// 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.util.*;
/** An applet that gives details about Java 1.0 events */
public class EventTester1 extends Applet {
// Handle mouse events
public boolean mouseDown(Event e, int x, int y) {
showLine(mods(e.modifiers) + "Mouse Down: [" + x + "," + y + "]");
return true;
}
public boolean mouseUp(Event e, int x, int y) {
showLine(mods(e.modifiers) + "Mouse Up: [" + x + "," + y + "]");
return true;
}
public boolean mouseDrag(Event e, int x, int y) {
showLine(mods(e.modifiers) + "Mouse Drag: [" + x + "," + y + "]");
return true;
}
public boolean mouseMove(Event e, int x, int y) {
showLine(mods(e.modifiers) + "Mouse Move: [" + x + "," + y + "]");
return true;
}
public boolean mouseEnter(Event e, int x, int y) {
showLine("Mouse Enter: [" + x + "," + y + "]"); return true;
}
public boolean mouseExit(Event e, int x, int y) {
showLine("Mouse Exit: [" + x + "," + y + "]"); return true;
}
// Handle focus events
public boolean gotFocus(Event e, Object what) {
showLine("Got Focus"); return true;
}
public boolean lostFocus(Event e, Object what) {
showLine("Lost Focus"); return true;
}
// Handle key down and key up events
// This gets more confusing because there are two types of key events
public boolean keyDown(Event e, int key) {
int flags = e.modifiers;
if (e.id == Event.KEY_PRESS) // a regular key
showLine("Key Down: " + mods(flags) + key_name(e));
else if (e.id == Event.KEY_ACTION) // a function key
showLine("Function Key Down: " + mods(flags) + function_key_name(key));
return true;
}
public boolean keyUp(Event e, int key) {
int flags = e.modifiers;
if (e.id == Event.KEY_RELEASE) // a regular key
showLine("Key Up: " + mods(flags) + key_name(e));
else if (e.id == Event.KEY_ACTION_RELEASE) // a function key
showLine("Function Key Up: " + mods(flags) + function_key_name(key));
return true;
}
// The remaining methods help us sort out the various modifiers and keys
// Return the current list of modifier keys
private String mods(int flags) {
String s = "[ ";
if (flags == 0) return "";
if ((flags & Event.SHIFT_MASK) != 0) s += "Shift ";
if ((flags & Event.CTRL_MASK) != 0) s += "Control ";
if ((flags & Event.META_MASK) != 0) s += "Meta ";
if ((flags & Event.ALT_MASK) != 0) s += "Alt ";
s += "] ";
return s;
}
// Return the name of a regular (non-function) key.
private String key_name(Event e) {
char c = (char) e.key;
if (e.controlDown()) { // If CTRL flag is set, handle control chars.
if (c < ' ') {
c += '@';
return "^" + c;
}
}
else { // If CTRL flag is not set, then certain ASCII
switch (c) { // control characters have special meaning.
case '\n': return "Return";
case '\t': return "Tab";
case '\033': return "Escape";
case '\010': return "Backspace";
}
}
// Handle the remaining possibilities.
if (c == '\177') return "Delete";
else if (c == ' ') return "Space";
else return String.valueOf(c);
}
// Return the name of a function key. Just compare the key to the
// constants defined in the Event class.
private String function_key_name(int key) {
switch(key) {
case Event.HOME: return "Home"; case Event.END: return "End";
case Event.PGUP: return "Page Up"; case Event.PGDN: return "Page Down";
case Event.UP: return "Up"; case Event.DOWN: return "Down";
case Event.LEFT: return "Left"; case Event.RIGHT: return "Right";
case Event.F1: return "F1"; case Event.F2: return "F2";
case Event.F3: return "F3"; case Event.F4: return "F4";
case Event.F5: return "F5"; case Event.F6: return "F6";
case Event.F7: return "F7"; case Event.F8: return "F8";
case Event.F9: return "F9"; case Event.F10: return "F10";
case Event.F11: return "F11"; case Event.F12: return "F12";
}
return "Unknown Function Key";
}
/** A 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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