001 /* JSlider.java --
002 Copyright (C) 2002, 2004, 2005, 2006, Free Software Foundation, Inc.
003
004 This file is part of GNU Classpath.
005
006 GNU Classpath is free software; you can redistribute it and/or modify
007 it under the terms of the GNU General Public License as published by
008 the Free Software Foundation; either version 2, or (at your option)
009 any later version.
010
011 GNU Classpath is distributed in the hope that it will be useful, but
012 WITHOUT ANY WARRANTY; without even the implied warranty of
013 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
014 General Public License for more details.
015
016 You should have received a copy of the GNU General Public License
017 along with GNU Classpath; see the file COPYING. If not, write to the
018 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019 02110-1301 USA.
020
021 Linking this library statically or dynamically with other modules is
022 making a combined work based on this library. Thus, the terms and
023 conditions of the GNU General Public License cover the whole
024 combination.
025
026 As a special exception, the copyright holders of this library give you
027 permission to link this library with independent modules to produce an
028 executable, regardless of the license terms of these independent
029 modules, and to copy and distribute the resulting executable under
030 terms of your choice, provided that you also meet, for each linked
031 independent module, the terms and conditions of the license of that
032 module. An independent module is a module which is not derived from
033 or based on this library. If you modify this library, you may extend
034 this exception to your version of the library, but you are not
035 obligated to do so. If you do not wish to do so, delete this
036 exception statement from your version. */
037
038
039 package javax.swing;
040
041 import java.awt.MenuContainer;
042 import java.awt.image.ImageObserver;
043 import java.beans.PropertyChangeEvent;
044 import java.io.Serializable;
045 import java.util.Dictionary;
046 import java.util.Enumeration;
047 import java.util.Hashtable;
048
049 import javax.accessibility.Accessible;
050 import javax.accessibility.AccessibleContext;
051 import javax.accessibility.AccessibleRole;
052 import javax.accessibility.AccessibleState;
053 import javax.accessibility.AccessibleStateSet;
054 import javax.accessibility.AccessibleValue;
055 import javax.swing.event.ChangeEvent;
056 import javax.swing.event.ChangeListener;
057 import javax.swing.plaf.SliderUI;
058 import javax.swing.plaf.UIResource;
059
060 /**
061 * A visual component that allows selection of a value within a
062 * range by adjusting a thumb in a track. The values for the minimum,
063 * maximum, extent and value are stored in a {@link
064 * DefaultBoundedRangeModel}.
065 * <p>
066 * A <code>JSlider</code> component has the following properties:
067 * </p>
068 *
069 * <table>
070 * <tr><th> Property </th><th> Stored in </th><th> Bound? </th></tr>
071 * <tr><td> extent </td><td> model </td><td> no </td></tr>
072 * <tr><td> inverted </td><td> slider </td><td> yes </td></tr>
073 * <tr><td> labelTable </td><td> slider </td><td> yes </td></tr>
074 * <tr><td> majorTickSpacing </td><td> slider </td><td> yes </td></tr>
075 * <tr><td> maximum </td><td> model </td><td> yes </td></tr>
076 * <tr><td> minimum </td><td> model </td><td> yes </td></tr>
077 * <tr><td> minorTickSpacing </td><td> slider </td><td> yes </td></tr>
078 * <tr><td> model </td><td> slider </td><td> yes </td></tr>
079 * <tr><td> orientation </td><td> slider </td><td> yes </td></tr>
080 * <tr><td> paintLabels </td><td> slider </td><td> yes </td></tr>
081 * <tr><td> paintTicks </td><td> slider </td><td> yes </td></tr>
082 * <tr><td> snapToTicks </td><td> slider </td><td> yes </td></tr>
083 * <tr><td> value </td><td> model </td><td> no </td></tr>
084 * <tr><td> valueIsAdjusting </td><td> model </td><td> no </td></tr>
085 * </table>
086 *
087 * <p>
088 * The various behavioural aspects of these properties follows:
089 * </p>
090 *
091 * <ul>
092 * <li>
093 * When a non-bound property stored in the slider changes, the slider fires
094 * a {@link ChangeEvent} to its change listeners.
095 * </li>
096 * <li>
097 * When a bound property stored in the slider changes, the slider fires a
098 * {@link PropertyChangeEvent} to its property change listeners.
099 * </li>
100 * <li>
101 * If any of the model's properties change, it fires a {@link ChangeEvent} to
102 * its listeners, which include the slider.
103 * </li>
104 * <li>
105 * If the slider receives a {@link ChangeEvent} from its model, it will
106 * propagate the event to its own change listeners, with the event's "source"
107 * property set to refer to the slider, rather than the model.
108 * </li>
109 * </ul>
110 */
111 public class JSlider extends JComponent implements SwingConstants, Accessible,
112 ImageObserver,
113 MenuContainer, Serializable
114 {
115
116 /**
117 * A little testing shows that the reference implementation creates
118 * labels from a class named LabelUIResource.
119 */
120 private class LabelUIResource
121 extends JLabel
122 implements UIResource
123 {
124 LabelUIResource(String text, int align)
125 {
126 super(text, align);
127 setName("Slider.label");
128 }
129 }
130
131 private static final long serialVersionUID = -1441275936141218479L;
132
133 /**
134 * Provides the accessibility features for the <code>JSlider</code>
135 * component.
136 */
137 protected class AccessibleJSlider extends JComponent.AccessibleJComponent
138 implements AccessibleValue
139 {
140 private static final long serialVersionUID = -6301740148041106789L;
141
142 /**
143 * Creates a new <code>AccessibleJSlider</code> instance.
144 */
145 protected AccessibleJSlider()
146 {
147 // Nothing to do here.
148 }
149
150 /**
151 * Returns a set containing the current state of the {@link JSlider}
152 * component.
153 *
154 * @return The accessible state set.
155 */
156 public AccessibleStateSet getAccessibleStateSet()
157 {
158 AccessibleStateSet result = super.getAccessibleStateSet();
159 if (orientation == JSlider.HORIZONTAL)
160 result.add(AccessibleState.HORIZONTAL);
161 else if (orientation == JSlider.VERTICAL)
162 result.add(AccessibleState.VERTICAL);
163 return result;
164 }
165
166 /**
167 * Returns the accessible role for the <code>JSlider</code> component.
168 *
169 * @return {@link AccessibleRole#SLIDER}.
170 */
171 public AccessibleRole getAccessibleRole()
172 {
173 return AccessibleRole.SLIDER;
174 }
175
176 /**
177 * Returns an object that provides access to the current, minimum and
178 * maximum values for the {@link JSlider}. Since this class implements
179 * {@link AccessibleValue}, it returns itself.
180 *
181 * @return The accessible value.
182 */
183 public AccessibleValue getAccessibleValue()
184 {
185 return this;
186 }
187
188 /**
189 * Returns the current value of the {@link JSlider} component, as an
190 * {@link Integer}.
191 *
192 * @return The current value of the {@link JSlider} component.
193 */
194 public Number getCurrentAccessibleValue()
195 {
196 return new Integer(getValue());
197 }
198
199 /**
200 * Sets the current value of the {@link JSlider} component and sends a
201 * {@link PropertyChangeEvent} (with the property name
202 * {@link AccessibleContext#ACCESSIBLE_VALUE_PROPERTY}) to all registered
203 * listeners. If the supplied value is <code>null</code>, this method
204 * does nothing and returns <code>false</code>.
205 *
206 * @param value the new slider value (<code>null</code> permitted).
207 *
208 * @return <code>true</code> if the slider value is updated, and
209 * <code>false</code> otherwise.
210 */
211 public boolean setCurrentAccessibleValue(Number value)
212 {
213 if (value == null)
214 return false;
215 Number oldValue = getCurrentAccessibleValue();
216 setValue(value.intValue());
217 firePropertyChange(AccessibleContext.ACCESSIBLE_VALUE_PROPERTY, oldValue,
218 new Integer(getValue()));
219 return true;
220 }
221
222 /**
223 * Returns the minimum value of the {@link JSlider} component, as an
224 * {@link Integer}.
225 *
226 * @return The minimum value of the {@link JSlider} component.
227 */
228 public Number getMinimumAccessibleValue()
229 {
230 return new Integer(getMinimum());
231 }
232
233 /**
234 * Returns the maximum value of the {@link JSlider} component, as an
235 * {@link Integer}.
236 *
237 * @return The maximum value of the {@link JSlider} component.
238 */
239 public Number getMaximumAccessibleValue()
240 {
241 return new Integer(getMaximum());
242 }
243 }
244
245 /** Whether or not this slider paints its ticks. */
246 private transient boolean paintTicks;
247
248 /** Whether or not this slider paints its track. */
249 private transient boolean paintTrack = true;
250
251 /** Whether or not this slider paints its labels. */
252 private transient boolean paintLabels;
253
254 /**
255 * A dictionary of (Integer, Component) pairs where each Component is a
256 * JLabel and the Integer determines where the label will be painted.
257 */
258 private transient Dictionary labelTable;
259
260 /** The model used to store the slider's range and current value. */
261 protected BoundedRangeModel sliderModel;
262
263 /** The space/distance between major ticks. */
264 protected int majorTickSpacing;
265
266 /** The space/distance between minor ticks. */
267 protected int minorTickSpacing;
268
269 /** Whether the slider snaps its values to ticks. */
270 protected boolean snapToTicks;
271
272 /** The orientation (horizontal or vertical) of the slider. */
273 protected int orientation = HORIZONTAL;
274
275 /** Whether the slider is inverted. */
276 private transient boolean isInverted;
277
278 /**
279 * The listener that monitors the slider's model and forwards events to the
280 * slider's listeners (see <code>createChangeListener()</code>).
281 */
282 protected ChangeListener changeListener;
283
284 /** The change event that is passed to all listeners of this slider. */
285 protected transient ChangeEvent changeEvent;
286
287 /**
288 * Creates a new horizontal <code>JSlider</code> instance with a minimum of
289 * 0, a maximum of 100, and a value of 50.
290 */
291 public JSlider()
292 {
293 this(HORIZONTAL, 0, 100, 50);
294 }
295
296 /**
297 * Creates a new <code>JSlider</code> instance with the given orientation
298 * and a minimum of 0, a maximum of 100, and a value of 50.
299 *
300 * @param orientation The orientation of the slider ({@link #HORIZONTAL} or
301 * {@link #VERTICAL}).
302 *
303 * @throws IllegalArgumentException if <code>orientation</code> is not one of
304 * the specified values.
305 */
306 public JSlider(int orientation)
307 {
308 this(orientation, 0, 100, 50);
309 }
310
311 /**
312 * Creates a new horizontal <code>JSlider</code> instance with the given
313 * maximum and minimum and a value that is halfway between the minimum and the
314 * maximum.
315 *
316 * @param minimum The minimum value.
317 * @param maximum The maximum value.
318 *
319 * @throws IllegalArgumentException if <code>minimum</code> is greater than
320 * <code>maximum</code>.
321 */
322 public JSlider(int minimum, int maximum)
323 {
324 this(HORIZONTAL, minimum, maximum, (maximum + minimum) / 2);
325 }
326
327 /**
328 * Creates a new horizontal <code>JSlider</code> instance with the given
329 * minimum, maximum, and value.
330 *
331 * @param minimum The minimum value.
332 * @param maximum The maximum value.
333 * @param value The initial value.
334 *
335 * @throws IllegalArgumentException if <code>value</code> is not in the
336 * specified range.
337 * @throws IllegalArgumentException if <code>minimum</code> is greater than
338 * <code>maximum</code>.
339 */
340 public JSlider(int minimum, int maximum, int value)
341 {
342 this(HORIZONTAL, minimum, maximum, value);
343 }
344
345 /**
346 * Creates a new <code>JSlider</code> instance with the given orientation,
347 * minimum, maximum, and value.
348 *
349 * @param orientation The orientation of the slider ({@link #HORIZONTAL} or
350 * {@link #VERTICAL}).
351 * @param minimum The minimum value of the JSlider.
352 * @param maximum The maximum value of the JSlider.
353 * @param value The initial value of the JSlider.
354 *
355 * @throws IllegalArgumentException if <code>orientation</code> is not one of
356 * the specified values.
357 * @throws IllegalArgumentException if <code>value</code> is not in the
358 * specified range.
359 * @throws IllegalArgumentException if <code>minimum</code> is greater than
360 * <code>maximum</code>.
361 */
362 public JSlider(int orientation, int minimum, int maximum, int value)
363 {
364 sliderModel = new DefaultBoundedRangeModel(value, 0, minimum, maximum);
365 if (orientation != HORIZONTAL && orientation != VERTICAL)
366 throw new IllegalArgumentException(orientation
367 + " is not a legal orientation");
368 this.orientation = orientation;
369 changeListener = createChangeListener();
370 sliderModel.addChangeListener(changeListener);
371 updateUI();
372 }
373
374 /**
375 * Creates a new horizontal <code>JSlider</code> instance with the given
376 * model.
377 *
378 * @param model The model (<code>null</code> not permitted).
379 *
380 * @throws NullPointerException if <code>model</code> is <code>null</code>.
381 */
382 public JSlider(BoundedRangeModel model)
383 {
384 sliderModel = model;
385 changeListener = createChangeListener();
386 sliderModel.addChangeListener(changeListener);
387 updateUI();
388 }
389
390 /**
391 * Returns the slider's value (from the slider's model).
392 *
393 * @return The value of the slider.
394 *
395 * @see #setValue(int)
396 */
397 public int getValue()
398 {
399 return sliderModel.getValue();
400 }
401
402 /**
403 * Sets the slider's value and sends a {@link ChangeEvent} to all
404 * registered listeners. Note that the model will fire a change event to all
405 * of its registered listeners first (with the model as the event source) and
406 * then the slider will fire another change event to all of its registered
407 * listeners (this time with the slider as the event source).
408 *
409 * @param value the new value.
410 *
411 * @see #getValue()
412 */
413 public void setValue(int value)
414 {
415 sliderModel.setValue(value);
416 }
417
418 /**
419 * Returns the slider's UI delegate.
420 *
421 * @return The slider's UI delegate.
422 */
423 public SliderUI getUI()
424 {
425 return (SliderUI) ui;
426 }
427
428 /**
429 * Sets the slider's UI delegate.
430 *
431 * @param ui the UI delegate.
432 */
433 public void setUI(SliderUI ui)
434 {
435 super.setUI(ui);
436 }
437
438 /**
439 * Sets this slider's UI delegate to the default (obtained from the
440 * {@link UIManager}) for the current look and feel.
441 */
442 public void updateUI()
443 {
444 updateLabelUIs();
445 setUI((SliderUI) UIManager.getUI(this));
446 }
447
448 /**
449 * Returns the suffix (<code>"SliderUI"</code> in this case) used to
450 * determine the class name for a UI delegate that can provide the look and
451 * feel for a <code>JSlider</code>.
452 *
453 * @return <code>"SliderUI"</code>.
454 */
455 public String getUIClassID()
456 {
457 return "SliderUI";
458 }
459
460 /**
461 * Creates a {@link ChangeListener} that is added to the slider's model and
462 * forwards change events generated by the model to the listeners that are
463 * registered with the <code>JSlider</code> (by calling the
464 * {@link #fireStateChanged} method).
465 *
466 * @return A new listener.
467 */
468 protected ChangeListener createChangeListener()
469 {
470 return new ChangeListener()
471 {
472 public void stateChanged(ChangeEvent ce)
473 {
474 // No need to trigger a repaint since the UI listens to the model
475 // as well. All we need to do is pass on the stateChanged event
476 // to our listeners.
477 fireStateChanged();
478 }
479 };
480 }
481
482 /**
483 * Registers a listener with the slider so that it will receive
484 * {@link ChangeEvent} notifications. Note that change events generated
485 * by the slider's model will be forwarded automatically to the slider's
486 * listeners.
487 *
488 * @param listener the listener to register.
489 *
490 * @see #removeChangeListener(ChangeListener)
491 */
492 public void addChangeListener(ChangeListener listener)
493 {
494 listenerList.add(ChangeListener.class, listener);
495 }
496
497 /**
498 * Removes a listener from this slider so that it will no longer receive
499 * {@link ChangeEvent} notifications from the slider.
500 *
501 * @param listener The listener to remove.
502 *
503 * @see #addChangeListener(ChangeListener)
504 */
505 public void removeChangeListener(ChangeListener listener)
506 {
507 listenerList.remove(ChangeListener.class, listener);
508 }
509
510 /**
511 * Sends a {@link ChangeEvent} to all registered listeners, with this slider
512 * as the source.
513 */
514 protected void fireStateChanged()
515 {
516 Object[] changeListeners = listenerList.getListenerList();
517 if (changeEvent == null)
518 changeEvent = new ChangeEvent(this);
519 for (int i = changeListeners.length - 2; i >= 0; i -= 2)
520 {
521 if (changeListeners[i] == ChangeListener.class)
522 ((ChangeListener) changeListeners[i + 1]).stateChanged(changeEvent);
523 }
524 }
525
526 /**
527 * Returns an array containing all the {@link ChangeListener} instances
528 * registered with this slider. If no listeners are registered, this method
529 * returns an empty array.
530 *
531 * @return An array array containing all the {@link ChangeListener} instances
532 * registered with this slider (possibly empty, but never
533 * <code>null</code>).
534 */
535 public ChangeListener[] getChangeListeners()
536 {
537 return (ChangeListener[]) listenerList.getListeners(ChangeListener.class);
538 }
539
540 /**
541 * Returns the slider's model, which stores the minimum, maximum and current
542 * values.
543 *
544 * @return The slider's model.
545 *
546 * @see #setModel(BoundedRangeModel)
547 */
548 public BoundedRangeModel getModel()
549 {
550 return sliderModel;
551 }
552
553 /**
554 * Sets the slider's model and sends a {@link PropertyChangeEvent} (with the
555 * property name "model") to all registered listeners. The change listener
556 * that the slider registered with the original model is removed and added
557 * to the new model (this ensures that {@link ChangeEvent} notifications
558 * generated by the model are automatically forwarded to listeners that are
559 * registered with the slider).
560 *
561 * @param model The model to use with the slider.
562 *
563 * @see #getModel()
564 */
565 public void setModel(BoundedRangeModel model)
566 {
567 // I didn't do the null pointer check on purpose.
568 // If you try it with Sun's, it'll go ahead and set it to null
569 // and bork the next time it tries to access the model.
570 if (model != sliderModel)
571 {
572 BoundedRangeModel oldModel = sliderModel;
573 sliderModel = model;
574 oldModel.removeChangeListener(changeListener);
575 sliderModel.addChangeListener(changeListener);
576 firePropertyChange("model", oldModel, sliderModel);
577 }
578 }
579
580 /**
581 * Returns the minimum value of the slider (from the slider's model).
582 *
583 * @return The minimum value of the slider.
584 *
585 * @see #setMinimum(int)
586 */
587 public int getMinimum()
588 {
589 return sliderModel.getMinimum();
590 }
591
592 /**
593 * Sets the minimum value of the slider and fires a
594 * {@link PropertyChangeEvent} (with the property name "minimum") to all
595 * registered listeners. Note that:
596 * <p>
597 * <ul>
598 * <li>the minimum value is stored in the slider's model (see
599 * {@link #getModel()});</li>
600 * <li>in addition to the property change event, the slider also fires a
601 * {@link ChangeEvent}.</li>
602 * </ul>
603 *
604 * @param minimum The minimum value of the slider.
605 *
606 * @see #getMinimum()
607 */
608 public void setMinimum(int minimum)
609 {
610 int old = sliderModel.getMinimum();
611 sliderModel.setMinimum(minimum);
612 if (minimum != old)
613 firePropertyChange("minimum", old, minimum);
614 }
615
616 /**
617 * Returns the slider's maximum value (obtained from the slider's model).
618 *
619 * @return The maximum value of the slider.
620 *
621 * @see #setMaximum(int)
622 */
623 public int getMaximum()
624 {
625 return sliderModel.getMaximum();
626 }
627
628 /**
629 * Sets the maximum value of the slider and fires a
630 * {@link PropertyChangeEvent} (with the property name "maximum") to all
631 * registered listeners. Note that:
632 * <p>
633 * <ul>
634 * <li>the maximum value is stored in the slider's model (see
635 * {@link #getModel()});</li>
636 * <li>in addition to the property change event, the slider also fires a
637 * {@link ChangeEvent}.</li>
638 * </ul>
639 *
640 * @param maximum The maximum value of the slider.
641 *
642 * @see #getMaximum()
643 */
644 public void setMaximum(int maximum)
645 {
646 int old = sliderModel.getMaximum();
647 sliderModel.setMaximum(maximum);
648 if (maximum != old)
649 firePropertyChange("maximum", old, maximum);
650 }
651
652 /**
653 * Returns the <code>valueIsAdjusting</code> flag from the slider's model.
654 *
655 * @return The <code>valueIsAdjusting</code> flag from the slider's model.
656 *
657 * @see #setValueIsAdjusting(boolean)
658 */
659 public boolean getValueIsAdjusting()
660 {
661 return sliderModel.getValueIsAdjusting();
662 }
663
664 /**
665 * Sets the <code>valueIsAdjusting</code> flag in the slider's model, and
666 * sends a {@link ChangeEvent} to all registered listeners.
667 *
668 * @param adjusting the new flag value.
669 *
670 * @see #getValueIsAdjusting()
671 */
672 public void setValueIsAdjusting(boolean adjusting)
673 {
674 sliderModel.setValueIsAdjusting(adjusting);
675 }
676
677 /**
678 * Returns the slider's extent value, obtained from the slider's model.
679 *
680 * @return The extent value.
681 *
682 * @see #setExtent(int)
683 */
684 public int getExtent()
685 {
686 return sliderModel.getExtent();
687 }
688
689 /**
690 * Sets the slider's extent value and sends a {@link ChangeEvent} to all
691 * registered listeners. Note that the model will fire a change event to all
692 * of its registered listeners first (with the model as the event source) and
693 * then the slider will fire another change event to all of its registered
694 * listeners (this time with the slider as the event source).
695 *
696 * @param extent The extent value for this slider.
697 *
698 * @see #getExtent()
699 */
700 public void setExtent(int extent)
701 {
702 sliderModel.setExtent(extent);
703 }
704
705 /**
706 * Returns the orientation of the slider, either {@link JSlider#HORIZONTAL}
707 * or {@link JSlider#VERTICAL}.
708 *
709 * @return The orientation of the slider.
710 *
711 * @see #setOrientation(int)
712 */
713 public int getOrientation()
714 {
715 return orientation;
716 }
717
718 /**
719 * Sets the orientation for the slider and sends a
720 * {@link PropertyChangeEvent} (with the property name "orientation") to all
721 * registered listeners.
722 *
723 * @param orientation the orientation (one of {@link JSlider#HORIZONTAL} or
724 * {@link JSlider#VERTICAL}).
725 *
726 * @throws IllegalArgumentException if <code>orientation</code> is not one of
727 * the permitted values.
728 *
729 * @see #getOrientation()
730 */
731 public void setOrientation(int orientation)
732 {
733 if (orientation != VERTICAL && orientation != HORIZONTAL)
734 throw new IllegalArgumentException(
735 "orientation must be one of: VERTICAL, HORIZONTAL");
736 if (orientation != this.orientation)
737 {
738 int oldOrientation = this.orientation;
739 this.orientation = orientation;
740 firePropertyChange("orientation", oldOrientation, this.orientation);
741 revalidate();
742 }
743 }
744
745 /**
746 * Returns the label table for the slider.
747 *
748 * @return The label table for the slider (possibly <code>null</code>).
749 *
750 * @see #setLabelTable(Dictionary)
751 */
752 public Dictionary getLabelTable()
753 {
754 return labelTable;
755 }
756
757 /**
758 * Sets the table of labels for the slider and sends a
759 * {@link PropertyChangeEvent} (with the property name "labelTable") to all
760 * registered listeners.
761 *
762 * @param table the table of labels (<code>null</code> permitted).
763 *
764 * @see #getLabelTable()
765 */
766 public void setLabelTable(Dictionary table)
767 {
768 if (table != labelTable)
769 {
770 Dictionary oldTable = labelTable;
771 labelTable = table;
772 updateLabelUIs();
773 firePropertyChange("labelTable", oldTable, labelTable);
774 revalidate();
775 repaint();
776 }
777 }
778
779 /**
780 * Resets the UI delegates for the labels in the <code>labelTable</code> to
781 * the default for the current look and feel.
782 */
783 protected void updateLabelUIs()
784 {
785 if (labelTable != null)
786 {
787 for (Enumeration list = labelTable.elements(); list.hasMoreElements();)
788 {
789 Object o = list.nextElement();
790 if (o instanceof JComponent)
791 {
792 JComponent jc = (JComponent) o;
793 jc.updateUI();
794 jc.setSize(jc.getPreferredSize());
795 }
796 }
797 }
798 }
799
800 /**
801 * Creates a hashtable of <code>(Integer, JLabel)</code> pairs that can be
802 * used as a label table for this slider. The labels will start from the
803 * slider's minimum and increase by the increment. Each label will have a text
804 * string indicating its integer value.
805 *
806 * @param increment The increment between labels (must be > 0).
807 *
808 * @return A hashtable containing the labels.
809 *
810 * @throws IllegalArgumentException if <code>increment</code> is not greater
811 * than zero.
812 */
813 public Hashtable createStandardLabels(int increment)
814 {
815 return createStandardLabels(increment, sliderModel.getMinimum());
816 }
817
818 /**
819 * Creates a hashtable of <code>(Integer, JLabel)</code> pairs that can be
820 * used as a label table for this slider. The labels will start from the
821 * given start value and increase by the increment. Each label will have a
822 * text string indicating its integer value.
823 *
824 * @param increment The increment between labels (must be > 0).
825 * @param start The value to start from.
826 *
827 * @return A hashtable with the labels and their keys.
828 *
829 * @throws IllegalArgumentException if <code>increment</code> is not greater
830 * than zero, or <code>start</code> is not within the range of the
831 * model.
832 */
833 public Hashtable createStandardLabels(int increment, int start)
834 {
835 if (increment <= 0)
836 throw new IllegalArgumentException("Requires 'increment' > 0.");
837 if (start < getMinimum() || start > getMaximum())
838 throw new IllegalArgumentException("The 'start' value is out of range.");
839 Hashtable table = new Hashtable();
840 int max = getMaximum();
841 for (int i = start; i <= max; i += increment)
842 {
843 LabelUIResource label = new LabelUIResource(String.valueOf(i),
844 JLabel.CENTER);
845 table.put(new Integer(i), label);
846 }
847 return table;
848 }
849
850 /**
851 * Returns the flag that controls whether or not the value scale for the
852 * slider is inverted (the default value is <code>false</code>).
853 *
854 * @return The flag that controls whether or not the value scale for the
855 * slider is inverted.
856 *
857 * @see #setInverted(boolean)
858 */
859 public boolean getInverted()
860 {
861 return isInverted;
862 }
863
864 /**
865 * Sets the flag that controls whether or not the value scale for the
866 * slider is inverted and, if the new flag value is different to the old flag
867 * value, sends a {@link PropertyChangeEvent} to all registered listeners.
868 * Typically, a horizontal slider will display a scale that increases from
869 * left to right, but this is reversed if the 'inverted' flag is set to
870 * <code>true</code>. Similarly, a vertical slider will display a scale that
871 * increases from bottom to top, and this is reversed if the 'inverted' flag
872 * is set to <code>true</code>.
873 *
874 * @param inverted the new flag value.
875 *
876 * @see #getInverted()
877 */
878 public void setInverted(boolean inverted)
879 {
880 if (isInverted != inverted)
881 {
882 boolean oldInverted = isInverted;
883 isInverted = inverted;
884 firePropertyChange("inverted", oldInverted, isInverted);
885 repaint();
886 }
887 }
888
889 /**
890 * Returns the distance between major tick marks along the slider's value
891 * scale.
892 *
893 * @return The amount of units between each major tick mark.
894 *
895 * @see #setMajorTickSpacing(int)
896 */
897 public int getMajorTickSpacing()
898 {
899 return majorTickSpacing;
900 }
901
902 /**
903 * Sets the distance between major tick marks along the slider's value scale,
904 * and sends a {@link PropertyChangeEvent} (with the property name
905 * "majorTickSpacing") to all registered listeners.
906 *
907 * @param spacing the distance between major tick marks.
908 *
909 * @see #getMajorTickSpacing()
910 */
911 public void setMajorTickSpacing(int spacing)
912 {
913 if (majorTickSpacing != spacing)
914 {
915 int oldSpacing = majorTickSpacing;
916 majorTickSpacing = spacing;
917 if (labelTable == null && majorTickSpacing > 0 && getPaintLabels())
918 setLabelTable(createStandardLabels(majorTickSpacing));
919 firePropertyChange("majorTickSpacing", oldSpacing, majorTickSpacing);
920 if (getPaintTicks())
921 repaint();
922 }
923 }
924
925 /**
926 * Returns the distance between minor tick marks along the slider's value
927 * scale.
928 *
929 * @return The distance between minor tick marks along the slider's value
930 * scale.
931 *
932 * @see #setMinorTickSpacing(int)
933 */
934 public int getMinorTickSpacing()
935 {
936 return minorTickSpacing;
937 }
938
939 /**
940 * Sets the distance between minor tick marks along the slider's value scale,
941 * and sends a {@link PropertyChangeEvent} (with the property name
942 * "minorTickSpacing") to all registered listeners.
943 *
944 * @param spacing the distance between minor tick marks.
945 *
946 * @see #getMinorTickSpacing()
947 */
948 public void setMinorTickSpacing(int spacing)
949 {
950 if (minorTickSpacing != spacing)
951 {
952 int oldSpacing = minorTickSpacing;
953 minorTickSpacing = spacing;
954 firePropertyChange("minorTickSpacing", oldSpacing, minorTickSpacing);
955 if (getPaintTicks())
956 repaint();
957 }
958 }
959
960 /**
961 * Returns the flag that controls whether the slider thumb will snap to ticks.
962 * Sliders that snap to ticks will automatically move the thumb to the
963 * nearest tick mark.
964 *
965 * @return <code>true</code> if the slider thumb automatically.
966 *
967 * @see #setSnapToTicks(boolean)
968 */
969 public boolean getSnapToTicks()
970 {
971 return snapToTicks;
972 }
973
974 /**
975 * Sets the flag that controls whether the slider thumb will snap to ticks
976 * and sends a {@link PropertyChangeEvent} (with the property name
977 * 'snapToTicks') to all registered listeners. Sliders that snap to ticks
978 * will automatically move the thumb to the nearest tick mark.
979 *
980 * @param snap the new flag value.
981 *
982 * @see #getSnapToTicks()
983 */
984 public void setSnapToTicks(boolean snap)
985 {
986 if (snap != snapToTicks)
987 {
988 snapToTicks = snap;
989 firePropertyChange("snapToTicks", !snap, snap);
990 }
991 }
992
993 /**
994 * Returns the flag that controls whether or not tick marks are painted along
995 * the slider's value scale.
996 *
997 * @return <code>true</code> if tick marks should be painted, and
998 * <code>false</code> if tick marks should not be painted.
999 *
1000 * @see #setPaintTicks(boolean)
1001 */
1002 public boolean getPaintTicks()
1003 {
1004 return paintTicks;
1005 }
1006
1007 /**
1008 * Sets the flag that controls whether or not tick marks are painted along
1009 * the slider's value scale, and sends a {@link PropertyChangeEvent} (with
1010 * the property name "paintTicks") to all registered listeners. In
1011 * addition to setting this property to <code>true</code>, one or both of the
1012 * minor tick spacing and major tick spacing attributes must be set to a
1013 * value greater than 0 in order for ticks to be painted.
1014 *
1015 * @param paint Whether ticks will be painted.
1016 *
1017 * @see #getPaintTicks()
1018 */
1019 public void setPaintTicks(boolean paint)
1020 {
1021 if (paint != paintTicks)
1022 {
1023 boolean oldPaintTicks = paintTicks;
1024 paintTicks = paint;
1025 firePropertyChange("paintTicks", oldPaintTicks, paintTicks);
1026 revalidate();
1027 repaint();
1028 }
1029 }
1030
1031 /**
1032 * Returns the flag that controls whether or not the track is painted.
1033 *
1034 * @return Whether the track will be painted.
1035 *
1036 * @see #setPaintTrack(boolean)
1037 */
1038 public boolean getPaintTrack()
1039 {
1040 return paintTrack;
1041 }
1042
1043 /**
1044 * Sets the flag that controls whether or not the track is painted, and
1045 * sends a {@link PropertyChangeEvent} (for the "paintTrack" property) to all
1046 * registered listeners.
1047 *
1048 * @param paint Whether the track will be painted.
1049 *
1050 * @see #getPaintTrack()
1051 */
1052 public void setPaintTrack(boolean paint)
1053 {
1054 if (paintTrack != paint)
1055 {
1056 paintTrack = paint;
1057 firePropertyChange("paintTrack", !paint, paint);
1058 repaint();
1059 }
1060 }
1061
1062 /**
1063 * Returns the flag that controls whether or not labels are painted for the
1064 * tick marks along the slider.
1065 *
1066 * @return Whether labels will be painted.
1067 *
1068 * @see #setPaintLabels(boolean)
1069 */
1070 public boolean getPaintLabels()
1071 {
1072 return paintLabels;
1073 }
1074
1075 /**
1076 * Sets the flag that controls whether or not labels are painted for the
1077 * tick marks along the slider and sends a {@link PropertyChangeEvent} (with
1078 * the property name "paintLabels") to all registered listeners.
1079 *
1080 * @param paint Whether labels will be painted.
1081 *
1082 * @see #getPaintLabels()
1083 */
1084 public void setPaintLabels(boolean paint)
1085 {
1086 if (paint != paintLabels)
1087 {
1088 paintLabels = paint;
1089 if (paint && majorTickSpacing > 0 && labelTable == null)
1090 setLabelTable(createStandardLabels(majorTickSpacing));
1091 firePropertyChange("paintLabels", !paint, paint);
1092 revalidate();
1093 repaint();
1094 }
1095 }
1096
1097 /**
1098 * Returns an implementation-dependent string describing the attributes of
1099 * this <code>JSlider</code>.
1100 *
1101 * @return A string describing the attributes of this <code>JSlider</code>
1102 * (never <code>null</code>).
1103 */
1104 protected String paramString()
1105 {
1106 String superParamStr = super.paramString();
1107 StringBuffer sb = new StringBuffer();
1108 sb.append(",isInverted=").append(getInverted());
1109 sb.append(",majorTickSpacing=").append(getMajorTickSpacing());
1110 sb.append(",minorTickSpacing=").append(getMinorTickSpacing());
1111 sb.append(",orientation=");
1112 if (orientation == HORIZONTAL)
1113 sb.append("HORIZONTAL");
1114 else
1115 sb.append("VERTICAL");
1116 sb.append(",paintLabels=").append(getPaintLabels());
1117 sb.append(",paintTicks=").append(getPaintTicks());
1118 sb.append(",paintTrack=").append(getPaintTrack());
1119 sb.append(",snapToTicks=").append(getSnapToTicks());
1120
1121 // the following is output by the reference implementation. We don't
1122 // strictly need to replicate this. Perhaps it has some meaning, but
1123 // I couldn't determine it yet...
1124 sb.append(",snapToValue=true");
1125
1126 return superParamStr + sb.toString();
1127 }
1128
1129 /**
1130 * Returns the object that provides accessibility features for this
1131 * <code>JSlider</code> component.
1132 *
1133 * @return The accessible context (an instance of {@link AccessibleJSlider}).
1134 */
1135 public AccessibleContext getAccessibleContext()
1136 {
1137 if (accessibleContext == null)
1138 accessibleContext = new AccessibleJSlider();
1139
1140 return accessibleContext;
1141 }
1142 }