/*
* PrefCheckBox.java
* de.sciss.gui package
*
* Copyright (c) 2004-2008 Hanns Holger Rutz. All rights reserved.
*
* This software is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either
* version 2, june 1991 of the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License (gpl.txt) along with this software; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*
* For further information, please contact Hanns Holger Rutz at
* contact@sciss.de
*
*
* Changelog:
* 20-May-05 created from de.sciss.meloncillo.gui.PrefCheckBox
*/
package de.sciss.gui;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.prefs.PreferenceChangeEvent;
import java.util.prefs.PreferenceChangeListener;
import java.util.prefs.Preferences;
import javax.swing.Action;
import javax.swing.JCheckBox;
import de.sciss.app.DynamicAncestorAdapter;
import de.sciss.app.DynamicListening;
import de.sciss.app.EventManager;
import de.sciss.app.LaterInvocationManager;
import de.sciss.app.PreferenceEntrySync;
/**
* Equips a normal JCheckBox with
* preference storing / recalling capabilities.
* To preserve maximum future compatibility,
* we decided to not override setSelected()
* and the like but to install an internal
* ActionListener. Thus, there are two ways
* to alter the gadget state, either by invoking
* the doClick() methods (DON'T USE setSelected()
* because it doesn't fire events) or by
* changing the associated preferences.
* The whole mechanism would be much simpler
* if we reduced listening to the preference
* changes, but a) this wouldn't track user
* GUI activities, b) the PrefCheckBox can
* be used with preferences set to null.
* When a preference change occurs, the
* doClick() method is called, allowing
* clients to add ActionListeners to the
* gadget in case they don't want to deal
* with preferences. However, when possible
* it is recommended to use PreferenceChangeListener
* mechanisms.
*
* @author Hanns Holger Rutz
* @version 0.28, 17-Apr-07
*
* @see java.util.prefs.PreferenceChangeListener
*/
public class PrefCheckBox
extends JCheckBox
implements DynamicListening, PreferenceChangeListener,
LaterInvocationManager.Listener, PreferenceEntrySync
{
private boolean listening = false;
private Preferences prefs = null;
private String key = null;
private final LaterInvocationManager lim = new LaterInvocationManager( this );
private ActionListener listener;
private boolean defaultValue;
private boolean readPrefs = true;
protected boolean writePrefs = true;
/**
* Constructs a new <code>PrefCheckBox</code>
* with no initial preferences set.
*/
public PrefCheckBox()
{
super();
init();
}
/**
* Constructs a new <code>PrefCheckBox</code>
* with a given text label and no preferences set.
*
* @param text label of the checkbox
*/
public PrefCheckBox( String text )
{
super( text );
init();
}
/**
* Constructs a new <code>PrefCheckBox</code>
* with a given action and no initial preferences set.
*
* @param a action to attach to the checkbox
*/
public PrefCheckBox( Action a )
{
super( a );
init();
}
private void init()
{
new DynamicAncestorAdapter( this ).addTo( this );
listener = new ActionListener() {
public void actionPerformed( ActionEvent e )
{
if( EventManager.DEBUG_EVENTS ) System.err.println( "@chbx actionPerformed : "+key+" --> "+isSelected() );
// guiState = isSelected();
if( writePrefs ) writePrefs();
}
};
}
public void setReadPrefs( boolean b )
{
if( b != readPrefs ) {
readPrefs = b;
if( (prefs != null) && listening ) {
if( readPrefs ) {
prefs.addPreferenceChangeListener( this );
} else {
prefs.removePreferenceChangeListener( this );
}
}
}
}
public boolean getReadPrefs()
{
return readPrefs;
}
public void setWritePrefs( boolean b )
{
if( b != writePrefs ) {
writePrefs = b;
if( (prefs != null) && listening ) {
if( writePrefs ) {
this.addActionListener( listener );
} else {
this.removeActionListener( listener );
}
}
}
}
public boolean getWritePrefs()
{
return writePrefs;
}
// public void setSelected( boolean state )
// {
// if( EventManager.DEBUG_EVENTS ) System.err.println( "@chbx setSelected : "+key+" --> "+state );
// super.setSelected( state );
// updatePrefs( state );
// }
public void writePrefs()
{
if( (prefs != null) && (key != null) ) {
final boolean guiState = isSelected();
final boolean prefsState = prefs.getBoolean( key, !guiState );
if( EventManager.DEBUG_EVENTS ) System.err.println( "@chbx updatePrefs : "+this.key+"; old = "+prefsState+" --> "+guiState );
if( prefsState != guiState ) {
prefs.putBoolean( key, guiState );
}
}
}
public void setPreferenceNode( Preferences prefs )
{
setPreferences( prefs, this.key );
}
public void setPreferenceKey( String key )
{
setPreferences( this.prefs, key );
}
public void setPreferences( Preferences prefs, String key )
{
if( (this.prefs == null) || (this.key == null) ) {
defaultValue = isSelected();
}
if( listening ) {
stopListening();
this.prefs = prefs;
this.key = key;
startListening();
} else {
this.prefs = prefs;
this.key = key;
}
}
public Preferences getPreferenceNode() { return prefs; }
public String getPreferenceKey() { return key; }
public void startListening()
{
if( prefs != null ) {
listening = true;
if( writePrefs ) this.addActionListener( listener );
if( readPrefs ) {
prefs.addPreferenceChangeListener( this );
readPrefs();
}
}
}
public void stopListening()
{
if( prefs != null ) {
if( readPrefs ) prefs.removePreferenceChangeListener( this );
if( writePrefs ) this.removeActionListener( listener );
listening = false;
}
}
// o instanceof PreferenceChangeEvent
public void laterInvocation( Object o )
{
String prefsValue = ((PreferenceChangeEvent) o).getNewValue();
readPrefsFromString( prefsValue );
}
public void readPrefs()
{
if( (prefs != null) && (key != null) ) readPrefsFromString( prefs.get( key, null ));
}
private void readPrefsFromString( String prefsValue )
{
if( prefsValue == null ) {
// if( listening && writePrefs ) this.removeActionListener( listener );
setSelected( defaultValue );
// if( listening && writePrefs ) this.addActionListener( listener );
if( writePrefs ) writePrefs();
return;
}
boolean prefsState;
boolean guiState = isSelected();
prefsState = new Boolean( prefsValue ).booleanValue();
if( prefsState != guiState ) {
// though we filter out events when preferences effectively
// remain unchanged, it's more clean and produces less
// overhead to temporarily remove our ActionListener
// so we don't produce potential loops
if( listening && writePrefs ) this.removeActionListener( listener );
if( EventManager.DEBUG_EVENTS ) System.err.println( "@chbx doClick" );
doClick(); // setSelected( b );
if( listening && writePrefs ) this.addActionListener( listener );
}
}
public void preferenceChange( PreferenceChangeEvent e )
{
if( e.getKey().equals( key )) {
if( EventManager.DEBUG_EVENTS ) System.err.println( "@chbx preferenceChange : "+key+" --> "+e.getNewValue() );
lim.queue( e );
}
}
}