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