NullableObject.java

/*
 * File    : NullableObject.java
 * Created : 04-nov-2002 15:30
 * By      : fbusquets
 *
 * JClic - Authoring and playing system for educational activities
 *
 * Copyright (C) 2000 - 2005 Francesc Busquets & Departament
 * d'Educacio de la Generalitat de Catalunya
 *
 * This program 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 of the License, or
 * (at your option) any later version.
 *
 * This program 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 (see the LICENSE file).
 */

package edu.xtec.jclic.beans;

import edu.xtec.util.Options;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.AbstractButton;
import javax.swing.Icon;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JPanel;

/**
 *
 * @author Francesc Busquets (fbusquets@xtec.cat)
 * @version 13.08.29
 */
public class NullableObject extends JPanel implements ActionListener {
    
    public static final String PROP_CUSTOM_OBJECT = "customObject";
        
    protected Object object;
    protected JCheckBox check;
    protected boolean nullValue;
    protected AbstractButton button;
    protected Options options;
    protected boolean modified;
        
    public static final int PANEL_HEIGHT=21, CHECK_WIDTH=14, BUTTON_WIDTH=31;
    public static final Dimension btDim=new Dimension(BUTTON_WIDTH, PANEL_HEIGHT);
    public static final Dimension checkDim=new Dimension(CHECK_WIDTH, PANEL_HEIGHT);
    public static final Dimension panelDim=new Dimension(BUTTON_WIDTH+CHECK_WIDTH, PANEL_HEIGHT);
    
    /** Creates new NullableObject */
    public NullableObject() {
        
        super(new java.awt.BorderLayout());
        setOpaque(false);
        nullValue=true;
        
        //setOpaque(false);
        
        check=new JCheckBox();
        check.setPreferredSize(checkDim);
        check.setMinimumSize(checkDim);
        check.setFocusPainted(false);
        //check.setOpaque(false);        
        check.setSelected(false);
        add(check, java.awt.BorderLayout.WEST);
        
        button=buildButton();
        button.setPreferredSize(btDim);
        button.setMinimumSize(btDim);
        button.setFocusPainted(false);
        add(button, java.awt.BorderLayout.CENTER);
        
        check.addActionListener(this);
        button.addActionListener(this);
    }
    
    protected String getObjectType(){
        return PROP_CUSTOM_OBJECT;
    }
    
    protected Object createObject(){
        return new Object();
    }
    
    protected AbstractButton buildButton(){
        return new JButton();
    }
    
    public boolean isModified(){
        return modified;
    }
    
    public void setModified(boolean modified){
        this.modified=modified;
    }
    
    protected Object editObject(Object o){
        return o;
    };
    
    @Override
    public void setToolTipText(String text){
        super.setToolTipText(text);
        if(button!=null)
            button.setToolTipText(text);
        if(check!=null)
            check.setToolTipText(text);
    }
    
    @Override
    public void setEnabled(boolean enabled){
        super.setEnabled(enabled);
        if(button!=null)
            button.setEnabled(enabled);
        if(check!=null)
            check.setEnabled(enabled);        
    }
    
    @Override
    public void setName(String name){
        if(check!=null)
            check.setText(name);
    }
    
    public void setText(String text){
        if(check!=null)
            check.setText(text);
    }
    
    public void setOptions(Options options){
        this.options=options;
    }
    
    public Options getOptions(){
        return options;
    }
    
    public Object getObject() {
        return nullValue ? null : object;
    }
    
    public void clear(){
        setObject((object=null));
    }
    
    public void setObject(Object value) {                
        nullValue=(value==null);
        if(!nullValue)
            object=value;        
        check.setSelected(!nullValue);
        button.repaint();        
    }
    
    public void changeObject(Object o){
        Object oldValue=getObject();        
        setObject(o);
        Object newValue=getObject();        
        if((oldValue==null && newValue!=null) || (oldValue!=null && !oldValue.equals(newValue)))
            firePropertyChange(getObjectType(), oldValue, getObject());
    }
    
    public void setIcon(Icon icon){
        button.setIcon(icon);
    }
    
    public Icon getIcon(){
        return button.getIcon();
    }
    
    public void actionPerformed(ActionEvent ev){
        if(ev!=null){
            if(button.equals(ev.getSource())){
                modified=true;
                Object o=editObject(object);
                if(o!=null)
                    changeObject(o);
            }
            else if(check.equals(ev.getSource())){
                changeObject(check.isSelected() ? (object==null ? createObject() : object) : null);
                modified=true;
            }
        }
    }    
}