CIS 260 TestToggleButtons.java

Code

/*
    TestToggleButtons.java
    David Klick
    CIS 260
    2006-02-14

    Demonstrates use of JCheckBoxes and JRadioButtons.
*/

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class TestToggleButtons extends JFrame {

    JCheckBox chk1, chk2;
    JRadioButton rdo1, rdo2;
    ButtonGroup grp;
    JLabel lblOut;

    public static void main(String[] args) {
        TestToggleButtons app = new TestToggleButtons("Toggle Button Test");
    }

    public TestToggleButtons() { this(""); }
    public TestToggleButtons(String title) { super(title); init(); }

    private void init() {
        // make Window shut down graphics thread properly
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        // get content pane and set to GridLayout
        Container c = getContentPane();
        c.setLayout(new GridLayout(3, 1, 20, 5));

        // create widgets
        lblOut = new JLabel();
        chk1 = new JCheckBox("Option 1");
        chk2 = new JCheckBox("Option 2", true);
        rdo1 = new JRadioButton("Red", true);
        rdo2 = new JRadioButton("Blue");

        // create group to make radio buttons work properly
        grp = new ButtonGroup();
        grp.add(rdo1);
        grp.add(rdo2);

        // create panels for rows where needed
        JPanel pnlTop = new JPanel();
        JPanel pnlCenter = new JPanel();
        pnlTop.setLayout(new GridLayout(1,2));
        pnlCenter.setLayout(new GridLayout(1,2));

        // add widgets to panels and then content pane
        pnlTop.add(chk1);
        pnlTop.add(chk2);
        pnlCenter.add(rdo1);
        pnlCenter.add(rdo2);
        c.add(pnlTop);
        c.add(pnlCenter);
        c.add(lblOut);

        // create and add event handlers (listeners)
        MyRadioListener rdoLstnr = new MyRadioListener();
        MyCheckListener chkLstnr = new MyCheckListener();
        rdo1.addActionListener(rdoLstnr);
        rdo2.addActionListener(rdoLstnr);
        chk1.addActionListener(chkLstnr);
        chk2.addActionListener(chkLstnr);

        // make it live
        setSize(200, 100);
        setVisible(true);
    }

    class MyRadioListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String s = "You picked radio button #";
            if (e.getSource() == rdo1) s += "1: " + e.getActionCommand();
            else s += "2: " + e.getActionCommand();
            lblOut.setText(s);
        }
    }

    class MyCheckListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String s = "You picked checkbox #";
            if (e.getSource() == chk1) s += "1: " + e.getActionCommand();
            else s += "2: " + e.getActionCommand();
            lblOut.setText(s);
        }
    }
}