609
1610 /**
1611 * Gets the AccessibleContext associated with this JComboBox.
1612 * For combo boxes, the AccessibleContext takes the form of an
1613 * AccessibleJComboBox.
1614 * A new AccessibleJComboBox instance is created if necessary.
1615 *
1616 * @return an AccessibleJComboBox that serves as the
1617 * AccessibleContext of this JComboBox
1618 */
1619 public AccessibleContext getAccessibleContext() {
1620 if ( accessibleContext == null ) {
1621 accessibleContext = new AccessibleJComboBox();
1622 }
1623 return accessibleContext;
1624 }
1625
1626 /**
1627 * This class implements accessibility support for the
1628 * <code>JComboBox</code> class. It provides an implementation of the
1629 * Java Accessibility API appropriate to Combo Box user-interface elements.
1630 * <p>
1631 * <strong>Warning:</strong>
1632 * Serialized objects of this class will not be compatible with
1633 * future Swing releases. The current serialization support is
1634 * appropriate for short term storage or RMI between applications running
1635 * the same version of Swing. As of 1.4, support for long term storage
1636 * of all JavaBeans™
1637 * has been added to the <code>java.beans</code> package.
1638 * Please see {@link java.beans.XMLEncoder}.
1639 */
1640 @SuppressWarnings("serial") // Same-version serialization only
1641 protected class AccessibleJComboBox extends AccessibleJComponent
1642 implements AccessibleAction, AccessibleSelection {
1643
1644
1645 private JList popupList; // combo box popup list
1646 private Accessible previousSelectedAccessible = null;
1647
1648 /**
1649 * Returns an AccessibleJComboBox instance
1650 * @since 1.4
1651 */
1652 public AccessibleJComboBox() {
1653 // set the combo box editor's accessible name and description
1654 JComboBox.this.addPropertyChangeListener(new AccessibleJComboBoxPropertyChangeListener());
1655 setEditorNameAndDescription();
1656
1657 // Get the popup list
1658 Accessible a = getUI().getAccessibleChild(JComboBox.this, 0);
1659 if (a instanceof javax.swing.plaf.basic.ComboPopup) {
1660 // Listen for changes to the popup menu selection.
1661 popupList = ((javax.swing.plaf.basic.ComboPopup)a).getList();
1662 popupList.addListSelectionListener(
1663 new AccessibleJComboBoxListSelectionListener());
1664 }
1665 // Listen for popup menu show/hide events
1666 JComboBox.this.addPopupMenuListener(
1667 new AccessibleJComboBoxPopupMenuListener());
1668 }
1669
1670 /*
1671 * JComboBox PropertyChangeListener
1672 */
1673 private class AccessibleJComboBoxPropertyChangeListener
1674 implements PropertyChangeListener {
1675
1676 public void propertyChange(PropertyChangeEvent e) {
1677 if (e.getPropertyName() == "editor") {
1678 // set the combo box editor's accessible name
1679 // and description
1680 setEditorNameAndDescription();
1681 }
1682 }
1683 }
1684
1685 /*
1686 * Sets the combo box editor's accessible name and descripton
1687 */
1688 private void setEditorNameAndDescription() {
1689 ComboBoxEditor editor = JComboBox.this.getEditor();
1690 if (editor != null) {
1691 Component comp = editor.getEditorComponent();
1692 if (comp instanceof Accessible) {
1693 AccessibleContext ac = comp.getAccessibleContext();
1694 if (ac != null) { // may be null
1695 ac.setAccessibleName(getAccessibleName());
1696 ac.setAccessibleDescription(getAccessibleDescription());
1697 }
1698 }
1699 }
1700 }
1701
1702 /*
1703 * Listener for combo box popup menu
1704 * TIGER - 4669379 4894434
1705 */
1706 private class AccessibleJComboBoxPopupMenuListener
1707 implements PopupMenuListener {
1708
1709 /**
1710 * This method is called before the popup menu becomes visible
1711 */
1712 public void popupMenuWillBecomeVisible(PopupMenuEvent e) {
1713 // save the initial selection
1714 if (popupList == null) {
1715 return;
1716 }
1717 int selectedIndex = popupList.getSelectedIndex();
1718 if (selectedIndex < 0) {
1719 return;
1720 }
1721 previousSelectedAccessible =
1722 popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
1723 }
1724
1725 /**
1726 * This method is called before the popup menu becomes invisible
1727 * Note that a JPopupMenu can become invisible any time
1728 */
1729 public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {
1730 // ignore
1731 }
1732
1733 /**
1734 * This method is called when the popup menu is canceled
1735 */
1736 public void popupMenuCanceled(PopupMenuEvent e) {
1737 // ignore
1738 }
1739 }
1740
1741 /*
1742 * Handles changes to the popup list selection.
1743 * TIGER - 4669379 4894434 4933143
1744 */
1745 private class AccessibleJComboBoxListSelectionListener
1746 implements ListSelectionListener {
1747
1748 public void valueChanged(ListSelectionEvent e) {
1749 if (popupList == null) {
1750 return;
1751 }
1752
1753 // Get the selected popup list item.
1754 int selectedIndex = popupList.getSelectedIndex();
1755 if (selectedIndex < 0) {
1756 return;
1757 }
1758 Accessible selectedAccessible =
1759 popupList.getAccessibleContext().getAccessibleChild(selectedIndex);
1760 if (selectedAccessible == null) {
1761 return;
1762 }
1763
1764 // Fire a FOCUSED lost PropertyChangeEvent for the
1765 // previously selected list item.
1766 PropertyChangeEvent pce;
1767
1768 if (previousSelectedAccessible != null) {
1769 pce = new PropertyChangeEvent(previousSelectedAccessible,
1770 AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1771 AccessibleState.FOCUSED, null);
1772 firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1773 null, pce);
1774 }
1775 // Fire a FOCUSED gained PropertyChangeEvent for the
1776 // currently selected list item.
1777 pce = new PropertyChangeEvent(selectedAccessible,
1778 AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1779 null, AccessibleState.FOCUSED);
1780 firePropertyChange(AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
1781 null, pce);
1782
1783 // Fire the ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY event
1784 // for the combo box.
1785 firePropertyChange(AccessibleContext.ACCESSIBLE_ACTIVE_DESCENDANT_PROPERTY,
1786 previousSelectedAccessible, selectedAccessible);
1787
1788 // Save the previous selection.
1789 previousSelectedAccessible = selectedAccessible;
1790 }
1791 }
1792
1793
1794 /**
1795 * Returns the number of accessible children in the object. If all
1796 * of the children of this object implement Accessible, than this
1797 * method should return the number of children of this object.
1798 *
1799 * @return the number of accessible children in the object.
1800 */
1801 public int getAccessibleChildrenCount() {
1802 // Always delegate to the UI if it exists
1803 if (ui != null) {
1804 return ui.getAccessibleChildrenCount(JComboBox.this);
1805 } else {
1806 return super.getAccessibleChildrenCount();
1807 }
1808 }
1809
1810 /**
1811 * Returns the nth Accessible child of the object.
1812 * The child at index zero represents the popup.
1813 * If the combo box is editable, the child at index one
1814 * represents the editor.
1815 *
1816 * @param i zero-based index of child
1817 * @return the nth Accessible child of the object
1818 */
1819 public Accessible getAccessibleChild(int i) {
1820 // Always delegate to the UI if it exists
1821 if (ui != null) {
1822 return ui.getAccessibleChild(JComboBox.this, i);
1823 } else {
1824 return super.getAccessibleChild(i);
1825 }
1826 }
1827
1828 /**
1829 * Get the role of this object.
1830 *
1831 * @return an instance of AccessibleRole describing the role of the
1832 * object
1833 * @see AccessibleRole
1834 */
1835 public AccessibleRole getAccessibleRole() {
1836 return AccessibleRole.COMBO_BOX;
1837 }
1838
1839 /**
1840 * Gets the state set of this object. The AccessibleStateSet of
1841 * an object is composed of a set of unique AccessibleStates.
1842 * A change in the AccessibleStateSet of an object will cause a
1843 * PropertyChangeEvent to be fired for the ACCESSIBLE_STATE_PROPERTY
1844 * property.
1845 *
1846 * @return an instance of AccessibleStateSet containing the
1847 * current state set of the object
1848 * @see AccessibleStateSet
1849 * @see AccessibleState
1850 * @see #addPropertyChangeListener
1851 *
1852 */
1853 public AccessibleStateSet getAccessibleStateSet() {
1854 // TIGER - 4489748
1855 AccessibleStateSet ass = super.getAccessibleStateSet();
1856 if (ass == null) {
1857 ass = new AccessibleStateSet();
1858 }
1859 if (JComboBox.this.isPopupVisible()) {
1860 ass.add(AccessibleState.EXPANDED);
1861 } else {
1862 ass.add(AccessibleState.COLLAPSED);
1863 }
1864 return ass;
1865 }
1866
1867 /**
1868 * Get the AccessibleAction associated with this object. In the
1869 * implementation of the Java Accessibility API for this class,
1870 * return this object, which is responsible for implementing the
1871 * AccessibleAction interface on behalf of itself.
1872 *
1873 * @return this object
1874 */
1875 public AccessibleAction getAccessibleAction() {
1876 return this;
1877 }
1878
1879 /**
1880 * Return a description of the specified action of the object.
1881 *
1882 * @param i zero-based index of the actions
1883 */
1884 public String getAccessibleActionDescription(int i) {
1885 if (i == 0) {
1886 return UIManager.getString("ComboBox.togglePopupText");
1887 }
1888 else {
1889 return null;
1890 }
1891 }
1892
1893 /**
1894 * Returns the number of Actions available in this object. The
1895 * default behavior of a combo box is to have one action.
1896 *
1897 * @return 1, the number of Actions in this object
1898 */
1899 public int getAccessibleActionCount() {
1900 return 1;
1901 }
1902
1903 /**
1904 * Perform the specified Action on the object
1905 *
1906 * @param i zero-based index of actions
1907 * @return true if the the action was performed; else false.
1908 */
1909 public boolean doAccessibleAction(int i) {
1910 if (i == 0) {
1911 setPopupVisible(!isPopupVisible());
1912 return true;
1913 }
1914 else {
1915 return false;
1916 }
1917 }
1918
1919
1920 /**
1921 * Get the AccessibleSelection associated with this object. In the
1922 * implementation of the Java Accessibility API for this class,
1923 * return this object, which is responsible for implementing the
1924 * AccessibleSelection interface on behalf of itself.
1925 *
1926 * @return this object
1927 */
1928 public AccessibleSelection getAccessibleSelection() {
1929 return this;
1930 }
1931
1932 /**
1933 * Returns the number of Accessible children currently selected.
1934 * If no children are selected, the return value will be 0.
1935 *
1936 * @return the number of items currently selected.
1937 * @since 1.3
1938 */
1939 public int getAccessibleSelectionCount() {
1940 Object o = JComboBox.this.getSelectedItem();
1941 if (o != null) {
1942 return 1;
1943 } else {
1944 return 0;
1945 }
1946 }
1947
1948 /**
1949 * Returns an Accessible representing the specified selected child
1950 * in the popup. If there isn't a selection, or there are
1951 * fewer children selected than the integer passed in, the return
1952 * value will be null.
1953 * <p>Note that the index represents the i-th selected child, which
1954 * is different from the i-th child.
1955 *
1956 * @param i the zero-based index of selected children
1957 * @return the i-th selected child
1958 * @see #getAccessibleSelectionCount
1959 * @since 1.3
1960 */
1961 public Accessible getAccessibleSelection(int i) {
1962 // Get the popup
1963 Accessible a =
1964 JComboBox.this.getUI().getAccessibleChild(JComboBox.this, 0);
1965 if (a != null &&
1966 a instanceof javax.swing.plaf.basic.ComboPopup) {
1967
1968 // get the popup list
1969 JList list = ((javax.swing.plaf.basic.ComboPopup)a).getList();
1970
1971 // return the i-th selection in the popup list
1972 AccessibleContext ac = list.getAccessibleContext();
1973 if (ac != null) {
1974 AccessibleSelection as = ac.getAccessibleSelection();
1975 if (as != null) {
1976 return as.getAccessibleSelection(i);
1977 }
1978 }
1979 }
1980 return null;
1981 }
1982
1983 /**
1984 * Determines if the current child of this object is selected.
1985 *
1986 * @return true if the current child of this object is selected;
1987 * else false
1988 * @param i the zero-based index of the child in this Accessible
1989 * object.
1990 * @see AccessibleContext#getAccessibleChild
1991 * @since 1.3
1992 */
1993 public boolean isAccessibleChildSelected(int i) {
1994 return JComboBox.this.getSelectedIndex() == i;
1995 }
1996
1997 /**
1998 * Adds the specified Accessible child of the object to the object's
1999 * selection. If the object supports multiple selections,
2000 * the specified child is added to any existing selection, otherwise
2001 * it replaces any existing selection in the object. If the
2002 * specified child is already selected, this method has no effect.
2003 *
2004 * @param i the zero-based index of the child
2005 * @see AccessibleContext#getAccessibleChild
2006 * @since 1.3
2007 */
2008 public void addAccessibleSelection(int i) {
2009 // TIGER - 4856195
2010 clearAccessibleSelection();
2011 JComboBox.this.setSelectedIndex(i);
2012 }
2013
2014 /**
2015 * Removes the specified child of the object from the object's
2016 * selection. If the specified item isn't currently selected, this
2017 * method has no effect.
2018 *
2019 * @param i the zero-based index of the child
2020 * @see AccessibleContext#getAccessibleChild
2021 * @since 1.3
2022 */
2023 public void removeAccessibleSelection(int i) {
2024 if (JComboBox.this.getSelectedIndex() == i) {
2025 clearAccessibleSelection();
2026 }
2027 }
2028
2029 /**
2030 * Clears the selection in the object, so that no children in the
2031 * object are selected.
2032 * @since 1.3
2033 */
2034 public void clearAccessibleSelection() {
2035 JComboBox.this.setSelectedIndex(-1);
2036 }
2037
2038 /**
2039 * Causes every child of the object to be selected
2040 * if the object supports multiple selections.
2041 * @since 1.3
2042 */
2043 public void selectAllAccessibleSelection() {
2044 // do nothing since multiple selection is not supported
2045 }
2046
2047 // public Accessible getAccessibleAt(Point p) {
2048 // Accessible a = getAccessibleChild(1);
2049 // if ( a != null ) {
2050 // return a; // the editor
2051 // }
2052 // else {
2053 // return getAccessibleChild(0); // the list
2054 // }
2055 // }
2056 private EditorAccessibleContext editorAccessibleContext = null;
2057
2058 private class AccessibleEditor implements Accessible {
2059 public AccessibleContext getAccessibleContext() {
2060 if (editorAccessibleContext == null) {
2061 Component c = JComboBox.this.getEditor().getEditorComponent();
2062 if (c instanceof Accessible) {
2063 editorAccessibleContext =
2064 new EditorAccessibleContext((Accessible)c);
2065 }
2066 }
2067 return editorAccessibleContext;
2068 }
2069 }
2070
2071 /*
2072 * Wrapper class for the AccessibleContext implemented by the
2073 * combo box editor. Delegates all method calls except
2074 * getAccessibleIndexInParent to the editor. The
2075 * getAccessibleIndexInParent method returns the selected
2076 * index in the combo box.
2077 */
2078 private class EditorAccessibleContext extends AccessibleContext {
2079
2080 private AccessibleContext ac;
2081
2082 private EditorAccessibleContext() {
2083 }
2084
2085 /*
2086 * @param a the AccessibleContext implemented by the
2087 * combo box editor
2088 */
2089 EditorAccessibleContext(Accessible a) {
2090 this.ac = a.getAccessibleContext();
2091 }
2092
2093 /**
2094 * Gets the accessibleName property of this object. The accessibleName
2095 * property of an object is a localized String that designates the purpose
2096 * of the object. For example, the accessibleName property of a label
2097 * or button might be the text of the label or button itself. In the
2098 * case of an object that doesn't display its name, the accessibleName
2099 * should still be set. For example, in the case of a text field used
2100 * to enter the name of a city, the accessibleName for the en_US locale
2101 * could be 'city.'
2102 *
2103 * @return the localized name of the object; null if this
2104 * object does not have a name
2105 *
2106 * @see #setAccessibleName
2107 */
2108 public String getAccessibleName() {
2109 return ac.getAccessibleName();
2110 }
2111
2112 /**
2113 * Sets the localized accessible name of this object. Changing the
2114 * name will cause a PropertyChangeEvent to be fired for the
2115 * ACCESSIBLE_NAME_PROPERTY property.
2116 *
2117 * @param s the new localized name of the object.
2118 *
2119 * @see #getAccessibleName
2120 * @see #addPropertyChangeListener
2121 *
2122 * @beaninfo
2123 * preferred: true
2124 * description: Sets the accessible name for the component.
2125 */
2126 public void setAccessibleName(String s) {
2127 ac.setAccessibleName(s);
2128 }
2129
2130 /**
2131 * Gets the accessibleDescription property of this object. The
2132 * accessibleDescription property of this object is a short localized
2133 * phrase describing the purpose of the object. For example, in the
2134 * case of a 'Cancel' button, the accessibleDescription could be
2135 * 'Ignore changes and close dialog box.'
2136 *
2137 * @return the localized description of the object; null if
2138 * this object does not have a description
2139 *
2140 * @see #setAccessibleDescription
2141 */
2142 public String getAccessibleDescription() {
2143 return ac.getAccessibleDescription();
2144 }
2145
2146 /**
2147 * Sets the accessible description of this object. Changing the
2148 * name will cause a PropertyChangeEvent to be fired for the
2149 * ACCESSIBLE_DESCRIPTION_PROPERTY property.
2150 *
2151 * @param s the new localized description of the object
2152 *
2153 * @see #setAccessibleName
2154 * @see #addPropertyChangeListener
2155 *
2156 * @beaninfo
2157 * preferred: true
2158 * description: Sets the accessible description for the component.
2159 */
2160 public void setAccessibleDescription(String s) {
2161 ac.setAccessibleDescription(s);
2162 }
2163
2164 /**
2165 * Gets the role of this object. The role of the object is the generic
2166 * purpose or use of the class of this object. For example, the role
2167 * of a push button is AccessibleRole.PUSH_BUTTON. The roles in
2168 * AccessibleRole are provided so component developers can pick from
2169 * a set of predefined roles. This enables assistive technologies to
2170 * provide a consistent interface to various tweaked subclasses of
2171 * components (e.g., use AccessibleRole.PUSH_BUTTON for all components
2172 * that act like a push button) as well as distinguish between subclasses
2173 * that behave differently (e.g., AccessibleRole.CHECK_BOX for check boxes
2174 * and AccessibleRole.RADIO_BUTTON for radio buttons).
2175 * <p>Note that the AccessibleRole class is also extensible, so
2176 * custom component developers can define their own AccessibleRole's
2177 * if the set of predefined roles is inadequate.
2178 *
2179 * @return an instance of AccessibleRole describing the role of the object
2180 * @see AccessibleRole
2181 */
2182 public AccessibleRole getAccessibleRole() {
2183 return ac.getAccessibleRole();
2184 }
2185
2186 /**
2187 * Gets the state set of this object. The AccessibleStateSet of an object
2188 * is composed of a set of unique AccessibleStates. A change in the
2189 * AccessibleStateSet of an object will cause a PropertyChangeEvent to
2190 * be fired for the ACCESSIBLE_STATE_PROPERTY property.
2191 *
2192 * @return an instance of AccessibleStateSet containing the
2193 * current state set of the object
2194 * @see AccessibleStateSet
2195 * @see AccessibleState
2196 * @see #addPropertyChangeListener
2197 */
2198 public AccessibleStateSet getAccessibleStateSet() {
2199 return ac.getAccessibleStateSet();
2200 }
2201
2202 /**
2203 * Gets the Accessible parent of this object.
2204 *
2205 * @return the Accessible parent of this object; null if this
2206 * object does not have an Accessible parent
2207 */
2208 public Accessible getAccessibleParent() {
2209 return ac.getAccessibleParent();
2210 }
2211
2212 /**
2213 * Sets the Accessible parent of this object. This is meant to be used
2214 * only in the situations where the actual component's parent should
2215 * not be treated as the component's accessible parent and is a method
2216 * that should only be called by the parent of the accessible child.
2217 *
2218 * @param a - Accessible to be set as the parent
2219 */
2220 public void setAccessibleParent(Accessible a) {
2221 ac.setAccessibleParent(a);
2222 }
2223
2224 /**
2225 * Gets the 0-based index of this object in its accessible parent.
2226 *
2227 * @return the 0-based index of this object in its parent; -1 if this
2228 * object does not have an accessible parent.
2229 *
2230 * @see #getAccessibleParent
2231 * @see #getAccessibleChildrenCount
2232 * @see #getAccessibleChild
2233 */
2234 public int getAccessibleIndexInParent() {
2235 return JComboBox.this.getSelectedIndex();
2236 }
2237
2238 /**
2239 * Returns the number of accessible children of the object.
2240 *
2241 * @return the number of accessible children of the object.
2242 */
2243 public int getAccessibleChildrenCount() {
2244 return ac.getAccessibleChildrenCount();
2245 }
2246
2247 /**
2248 * Returns the specified Accessible child of the object. The Accessible
2249 * children of an Accessible object are zero-based, so the first child
2250 * of an Accessible child is at index 0, the second child is at index 1,
2251 * and so on.
2252 *
2253 * @param i zero-based index of child
2254 * @return the Accessible child of the object
2255 * @see #getAccessibleChildrenCount
2256 */
2257 public Accessible getAccessibleChild(int i) {
2258 return ac.getAccessibleChild(i);
2259 }
2260
2261 /**
2262 * Gets the locale of the component. If the component does not have a
2263 * locale, then the locale of its parent is returned.
2264 *
2265 * @return this component's locale. If this component does not have
2266 * a locale, the locale of its parent is returned.
2267 *
2268 * @exception IllegalComponentStateException
2269 * If the Component does not have its own locale and has not yet been
2270 * added to a containment hierarchy such that the locale can be
2271 * determined from the containing parent.
2272 */
2273 public Locale getLocale() throws IllegalComponentStateException {
2274 return ac.getLocale();
2275 }
2276
2277 /**
2278 * Adds a PropertyChangeListener to the listener list.
2279 * The listener is registered for all Accessible properties and will
2280 * be called when those properties change.
2281 *
2282 * @see #ACCESSIBLE_NAME_PROPERTY
2283 * @see #ACCESSIBLE_DESCRIPTION_PROPERTY
2284 * @see #ACCESSIBLE_STATE_PROPERTY
2285 * @see #ACCESSIBLE_VALUE_PROPERTY
2286 * @see #ACCESSIBLE_SELECTION_PROPERTY
2287 * @see #ACCESSIBLE_TEXT_PROPERTY
2288 * @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
2289 *
2290 * @param listener The PropertyChangeListener to be added
2291 */
2292 public void addPropertyChangeListener(PropertyChangeListener listener) {
2293 ac.addPropertyChangeListener(listener);
2294 }
2295
2296 /**
2297 * Removes a PropertyChangeListener from the listener list.
2298 * This removes a PropertyChangeListener that was registered
2299 * for all properties.
2300 *
2301 * @param listener The PropertyChangeListener to be removed
2302 */
2303 public void removePropertyChangeListener(PropertyChangeListener listener) {
2304 ac.removePropertyChangeListener(listener);
2305 }
2306
2307 /**
2308 * Gets the AccessibleAction associated with this object that supports
2309 * one or more actions.
2310 *
2311 * @return AccessibleAction if supported by object; else return null
2312 * @see AccessibleAction
2313 */
2314 public AccessibleAction getAccessibleAction() {
2315 return ac.getAccessibleAction();
2316 }
2317
2318 /**
2319 * Gets the AccessibleComponent associated with this object that has a
2320 * graphical representation.
2321 *
2322 * @return AccessibleComponent if supported by object; else return null
2323 * @see AccessibleComponent
2324 */
2325 public AccessibleComponent getAccessibleComponent() {
2326 return ac.getAccessibleComponent();
2327 }
2328
2329 /**
2330 * Gets the AccessibleSelection associated with this object which allows its
2331 * Accessible children to be selected.
2332 *
2333 * @return AccessibleSelection if supported by object; else return null
2334 * @see AccessibleSelection
2335 */
2336 public AccessibleSelection getAccessibleSelection() {
2337 return ac.getAccessibleSelection();
2338 }
2339
2340 /**
2341 * Gets the AccessibleText associated with this object presenting
2342 * text on the display.
2343 *
2344 * @return AccessibleText if supported by object; else return null
2345 * @see AccessibleText
2346 */
2347 public AccessibleText getAccessibleText() {
2348 return ac.getAccessibleText();
2349 }
2350
2351 /**
2352 * Gets the AccessibleEditableText associated with this object
2353 * presenting editable text on the display.
2354 *
2355 * @return AccessibleEditableText if supported by object; else return null
2356 * @see AccessibleEditableText
2357 */
2358 public AccessibleEditableText getAccessibleEditableText() {
2359 return ac.getAccessibleEditableText();
2360 }
2361
2362 /**
2363 * Gets the AccessibleValue associated with this object that supports a
2364 * Numerical value.
2365 *
2366 * @return AccessibleValue if supported by object; else return null
2367 * @see AccessibleValue
2368 */
2369 public AccessibleValue getAccessibleValue() {
2370 return ac.getAccessibleValue();
2371 }
2372
2373 /**
2374 * Gets the AccessibleIcons associated with an object that has
2375 * one or more associated icons
2376 *
2377 * @return an array of AccessibleIcon if supported by object;
2378 * otherwise return null
2379 * @see AccessibleIcon
2380 */
2381 public AccessibleIcon [] getAccessibleIcon() {
2382 return ac.getAccessibleIcon();
2383 }
2384
2385 /**
2386 * Gets the AccessibleRelationSet associated with an object
2387 *
2388 * @return an AccessibleRelationSet if supported by object;
2389 * otherwise return null
2390 * @see AccessibleRelationSet
2391 */
2392 public AccessibleRelationSet getAccessibleRelationSet() {
2393 return ac.getAccessibleRelationSet();
2394 }
2395
2396 /**
2397 * Gets the AccessibleTable associated with an object
2398 *
2399 * @return an AccessibleTable if supported by object;
2400 * otherwise return null
2401 * @see AccessibleTable
2402 */
2403 public AccessibleTable getAccessibleTable() {
2404 return ac.getAccessibleTable();
2405 }
2406
2407 /**
2408 * Support for reporting bound property changes. If oldValue and
2409 * newValue are not equal and the PropertyChangeEvent listener list
2410 * is not empty, then fire a PropertyChange event to each listener.
2411 * In general, this is for use by the Accessible objects themselves
2412 * and should not be called by an application program.
2413 * @param propertyName The programmatic name of the property that
2414 * was changed.
2415 * @param oldValue The old value of the property.
2416 * @param newValue The new value of the property.
2417 * @see java.beans.PropertyChangeSupport
2418 * @see #addPropertyChangeListener
2419 * @see #removePropertyChangeListener
2420 * @see #ACCESSIBLE_NAME_PROPERTY
2421 * @see #ACCESSIBLE_DESCRIPTION_PROPERTY
2422 * @see #ACCESSIBLE_STATE_PROPERTY
2423 * @see #ACCESSIBLE_VALUE_PROPERTY
2424 * @see #ACCESSIBLE_SELECTION_PROPERTY
2425 * @see #ACCESSIBLE_TEXT_PROPERTY
2426 * @see #ACCESSIBLE_VISIBLE_DATA_PROPERTY
2427 */
2428 public void firePropertyChange(String propertyName,
2429 Object oldValue,
2430 Object newValue) {
2431 ac.firePropertyChange(propertyName, oldValue, newValue);
2432 }
2433 }
2434
2435 } // innerclass AccessibleJComboBox
2436 }