ObserveDialog.java

/**
 * ObserveDialog.java
 * @author Fabio G. Cozman 
 *  Original version by  Sreekanth Nagarajan, rewritten from scratch
 *  by Fabio Cozman.
 * Copyright 1996 - 1999, Fabio G. Cozman,
 *          Carnergie Mellon University, Universidade de Sao Paulo
 * fgcozman@usp.br, http://www.cs.cmu.edu/~fgcozman/home.html
 *
 * The JavaBayes distribution 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), 
 * provided that this notice and the name of the author appear in all 
 * copies. Upon request to the author, some of the packages in the 
 * JavaBayes distribution can be licensed under the GNU Lesser General
 * Public License as published by the Free Software Foundation (either
 * version 2 of the License, or (at your option) any later version).
 * If you're using the software, please notify fgcozman@usp.br so
 * that you can receive updates and patches. JavaBayes is distributed
 * "as is", 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
 * along with the JavaBayes distribution. If not, write to the Free
 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

package JavaBayesInterface;

import InferenceGraphs.*;

import java.awt.*;

class ObserveDialog extends Dialog {
    NetworkPanel npan;
    
    InferenceGraph ig;
    InferenceGraphNode node;

    boolean observed;

    Checkbox observedBox;
    List valuesList;

    /* ************************************************* *
     * Default constructor for an ObserveDialog object.  *
     * ************************************************* */
    public ObserveDialog(NetworkPanel network_panel, Frame parent,
    InferenceGraph i_g, InferenceGraphNode node) {
    	super(parent, "Set Observe Value", true);
    	this.ig = i_g;
    	this.node = node;
    	this.npan = network_panel;

    	Panel cbp = new Panel();
    	cbp.setLayout(new FlowLayout(FlowLayout.CENTER));

    	observed = node.is_observed();
    	observedBox = new Checkbox("Observed", null, observed);
    	cbp.add(observedBox);

    	Panel listp = new Panel();
	    listp.setLayout(new GridLayout(1, 1));
    	valuesList = new List(6, false);

    	String[] values = node.get_values();
    	for (int i=0; i < values.length; i++)
	        valuesList.addItem(new String(values[i]));

    	if (observed) {
    	    valuesList.select(node.get_observed_value());
        }

    	listp.add(valuesList);

    	Panel okp = new Panel();
	    okp.setLayout(new FlowLayout(FlowLayout.CENTER));
    	okp.add(new Button("Ok"));
    	okp.add(new Button("Cancel"));

        setLayout(new BorderLayout());
    	add("North", cbp);
    	add("Center", listp);
	    add("South", okp);
    	pack();
    }

    /* ************************************************** *
     * Handle the observation events.                     *
     * ************************************************** */
    public boolean action(Event evt, Object arg) {
    	if (evt.target == observedBox) {
    	  observed = observedBox.getState();
    	  if (observed)
            valuesList.select(0);	// select first value by default
        else	// clear any selection
	         valuesList.deselect(valuesList.getSelectedIndex());
    	  return super.action(evt, arg);
    	} else if (evt.target == valuesList) {
    	  if (! observed) {
    	      observed = true;
            observedBox.setState(observed);
        }
        return super.action(evt, arg);
	   } else if (arg.equals("Ok")) {
    	  String selValue = null;
	     observed = observedBox.getState();
	     selValue = valuesList.getSelectedItem();
    	  if (observed && selValue == null) {
	         JavaBayesHelpMessages.show(JavaBayesHelpMessages.observe_error);
            return true; // do not close this dialog box
        }
        if (observed)
    	      node.set_observation_value(selValue);
        else
	         node.clear_observation();
	     npan.repaint();
        dispose();
      } else if (arg.equals("Cancel")) {
	     dispose();
      } else return super.action(evt, arg);
    	return true;
    }

}