windoweventdemo.java

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/*
 * Copyright (c) 1995 - 2008 Sun Microsystems, Inc.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - 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.
 *
 *   - Neither the name of Sun Microsystems nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
 */ 

package events;

/*
 * WindowEventDemo
 */

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

public class WindowEventDemo extends JFrame
        implements WindowListener,
        WindowFocusListener,
        WindowStateListener {
    static final String newline = System.getProperty("line.separator");
    static final  String space = "    ";
    static WindowEventDemo frame = new WindowEventDemo("WindowEventDemo");
    JTextArea display;
    
    public static void main(String[] args) {
        /* Use an appropriate Look and Feel */
        try {
            //UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
            //UIManager.setLookAndFeel("com.sun.java.swing.plaf.gtk.GTKLookAndFeel");
            UIManager.setLookAndFeel("javax.swing.plaf.metal.MetalLookAndFeel");
        } catch (UnsupportedLookAndFeelException ex) {
            ex.printStackTrace();
        } catch (IllegalAccessException ex) {
            ex.printStackTrace();
        } catch (InstantiationException ex) {
            ex.printStackTrace();
        } catch (ClassNotFoundException ex) {
            ex.printStackTrace();
        }
        /* Turn off metal's use of bold fonts */
        UIManager.put("swing.boldMetal", Boolean.FALSE);
        
        //Schedule a job for the event dispatch thread:
        //creating and showing this application's GUI.
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                createAndShowGUI();
            }
        });
    }
    
   /**
     * Create the GUI and show it.  For thread safety,
     * this method should be invoked from the
     * event-dispatching thread.
     */
    
    private static void createAndShowGUI() {
        //Create and set up the window.
        frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
        
        //Set up the content pane.
        frame.addComponentsToPane();
        
        //Display the window.
        frame.pack();
        frame.setVisible(true);
    }
    
    private void addComponentsToPane() {
        display = new JTextArea();
        display.setEditable(false);
        JScrollPane scrollPane = new JScrollPane(display);
        scrollPane.setPreferredSize(new Dimension(500, 450));
        getContentPane().add(scrollPane, BorderLayout.CENTER);
        
        addWindowListener(this);
        addWindowFocusListener(this);
        addWindowStateListener(this);
        
        checkWM();
    }
    
    public WindowEventDemo(String name) {
        super(name);
    }
    
    //Some window managers don't support all window states.
    public void checkWM() {
        Toolkit tk = frame.getToolkit();
        if (!(tk.isFrameStateSupported(Frame.ICONIFIED))) {
            displayMessage(
                    "Your window manager doesn't support ICONIFIED.");
        }  else displayMessage(
                "Your window manager supports ICONIFIED.");
        if (!(tk.isFrameStateSupported(Frame.MAXIMIZED_VERT))) {
            displayMessage(
                    "Your window manager doesn't support MAXIMIZED_VERT.");
        }  else displayMessage(
                "Your window manager supports MAXIMIZED_VERT.");
        if (!(tk.isFrameStateSupported(Frame.MAXIMIZED_HORIZ))) {
            displayMessage(
                    "Your window manager doesn't support MAXIMIZED_HORIZ.");
        } else displayMessage(
                "Your window manager supports MAXIMIZED_HORIZ.");
        if (!(tk.isFrameStateSupported(Frame.MAXIMIZED_BOTH))) {
            displayMessage(
                    "Your window manager doesn't support MAXIMIZED_BOTH.");
        } else {
            displayMessage(
                    "Your window manager supports MAXIMIZED_BOTH.");
        }
    }
    
    public void windowClosing(WindowEvent e) {
        displayMessage("WindowListener method called: windowClosing.");
        //A pause so user can see the message before
        //the window actually closes.
        ActionListener task = new ActionListener() {
            boolean alreadyDisposed = false;
            public void actionPerformed(ActionEvent e) {
                if (frame.isDisplayable()) {
                    alreadyDisposed = true;
                    frame.dispose();
                }
            }
        };
        Timer timer = new Timer(500, task); //fire every half second
        timer.setInitialDelay(2000);        //first delay 2 seconds
        timer.setRepeats(false);
        timer.start();
    }
    
    public void windowClosed(WindowEvent e) {
        //This will only be seen on standard output.
        displayMessage("WindowListener method called: windowClosed.");
    }
    
    public void windowOpened(WindowEvent e) {
        displayMessage("WindowListener method called: windowOpened.");
    }
    
    public void windowIconified(WindowEvent e) {
        displayMessage("WindowListener method called: windowIconified.");
    }
    
    public void windowDeiconified(WindowEvent e) {
        displayMessage("WindowListener method called: windowDeiconified.");
    }
    
    public void windowActivated(WindowEvent e) {
        displayMessage("WindowListener method called: windowActivated.");
    }
    
    public void windowDeactivated(WindowEvent e) {
        displayMessage("WindowListener method called: windowDeactivated.");
    }
    
    public void windowGainedFocus(WindowEvent e) {
        displayMessage("WindowFocusListener method called: windowGainedFocus.");
    }
    
    public void windowLostFocus(WindowEvent e) {
        displayMessage("WindowFocusListener method called: windowLostFocus.");
    }
    
    public void windowStateChanged(WindowEvent e) {
        displayStateMessage(
                "WindowStateListener method called: windowStateChanged.", e);
    }
    
    private void displayMessage(String msg) {
        display.append(msg + newline);
        System.out.println(msg);
    }
    
    private void displayStateMessage(String prefix, WindowEvent e) {
        int state = e.getNewState();
        int oldState = e.getOldState();
        String msg = prefix
                + newline + space
                + "New state: "
                + convertStateToString(state)
                + newline + space
                + "Old state: "
                + convertStateToString(oldState);
        displayMessage(msg);
    }
    
    private String convertStateToString(int state) {
        if (state == Frame.NORMAL) {
            return "NORMAL";
        }
        String strState = " ";
        if ((state & Frame.ICONIFIED) != 0) {
            strState += "ICONIFIED";
        }
        //MAXIMIZED_BOTH is a concatenation of two bits, so
        //we need to test for an exact match.
        if ((state & Frame.MAXIMIZED_BOTH) == Frame.MAXIMIZED_BOTH) {
            strState += "MAXIMIZED_BOTH";
        } else {
            if ((state & Frame.MAXIMIZED_VERT) != 0) {
                strState += "MAXIMIZED_VERT";
            }
            if ((state & Frame.MAXIMIZED_HORIZ) != 0) {
                strState += "MAXIMIZED_HORIZ";
            }
        }
        if (" ".equals(strState)){
            strState = "UNKNOWN";
        }
        return strState.trim();
    }
}