How To Create CheckBox In Java

Introduction

 

In this article, we discuss how to create a checkbox in Java.

 

What is checkbox?

 

Simply called a selection box, a checkbox is a type of square box where the user can click to select their choice. Using a checkbox he can select multiple values at a time.

 

The following figure shows some sample checkboxes:

 

 

Example

 

In this example; we create four checkboxes to select the colors of our choice. Now for creating checkboxes we use AWT (Abstract Window Toolkit) and Swing components.

 

Procedure to follow

 

Step 1: We create four checkboxes to provide the user with a choice of selecting multiple choices.

JPanel overallGUI = new JPanel();
JPanel chkBxPanl = new JPanel();
chkBxPanl.setLayout(new BoxLayout(chkBxPanl, BoxLayout.PAGE_AXIS));
chkBxPanl.add(Box.createRigidArea(new Dimension(15,5)));
redbtn = new JCheckBox("Red color");
redbtn.setSelected(true);
chkBxPanl.add(redbtn);
chkBxPanl.add(Box.createHorizontalGlue());
bluebtn = new JCheckBox("Blue color");
chkBxPanl.add(bluebtn);
chkBxPanl.add(Box.createHorizontalGlue());
greenbtn = new JCheckBox("Green color");
chkBxPanl.add(greenbtn);
chkBxPanl.add(Box.createHorizontalGlue());
yellowbtn = new JCheckBox("Yellow color");
chkBxPanl.add(yellowbtn);
chkBxPanl.add(Box.createRigidArea(new Dimension(15, 5)));

Step 2: Now we create a simple Panel to display all the four checkboxes we created.

JPanel bxPanl = new JPanel(new GridLayout(3, 3, 23, 23));
JPanel redBx = squrPanl(Color.red, 55);
JPanel blBx = squrPanl(Color.blue, 55);
JPanel grnBx = squrPanl(Color.green, 55);
JPanel yelwBx = squrPanl(Color.yellow, 55);

Step 3: Now we hide all the boxes except the red button.

grnBx.setVisible(false);
blBx.setVisible(false);
yelwBx.setVisible(false);
bxPanl.add(redBx);
bxPanl.add(blBx);
bxPanl.add(grnBx);
bxPanl.add(yelwBx);
overallGUI.add(chkBxPanl);
overallGUI.add(bxPanl);
overallGUI.setOpaque(true);
return overallGUI;

Step 4: Now we create a square panel and set their bounds.

private JPanel squrPanl(Color color, int size)
{
    JPanel temporaryPanl = new JPanel();
    temporaryPanl.setBackground(color);
    temporaryPanl.setMinimumSize(new Dimension(size, size));
    temporaryPanl.setMaximumSize(new Dimension(size, size));
    temporaryPanl.setPreferredSize(new Dimension(size, size));
    return temporaryPanl;
}
private static void showGUI()
{
    JFrame.setDefaultLookAndFeelDecorated(true);
    JFrame frm = new JFrame("CheckBox");
    SwingCheckBxEx showdemo = new SwingCheckBxEx();
    frm.setContentPane(showdemo.shwCreatPnl());
    frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frm.pack();
    frm.setVisible(true);
}
public static void main(String[] args)
{
    SwingUtilities.invokeLater(new Runnable()
        {
            public void run()
            {
                showGUI();
            }
        });
}

Complete code

 

SwingCheckBxEx.java

import java.awt.*;
import javax.swing.*;
import java.awt.Color;
public class SwingCheckBxEx
{
    JCheckBox redbtn, bluebtn, greenbtn, yellowbtn;
    public JPanel shwCreatPnl()
    {
        JPanel overallGUI = new JPanel();
        JPanel chkBxPanl = new JPanel();
        chkBxPanl.setLayout(new BoxLayout(chkBxPanl, BoxLayout.PAGE_AXIS));
        chkBxPanl.add(Box.createRigidArea(new Dimension(15, 5)));
        redbtn = new JCheckBox("Red color");
        redbtn.setSelected(true);
        chkBxPanl.add(redbtn);
        chkBxPanl.add(Box.createHorizontalGlue());
        bluebtn = new JCheckBox("Blue color");
        chkBxPanl.add(bluebtn);
        chkBxPanl.add(Box.createHorizontalGlue());
        greenbtn = new JCheckBox("Green color");
        chkBxPanl.add(greenbtn);
        chkBxPanl.add(Box.createHorizontalGlue());
        yellowbtn = new JCheckBox("Yellow color");
        chkBxPanl.add(yellowbtn);
        chkBxPanl.add(Box.createRigidArea(new Dimension(15, 5)));
        JPanel bxPanl = new JPanel(new GridLayout(3, 3, 23, 23));
        JPanel redBx = squrPanl(Color.red, 55);
        JPanel blBx = squrPanl(Color.blue, 55);
        JPanel grnBx = squrPanl(Color.green, 55);
        JPanel yelwBx = squrPanl(Color.yellow, 55);
        grnBx.setVisible(false);
        blBx.setVisible(false);
        yelwBx.setVisible(false);
        bxPanl.add(redBx);
        bxPanl.add(blBx);
        bxPanl.add(grnBx);
        bxPanl.add(yelwBx);
        overallGUI.add(chkBxPanl);
        overallGUI.add(bxPanl);
        overallGUI.setOpaque(true);
        return overallGUI;
    }
    private JPanel squrPanl(Color color, int size)
    {
        JPanel temporaryPanl = new JPanel();
        temporaryPanl.setBackground(color);
        temporaryPanl.setMinimumSize(new Dimension(size, size));
        temporaryPanl.setMaximumSize(new Dimension(size, size));
        temporaryPanl.setPreferredSize(new Dimension(size, size));
        return temporaryPanl;
    }
    private static void showGUI()
    {
        JFrame.setDefaultLookAndFeelDecorated(true);
        JFrame frm = new JFrame("CheckBox");
        SwingCheckBxEx showdemo = new SwingCheckBxEx();
        frm.setContentPane(showdemo.shwCreatPnl());
        frm.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frm.pack();
        frm.setVisible(true);
    }
    public static void main(String[] args)
    {
        SwingUtilities.invokeLater(new Runnable()
            {
                public void run()
                {
                    showGUI();
                }
            });
    }
}

Output