Source for gnu.java.awt.peer.swing.SwingCheckboxPeer

   1: /* SwingCheckboxPeer.java -- A Swing based peer for AWT checkboxes
   2:    Copyright (C)  2007  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: package gnu.java.awt.peer.swing;
  39: 
  40: import java.awt.Button;
  41: import java.awt.Checkbox;
  42: import java.awt.CheckboxGroup;
  43: import java.awt.Container;
  44: import java.awt.Graphics;
  45: import java.awt.Image;
  46: import java.awt.Label;
  47: import java.awt.Point;
  48: import java.awt.event.ActionEvent;
  49: import java.awt.event.ActionListener;
  50: import java.awt.event.FocusEvent;
  51: import java.awt.event.ItemEvent;
  52: import java.awt.event.ItemListener;
  53: import java.awt.event.KeyEvent;
  54: import java.awt.event.MouseEvent;
  55: import java.awt.peer.CheckboxPeer;
  56: 
  57: import javax.swing.JCheckBox;
  58: import javax.swing.JComponent;
  59: import javax.swing.JLabel;
  60: import javax.swing.JToggleButton;
  61: 
  62: /**
  63:  * A CheckboxPeer implementation that is backed by the Swing JCheckBox.
  64:  */
  65: public class SwingCheckboxPeer extends SwingComponentPeer implements
  66:         CheckboxPeer {
  67: 
  68:   /**
  69:    * A spezialized Swing checkbox used to paint the checkbox for the
  70:    * AWT checkbox. 
  71:    */
  72:   private class SwingCheckbox
  73:     extends JCheckBox
  74:     implements SwingComponent
  75:   {
  76:     Checkbox checkbox;
  77: 
  78:     SwingCheckbox(Checkbox checkbox)
  79:     {
  80:       this.checkbox = checkbox;
  81:     }
  82: 
  83:     /**
  84:      * Returns this checkbox.
  85:      *
  86:      * @return <code>this</code>
  87:      */
  88:     public JComponent getJComponent()
  89:     {
  90:       return this;
  91:     }
  92: 
  93:     /**
  94:      * Handles mouse events by forwarding it to
  95:      * <code>processMouseEvent()</code>.
  96:      *
  97:      * @param ev the mouse event
  98:      */
  99:     public void handleMouseEvent(MouseEvent ev)
 100:     {
 101:       ev.setSource(this);
 102:       processMouseEvent(ev);
 103:     }
 104: 
 105:     /**
 106:      * Handles mouse motion events by forwarding it to
 107:      * <code>processMouseMotionEvent()</code>.
 108:      *
 109:      * @param ev the mouse motion event
 110:      */
 111:     public void handleMouseMotionEvent(MouseEvent ev)
 112:     {
 113:       ev.setSource(this);
 114:       processMouseMotionEvent(ev);
 115:     }
 116: 
 117:     /**
 118:      * Handles key events by forwarding it to <code>processKeyEvent()</code>.
 119:      *
 120:      * @param ev the mouse event
 121:      */
 122:     public void handleKeyEvent(KeyEvent ev)
 123:     {
 124:       ev.setSource(this);
 125:       processKeyEvent(ev);
 126:     }
 127: 
 128:     /**
 129:      * Handles focus events by forwarding it to
 130:      * <code>processFocusEvent()</code>.
 131:      *
 132:      * @param ev the Focus event
 133:      */
 134:     public void handleFocusEvent(FocusEvent ev)
 135:     {
 136:       processFocusEvent(ev);
 137:     }
 138: 
 139:     /**
 140:      * Overridden so that this method returns the correct value even without a
 141:      * peer.
 142:      *
 143:      * @return the screen location of the button
 144:      */
 145:     public Point getLocationOnScreen()
 146:     {
 147:       return SwingCheckboxPeer.this.getLocationOnScreen();
 148:     }
 149: 
 150:     /**
 151:      * Overridden so that the isShowing method returns the correct value
 152:      * for the swing button, even if it has no peer on its own.
 153:      *
 154:      * @return <code>true</code> if the button is currently showing,
 155:      *         <code>false</code> otherwise
 156:      */
 157:     public boolean isShowing()
 158:     {
 159:       boolean retVal = false;
 160:       if (checkbox != null)
 161:         retVal = checkbox.isShowing();
 162:       return retVal;
 163:     }
 164: 
 165:     /**
 166:      * Overridden, so that the Swing button can create an Image without its
 167:      * own peer.
 168:      *
 169:      * @param w the width of the image
 170:      * @param h the height of the image
 171:      *
 172:      * @return an image
 173:      */
 174:     public Image createImage(int w, int h)
 175:     {
 176:       return SwingCheckboxPeer.this.createImage(w, h);
 177:     }
 178: 
 179:     public Graphics getGraphics()
 180:     {
 181:       return SwingCheckboxPeer.this.getGraphics();
 182:     }
 183: 
 184:     public Container getParent()
 185:     {
 186:       Container par = null;
 187:       if (checkbox != null)
 188:         par = checkbox.getParent();
 189:       return par;
 190:     }
 191: 
 192:     public void requestFocus() {
 193:       SwingCheckboxPeer.this.requestFocus(awtComponent, false, true, 0);
 194:     }
 195: 
 196:     public boolean requestFocus(boolean temporary) {
 197:       return SwingCheckboxPeer.this.requestFocus(awtComponent, temporary,
 198:                                                  true, 0);
 199:     }
 200:   }
 201: 
 202:   /**
 203:    * Listens for ActionEvents on the Swing button and triggers corresponding
 204:    * ActionEvents on the AWT button.
 205:    */
 206:   class SwingCheckboxListener implements ItemListener
 207:   {
 208:     Checkbox awtCheckbox;
 209: 
 210:     SwingCheckboxListener(Checkbox checkbox)
 211:     {
 212:       awtCheckbox = checkbox;
 213:     }
 214: 
 215:     /**
 216:      * Receives notification when an action was performend on the button.
 217:      *
 218:      * @param event the action event
 219:      */ 
 220:     public void itemStateChanged(ItemEvent event)
 221:     {
 222:       awtCheckbox.setState(event.getStateChange()==ItemEvent.SELECTED);
 223:       ItemListener[] l = awtCheckbox.getItemListeners();
 224:       if (l.length == 0)
 225:         return;
 226:       ItemEvent ev = new ItemEvent(awtCheckbox, ItemEvent.ITEM_STATE_CHANGED,
 227:                                    awtCheckbox, event.getStateChange());
 228:       for (int i = 0; i < l.length; ++i)
 229:         l[i].itemStateChanged(ev);
 230:     }
 231:   }
 232:     
 233:   /**
 234:    * Creates a new SwingCheckboxPeer instance.
 235:    */
 236:   public SwingCheckboxPeer(Checkbox checkbox)
 237:   {
 238:     SwingCheckbox swingCheckbox = new SwingCheckbox(checkbox);
 239:     swingCheckbox.addItemListener(new SwingCheckboxListener(checkbox));
 240: 
 241:     init(checkbox, swingCheckbox);
 242:     setLabel(checkbox.getLabel());
 243:     setState(checkbox.getState());
 244:   }
 245: 
 246:   public void setCheckboxGroup(CheckboxGroup group)
 247:   {
 248:     // TODO: Implement this.
 249:   }
 250: 
 251:   public void setLabel(String label)
 252:   {
 253:     ((JToggleButton) swingComponent).setText(label);
 254:   }
 255: 
 256:   public void setState(boolean state)
 257:   {
 258:     ((JToggleButton) swingComponent).setSelected(state);
 259:   }
 260: 
 261: }