1 /*
2 * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package javax.swing;
27
28 import java.util.List;
29 import java.util.ArrayList;
30 import java.util.Collection;
31 import java.util.Iterator;
32 import javax.swing.plaf.*;
33 import javax.accessibility.*;
34
35 import java.awt.Component;
36 import java.awt.Container;
37 import java.awt.DefaultFocusTraversalPolicy;
38 import java.awt.FocusTraversalPolicy;
39 import java.awt.Window;
40 import java.io.ObjectOutputStream;
41 import java.io.ObjectInputStream;
42 import java.io.IOException;
43 import java.beans.PropertyVetoException;
44 import java.util.Set;
45 import java.util.TreeSet;
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://docs.oracle.com/javase/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™
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 * @since 1.2
89 */
90 @SuppressWarnings("serial") // Same-version serialization only
91 public class JDesktopPane extends JLayeredPane implements Accessible
92 {
93 /**
94 * @see #getUIClassID
95 * @see #readObject
96 */
97 private static final String uiClassID = "DesktopPaneUI";
98
99 transient DesktopManager desktopManager;
100
101 private transient JInternalFrame selectedFrame = null;
102
103 /**
104 * Indicates that the entire contents of the item being dragged
105 * should appear inside the desktop pane.
106 *
107 * @see #OUTLINE_DRAG_MODE
108 * @see #setDragMode
109 */
110 public static final int LIVE_DRAG_MODE = 0;
111
112 /**
113 * Indicates that an outline only of the item being dragged
114 * should appear inside the desktop pane.
115 *
116 * @see #LIVE_DRAG_MODE
117 * @see #setDragMode
118 */
119 public static final int OUTLINE_DRAG_MODE = 1;
120
121 private int dragMode = LIVE_DRAG_MODE;
122 private boolean dragModeSet = false;
123 private transient List<JInternalFrame> framesCache;
124 private boolean componentOrderCheckingEnabled = true;
125 private boolean componentOrderChanged = false;
126
127 /**
128 * Creates a new <code>JDesktopPane</code>.
129 */
130 public JDesktopPane() {
131 setUIProperty("opaque", Boolean.TRUE);
132 setFocusCycleRoot(true);
133
134 setFocusTraversalPolicy(new LayoutFocusTraversalPolicy() {
135 public Component getDefaultComponent(Container c) {
136 JInternalFrame jifArray[] = getAllFrames();
137 Component comp = null;
138 for (JInternalFrame jif : jifArray) {
139 comp = jif.getFocusTraversalPolicy().getDefaultComponent(jif);
140 if (comp != null) {
141 break;
142 }
143 }
144 return comp;
145 }
146 });
147 updateUI();
148 }
149
150 /**
151 * Returns the L&F object that renders this component.
152 *
153 * @return the <code>DesktopPaneUI</code> object that
154 * renders this component
155 */
156 public DesktopPaneUI getUI() {
157 return (DesktopPaneUI)ui;
158 }
159
160 /**
161 * Sets the L&F object that renders this component.
162 *
163 * @param ui the DesktopPaneUI L&F object
164 * @see UIDefaults#getUI
165 * @beaninfo
166 * bound: true
167 * hidden: true
168 * attribute: visualUpdate true
169 * description: The UI object that implements the Component's LookAndFeel.
170 */
171 public void setUI(DesktopPaneUI ui) {
172 super.setUI(ui);
173 }
174
175 /**
176 * Sets the "dragging style" used by the desktop pane.
177 * You may want to change to one mode or another for
178 * performance or aesthetic reasons.
179 *
180 * @param dragMode the style of drag to use for items in the Desktop
181 *
182 * @see #LIVE_DRAG_MODE
183 * @see #OUTLINE_DRAG_MODE
184 *
185 * @beaninfo
186 * bound: true
187 * description: Dragging style for internal frame children.
188 * enum: LIVE_DRAG_MODE JDesktopPane.LIVE_DRAG_MODE
189 * OUTLINE_DRAG_MODE JDesktopPane.OUTLINE_DRAG_MODE
190 * @since 1.3
191 */
192 public void setDragMode(int dragMode) {
193 int oldDragMode = this.dragMode;
194 this.dragMode = dragMode;
195 firePropertyChange("dragMode", oldDragMode, this.dragMode);
196 dragModeSet = true;
197 }
198
199 /**
200 * Gets the current "dragging style" used by the desktop pane.
201 * @return either <code>Live_DRAG_MODE</code> or
202 * <code>OUTLINE_DRAG_MODE</code>
203 * @see #setDragMode
204 * @since 1.3
205 */
206 public int getDragMode() {
207 return dragMode;
208 }
209
210 /**
211 * Returns the {@code DesktopManger} that handles
212 * desktop-specific UI actions.
213 *
214 * @return the {@code DesktopManger} that handles desktop-specific
215 * UI actions
216 */
217 public DesktopManager getDesktopManager() {
218 return desktopManager;
219 }
220
221 /**
222 * Sets the <code>DesktopManger</code> that will handle
223 * desktop-specific UI actions. This may be overridden by
224 * {@code LookAndFeel}.
225 *
226 * @param d the <code>DesktopManager</code> to use
227 *
228 * @beaninfo
229 * bound: true
230 * description: Desktop manager to handle the internal frames in the
231 * desktop pane.
232 */
233 public void setDesktopManager(DesktopManager d) {
234 DesktopManager oldValue = desktopManager;
235 desktopManager = d;
236 firePropertyChange("desktopManager", oldValue, desktopManager);
237 }
238
239 /**
240 * Notification from the <code>UIManager</code> that the L&F has changed.
241 * Replaces the current UI object with the latest version from the
242 * <code>UIManager</code>.
243 *
244 * @see JComponent#updateUI
245 */
246 public void updateUI() {
247 setUI((DesktopPaneUI)UIManager.getUI(this));
248 }
249
250
251 /**
252 * Returns the name of the L&F class that renders this component.
253 *
254 * @return the string "DesktopPaneUI"
255 * @see JComponent#getUIClassID
256 * @see UIDefaults#getUI
257 */
258 public String getUIClassID() {
259 return uiClassID;
260 }
261
262 /**
263 * Returns all <code>JInternalFrames</code> currently displayed in the
264 * desktop. Returns iconified frames as well as expanded frames.
265 *
266 * @return an array of <code>JInternalFrame</code> objects
267 */
268 public JInternalFrame[] getAllFrames() {
269 return getAllFrames(this).toArray(new JInternalFrame[0]);
270 }
271
272 private static Collection<JInternalFrame> getAllFrames(Container parent) {
273 int i, count;
274 Collection<JInternalFrame> results = new ArrayList<JInternalFrame>();
275 count = parent.getComponentCount();
276 for (i = 0; i < count; i++) {
277 Component next = parent.getComponent(i);
278 if (next instanceof JInternalFrame) {
279 results.add((JInternalFrame) next);
280 } else if (next instanceof JInternalFrame.JDesktopIcon) {
281 JInternalFrame tmp = ((JInternalFrame.JDesktopIcon) next).getInternalFrame();
282 if (tmp != null) {
283 results.add(tmp);
284 }
285 } else if (next instanceof Container) {
286 results.addAll(getAllFrames((Container) next));
287 }
288 }
289 return results;
290 }
291
292 /** Returns the currently active <code>JInternalFrame</code>
293 * in this <code>JDesktopPane</code>, or <code>null</code>
294 * if no <code>JInternalFrame</code> is currently active.
295 *
296 * @return the currently active <code>JInternalFrame</code> or
297 * <code>null</code>
298 * @since 1.3
299 */
300
301 public JInternalFrame getSelectedFrame() {
302 return selectedFrame;
303 }
304
305 /** Sets the currently active <code>JInternalFrame</code>
306 * in this <code>JDesktopPane</code>. This method is used to bridge
307 * the package gap between JDesktopPane and the platform implementation
308 * code and should not be called directly. To visually select the frame
309 * the client must call JInternalFrame.setSelected(true) to activate
310 * the frame.
311 * @see JInternalFrame#setSelected(boolean)
312 *
313 * @param f the internal frame that's currently selected
314 * @since 1.3
315 */
316
317 public void setSelectedFrame(JInternalFrame f) {
318 selectedFrame = f;
319 }
320
321 /**
322 * Returns all <code>JInternalFrames</code> currently displayed in the
323 * specified layer of the desktop. Returns iconified frames as well
324 * expanded frames.
325 *
326 * @param layer an int specifying the desktop layer
327 * @return an array of <code>JInternalFrame</code> objects
328 * @see JLayeredPane
329 */
330 public JInternalFrame[] getAllFramesInLayer(int layer) {
331 Collection<JInternalFrame> allFrames = getAllFrames(this);
332 Iterator<JInternalFrame> iterator = allFrames.iterator();
333 while (iterator.hasNext()) {
334 if (iterator.next().getLayer() != layer) {
335 iterator.remove();
336 }
337 }
338 return allFrames.toArray(new JInternalFrame[0]);
339 }
340
341 private List<JInternalFrame> getFrames() {
342 Component c;
343 Set<ComponentPosition> set = new TreeSet<ComponentPosition>();
344 for (int i = 0; i < getComponentCount(); i++) {
345 c = getComponent(i);
346 if (c instanceof JInternalFrame) {
347 set.add(new ComponentPosition((JInternalFrame)c, getLayer(c),
348 i));
349 }
350 else if (c instanceof JInternalFrame.JDesktopIcon) {
351 c = ((JInternalFrame.JDesktopIcon)c).getInternalFrame();
352 set.add(new ComponentPosition((JInternalFrame)c, getLayer(c),
353 i));
354 }
355 }
356 List<JInternalFrame> frames = new ArrayList<JInternalFrame>(
357 set.size());
358 for (ComponentPosition position : set) {
359 frames.add(position.component);
360 }
361 return frames;
362 }
363
364 private static class ComponentPosition implements
365 Comparable<ComponentPosition> {
366 private final JInternalFrame component;
367 private final int layer;
368 private final int zOrder;
369
370 ComponentPosition(JInternalFrame component, int layer, int zOrder) {
371 this.component = component;
372 this.layer = layer;
373 this.zOrder = zOrder;
374 }
375
376 public int compareTo(ComponentPosition o) {
377 int delta = o.layer - layer;
378 if (delta == 0) {
379 return zOrder - o.zOrder;
380 }
381 return delta;
382 }
383 }
384
385 private JInternalFrame getNextFrame(JInternalFrame f, boolean forward) {
386 verifyFramesCache();
387 if (f == null) {
388 return getTopInternalFrame();
389 }
390 int i = framesCache.indexOf(f);
391 if (i == -1 || framesCache.size() == 1) {
392 /* error */
393 return null;
394 }
395 if (forward) {
396 // navigate to the next frame
397 if (++i == framesCache.size()) {
398 /* wrap */
399 i = 0;
400 }
401 }
402 else {
403 // navigate to the previous frame
404 if (--i == -1) {
405 /* wrap */
406 i = framesCache.size() - 1;
407 }
408 }
409 return framesCache.get(i);
410 }
411
412 JInternalFrame getNextFrame(JInternalFrame f) {
413 return getNextFrame(f, true);
414 }
415
416 private JInternalFrame getTopInternalFrame() {
417 if (framesCache.size() == 0) {
418 return null;
419 }
420 return framesCache.get(0);
421 }
422
423 private void updateFramesCache() {
424 framesCache = getFrames();
425 }
426
427 private void verifyFramesCache() {
428 // If framesCache is dirty, then recreate it.
429 if (componentOrderChanged) {
430 componentOrderChanged = false;
431 updateFramesCache();
432 }
433 }
434
435 /**
436 * {@inheritDoc}
437 */
438 @Override
439 public void remove(Component comp) {
440 super.remove(comp);
441 updateFramesCache();
442 }
443
444 /**
445 * Selects the next <code>JInternalFrame</code> in this desktop pane.
446 *
447 * @param forward a boolean indicating which direction to select in;
448 * <code>true</code> for forward, <code>false</code> for
449 * backward
450 * @return the JInternalFrame that was selected or <code>null</code>
451 * if nothing was selected
452 * @since 1.6
453 */
454 public JInternalFrame selectFrame(boolean forward) {
455 JInternalFrame selectedFrame = getSelectedFrame();
456 JInternalFrame frameToSelect = getNextFrame(selectedFrame, forward);
457 if (frameToSelect == null) {
458 return null;
459 }
460 // Maintain navigation traversal order until an
461 // external stack change, such as a click on a frame.
462 setComponentOrderCheckingEnabled(false);
463 if (forward && selectedFrame != null) {
464 selectedFrame.moveToBack(); // For Windows MDI fidelity.
465 }
466 try { frameToSelect.setSelected(true);
467 } catch (PropertyVetoException pve) {}
468 setComponentOrderCheckingEnabled(true);
469 return frameToSelect;
470 }
471
472 /*
473 * Sets whether component order checking is enabled.
474 * @param enable a boolean value, where <code>true</code> means
475 * a change in component order will cause a change in the keyboard
476 * navigation order.
477 * @since 1.6
478 */
479 void setComponentOrderCheckingEnabled(boolean enable) {
480 componentOrderCheckingEnabled = enable;
481 }
482
483 /**
484 * {@inheritDoc}
485 * @since 1.6
486 */
487 protected void addImpl(Component comp, Object constraints, int index) {
488 super.addImpl(comp, constraints, index);
489 if (componentOrderCheckingEnabled) {
490 if (comp instanceof JInternalFrame ||
491 comp instanceof JInternalFrame.JDesktopIcon) {
492 componentOrderChanged = true;
493 }
494 }
495 }
496
497 /**
498 * {@inheritDoc}
499 * @since 1.6
500 */
501 public void remove(int index) {
502 if (componentOrderCheckingEnabled) {
503 Component comp = getComponent(index);
504 if (comp instanceof JInternalFrame ||
505 comp instanceof JInternalFrame.JDesktopIcon) {
506 componentOrderChanged = true;
507 }
508 }
509 super.remove(index);
510 }
511
512 /**
513 * {@inheritDoc}
514 * @since 1.6
515 */
516 public void removeAll() {
517 if (componentOrderCheckingEnabled) {
518 int count = getComponentCount();
519 for (int i = 0; i < count; i++) {
520 Component comp = getComponent(i);
521 if (comp instanceof JInternalFrame ||
522 comp instanceof JInternalFrame.JDesktopIcon) {
523 componentOrderChanged = true;
524 break;
525 }
526 }
527 }
528 super.removeAll();
529 }
530
531 /**
532 * {@inheritDoc}
533 * @since 1.6
534 */
535 public void setComponentZOrder(Component comp, int index) {
536 super.setComponentZOrder(comp, index);
537 if (componentOrderCheckingEnabled) {
538 if (comp instanceof JInternalFrame ||
539 comp instanceof JInternalFrame.JDesktopIcon) {
540 componentOrderChanged = true;
541 }
542 }
543 }
544
545 /**
546 * See readObject() and writeObject() in JComponent for more
547 * information about serialization in Swing.
548 */
549 private void writeObject(ObjectOutputStream s) throws IOException {
550 s.defaultWriteObject();
551 if (getUIClassID().equals(uiClassID)) {
552 byte count = JComponent.getWriteObjCounter(this);
553 JComponent.setWriteObjCounter(this, --count);
554 if (count == 0 && ui != null) {
555 ui.installUI(this);
556 }
557 }
558 }
559
560 void setUIProperty(String propertyName, Object value) {
561 if (propertyName == "dragMode") {
562 if (!dragModeSet) {
563 setDragMode(((Integer)value).intValue());
564 dragModeSet = false;
565 }
566 } else {
567 super.setUIProperty(propertyName, value);
568 }
569 }
570
571 /**
572 * Returns a string representation of this <code>JDesktopPane</code>.
573 * This method is intended to be used only for debugging purposes, and the
574 * content and format of the returned string may vary between
575 * implementations. The returned string may be empty but may not
576 * be <code>null</code>.
577 *
578 * @return a string representation of this <code>JDesktopPane</code>
579 */
580 protected String paramString() {
581 String desktopManagerString = (desktopManager != null ?
582 desktopManager.toString() : "");
583
584 return super.paramString() +
585 ",desktopManager=" + desktopManagerString;
586 }
587
588 /////////////////
589 // Accessibility support
590 ////////////////
591
592 /**
593 * Gets the <code>AccessibleContext</code> associated with this
594 * <code>JDesktopPane</code>. For desktop panes, the
595 * <code>AccessibleContext</code> takes the form of an
596 * <code>AccessibleJDesktopPane</code>.
597 * A new <code>AccessibleJDesktopPane</code> instance is created if necessary.
598 *
599 * @return an <code>AccessibleJDesktopPane</code> that serves as the
600 * <code>AccessibleContext</code> of this <code>JDesktopPane</code>
601 */
602 public AccessibleContext getAccessibleContext() {
603 if (accessibleContext == null) {
604 accessibleContext = new AccessibleJDesktopPane();
605 }
606 return accessibleContext;
607 }
608
609 /**
610 * This class implements accessibility support for the
611 * <code>JDesktopPane</code> class. It provides an implementation of the
612 * Java Accessibility API appropriate to desktop pane user-interface
613 * elements.
614 * <p>
615 * <strong>Warning:</strong>
616 * Serialized objects of this class will not be compatible with
617 * future Swing releases. The current serialization support is
618 * appropriate for short term storage or RMI between applications running
619 * the same version of Swing. As of 1.4, support for long term storage
620 * of all JavaBeans™
621 * has been added to the <code>java.beans</code> package.
622 * Please see {@link java.beans.XMLEncoder}.
623 */
624 @SuppressWarnings("serial") // Same-version serialization only
625 protected class AccessibleJDesktopPane extends AccessibleJComponent {
626
627 /**
628 * Get the role of this object.
629 *
630 * @return an instance of AccessibleRole describing the role of the
631 * object
632 * @see AccessibleRole
633 */
634 public AccessibleRole getAccessibleRole() {
635 return AccessibleRole.DESKTOP_PANE;
636 }
637 }
638 }