JCheckBox
- A JCheckBox can extend JToggleButton and it can be a small box that is either checked or unchecked.
- When we click on a JCheckBox, it changes from checked to unchecked or vice versa automatically.
- A JCheckBox can generate an ActionListener or an ItemListener whenever the checkbox is changed.
- An isSelected() method is used to test if a checkbox is checked or not.
- By default, we can select all the checkbox items at a time, if we want to select only one item at a time by using ButtonGroup class.
Example
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class JCheckBoxGroupTest extends JFrame {
private ButtonGroup checkBoxGroup;
private JCheckBox jcb1, jcb2, jcb3;
private JPanel panel;
public JCheckBoxGroupTest() {
super("JCheckBoxGroup Test");
panel = new JPanel(new GridLayout(3,0));
jcb1 = new JCheckBox("India", true);
jcb2 = new JCheckBox("England", false);
jcb3 = new JCheckBox("Australia", false);
checkBoxGroup = new ButtonGroup();
//add CheckBoxes to ButtonGroup
checkBoxGroup.add(jcb1);
checkBoxGroup.add(jcb2);
checkBoxGroup.add(jcb3);
panel.add(jcb1);
panel.add(jcb2);
panel.add(jcb3);
add(panel);
setSize(375, 250);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
setVisible(true);
}
public static void main(String args[]) {
new JCheckBoxGroupTest();
}
}
Output
