Source for javax.swing.JCheckBoxMenuItem

   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., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 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 javax.accessibility.Accessible;
  42: import javax.accessibility.AccessibleContext;
  43: import javax.accessibility.AccessibleRole;
  44: 
  45: /**
  46:  * A menu item that displays a checkbox. Its behaviour is very similar
  47:  * to {@link JCheckBox}. Just like the <code>JCheckBox</code>, user can check
  48:  * and uncheck this menu item by clicking on it. Also
  49:  * {@link AbstractButton#setSelected} and {@link #setState} can be use used
  50:  * for the same purpose.
  51:  * <code>JCheckBoxMenuItem</code> uses
  52:  * <code>ToggleButtonModel</code> to keep track of its selection.
  53:  *
  54:  * @author original author unknown
  55:  */
  56: public class JCheckBoxMenuItem extends JMenuItem implements SwingConstants,
  57:                                                             Accessible
  58: {
  59:   private static final long serialVersionUID = -6676402307973384715L;
  60: 
  61:   /** name for the UI delegate for this menuItem. */
  62:   private static final String uiClassID = "CheckBoxMenuItemUI";
  63: 
  64:   /** Indicates whether this menu item is checked. */
  65:   private boolean state;
  66: 
  67:   /**
  68:    * This array contains text of this menu item if this menu item is in
  69:    * checked state and null it is not.
  70:    */
  71:   private Object[] selectedObjects = new Object[1];
  72: 
  73:   /**
  74:    * Creates a new JCheckBoxMenuItem object.
  75:    */
  76:   public JCheckBoxMenuItem()
  77:   {
  78:     this(null, null);
  79:   }
  80: 
  81:   /**
  82:    * Creates a new JCheckBoxMenuItem with given icon
  83:    *
  84:    * @param icon Icon for this menu item
  85:    */
  86:   public JCheckBoxMenuItem(Icon icon)
  87:   {
  88:     this(null, icon);
  89:   }
  90: 
  91:   /**
  92:    * Creates a new JCheckBoxMenuItem with given label
  93:    *
  94:    * @param text Label for this menu item
  95:    */
  96:   public JCheckBoxMenuItem(String text)
  97:   {
  98:     this(text, null);
  99:   }
 100: 
 101:   /**
 102:    * Creates a new JCheckBoxMenuItem using given action
 103:    *
 104:    * @param action Action for this menu item.
 105:    */
 106:   public JCheckBoxMenuItem(Action action)
 107:   {
 108:     this();
 109:     setAction(action);
 110:   }
 111: 
 112:   /**
 113:    * Creates a new JCheckBoxMenuItem object with given label and icon
 114:    *
 115:    * @param text Label for this menu item
 116:    * @param icon Icon for this menu item
 117:    */
 118:   public JCheckBoxMenuItem(String text, Icon icon)
 119:   {
 120:     this(text, icon, false);
 121:   }
 122: 
 123:   /**
 124:    * Creates a new JCheckBoxMenuItem object using specified label and
 125:    * marked as checked if given 'state' is true.
 126:    *
 127:    * @param text Label for this menu item
 128:    * @param state <code>true</code> if this item should be in checked state and
 129:    *     <code>false</code> otherwise
 130:    */
 131:   public JCheckBoxMenuItem(String text, boolean state)
 132:   {
 133:     this(text, null, state);
 134:   }
 135: 
 136:   /**
 137:    * Creates a new JCheckBoxMenuItem object with given label, icon,
 138:    * and marked as checked if given 'state' is true.
 139:    *
 140:    * @param text Label for this menu item
 141:    * @param icon icon for this menu item
 142:    * @param state <code>true</code> if this item should be in checked state and
 143:    *     false otherwise
 144:    */
 145:   public JCheckBoxMenuItem(String text, Icon icon, boolean state)
 146:   {
 147:     super(text, icon);
 148:     setModel(new JToggleButton.ToggleButtonModel());
 149:     this.state = state;
 150:     this.setVisible(true);
 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:   public synchronized void setState(boolean state)
 183:   {
 184:     this.state = state;
 185:   }
 186: 
 187:   /**
 188:    * This method returns array containing label of this
 189:    * menu item if it is selected and null otherwise.
 190:    *
 191:    * @return Array containing label of this
 192:    *     menu item if this menu item is selected or null otherwise.
 193:    */
 194:   public Object[] getSelectedObjects()
 195:   {
 196:     if (state == true)
 197:       selectedObjects[0] = this.getText();
 198:     else
 199:       selectedObjects[0] = null;
 200: 
 201:     return selectedObjects;
 202:   }
 203: 
 204:   /**
 205:     * This method overrides JComponent.requestFocus with an empty
 206:     * implementation, since JCheckBoxMenuItems should not
 207:     * receve focus in general.
 208:     */
 209:   public void requestFocus()
 210:   {
 211:     //  Should do nothing here
 212:   }
 213: 
 214:   /**
 215:    * A string that describes this JCheckBoxMenuItem. Normally only used
 216:    * for debugging.
 217:    *
 218:    * @return A string describing this JCheckBoxMenuItem
 219:    */
 220:   protected String paramString()
 221:   {
 222:     return "JCheckBoxMenuItem";
 223:   }
 224: 
 225:   public AccessibleContext getAccessibleContext()
 226:   {
 227:     if (accessibleContext == null)
 228:       accessibleContext = new AccessibleJCheckBoxMenuItem();
 229: 
 230:     return accessibleContext;
 231:   }
 232: 
 233:   /**
 234:    * Accessibility support for <code>JCheckBoxMenuItem</code>.
 235:    */
 236:   protected class AccessibleJCheckBoxMenuItem extends AccessibleJMenuItem
 237:   {
 238:     private static final long serialVersionUID = 1079958073579370777L;
 239: 
 240:     /**
 241:      * Creates a new AccessibleJCheckBoxMenuItem object.
 242:      */
 243:     protected AccessibleJCheckBoxMenuItem()
 244:     {
 245:       // Nothing to do here.
 246:     }
 247: 
 248:     public AccessibleRole getAccessibleRole()
 249:     {
 250:       return AccessibleRole.CHECK_BOX;
 251:     }
 252:   }
 253: }