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 package javax.swing;
  26 
  27 import java.awt.*;
  28 import java.awt.event.*;
  29 
  30 import javax.swing.event.*;
  31 import javax.swing.plaf.*;
  32 import javax.accessibility.*;
  33 
  34 import java.io.ObjectOutputStream;
  35 import java.io.ObjectInputStream;
  36 import java.io.IOException;
  37 
  38 
  39 /**
  40  * An implementation of a two-state button.
  41  * The <code>JRadioButton</code> and <code>JCheckBox</code> classes
  42  * are subclasses of this class.
  43  * For information on using them see
  44  * <a
  45  href="http://docs.oracle.com/javase/tutorial/uiswing/components/button.html">How to Use Buttons, Check Boxes, and Radio Buttons</a>,
  46  * a section in <em>The Java Tutorial</em>.
  47  * <p>
  48  * Buttons can be configured, and to some degree controlled, by
  49  * <code><a href="Action.html">Action</a></code>s.  Using an
  50  * <code>Action</code> with a button has many benefits beyond directly
  51  * configuring a button.  Refer to <a href="Action.html#buttonActions">
  52  * Swing Components Supporting <code>Action</code></a> for more
  53  * details, and you can find more information in <a
  54  * href="http://docs.oracle.com/javase/tutorial/uiswing/misc/action.html">How
  55  * to Use Actions</a>, a section in <em>The Java Tutorial</em>.
  56  * <p>
  57  * <strong>Warning:</strong> Swing is not thread safe. For more
  58  * information see <a
  59  * href="package-summary.html#threading">Swing's Threading
  60  * Policy</a>.
  61  * <p>
  62  * <strong>Warning:</strong>
  63  * Serialized objects of this class will not be compatible with
  64  * future Swing releases. The current serialization support is
  65  * appropriate for short term storage or RMI between applications running
  66  * the same version of Swing.  As of 1.4, support for long term storage
  67  * of all JavaBeans&trade;
  68  * has been added to the <code>java.beans</code> package.
  69  * Please see {@link java.beans.XMLEncoder}.
  70  *
  71  * @beaninfo
  72  *   attribute: isContainer false
  73  * description: An implementation of a two-state button.
  74  *
  75  * @see JRadioButton
  76  * @see JCheckBox
  77  * @author Jeff Dinkins
  78  * @since 1.2
  79  */
  80 @SuppressWarnings("serial") // Same-version serialization only
  81 public class JToggleButton extends AbstractButton implements Accessible {
  82 
  83     /**
  84      * @see #getUIClassID
  85      * @see #readObject
  86      */
  87     private static final String uiClassID = "ToggleButtonUI";
  88 
  89     /**
  90      * Creates an initially unselected toggle button
  91      * without setting the text or image.
  92      */
  93     public JToggleButton () {
  94         this(null, null, false);
  95     }
  96 
  97     /**
  98      * Creates an initially unselected toggle button
  99      * with the specified image but no text.
 100      *
 101      * @param icon  the image that the button should display
 102      */
 103     public JToggleButton(Icon icon) {
 104         this(null, icon, false);
 105     }
 106 
 107     /**
 108      * Creates a toggle button with the specified image
 109      * and selection state, but no text.
 110      *
 111      * @param icon  the image that the button should display
 112      * @param selected  if true, the button is initially selected;
 113      *                  otherwise, the button is initially unselected
 114      */
 115     public JToggleButton(Icon icon, boolean selected) {
 116         this(null, icon, selected);
 117     }
 118 
 119     /**
 120      * Creates an unselected toggle button with the specified text.
 121      *
 122      * @param text  the string displayed on the toggle button
 123      */
 124     public JToggleButton (String text) {
 125         this(text, null, false);
 126     }
 127 
 128     /**
 129      * Creates a toggle button with the specified text
 130      * and selection state.
 131      *
 132      * @param text  the string displayed on the toggle button
 133      * @param selected  if true, the button is initially selected;
 134      *                  otherwise, the button is initially unselected
 135      */
 136     public JToggleButton (String text, boolean selected) {
 137         this(text, null, selected);
 138     }
 139 
 140     /**
 141      * Creates a toggle button where properties are taken from the
 142      * Action supplied.
 143      *
 144      * @param a an instance of an {@code Action}
 145      * @since 1.3
 146      */
 147     public JToggleButton(Action a) {
 148         this();
 149         setAction(a);
 150     }
 151 
 152     /**
 153      * Creates a toggle button that has the specified text and image,
 154      * and that is initially unselected.
 155      *
 156      * @param text the string displayed on the button
 157      * @param icon  the image that the button should display
 158      */
 159     public JToggleButton(String text, Icon icon) {
 160         this(text, icon, false);
 161     }
 162 
 163     /**
 164      * Creates a toggle button with the specified text, image, and
 165      * selection state.
 166      *
 167      * @param text the text of the toggle button
 168      * @param icon  the image that the button should display
 169      * @param selected  if true, the button is initially selected;
 170      *                  otherwise, the button is initially unselected
 171      */
 172     public JToggleButton (String text, Icon icon, boolean selected) {
 173         // Create the model
 174         setModel(new ToggleButtonModel());
 175 
 176         model.setSelected(selected);
 177 
 178         // initialize
 179         init(text, icon);
 180     }
 181 
 182     /**
 183      * Resets the UI property to a value from the current look and feel.
 184      *
 185      * @see JComponent#updateUI
 186      */
 187     public void updateUI() {
 188         setUI((ButtonUI)UIManager.getUI(this));
 189     }
 190 
 191     /**
 192      * Returns a string that specifies the name of the l&amp;f class
 193      * that renders this component.
 194      *
 195      * @return String "ToggleButtonUI"
 196      * @see JComponent#getUIClassID
 197      * @see UIDefaults#getUI
 198      * @beaninfo
 199      *  description: A string that specifies the name of the L&amp;F class
 200      */
 201     public String getUIClassID() {
 202         return uiClassID;
 203     }
 204 
 205 
 206     /**
 207      * Overriden to return true, JToggleButton supports
 208      * the selected state.
 209      */
 210     boolean shouldUpdateSelectedStateFromAction() {
 211         return true;
 212     }
 213 
 214     // *********************************************************************
 215 
 216     /**
 217      * The ToggleButton model
 218      * <p>
 219      * <strong>Warning:</strong>
 220      * Serialized objects of this class will not be compatible with
 221      * future Swing releases. The current serialization support is
 222      * appropriate for short term storage or RMI between applications running
 223      * the same version of Swing.  As of 1.4, support for long term storage
 224      * of all JavaBeans&trade;
 225      * has been added to the <code>java.beans</code> package.
 226      * Please see {@link java.beans.XMLEncoder}.
 227      */
 228     @SuppressWarnings("serial") // Same-version serialization only
 229     public static class ToggleButtonModel extends DefaultButtonModel {
 230 
 231         /**
 232          * Creates a new ToggleButton Model
 233          */
 234         public ToggleButtonModel () {
 235         }
 236 
 237         /**
 238          * Checks if the button is selected.
 239          */
 240         public boolean isSelected() {
 241 //              if(getGroup() != null) {
 242 //                  return getGroup().isSelected(this);
 243 //              } else {
 244                 return (stateMask & SELECTED) != 0;
 245 //              }
 246         }
 247 
 248 
 249         /**
 250          * Sets the selected state of the button.
 251          * @param b true selects the toggle button,
 252          *          false deselects the toggle button.
 253          */
 254         public void setSelected(boolean b) {
 255             ButtonGroup group = getGroup();
 256             if (group != null) {
 257                 // use the group model instead
 258                 group.setSelected(this, b);
 259                 b = group.isSelected(this);
 260             }
 261 
 262             if (isSelected() == b) {
 263                 return;
 264             }
 265 
 266             if (b) {
 267                 stateMask |= SELECTED;
 268             } else {
 269                 stateMask &= ~SELECTED;
 270             }
 271 
 272             // Send ChangeEvent
 273             fireStateChanged();
 274 
 275             // Send ItemEvent
 276             fireItemStateChanged(
 277                     new ItemEvent(this,
 278                                   ItemEvent.ITEM_STATE_CHANGED,
 279                                   this,
 280                                   this.isSelected() ?  ItemEvent.SELECTED : ItemEvent.DESELECTED));
 281 
 282         }
 283 
 284         /**
 285          * Sets the pressed state of the toggle button.
 286          */
 287         public void setPressed(boolean b) {
 288             if ((isPressed() == b) || !isEnabled()) {
 289                 return;
 290             }
 291 
 292             if (b == false && isArmed()) {
 293                 setSelected(!this.isSelected());
 294             }
 295 
 296             if (b) {
 297                 stateMask |= PRESSED;
 298             } else {
 299                 stateMask &= ~PRESSED;
 300             }
 301 
 302             fireStateChanged();
 303 
 304             if(!isPressed() && isArmed()) {
 305                 int modifiers = 0;
 306                 AWTEvent currentEvent = EventQueue.getCurrentEvent();
 307                 if (currentEvent instanceof InputEvent) {
 308                     modifiers = ((InputEvent)currentEvent).getModifiers();
 309                 } else if (currentEvent instanceof ActionEvent) {
 310                     modifiers = ((ActionEvent)currentEvent).getModifiers();
 311                 }
 312                 fireActionPerformed(
 313                     new ActionEvent(this, ActionEvent.ACTION_PERFORMED,
 314                                     getActionCommand(),
 315                                     EventQueue.getMostRecentEventTime(),
 316                                     modifiers));
 317             }
 318 
 319         }
 320     }
 321 
 322 
 323     /**
 324      * See readObject() and writeObject() in JComponent for more
 325      * information about serialization in Swing.
 326      */
 327     private void writeObject(ObjectOutputStream s) throws IOException {
 328         s.defaultWriteObject();
 329         if (getUIClassID().equals(uiClassID)) {
 330             byte count = JComponent.getWriteObjCounter(this);
 331             JComponent.setWriteObjCounter(this, --count);
 332             if (count == 0 && ui != null) {
 333                 ui.installUI(this);
 334             }
 335         }
 336     }
 337 
 338 
 339     /**
 340      * Returns a string representation of this JToggleButton. This method
 341      * is intended to be used only for debugging purposes, and the
 342      * content and format of the returned string may vary between
 343      * implementations. The returned string may be empty but may not
 344      * be <code>null</code>.
 345      *
 346      * @return  a string representation of this JToggleButton.
 347      */
 348     protected String paramString() {
 349         return super.paramString();
 350     }
 351 
 352 
 353 /////////////////
 354 // Accessibility support
 355 ////////////////
 356 
 357     /**
 358      * Gets the AccessibleContext associated with this JToggleButton.
 359      * For toggle buttons, the AccessibleContext takes the form of an
 360      * AccessibleJToggleButton.
 361      * A new AccessibleJToggleButton instance is created if necessary.
 362      *
 363      * @return an AccessibleJToggleButton that serves as the
 364      *         AccessibleContext of this JToggleButton
 365      * @beaninfo
 366      *       expert: true
 367      *  description: The AccessibleContext associated with this ToggleButton.
 368      */
 369     public AccessibleContext getAccessibleContext() {
 370         if (accessibleContext == null) {
 371             accessibleContext = new AccessibleJToggleButton();
 372         }
 373         return accessibleContext;
 374     }
 375 
 376     /**
 377      * This class implements accessibility support for the
 378      * <code>JToggleButton</code> class.  It provides an implementation of the
 379      * Java Accessibility API appropriate to toggle button user-interface
 380      * elements.
 381      * <p>
 382      * <strong>Warning:</strong>
 383      * Serialized objects of this class will not be compatible with
 384      * future Swing releases. The current serialization support is
 385      * appropriate for short term storage or RMI between applications running
 386      * the same version of Swing.  As of 1.4, support for long term storage
 387      * of all JavaBeans&trade;
 388      * has been added to the <code>java.beans</code> package.
 389      * Please see {@link java.beans.XMLEncoder}.
 390      */
 391     @SuppressWarnings("serial") // Same-version serialization only
 392     protected class AccessibleJToggleButton extends AccessibleAbstractButton
 393             implements ItemListener {
 394 
 395         /**
 396          * Constructs {@code AccessibleJToggleButton}
 397          */
 398         public AccessibleJToggleButton() {
 399             super();
 400             JToggleButton.this.addItemListener(this);
 401         }
 402 
 403         /**
 404          * Fire accessible property change events when the state of the
 405          * toggle button changes.
 406          */
 407         public void itemStateChanged(ItemEvent e) {
 408             JToggleButton tb = (JToggleButton) e.getSource();
 409             if (JToggleButton.this.accessibleContext != null) {
 410                 if (tb.isSelected()) {
 411                     JToggleButton.this.accessibleContext.firePropertyChange(
 412                             AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
 413                             null, AccessibleState.CHECKED);
 414                 } else {
 415                     JToggleButton.this.accessibleContext.firePropertyChange(
 416                             AccessibleContext.ACCESSIBLE_STATE_PROPERTY,
 417                             AccessibleState.CHECKED, null);
 418                 }
 419             }
 420         }
 421 
 422         /**
 423          * Get the role of this object.
 424          *
 425          * @return an instance of AccessibleRole describing the role of the
 426          * object
 427          */
 428         public AccessibleRole getAccessibleRole() {
 429             return AccessibleRole.TOGGLE_BUTTON;
 430         }
 431     } // inner class AccessibleJToggleButton
 432 }