JLabel setText not updating text

Question

I am trying to update a JLabel by using the setText() method, but I can\'t redraw JLabel. Do I have to use the repaint() method to do that?

Answer 1

This simple example works for me so problem is not JLabel but some bug in other part of your source code. Please post full source code.

import java.awt.BorderLayout;
import java.awt.Button;
import java.awt.GridLayout;
import java.awt.Panel;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JFrame;
import javax.swing.JLabel;

public class Application {

public static void main(String[] args) {
    JFrame frame = new JFrame("JLabel test");
    frame.setVisible(true);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


    Panel p = new Panel();
    p.setLayout(new GridLayout());

    Button button = new Button("Change");
    final JLabel label = new JLabel(Long.toString(Long.MAX_VALUE));

    button.addActionListener(new ActionListener() {
        @Override
        public void actionPerformed(ActionEvent e) {
            label.setText(Long.toString(e.getWhen()));
        }
    });

    p.add(button);
    p.add(label);
    frame.add(p, BorderLayout.NORTH);
    frame.pack();

}
}