// This example is from _Java Examples in a Nutshell_. (http://www.oreilly.com)
// Copyright (c) 1997 by David Flanagan
// This example is provided WITHOUT ANY WARRANTY either expressed or implied.
// You may study, use, modify, and distribute it for non-commercial purposes.
// For any commercial use, see http://www.davidflanagan.com/javaexamples
import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
/** A program that displays all the event that occur in its window */
public class EventTester2 extends Frame
{
/** The main method: create an EventTester frame, and pop it up */
public static void main(String[] args) {
EventTester2 et = new EventTester2();
et.setSize(500, 400);
et.show();
}
/** The constructor: register the event types we are interested in */
public EventTester2() {
super("Event Tester");
this.enableEvents(AWTEvent.MOUSE_EVENT_MASK |
AWTEvent.MOUSE_MOTION_EVENT_MASK |
AWTEvent.KEY_EVENT_MASK |
AWTEvent.FOCUS_EVENT_MASK |
AWTEvent.COMPONENT_EVENT_MASK |
AWTEvent.WINDOW_EVENT_MASK);
}
/**
* Display mouse events that don't involve mouse motion.
* The mousemods() method prints modifiers, and is defined below.
* The other methods return additional information about the mouse event.
* showLine() displays a line of text in the window. It is defined
* at the end of this class, along with the paint() method.
*/
public void processMouseEvent(MouseEvent e) {
String type = null;
switch(e.getID()) {
case MouseEvent.MOUSE_PRESSED: type = "MOUSE_PRESSED"; break;
case MouseEvent.MOUSE_RELEASED: type = "MOUSE_RELEASED"; break;
case MouseEvent.MOUSE_CLICKED: type = "MOUSE_CLICKED"; break;
case MouseEvent.MOUSE_ENTERED: type = "MOUSE_ENTERED"; break;
case MouseEvent.MOUSE_EXITED: type = "MOUSE_EXITED"; break;
}
showLine(mousemods(e) + type + ": [" + e.getX() + "," + e.getY() + "] " +
"num clicks = " + e.getClickCount() +
(e.isPopupTrigger()?"; is popup trigger":""));
}
/**
* Display mouse moved and dragged mouse event. Note that MouseEvent
* is the only event type that has two methods, two EventListener interfaces
* and two adapter classes to handle two distinct categories of events.
* Also, as seen in init(), mouse motion events must be requested
* separately from other mouse event types.
*/
public void processMouseMotionEvent(MouseEvent e) {
String type = null;
switch(e.getID()) {
case MouseEvent.MOUSE_MOVED: type = "MOUSE_MOVED"; break;
case MouseEvent.MOUSE_DRAGGED: type = "MOUSE_DRAGGED"; break;
}
showLine(mousemods(e) + type + ": [" + e.getX() + "," + e.getY() + "] " +
"num clicks = " + e.getClickCount() +
(e.isPopupTrigger()?"; is popup trigger":""));
}
/** Return a string representation of the modifiers for a MouseEvent.
* Note that the methods called here are inherited from InputEvent.
*/
protected String mousemods(MouseEvent e) {
int mods = e.getModifiers();
String s = "";
if (e.isShiftDown()) s += "Shift ";
if (e.isControlDown()) s += "Ctrl ";
if ((mods & InputEvent.BUTTON1_MASK) != 0) s += "Button 1 ";
if ((mods & InputEvent.BUTTON2_MASK) != 0) s += "Button 2 ";
if ((mods & InputEvent.BUTTON3_MASK) != 0) s += "Button 3 ";
return s;
}
/**
* Display keyboard events.
* Note that there are three distinct types of key events, and that
* key events are reported by key code and/or Unicode character.
* KEY_PRESSED and KEY_RELEASED events are generated for all key strokes.
* KEY_TYPED events are only generated when a key stroke produces a
* Unicode character; these events do not report a key code.
* If isActionKey() returns true, then the key event reports only
* a key code, because the key that was pressed or released (such as a
* function key) has no corresponding Unicode character.
* Key codes can be interpreted by using the many VK_ constants defined
* by the KeyEvent class, or they can be converted to strings using
* the static getKeyText() method as we do here.
*/
public void processKeyEvent(KeyEvent e) {
String eventtype, modifiers, code, character;
switch(e.getID()) {
case KeyEvent.KEY_PRESSED: eventtype = "KEY_PRESSED"; break;
case KeyEvent.KEY_RELEASED: eventtype = "KEY_RELEASED"; break;
case KeyEvent.KEY_TYPED: eventtype = "KEY_TYPED"; break;
default: eventtype = "UNKNOWN";
}
// Convert the list of modifier keys to a string
modifiers = KeyEvent.getKeyModifiersText(e.getModifiers());
// Get string and numeric versions of the key code, if any.
if (e.getID() == KeyEvent.KEY_TYPED) code = "";
else code = "Code=" + KeyEvent.getKeyText(e.getKeyCode()) +
" (" + e.getKeyCode() + ")";
// Get string and numeric versions of the Unicode character, if any.
if (e.isActionKey()) character = "";
else character = "Character=" + e.getKeyChar() +
" (Unicode=" + ((int)e.getKeyChar()) + ")";
// Display it all.
showLine(eventtype + ": " + modifiers + " " + code + " " + character);
}
/** Display keyboard focus events. Focus can be permanently
* gained or lost, or temporarily transferred to or from a component. */
public void processFocusEvent(FocusEvent e) {
if (e.getID() == FocusEvent.FOCUS_GAINED)
showLine("FOCUS_GAINED" + (e.isTemporary()?" (temporary)":""));
else
showLine("FOCUS_LOST" + (e.isTemporary()?" (temporary)":""));
}
/** Display Component events. */
public void processComponentEvent(ComponentEvent e) {
switch(e.getID()) {
case ComponentEvent.COMPONENT_MOVED: showLine("COMPONENT_MOVED"); break;
case ComponentEvent.COMPONENT_RESIZED: showLine("COMPONENT_RESIZED");break;
case ComponentEvent.COMPONENT_HIDDEN: showLine("COMPONENT_HIDDEN"); break;
case ComponentEvent.COMPONENT_SHOWN: showLine("COMPONENT_SHOWN"); break;
}
}
/** Display Window events. Note the special handling of WINDOW_CLOSING */
public void processWindowEvent(WindowEvent e) {
switch(e.getID()) {
case WindowEvent.WINDOW_OPENED: showLine("WINDOW_OPENED"); break;
case WindowEvent.WINDOW_CLOSED: showLine("WINDOW_CLOSED"); break;
case WindowEvent.WINDOW_CLOSING: showLine("WINDOW_CLOSING"); break;
case WindowEvent.WINDOW_ICONIFIED: showLine("WINDOW_ICONIFIED"); break;
case WindowEvent.WINDOW_DEICONIFIED: showLine("WINDOW_DEICONIFIED"); break;
case WindowEvent.WINDOW_ACTIVATED: showLine("WINDOW_ACTIVATED"); break;
case WindowEvent.WINDOW_DEACTIVATED: showLine("WINDOW_DEACTIVATED"); break;
}
// If the user requested a window close, quit the program.
// But first display a message, force it to be visible, and make
// sure the user has time to read it.
if (e.getID() == WindowEvent.WINDOW_CLOSING) {
showLine("WINDOW_CLOSING event received.");
showLine("Application will exit in 5 seconds");
update(this.getGraphics());
try {Thread.sleep(5000);} catch (InterruptedException ie) { ; }
System.exit(0);
}
}
/** The list of lines to display in the window */
protected Vector lines = new Vector();
/** Add a new line to the list of lines, and redisplay */
protected void showLine(String s) {
if (lines.size() == 20) lines.removeElementAt(0);
lines.addElement(s);
repaint();
}
/** This method repaints the text in the window */
public void paint(Graphics g) {
for(int i = 0; i < lines.size(); i++)
g.drawString((String)lines.elementAt(i), 20, i*16 + 50);
}
}
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