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