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1   /*
2    *  XNap - A P2P framework and client.
3    *
4    *  See the file AUTHORS for copyright information.
5    *
6    *  This program 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.
9    *
10   *  This program is distributed in the hope that it will be useful,
11   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13   *  GNU General Public License for more details.
14   *
15   *  You should have received a copy of the GNU General Public License
16   *  along with this program; if not, write to the Free Software
17   *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18   */
19  
20  package org.xnap.action;
21  
22  import java.awt.event.ActionEvent;
23  
24  import javax.swing.AbstractAction;
25  import javax.swing.AbstractButton;
26  
27  /***
28   * Provides a default implementation for toggeable <code>Action</code> objects.
29   */
30  public abstract class AbstractToggleAction extends AbstractAction 
31      implements ToggleAction
32  {
33      
34      //--- Constant(s) ---
35      
36      //--- Data field(s) ---
37      
38      //--- Constructor(s) ---
39      
40      public AbstractToggleAction(boolean selected)
41      {
42  		putValue("selected", new Boolean(selected));
43      }
44  
45      /***
46       * Constructor an AbstractToggleAction that is not selected by default.
47       */
48      public AbstractToggleAction()
49      {
50  		this(false);
51      }
52  
53      //--- Method(s) ---
54          
55      public boolean isSelected()
56      {
57  		return ((Boolean)getValue("selected")).booleanValue();
58      }
59  
60      public void actionPerformed(ActionEvent event) 
61      {
62  		if (event.getSource() instanceof AbstractButton) {
63  			AbstractButton ab = (AbstractButton)event.getSource();
64  			setSelected(ab.isSelected());
65  		}
66      }
67  
68      /***
69       * Invoked when the selection changes.
70       */
71      public abstract void toggled(boolean selected);
72          
73      public void setSelected(boolean newValue)
74      {
75  		if (newValue != isSelected()) {
76  			putValue("selected", new Boolean(newValue));
77  			toggled(newValue);
78  		}
79      }
80      
81  }