Java jcheckbox basic tutorial and examples
I can give you a basic tutorial and examples for using JCheckBox in Java.
JCheckBox is a class in the Java Swing package that provides a check box component. You can create a JCheckBox and add it to a JFrame or other container to allow the user to select or deselect it.
Here's an example of creating a simple JCheckBox:
import javax.swing.JCheckBox; import javax.swing.JFrame; public class MyCheckBox extends JFrame { public MyCheckBox() { super("Check Box Example"); JCheckBox checkBox = new JCheckBox("Check me!"); add(checkBox); pack(); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { new MyCheckBox(); } }
In this example, we create a new JFrame and add a JCheckBox to it with the label "Check me!". We then call the pack()
method to resize the JFrame to fit its contents, make it visible with setVisible(true)
, and set the default close operation to exit the application when the JFrame is closed.
When you run this program, it will display a window with a check box labeled "Check me!". By default, the check box will be unchecked.
Here's an example of reading the state of the check box:
import javax.swing.JCheckBox; import javax.swing.JFrame; import javax.swing.JOptionPane; public class MyCheckBox extends JFrame { public MyCheckBox() { super("Check Box Example"); JCheckBox checkBox = new JCheckBox("Check me!"); checkBox.addActionListener(e -> { if (checkBox.isSelected()) { JOptionPane.showMessageDialog(null, "Checkbox is checked!"); } else { JOptionPane.showMessageDialog(null, "Checkbox is not checked."); } }); add(checkBox); pack(); setVisible(true); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } public static void main(String[] args) { new MyCheckBox(); } }
In this example, we add an ActionListener to the check box using a lambda expression. The ActionListener reads the state of the check box using isSelected()
and displays a message dialog indicating whether the check box is checked or not.
Now, when you run the program and check or uncheck the box, it will display a message dialog with the appropriate text.
I hope this helps you get started with using JCheckBox in Java!