1 /*
2 * Copyright (c) 1997, 2010, 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. This may be overridden by
219 * {@code LookAndFeel}.
220 *
221 * @param d the <code>DesktopManager</code> to use
222 *
223 * @beaninfo
224 * bound: true
225 * description: Desktop manager to handle the internal frames in the
226 * desktop pane.
227 */
228 public void setDesktopManager(DesktopManager d) {
229 DesktopManager oldValue = desktopManager;
230 desktopManager = d;
231 firePropertyChange("desktopManager", oldValue, desktopManager);
232 }
233
234 /**
235 * Notification from the <code>UIManager</code> that the L&F has changed.
236 * Replaces the current UI object with the latest version from the
237 * <code>UIManager</code>.
238 *
239 * @see JComponent#updateUI
240 */
241 public void updateUI() {
242 setUI((DesktopPaneUI)UIManager.getUI(this));
243 }
244
245
246 /**
247 * Returns the name of the L&F class that renders this component.
248 *
249 * @return the string "DesktopPaneUI"
250 * @see JComponent#getUIClassID
251 * @see UIDefaults#getUI
252 */
253 public String getUIClassID() {
254 return uiClassID;
255 }
256
257 /**
258 * Returns all <code>JInternalFrames</code> currently displayed in the
259 * desktop. Returns iconified frames as well as expanded frames.
260 *
261 * @return an array of <code>JInternalFrame</code> objects
262 */
263 public JInternalFrame[] getAllFrames() {
264 int i, count;
265 JInternalFrame[] results;
266 Vector<JInternalFrame> vResults = new Vector<JInternalFrame>(10);
267
268 count = getComponentCount();
269 for(i = 0; i < count; i++) {
270 Component next = getComponent(i);
271 if(next instanceof JInternalFrame)
272 vResults.addElement((JInternalFrame) next);
273 else if(next instanceof JInternalFrame.JDesktopIcon) {
274 JInternalFrame tmp = ((JInternalFrame.JDesktopIcon)next).getInternalFrame();
275 if(tmp != null)
276 vResults.addElement(tmp);
277 }
278 }
279
280 results = new JInternalFrame[vResults.size()];
281 vResults.copyInto(results);
282
283 return results;
284 }
285
286 /** Returns the currently active <code>JInternalFrame</code>
287 * in this <code>JDesktopPane</code>, or <code>null</code>
288 * if no <code>JInternalFrame</code> is currently active.
289 *
290 * @return the currently active <code>JInternalFrame</code> or
291 * <code>null</code>
292 * @since 1.3
293 */
294
295 public JInternalFrame getSelectedFrame() {
296 return selectedFrame;
297 }
298
299 /** Sets the currently active <code>JInternalFrame</code>
300 * in this <code>JDesktopPane</code>. This method is used to bridge
301 * the package gap between JDesktopPane and the platform implementation
302 * code and should not be called directly. To visually select the frame
303 * the client must call JInternalFrame.setSelected(true) to activate
304 * the frame.
305 * @see JInternalFrame#setSelected(boolean)
306 *
307 * @param f the internal frame that's currently selected
308 * @since 1.3
309 */
310
311 public void setSelectedFrame(JInternalFrame f) {
312 selectedFrame = f;
313 }
314
315 /**
316 * Returns all <code>JInternalFrames</code> currently displayed in the
317 * specified layer of the desktop. Returns iconified frames as well
318 * expanded frames.
319 *
320 * @param layer an int specifying the desktop layer
321 * @return an array of <code>JInternalFrame</code> objects
322 * @see JLayeredPane
323 */
324 public JInternalFrame[] getAllFramesInLayer(int layer) {
325 int i, count;
326 JInternalFrame[] results;
327 Vector<JInternalFrame> vResults = new Vector<JInternalFrame>(10);
328
329 count = getComponentCount();
330 for(i = 0; i < count; i++) {
331 Component next = getComponent(i);
332 if(next instanceof JInternalFrame) {
333 if(((JInternalFrame)next).getLayer() == layer)
334 vResults.addElement((JInternalFrame) next);
335 } else if(next instanceof JInternalFrame.JDesktopIcon) {
336 JInternalFrame tmp = ((JInternalFrame.JDesktopIcon)next).getInternalFrame();
337 if(tmp != null && tmp.getLayer() == layer)
338 vResults.addElement(tmp);
339 }
340 }
341
342 results = new JInternalFrame[vResults.size()];
343 vResults.copyInto(results);
344
345 return results;
346 }
347
348 private List<JInternalFrame> getFrames() {
349 Component c;
350 Set<ComponentPosition> set = new TreeSet<ComponentPosition>();
351 for (int i = 0; i < getComponentCount(); i++) {
352 c = getComponent(i);
353 if (c instanceof JInternalFrame) {
354 set.add(new ComponentPosition((JInternalFrame)c, getLayer(c),
355 i));
356 }
357 else if (c instanceof JInternalFrame.JDesktopIcon) {
358 c = ((JInternalFrame.JDesktopIcon)c).getInternalFrame();
359 set.add(new ComponentPosition((JInternalFrame)c, getLayer(c),
360 i));
361 }
362 }
363 List<JInternalFrame> frames = new ArrayList<JInternalFrame>(
364 set.size());
365 for (ComponentPosition position : set) {
366 frames.add(position.component);
367 }
368 return frames;
369 }
370
371 private static class ComponentPosition implements
372 Comparable<ComponentPosition> {
373 private final JInternalFrame component;
374 private final int layer;
375 private final int zOrder;
376
377 ComponentPosition(JInternalFrame component, int layer, int zOrder) {
378 this.component = component;
379 this.layer = layer;
380 this.zOrder = zOrder;
381 }
382
383 public int compareTo(ComponentPosition o) {
384 int delta = o.layer - layer;
385 if (delta == 0) {
386 return zOrder - o.zOrder;
387 }
388 return delta;
389 }
390 }
391
392 private JInternalFrame getNextFrame(JInternalFrame f, boolean forward) {
393 verifyFramesCache();
394 if (f == null) {
395 return getTopInternalFrame();
396 }
397 int i = framesCache.indexOf(f);
398 if (i == -1 || framesCache.size() == 1) {
399 /* error */
400 return null;
401 }
402 if (forward) {
403 // navigate to the next frame
404 if (++i == framesCache.size()) {
405 /* wrap */
406 i = 0;
407 }
408 }
409 else {
410 // navigate to the previous frame
411 if (--i == -1) {
412 /* wrap */
413 i = framesCache.size() - 1;
414 }
415 }
416 return framesCache.get(i);
417 }
418
419 JInternalFrame getNextFrame(JInternalFrame f) {
420 return getNextFrame(f, true);
421 }
422
423 private JInternalFrame getTopInternalFrame() {
424 if (framesCache.size() == 0) {
425 return null;
426 }
427 return framesCache.get(0);
428 }
429
430 private void updateFramesCache() {
431 framesCache = getFrames();
432 }
433
434 private void verifyFramesCache() {
435 // If framesCache is dirty, then recreate it.
436 if (componentOrderChanged) {
437 componentOrderChanged = false;
438 updateFramesCache();
439 }
440 }
441
442 /**
443 * Selects the next <code>JInternalFrame</code> in this desktop pane.
444 *
445 * @param forward a boolean indicating which direction to select in;
446 * <code>true</code> for forward, <code>false</code> for
447 * backward
448 * @return the JInternalFrame that was selected or <code>null</code>
449 * if nothing was selected
450 * @since 1.6
451 */
452 public JInternalFrame selectFrame(boolean forward) {
453 JInternalFrame selectedFrame = getSelectedFrame();
454 JInternalFrame frameToSelect = getNextFrame(selectedFrame, forward);
455 if (frameToSelect == null) {
456 return null;
457 }
458 // Maintain navigation traversal order until an
459 // external stack change, such as a click on a frame.
460 setComponentOrderCheckingEnabled(false);
461 if (forward && selectedFrame != null) {
462 selectedFrame.moveToBack(); // For Windows MDI fidelity.
463 }
464 try { frameToSelect.setSelected(true);
465 } catch (PropertyVetoException pve) {}
466 setComponentOrderCheckingEnabled(true);
467 return frameToSelect;
468 }
469
470 /*
471 * Sets whether component order checking is enabled.
472 * @param enable a boolean value, where <code>true</code> means
473 * a change in component order will cause a change in the keyboard
474 * navigation order.
475 * @since 1.6
476 */
477 void setComponentOrderCheckingEnabled(boolean enable) {
478 componentOrderCheckingEnabled = enable;
479 }
480
481 /**
482 * {@inheritDoc}
483 * @since 1.6
484 */
485 protected void addImpl(Component comp, Object constraints, int index) {
486 super.addImpl(comp, constraints, index);
487 if (componentOrderCheckingEnabled) {
488 if (comp instanceof JInternalFrame ||
489 comp instanceof JInternalFrame.JDesktopIcon) {
490 componentOrderChanged = true;
491 }
492 }
493 }
494
495 /**
496 * {@inheritDoc}
497 * @since 1.6
498 */
499 public void remove(int index) {
500 if (componentOrderCheckingEnabled) {
501 Component comp = getComponent(index);
502 if (comp instanceof JInternalFrame ||
503 comp instanceof JInternalFrame.JDesktopIcon) {
504 componentOrderChanged = true;
505 }
506 }
507 super.remove(index);
508 }
509
510 /**
511 * {@inheritDoc}
512 * @since 1.6
513 */
514 public void removeAll() {
515 if (componentOrderCheckingEnabled) {
516 int count = getComponentCount();
517 for (int i = 0; i < count; i++) {
518 Component comp = getComponent(i);
519 if (comp instanceof JInternalFrame ||
520 comp instanceof JInternalFrame.JDesktopIcon) {
521 componentOrderChanged = true;
522 break;
523 }
524 }
525 }
526 super.removeAll();
527 }
528
529 /**
530 * {@inheritDoc}
531 * @since 1.6
532 */
533 public void setComponentZOrder(Component comp, int index) {
534 super.setComponentZOrder(comp, index);
535 if (componentOrderCheckingEnabled) {
536 if (comp instanceof JInternalFrame ||
537 comp instanceof JInternalFrame.JDesktopIcon) {
538 componentOrderChanged = true;
539 }
540 }
541 }
542
543 /**
544 * See readObject() and writeObject() in JComponent for more
545 * information about serialization in Swing.
546 */
547 private void writeObject(ObjectOutputStream s) throws IOException {
548 s.defaultWriteObject();
549 if (getUIClassID().equals(uiClassID)) {
550 byte count = JComponent.getWriteObjCounter(this);
551 JComponent.setWriteObjCounter(this, --count);
552 if (count == 0 && ui != null) {
553 ui.installUI(this);
554 }
555 }
556 }
557
558 void setUIProperty(String propertyName, Object value) {
559 if (propertyName == "dragMode") {
560 if (!dragModeSet) {
561 setDragMode(((Integer)value).intValue());
562 dragModeSet = false;
563 }
564 } else {
565 super.setUIProperty(propertyName, value);
566 }
567 }
568
569 /**
570 * Returns a string representation of this <code>JDesktopPane</code>.
571 * This method is intended to be used only for debugging purposes, and the
572 * content and format of the returned string may vary between
573 * implementations. The returned string may be empty but may not
574 * be <code>null</code>.
575 *
576 * @return a string representation of this <code>JDesktopPane</code>
577 */
578 protected String paramString() {
579 String desktopManagerString = (desktopManager != null ?
580 desktopManager.toString() : "");
581
582 return super.paramString() +
583 ",desktopManager=" + desktopManagerString;
584 }
585
586 /////////////////
587 // Accessibility support
588 ////////////////
589
590 /**
591 * Gets the <code>AccessibleContext</code> associated with this
592 * <code>JDesktopPane</code>. For desktop panes, the
593 * <code>AccessibleContext</code> takes the form of an
594 * <code>AccessibleJDesktopPane</code>.
595 * A new <code>AccessibleJDesktopPane</code> instance is created if necessary.
596 *
597 * @return an <code>AccessibleJDesktopPane</code> that serves as the
598 * <code>AccessibleContext</code> of this <code>JDesktopPane</code>
599 */
600 public AccessibleContext getAccessibleContext() {
601 if (accessibleContext == null) {
602 accessibleContext = new AccessibleJDesktopPane();
603 }
604 return accessibleContext;
605 }
606
607 /**
608 * This class implements accessibility support for the
609 * <code>JDesktopPane</code> class. It provides an implementation of the
610 * Java Accessibility API appropriate to desktop pane user-interface
611 * elements.
612 * <p>
613 * <strong>Warning:</strong>
614 * Serialized objects of this class will not be compatible with
615 * future Swing releases. The current serialization support is
616 * appropriate for short term storage or RMI between applications running
617 * the same version of Swing. As of 1.4, support for long term storage
618 * of all JavaBeans<sup><font size="-2">TM</font></sup>
619 * has been added to the <code>java.beans</code> package.
620 * Please see {@link java.beans.XMLEncoder}.
621 */
622 protected class AccessibleJDesktopPane extends AccessibleJComponent {
623
624 /**
625 * Get the role of this object.
626 *
627 * @return an instance of AccessibleRole describing the role of the
628 * object
629 * @see AccessibleRole
630 */
631 public AccessibleRole getAccessibleRole() {
632 return AccessibleRole.DESKTOP_PANE;
633 }
634 }
635 }