libjava/javax/swing/JCheckBoxMenuItem.java

   1 /* JCheckBoxMenuItem.java --
   2    Copyright (C) 2002, 2004 Free Software Foundation, Inc.
   3
   4 This file is part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; see the file COPYING.  If not, write to the
  18 Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19 02111-1307 USA.
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version. */
  37
  38
  39 package javax.swing;
  40
  41 import java.io.IOException;
  42 import java.io.ObjectOutputStream;
  43
  44 import javax.accessibility.Accessible;
  45 import javax.accessibility.AccessibleContext;
  46 import javax.accessibility.AccessibleRole;
  47
  48 /**
  49  * This class represents JCheckBoxMenuItem. Its behaviour is very similar
  50  * to JCheckBoxButton. Just like the JCheckBoxButton, user can check and
  51  * uncheck this menu item by clicking on it. Also setSelected()/setState()
  52  * can be use used for the same purpose. JCheckBoxMenuItem uses
  53  * ToggleButtonModel to keep track of its selection.
  54  */
  55 public class JCheckBoxMenuItem extends JMenuItem implements SwingConstants,
  56                                                             Accessible
  57 {
  58   private static final long serialVersionUID = -6676402307973384715L;
  59
  60   /** name for the UI delegate for this menuItem. */
  61   private static final String uiClassID = "CheckBoxMenuItemUI";
  62
  63   /** Indicates whether this menu item is checked. */
  64   private boolean state;
  65
  66   /**
  67    * This array contains text of this menu item if this menu item is in
  68    * checked state and null it is not.
  69    */
  70   private Object[] selectedObjects = new Object[1];
  71
  72   /**
  73    * Creates a new JCheckBoxMenuItem object.
  74    */
  75   public JCheckBoxMenuItem()
  76   {
  77     this(null, null);
  78   }
  79
  80   /**
  81    * Creates a new JCheckBoxMenuItem with given icon
  82    *
  83    * @param icon Icon for this menu item
  84    */
  85   public JCheckBoxMenuItem(Icon icon)
  86   {
  87     this(null, icon);
  88   }
  89
  90   /**
  91    * Creates a new JCheckBoxMenuItem with given label
  92    *
  93    * @param text Label for this menu item
  94    */
  95   public JCheckBoxMenuItem(String text)
  96   {
  97     this(text, null);
  98   }
  99
 100   /**
 101    * Creates a new JCheckBoxMenuItem using given action
 102    *
 103    * @param action Action for this menu item.
 104    */
 105   public JCheckBoxMenuItem(Action action)
 106   {
 107     this();
 108     setAction(action);
 109   }
 110
 111   /**
 112    * Creates a new JCheckBoxMenuItem object with given label and icon
 113    *
 114    * @param text Label for this menu item
 115    * @param icon Icon for this menu item
 116    */
 117   public JCheckBoxMenuItem(String text, Icon icon)
 118   {
 119     this(text, icon, false);
 120   }
 121
 122   /**
 123    * Creates a new JCheckBoxMenuItem object using specified label and
 124    * marked as checked if given 'state' is true
 125    *
 126    * @param text Label for this menu item
 127    * @param state True if this item should be in checked state and false otherwise
 128    */
 129   public JCheckBoxMenuItem(String text, boolean state)
 130   {
 131     this(text, null, state);
 132   }
 133
 134   /**
 135    * Creates a new JCheckBoxMenuItem object with given label, icon,
 136    * and marked as checked if given 'state' is true
 137    *
 138    * @param text Label for this menu item
 139    * @param icon icon for this menu item
 140    * @param state  True if this item should be in checked state and false otherwise
 141    */
 142   public JCheckBoxMenuItem(String text, Icon icon, boolean state)
 143   {
 144     super(text, icon);
 145     setModel(new JToggleButton.ToggleButtonModel());
 146     this.state = state;
 147   }
 148
 149   private void writeObject(ObjectOutputStream stream) throws IOException
 150   {
 151   }
 152
 153   /**
 154    * This method returns a name to identify which look and feel class will be
 155    * the UI delegate for the menuItem.
 156    *
 157    * @return The Look and Feel classID. "JCheckBoxMenuItemUI"
 158    */
 159   public String getUIClassID()
 160   {
 161     return uiClassID;
 162   }
 163
 164   /**
 165    * Returns checked state for this check box menu item.
 166    *
 167    * @return Returns true if this menu item is in checked state
 168    * and false otherwise.
 169    */
 170   public boolean getState()
 171   {
 172     return state;
 173   }
 174
 175   /**
 176    * Sets state for this check box menu item. If
 177    * given 'state' is true, then mark menu item as checked,
 178    * and uncheck this menu item otherwise.
 179    *
 180    * @param state new state for this menu item
 181    *
 182    */
 183   public synchronized void setState(boolean state)
 184   {
 185     this.state = state;
 186   }
 187
 188   /**
 189    * This method returns array containing label of this
 190    * menu item if it is selected and null otherwise.
 191    *
 192    * @return Array containing label of this
 193    * menu item if this menu item is selected or null otherwise.
 194    */
 195   public Object[] getSelectedObjects()
 196   {
 197     if (state == true)
 198       selectedObjects[0] = this.getText();
 199     else
 200       selectedObjects[0] = null;
 201
 202     return selectedObjects;
 203   }
 204
 205   /**
 206     * This method overrides JComponent.requestFocus with an empty
 207     * implementation, since JCheckBoxMenuItems should not
 208     * receve focus in general.
 209     */
 210   public void requestFocus()
 211   {
 212     //  Should do nothing here
 213   }
 214
 215   /**
 216    * A string that describes this JCheckBoxMenuItem. Normally only used
 217    * for debugging.
 218    *
 219    * @return A string describing this JCheckBoxMenuItem
 220    */
 221   protected String paramString()
 222   {
 223     return "JCheckBoxMenuItem";
 224   }
 225
 226   public AccessibleContext getAccessibleContext()
 227   {
 228     if (accessibleContext == null)
 229       accessibleContext = new AccessibleJCheckBoxMenuItem();
 230
 231     return accessibleContext;
 232   }
 233
 234   protected class AccessibleJCheckBoxMenuItem extends AccessibleJMenuItem
 235   {
 236     private static final long serialVersionUID = 1079958073579370777L;
 237
 238     /**
 239      * Creates a new AccessibleJCheckBoxMenuItem object.
 240      */
 241     protected AccessibleJCheckBoxMenuItem()
 242     {
 243     }
 244
 245     public AccessibleRole getAccessibleRole()
 246     {
 247       return AccessibleRole.CHECK_BOX;
 248     }
 249   }
 250 }