Demonstrate a listener being reused
/*
* 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 $
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer. 2. Redistributions in
* binary form must reproduce the above copyright notice, this list of
* conditions and the following disclaimer in the documentation and/or other
* materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Java, the Duke mascot, and all variants of Sun's Java "steaming coffee cup"
* logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
* pioneering role in inventing and promulgating (and standardizing) the Java
* language and environment is gratefully acknowledged.
*
* The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
* inventing predecessor languages C and C++ is also gratefully acknowledged.
*/
import java.awt.Button;
import java.awt.Frame;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class ListenerReuse extends Frame {
public ListenerReuse() {
Button b = new Button("Save");
add(b);
MenuBar mb = new MenuBar();
setMenuBar(mb);
Menu fm = new Menu("File");
mb.add(fm);
MenuItem mi = new MenuItem("Save");
fm.add(mi);
// Construct the ActionListener, and keep a reference to it.
ActionListener saver = new ActionListener() {
public void actionPerformed(ActionEvent e) {
System.out.println("Saving your file...");
// In real life we would call the doSave() method
// in the main class, something like this:
// mainProg.doSave();
}
};
// Register the actionListener with the Button
b.addActionListener(saver);
// And now register the same actionListener with the MenuItem
mi.addActionListener(saver);
pack();
}
/** Main just calls the above */
public static void main(String[] a) {
ListenerReuse lr = new ListenerReuse();
lr.setVisible(true);
}
}
Related examples in the same category
