How to have multiple listeners
/*
* Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
* All rights reserved. Software written by Ian F. Darwin and others.
* $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
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import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
/**
* Demo I wrote in response to a student request for how to have multiple
* listeners (Bobs) that are already on-screen added as listeners to a
* newly-created pushbutton (Fred).
*/
public class MultiListeners {
public static void main(String[] args) {
Bob b1 = new Bob();
b1.setVisible(true);
Bob b2 = new Bob();
b2.setVisible(true);
ActionListener[] bobs = { b1, b2 };
Fred f1 = new Fred(bobs);
f1.setVisible(true);
}
}
class Fred extends JFrame {
JButton okbutton = new JButton("OK");
public Fred(ActionListener[] bobs) {
getContentPane().add(okbutton);
for (int i = 0; i < bobs.length; i++) {
okbutton.addActionListener(bobs[i]);
}
}
}
class Bob extends JFrame implements ActionListener {
protected JLabel statusLabel = new JLabel(" ");
public Bob() {
getContentPane().add(statusLabel);
}
public void actionPerformed(ActionEvent e) {
statusLabel.setText("OK");
}
}
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