testcheckboxgroups.java

java2 primer plus一书源程序

/*
 * TestCheckboxGroups.java
 *
 * Created on July 30, 2002, 2:36 PM
 */

package com.samspublishing.jpp.ch13;
import java.awt.*;
import java.awt.event.*;

/**
 *
 * @author  Stephen Potts
 * @version
 */
public class TestCheckboxGroups extends Frame implements ItemListener
{
   Checkbox cbWhiteBread;
   Checkbox cbWheatBread;
   Checkbox cbRyeBread;
   
   Checkbox cbToasted;
   
   TextField tField;
   
   /** Creates new TestCheckboxGroups */
   public TestCheckboxGroups()
   {
      CheckboxGroup cbgBread = new CheckboxGroup();
      cbWhiteBread = new Checkbox("White Bread", cbgBread, false);
      cbWhiteBread.addItemListener(this);
      
      cbWheatBread = new Checkbox("Wheat Bread", cbgBread, false);
      cbWheatBread.addItemListener(this);
      
      cbRyeBread = new Checkbox("Rye Bread", cbgBread, false);
      cbRyeBread.addItemListener(this);

      cbToasted= new Checkbox("Toasted");
      cbToasted.setState(false);
      cbToasted.addItemListener(this);
      
      tField = new TextField(30);

      
      setLayout(new FlowLayout());
      add(cbWhiteBread);
      add(cbWheatBread);
      add(cbRyeBread);

      add(cbToasted);
      add(tField);
      
      addWindowListener(new WinCloser());
      setTitle("Using Checkboxes");
      setBounds( 100, 100, 300, 300);
      setVisible(true);
   }
   
   public void itemStateChanged(ItemEvent ie)
   {
      Checkbox cb = (Checkbox)ie.getItemSelectable();
      if( cb.getState())
         tField.setText(cb.getLabel());
      else
         tField.setText("Not " + cb.getLabel());

   }
   
   public static void main(String[] args)
   {
      TestCheckboxGroups tcb = new TestCheckboxGroups();
   }
   
}

class WinCloser extends WindowAdapter
{
   public void windowClosing(WindowEvent e)
   {
      System.exit(0);
   }
}