SaveDialog.java Source code

Introduction

Here is the source code for SaveDialog.java

Source

/*
 * 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.*;
import java.awt.event.*;
import javax.swing.*;

/*
 * Simple Save Dialog demo.
 * @version $Id: SaveDialog.java,v 1.4 2000/11/25 17:54:19 ian Exp $
 */
public class SaveDialog extends JFrame {
    boolean unsavedChanges = false;
    Button quitButton;

    /** "main program" method - construct and show */
    public static void main(String[] av) {
        // create a SaveDialog object, tell it to show up
        new SaveDialog().setVisible(true);
    }

    /** Construct the object including its GUI */
    public SaveDialog() {
        super("SaveDialog");
        Container cp = getContentPane();
        cp.setLayout(new FlowLayout());
        cp.add(new Label("Press this button to see the Quit dialog: "));
        cp.add(quitButton = new Button("Quit"));
        quitButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                System.out.println("In Exit Button's action handler");
                if (okToQuit()) {
                    setVisible(false);
                    dispose();
                    System.exit(0);
                }
            }
        });
        addWindowListener(new WindowAdapter() {
            public void windowClosing(WindowEvent e) {
                setVisible(false);
                dispose();
                System.exit(0);
            }
        });

        pack();
    }

    boolean okToQuit() {
        String[] choices = { "Yes, Save and Quit", "No, Quit without saving", "CANCEL" };
        int result = JOptionPane.showOptionDialog(this, "You have unsaved changes. Save before quitting?",
                "Warning", JOptionPane.YES_NO_CANCEL_OPTION, JOptionPane.WARNING_MESSAGE, null, choices,
                choices[0]);

        // Use of "null" as the Icon argument is contentious... the
        // document says you can pass null, but it does seem to
        // generate a lot of blather if you do, something about
        // a NullPointerException :-) ...

        if (result >= 0)
            System.out.println("You clicked " + choices[result]);

        switch (result) {
        case -1:
            System.out.println("You killed my die-alog - it died");
            return false;
        case 0: // save and quit
            System.out.println("Saving...");
            // mainApp.doSave();
            return true;
        case 1: // just quit
            return true;
        case 2: // cancel
            return false;
        default:
            throw new IllegalArgumentException("Unexpected return " + result);
        }
    }
}