error with WindowListener
i want a JOptionPane To appear When The User Exists The Program
on the following code:
import java.awt.*;
import javax.swing.*;
import javax.swing.JOptionPane;
import java.awt.event.ActionEvent;
import javax.swing.JPanel;
import javax.swing.JFrame;
import java.awt.event.*;
publicclass MyFrameextends JFrame
{
JLabel label=new JLabel("Hello");
MyInner inner;
MyFrame ()
{
setupGUI();
}
privatevoid setupGUI()
{
JFrame f =new JFrame();
f.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
f.setTitle("Window Event");
f.setSize(550,350);
f.setResizable(false);
f.setLayout(new BorderLayout());
f.add("Center",label);
f.show(true);
inner=new MyInner();
f.addWindowListener(inner);
}
class MyInnerimplements WindowListener
{
publicvoid windowClosed(WindowEvent e)
{
JOptionPane.showMessageDialog(null,"Thanks God! " );
}
}
publicstaticvoid main(String[]args)
{
MyFrame frame=new MyFrame ();
}
}
i have an error:
MyFrame.MyInner is not abstract and does not override abstract method windowDeactivated(java.awt.event.WindowEvent) in java.awt.event.WindowListener
how do i fix it?
thank you
Your inner class implements WindowListener, so it must implement all seven methods in the WindowListener interface.
http://java.sun.com/j2se/1.5.0/docs/api/java/awt/event/WindowListener.html
You could simply do this for the rest of the methods:
public void windowActivated(WindowEvent e) { }
Or you could make your inner class extends WindowAdapter so you aren't forced to implement methods you don't need.
ok.when i added windowAdapter to the inner class
it gave me an error:'}' expected
why?and how it is fixed?
thank you
import java.awt.*;
import javax.swing.*;
import javax.swing.JOptionPane;
import java.awt.event.WindowListener;
import java.awt.event.WindowEvent;
import javax.swing.JPanel;
import javax.swing.JFrame;
import java.awt.event.*;
public class MyFrame extends JFrame
{
JLabel label=new JLabel("Hello");
MyInner inner;
MyFrame ()
{
setupGUI();
}
private void setupGUI()
{
JFrame f =new JFrame();
f.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);
f.setTitle("Window Event");
f.setSize(550,350);
f.setResizable(false);
f.setLayout(new BorderLayout());
f.add("Center",label);
f.show(true);
inner=new MyInner();
f.addWindowListener(inner);
}
class MyInner implements WindowListener extends WindowAdapter
{
public void windowClosed(WindowEvent e)
{
JOptionPane.showMessageDialog(null, "Thanks God! " );
}
}
public static void main(String[]args)
{
MyFrame frame=new MyFrame ();
}
}
