/* From http://java.sun.com/docs/books/tutorial/index.html */
/*
* Copyright (c) 2006 Sun Microsystems, Inc. All Rights Reserved.
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* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* -Redistribution of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* -Redistribution 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, Inc. or the names of contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* This software is provided "AS IS," without a warranty of any kind. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
* ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
* OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MIDROSYSTEMS, INC. ("SUN")
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/*
* KeyEventDemo.java is a 1.4 example that requires no other files.
*/
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;
public class KeyEventDemo extends JPanel implements KeyListener, ActionListener {
JTextArea displayArea;
JTextField typingArea;
static final String newline = "\n";
public KeyEventDemo() {
super(new BorderLayout());
JButton button = new JButton("Clear");
button.addActionListener(this);
typingArea = new JTextField(20);
typingArea.addKeyListener(this);
//Uncomment this if you wish to turn off focus
//traversal. The focus subsystem consumes
//focus traversal keys, such as Tab and Shift Tab.
//If you uncomment the following line of code, this
//disables focus traversal and the Tab events will
//become available to the key event listener.
//typingArea.setFocusTraversalKeysEnabled(false);
displayArea = new JTextArea();
displayArea.setEditable(false);
JScrollPane scrollPane = new JScrollPane(displayArea);
scrollPane.setPreferredSize(new Dimension(375, 125));
add(typingArea, BorderLayout.PAGE_START);
add(scrollPane, BorderLayout.CENTER);
add(button, BorderLayout.PAGE_END);
}
/** Handle the key typed event from the text field. */
public void keyTyped(KeyEvent e) {
displayInfo(e, "KEY TYPED: ");
}
/** Handle the key pressed event from the text field. */
public void keyPressed(KeyEvent e) {
displayInfo(e, "KEY PRESSED: ");
}
/** Handle the key released event from the text field. */
public void keyReleased(KeyEvent e) {
displayInfo(e, "KEY RELEASED: ");
}
/** Handle the button click. */
public void actionPerformed(ActionEvent e) {
//Clear the text components.
displayArea.setText("");
typingArea.setText("");
//Return the focus to the typing area.
typingArea.requestFocusInWindow();
}
/*
* We have to jump through some hoops to avoid trying to print non-printing
* characters such as Shift. (Not only do they not print, but if you put
* them in a String, the characters afterward won't show up in the text
* area.)
*/
protected void displayInfo(KeyEvent e, String s) {
String keyString, modString, tmpString, actionString, locationString;
//You should only rely on the key char if the event
//is a key typed event.
int id = e.getID();
if (id == KeyEvent.KEY_TYPED) {
char c = e.getKeyChar();
keyString = "key character = '" + c + "'";
} else {
int keyCode = e.getKeyCode();
keyString = "key code = " + keyCode + " ("
+ KeyEvent.getKeyText(keyCode) + ")";
}
int modifiers = e.getModifiersEx();
modString = "modifiers = " + modifiers;
tmpString = KeyEvent.getModifiersExText(modifiers);
if (tmpString.length() > 0) {
modString += " (" + tmpString + ")";
} else {
modString += " (no modifiers)";
}
actionString = "action key? ";
if (e.isActionKey()) {
actionString += "YES";
} else {
actionString += "NO";
}
locationString = "key location: ";
int location = e.getKeyLocation();
if (location == KeyEvent.KEY_LOCATION_STANDARD) {
locationString += "standard";
} else if (location == KeyEvent.KEY_LOCATION_LEFT) {
locationString += "left";
} else if (location == KeyEvent.KEY_LOCATION_RIGHT) {
locationString += "right";
} else if (location == KeyEvent.KEY_LOCATION_NUMPAD) {
locationString += "numpad";
} else { // (location == KeyEvent.KEY_LOCATION_UNKNOWN)
locationString += "unknown";
}
displayArea.append(s + newline + " " + keyString + newline + " "
+ modString + newline + " " + actionString + newline
+ " " + locationString + newline);
displayArea.setCaretPosition(displayArea.getDocument().getLength());
}
/**
* Create the GUI and show it. For thread safety, this method should be
* invoked from the event-dispatching thread.
*/
private static void createAndShowGUI() {
//Make sure we have nice window decorations.
JFrame.setDefaultLookAndFeelDecorated(true);
//Create and set up the window.
JFrame frame = new JFrame("KeyEventDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
//Create and set up the content pane.
JComponent newContentPane = new KeyEventDemo();
newContentPane.setOpaque(true); //content panes must be opaque
frame.setContentPane(newContentPane);
//Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
//Schedule a job for the event-dispatching thread:
//creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() {
public void run() {
createAndShowGUI();
}
});
}
}
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