1 /*
2 * Copyright (c) 1997, 2006, 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
26 package javax.swing;
27
28 import java.util.List;
29 import java.util.ArrayList;
30 import java.util.Vector;
31 import javax.swing.plaf.*;
32 import javax.accessibility.*;
33
34 import java.awt.Component;
35 import java.awt.Container;
36 import java.awt.DefaultFocusTraversalPolicy;
37 import java.awt.FocusTraversalPolicy;
38 import java.awt.Window;
39 import java.io.ObjectOutputStream;
40 import java.io.ObjectInputStream;
41 import java.io.IOException;
42 import java.beans.PropertyVetoException;
43 import java.util.Set;
44 import java.util.TreeSet;
45
46 /**
47 * A container used to create a multiple-document interface or a virtual desktop.
48 * You create <code>JInternalFrame</code> objects and add them to the
49 * <code>JDesktopPane</code>. <code>JDesktopPane</code> extends
50 * <code>JLayeredPane</code> to manage the potentially overlapping internal
51 * frames. It also maintains a reference to an instance of
52 * <code>DesktopManager</code> that is set by the UI
53 * class for the current look and feel (L&F). Note that <code>JDesktopPane</code>
54 * does not support borders.
55 * <p>
56 * This class is normally used as the parent of <code>JInternalFrames</code>
57 * to provide a pluggable <code>DesktopManager</code> object to the
58 * <code>JInternalFrames</code>. The <code>installUI</code> of the
59 * L&F specific implementation is responsible for setting the
60 * <code>desktopManager</code> variable appropriately.
61 * When the parent of a <code>JInternalFrame</code> is a <code>JDesktopPane</code>,
62 * it should delegate most of its behavior to the <code>desktopManager</code>
63 * (closing, resizing, etc).
64 * <p>
65 * For further documentation and examples see
66 * <a href="http://java.sun.com/docs/books/tutorial/uiswing/components/internalframe.html">How to Use Internal Frames</a>,
67 * a section in <em>The Java Tutorial</em>.
68 * <p>
69 * <strong>Warning:</strong> Swing is not thread safe. For more
70 * information see <a
71 * href="package-summary.html#threading">Swing's Threading
72 * Policy</a>.
73 * <p>
74 * <strong>Warning:</strong>
75 * Serialized objects of this class will not be compatible with
76 * future Swing releases. The current serialization support is
77 * appropriate for short term storage or RMI between applications running
78 * the same version of Swing. As of 1.4, support for long term storage
79 * of all JavaBeans<sup><font size="-2">TM</font></sup>
80 * has been added to the <code>java.beans</code> package.
81 * Please see {@link java.beans.XMLEncoder}.
82 *
83 * @see JInternalFrame
84 * @see JInternalFrame.JDesktopIcon
85 * @see DesktopManager
86 *
87 * @author David Kloba
88 */
89 public class JDesktopPane extends JLayeredPane implements Accessible
90 {
91 /**
92 * @see #getUIClassID
93 * @see #readObject
94 */
95 private static final String uiClassID = "DesktopPaneUI";
96
97 transient DesktopManager desktopManager;
98
99 private transient JInternalFrame selectedFrame = null;
100
101 /**
102 * Indicates that the entire contents of the item being dragged
103 * should appear inside the desktop pane.
104 *
105 * @see #OUTLINE_DRAG_MODE
106 * @see #setDragMode
107 */
108 public static final int LIVE_DRAG_MODE = 0;
109
110 /**
111 * Indicates that an outline only of the item being dragged
112 * should appear inside the desktop pane.
113 *
114 * @see #LIVE_DRAG_MODE
115 * @see #setDragMode
116 */
117 public static final int OUTLINE_DRAG_MODE = 1;
118
119 private int dragMode = LIVE_DRAG_MODE;
120 private boolean dragModeSet = false;
121 private transient List<JInternalFrame> framesCache;
122 private boolean componentOrderCheckingEnabled = true;
123 private boolean componentOrderChanged = false;
124
125 /**
126 * Creates a new <code>JDesktopPane</code>.
127 */
128 public JDesktopPane() {
129 setUIProperty("opaque", Boolean.TRUE);
130 setFocusCycleRoot(true);
131
132 setFocusTraversalPolicy(new LayoutFocusTraversalPolicy() {
133 public Component getDefaultComponent(Container c) {
134 JInternalFrame jifArray[] = getAllFrames();
135 Component comp = null;
136 for (JInternalFrame jif : jifArray) {
137 comp = jif.getFocusTraversalPolicy().getDefaultComponent(jif);
138 if (comp != null) {
139 break;
140 }
141 }
142 return comp;
143 }
144 });
145 updateUI();
146 }
147
148 /**
149 * Returns the L&F object that renders this component.
150 *
151 * @return the <code>DesktopPaneUI</code> object that
152 * renders this component
153 */
154 public DesktopPaneUI getUI() {
155 return (DesktopPaneUI)ui;
156 }
157
158 /**
159 * Sets the L&F object that renders this component.
160 *
161 * @param ui the DesktopPaneUI L&F object
162 * @see UIDefaults#getUI
163 * @beaninfo
164 * bound: true
165 * hidden: true
166 * attribute: visualUpdate true
167 * description: The UI object that implements the Component's LookAndFeel.
168 */
169 public void setUI(DesktopPaneUI ui) {
170 super.setUI(ui);
171 }
172
173 /**
174 * Sets the "dragging style" used by the desktop pane.
175 * You may want to change to one mode or another for
176 * performance or aesthetic reasons.
177 *
178 * @param dragMode the style of drag to use for items in the Desktop
179 *
180 * @see #LIVE_DRAG_MODE
181 * @see #OUTLINE_DRAG_MODE
182 *
183 * @beaninfo
184 * bound: true
185 * description: Dragging style for internal frame children.
186 * enum: LIVE_DRAG_MODE JDesktopPane.LIVE_DRAG_MODE
187 * OUTLINE_DRAG_MODE JDesktopPane.OUTLINE_DRAG_MODE
188 * @since 1.3
189 */
190 public void setDragMode(int dragMode) {
191 int oldDragMode = this.dragMode;
192 this.dragMode = dragMode;
193 firePropertyChange("dragMode", oldDragMode, this.dragMode);
194 dragModeSet = true;
195 }
196
197 /**
198 * Gets the current "dragging style" used by the desktop pane.
199 * @return either <code>Live_DRAG_MODE</code> or
200 * <code>OUTLINE_DRAG_MODE</code>
201 * @see #setDragMode
202 * @since 1.3
203 */
204 public int getDragMode() {
205 return dragMode;
206 }
207
208 /**
209 * Returns the <code>DesktopManger</code> that handles
210 * desktop-specific UI actions.
211 */
212 public DesktopManager getDesktopManager() {
213 return desktopManager;
214 }
215
216 /**
217 * Sets the <code>DesktopManger</code> that will handle
218 * desktop-specific UI actions.
219 *
220 * @param d the <code>DesktopManager</code> to use
221 *
222 * @beaninfo
223 * bound: true
224 * description: Desktop manager to handle the internal frames in the
225 * desktop pane.
226 */
227 public void setDesktopManager(DesktopManager d) {
228 DesktopManager oldValue = desktopManager;
229 desktopManager = d;
230 firePropertyChange("desktopManager", oldValue, desktopManager);
231 }
232
233 /**
234 * Notification from the <code>UIManager</code> that the L&F has changed.
235 * Replaces the current UI object with the latest version from the
236 * <code>UIManager</code>.
237 *
238 * @see JComponent#updateUI
239 */
240 public void updateUI() {
241 setUI((DesktopPaneUI)UIManager.getUI(this));
242 }
243
244
245 /**
246 * Returns the name of the L&F class that renders this component.
247 *
248 * @return the string "DesktopPaneUI"
249 * @see JComponent#getUIClassID
250 * @see UIDefaults#getUI
251 */
252 public String getUIClassID() {
253 return uiClassID;
254 }
255
256 /**
257 * Returns all <code>JInternalFrames</code> currently displayed in the
258 * desktop. Returns iconified frames as well as expanded frames.
259 *
260 * @return an array of <code>JInternalFrame</code> objects
261 */
262 public JInternalFrame[] getAllFrames() {
263 int i, count;
264 JInternalFrame[] results;
265 Vector<JInternalFrame> vResults = new Vector<JInternalFrame>(10);
266
267 count = getComponentCount();
268 for(i = 0; i < count; i++) {
269 Component next = getComponent(i);
270 if(next instanceof JInternalFrame)
271 vResults.addElement((JInternalFrame) next);
272 else if(next instanceof JInternalFrame.JDesktopIcon) {
273 JInternalFrame tmp = ((JInternalFrame.JDesktopIcon)next).getInternalFrame();
274 if(tmp != null)
275 vResults.addElement(tmp);
276 }
277 }
278
279 results = new JInternalFrame[vResults.size()];
280 vResults.copyInto(results);
281
282 return results;
283 }
284
285 /** Returns the currently active <code>JInternalFrame</code>
286 * in this <code>JDesktopPane</code>, or <code>null</code>
287 * if no <code>JInternalFrame</code> is currently active.
288 *
289 * @return the currently active <code>JInternalFrame</code> or
290 * <code>null</code>
291 * @since 1.3
292 */
293
294 public JInternalFrame getSelectedFrame() {
295 return selectedFrame;
296 }
297
298 /** Sets the currently active <code>JInternalFrame</code>
299 * in this <code>JDesktopPane</code>. This method is used to bridge
300 * the package gap between JDesktopPane and the platform implementation
301 * code and should not be called directly. To visually select the frame
302 * the client must call JInternalFrame.setSelected(true) to activate
303 * the frame.
304 * @see JInternalFrame#setSelected(boolean)
305 *
306 * @param f the internal frame that's currently selected
307 * @since 1.3
308 */
309
310 public void setSelectedFrame(JInternalFrame f) {
311 selectedFrame = f;
312 }
313
314 /**
315 * Returns all <code>JInternalFrames</code> currently displayed in the
316 * specified layer of the desktop. Returns iconified frames as well
317 * expanded frames.
318 *
319 * @param layer an int specifying the desktop layer
320 * @return an array of <code>JInternalFrame</code> objects
321 * @see JLayeredPane
322 */
323 public JInternalFrame[] getAllFramesInLayer(int layer) {
324 int i, count;
325 JInternalFrame[] results;
326 Vector<JInternalFrame> vResults = new Vector<JInternalFrame>(10);
327
328 count = getComponentCount();
329 for(i = 0; i < count; i++) {
330 Component next = getComponent(i);
331 if(next instanceof JInternalFrame) {
332 if(((JInternalFrame)next).getLayer() == layer)
333 vResults.addElement((JInternalFrame) next);
334 } else if(next instanceof JInternalFrame.JDesktopIcon) {
335 JInternalFrame tmp = ((JInternalFrame.JDesktopIcon)next).getInternalFrame();
336 if(tmp != null && tmp.getLayer() == layer)
337 vResults.addElement(tmp);
338 }
339 }
340
341 results = new JInternalFrame[vResults.size()];
342 vResults.copyInto(results);
343
344 return results;
345 }
346
347 private List<JInternalFrame> getFrames() {
348 Component c;
349 Set<ComponentPosition> set = new TreeSet<ComponentPosition>();
350 for (int i = 0; i < getComponentCount(); i++) {
351 c = getComponent(i);
352 if (c instanceof JInternalFrame) {
353 set.add(new ComponentPosition((JInternalFrame)c, getLayer(c),
354 i));
355 }
356 else if (c instanceof JInternalFrame.JDesktopIcon) {
357 c = ((JInternalFrame.JDesktopIcon)c).getInternalFrame();
358 set.add(new ComponentPosition((JInternalFrame)c, getLayer(c),
359 i));
360 }
361 }
362 List<JInternalFrame> frames = new ArrayList<JInternalFrame>(
363 set.size());
364 for (ComponentPosition position : set) {
365 frames.add(position.component);
366 }
367 return frames;
368 }
369
370 private static class ComponentPosition implements
371 Comparable<ComponentPosition> {
372 private final JInternalFrame component;
373 private final int layer;
374 private final int zOrder;
375
376 ComponentPosition(JInternalFrame component, int layer, int zOrder) {
377 this.component = component;
378 this.layer = layer;
379 this.zOrder = zOrder;
380 }
381
382 public int compareTo(ComponentPosition o) {
383 int delta = o.layer - layer;
384 if (delta == 0) {
385 return zOrder - o.zOrder;
386 }
387 return delta;
388 }
389 }
390
391 private JInternalFrame getNextFrame(JInternalFrame f, boolean forward) {
392 verifyFramesCache();
393 if (f == null) {
394 return getTopInternalFrame();
395 }
396 int i = framesCache.indexOf(f);
397 if (i == -1 || framesCache.size() == 1) {
398 /* error */
399 return null;
400 }
401 if (forward) {
402 // navigate to the next frame
403 if (++i == framesCache.size()) {
404 /* wrap */
405 i = 0;
406 }
407 }
408 else {
409 // navigate to the previous frame
410 if (--i == -1) {
411 /* wrap */
412 i = framesCache.size() - 1;
413 }
414 }
415 return framesCache.get(i);
416 }
417
418 JInternalFrame getNextFrame(JInternalFrame f) {
419 return getNextFrame(f, true);
420 }
421
422 private JInternalFrame getTopInternalFrame() {
423 if (framesCache.size() == 0) {
424 return null;
425 }
426 return framesCache.get(0);
427 }
428
429 private void updateFramesCache() {
430 framesCache = getFrames();
431 }
432
433 private void verifyFramesCache() {
434 // If framesCache is dirty, then recreate it.
435 if (componentOrderChanged) {
436 componentOrderChanged = false;
437 updateFramesCache();
438 }
439 }
440
441 /**
442 * Selects the next <code>JInternalFrame</code> in this desktop pane.
443 *
444 * @param forward a boolean indicating which direction to select in;
445 * <code>true</code> for forward, <code>false</code> for
446 * backward
447 * @return the JInternalFrame that was selected or <code>null</code>
448 * if nothing was selected
449 * @since 1.6
450 */
451 public JInternalFrame selectFrame(boolean forward) {
452 JInternalFrame selectedFrame = getSelectedFrame();
453 JInternalFrame frameToSelect = getNextFrame(selectedFrame, forward);
454 if (frameToSelect == null) {
455 return null;
456 }
457 // Maintain navigation traversal order until an
458 // external stack change, such as a click on a frame.
459 setComponentOrderCheckingEnabled(false);
460 if (forward && selectedFrame != null) {
461 selectedFrame.moveToBack(); // For Windows MDI fidelity.
462 }
463 try { frameToSelect.setSelected(true);
464 } catch (PropertyVetoException pve) {}
465 setComponentOrderCheckingEnabled(true);
466 return frameToSelect;
467 }
468
469 /*
470 * Sets whether component order checking is enabled.
471 * @param enable a boolean value, where <code>true</code> means
472 * a change in component order will cause a change in the keyboard
473 * navigation order.
474 * @since 1.6
475 */
476 void setComponentOrderCheckingEnabled(boolean enable) {
477 componentOrderCheckingEnabled = enable;
478 }
479
480 /**
481 * {@inheritDoc}
482 * @since 1.6
483 */
484 protected void addImpl(Component comp, Object constraints, int index) {
485 super.addImpl(comp, constraints, index);
486 if (componentOrderCheckingEnabled) {
487 if (comp instanceof JInternalFrame ||
488 comp instanceof JInternalFrame.JDesktopIcon) {
489 componentOrderChanged = true;
490 }
491 }
492 }
493
494 /**
495 * {@inheritDoc}
496 * @since 1.6
497 */
498 public void remove(int index) {
499 if (componentOrderCheckingEnabled) {
500 Component comp = getComponent(index);
501 if (comp instanceof JInternalFrame ||
502 comp instanceof JInternalFrame.JDesktopIcon) {
503 componentOrderChanged = true;
504 }
505 }
506 super.remove(index);
507 }
508
509 /**
510 * {@inheritDoc}
511 * @since 1.6
512 */
513 public void removeAll() {
514 if (componentOrderCheckingEnabled) {
515 int count = getComponentCount();
516 for (int i = 0; i < count; i++) {
517 Component comp = getComponent(i);
518 if (comp instanceof JInternalFrame ||
519 comp instanceof JInternalFrame.JDesktopIcon) {
520 componentOrderChanged = true;
521 break;
522 }
523 }
524 }
525 super.removeAll();
526 }
527
528 /**
529 * {@inheritDoc}
530 * @since 1.6
531 */
532 public void setComponentZOrder(Component comp, int index) {
533 super.setComponentZOrder(comp, index);
534 if (componentOrderCheckingEnabled) {
535 if (comp instanceof JInternalFrame ||
536 comp instanceof JInternalFrame.JDesktopIcon) {
537 componentOrderChanged = true;
538 }
539 }
540 }
541
542 /**
543 * See readObject() and writeObject() in JComponent for more
544 * information about serialization in Swing.
545 */
546 private void writeObject(ObjectOutputStream s) throws IOException {
547 s.defaultWriteObject();
548 if (getUIClassID().equals(uiClassID)) {
549 byte count = JComponent.getWriteObjCounter(this);
550 JComponent.setWriteObjCounter(this, --count);
551 if (count == 0 && ui != null) {
552 ui.installUI(this);
553 }
554 }
555 }
556
557 void setUIProperty(String propertyName, Object value) {
558 if (propertyName == "dragMode") {
559 if (!dragModeSet) {
560 setDragMode(((Integer)value).intValue());
561 dragModeSet = false;
562 }
563 } else {
564 super.setUIProperty(propertyName, value);
565 }
566 }
567
568 /**
569 * Returns a string representation of this <code>JDesktopPane</code>.
570 * This method is intended to be used only for debugging purposes, and the
571 * content and format of the returned string may vary between
572 * implementations. The returned string may be empty but may not
573 * be <code>null</code>.
574 *
575 * @return a string representation of this <code>JDesktopPane</code>
576 */
577 protected String paramString() {
578 String desktopManagerString = (desktopManager != null ?
579 desktopManager.toString() : "");
580
581 return super.paramString() +
582 ",desktopManager=" + desktopManagerString;
583 }
584
585 /////////////////
586 // Accessibility support
587 ////////////////
588
589 /**
590 * Gets the <code>AccessibleContext</code> associated with this
591 * <code>JDesktopPane</code>. For desktop panes, the
592 * <code>AccessibleContext</code> takes the form of an
593 * <code>AccessibleJDesktopPane</code>.
594 * A new <code>AccessibleJDesktopPane</code> instance is created if necessary.
595 *
596 * @return an <code>AccessibleJDesktopPane</code> that serves as the
597 * <code>AccessibleContext</code> of this <code>JDesktopPane</code>
598 */
599 public AccessibleContext getAccessibleContext() {
600 if (accessibleContext == null) {
601 accessibleContext = new AccessibleJDesktopPane();
602 }
603 return accessibleContext;
604 }
605
606 /**
607 * This class implements accessibility support for the
608 * <code>JDesktopPane</code> class. It provides an implementation of the
609 * Java Accessibility API appropriate to desktop pane user-interface
610 * elements.
611 * <p>
612 * <strong>Warning:</strong>
613 * Serialized objects of this class will not be compatible with
614 * future Swing releases. The current serialization support is
615 * appropriate for short term storage or RMI between applications running
616 * the same version of Swing. As of 1.4, support for long term storage
617 * of all JavaBeans<sup><font size="-2">TM</font></sup>
618 * has been added to the <code>java.beans</code> package.
619 * Please see {@link java.beans.XMLEncoder}.
620 */
621 protected class AccessibleJDesktopPane extends AccessibleJComponent {
622
623 /**
624 * Get the role of this object.
625 *
626 * @return an instance of AccessibleRole describing the role of the
627 * object
628 * @see AccessibleRole
629 */
630 public AccessibleRole getAccessibleRole() {
631 return AccessibleRole.DESKTOP_PANE;
632 }
633 }
634 }