www.pudn.com > ANButton.zip > ANButton.java
/*
ANButton.java
Version 1.0.0
"Written" by Florian Hars, 14-FEB-1996.
ANButton.class loads up to 10 images. Images 3 to 9 are dispayed in a
sequence when the pointer in located over the button, image0 (if
present) is the normal apperance, image1 is the Background and image2
is the depressed button. The parameters image1, image2 and image3 are
required.
"Writing" it means adding a thread taken from the Animator.java-example to:
BFButton.java
Version 1.0.0
Written by Elijah Dean Meeker 1/4/96
BFButton.class(stands for Background/Foreground)is an preloading interactive
button that loads two or three images (based on whether or not image0 is a
parameter) and a background image. Clicking it navigates to the given URL. It
uses off-screen buffering to avoid flicker. Here are two valid applet tags:
Two states:
Three states:
Please feel free to use and improve this code. It would not be here but for the
freely given help of others. I would love to see your improvements.
Elijah.
elijah@bga.com
http://www.realtime.net/~elijah/
The same things are valid for me.
Florian.
hars@math.uni-hamburg.de
http://www.math.uni-hamburg.de/~fm5a014 */
import java.awt.* ;
//import java.awt.Graphics;
//import java.awt.Event;
//import java.awt.Image;
import java.awt.MediaTracker;
import java.net.URL;
import java.net.MalformedURLException;
import java.lang.InterruptedException;
import java.applet.Applet;
public class ANButton extends java.applet.Applet implements Runnable{
private MediaTracker tracker;
private Image buf;
private Image bg;
private Image img[] = new Image[10];
private int X,Y;
private Graphics offscreen;
private Dimension d;
private boolean onButt = false;
private boolean pressedButt = false;
private boolean three_state = true;
private boolean userPause = true;
private int onIs = 0;
private int animImg = 3;
private int maxImg = 3;
private int pause = 200;
private URL clickDest;
private String dest;
private String destDefault = "http://www.math.uni-hamburg.de/math/ign/";
/**
* The thread animating the images.
*/
private Thread engine = null;
/****************************STATE CHANGES*************************************/
public void init() {
String istr;
d = size();
buf= createImage(d.width,d.height);
offscreen = buf.getGraphics();
int i = 0;
boolean finished = false;
tracker = new MediaTracker(this);
while (!finished && i<10) {
istr = getParameter("image"+i);
if (istr == null){
if(i>0){
finished = true;
}else{
three_state = false;
onIs = 3;
}
}else{
if (i==0) {
three_state = true;
}
showStatus("Loading image "+istr+".");
img[i] = getImage(getCodeBase(),istr);
tracker.addImage(img[i], 0);
try {
tracker.waitForAll();
} catch (InterruptedException e) {
System.out.println("Error waiting for image"+i+" to load");
}//end catch
}//end if
i++;
}//end while
maxImg = i-2;
if (maxImg < 3) {
System.out.println("Need at least images 1 to 3: Check Applet Tag.");
for (i = maxImg + 1; i < 4 ; i++) {
img[i]=img[1];
}
maxImg = 3;
}
istr = getParameter("x");
X = (istr != null) ? Integer.parseInt(istr) : 0;
istr = getParameter("y");
Y = (istr != null) ? Integer.parseInt(istr) : 0;
istr = getParameter("pause");
pause = (istr != null) ? Integer.parseInt(istr) : 200;
istr = getParameter("dest");
dest = (istr != null) ? istr : destDefault;
try{
clickDest = new URL(dest);
}catch(MalformedURLException mal){
System.out.println("Malformed URL: Check Applet Tag.");
}
}//end init
public void start(){
if (engine == null && !userPause) {
engine = new Thread(this);
engine.start();
}
}//end start
public void stop(){
if (engine != null && engine.isAlive()) {
engine.stop();
}
engine = null;
}//end stop
public void destroy(){
}//end destroy
/****************************END STATE CHANGES********************************/
/*******************************EVENTS****************************************/
public boolean mouseDown(Event e, int x, int y){
if (engine != null && engine.isAlive()) {
userPause = true;
engine.suspend();
stopPlaying();
}
pressedButt = true;
repaint();
return(true);
}//end mouseDown
public boolean mouseUp(Event e, int x, int y){
if(pressedButt && onButt){
pressedButt = false;
repaint();
getAppletContext().showDocument(clickDest);
}else{
pressedButt = false;
repaint();
}
return(true);
}//end mouseUp
public boolean mouseEnter(Event e, int x, int y){
onButt = true;
userPause = false;
if (engine != null && engine.isAlive()) {
engine.resume();
startPlaying();
} else {
engine = new Thread(this);
engine.start();
startPlaying();
}
repaint();
showStatus(dest);
return(true);
}//end mouseEnter
public boolean mouseExit(Event e, int x, int y){
onButt = false;
userPause= true;
if (engine != null && engine.isAlive()) {
engine.suspend();
stopPlaying();
}
repaint();
showStatus("");
return(true);
}//end mouseExit
/*******************************END EVENTS*************************************/
/*******************************METHODS****************************************/
void startPlaying() {
}
void stopPlaying() {
}
public void run() {
Thread me = Thread.currentThread();
me.setPriority(Thread.MIN_PRIORITY);
while (engine == me) {
try {
Thread.sleep(pause);
} catch (InterruptedException e) {
// Should we do anything?
}
animImg += 1;
if (animImg > maxImg) {
animImg=3;
}
repaint();
}
}
public void update(Graphics g){
if(!onButt) {
if(three_state) {
onIs = 0;
} else {
onIs = 3;
}
}
else if (onButt && !pressedButt) {
onIs = 3;
}
else {
onIs = 2;
}
paint(g);
}//end update
public void paint(Graphics g){
if (offscreen != null) {
paintApplet(offscreen);
g.drawImage(buf, 0, 0, this);
} else {
paintApplet(g);
}
}//end paint
public void paintApplet(Graphics g) {
int pic;
pic = onIs;
if (onIs == 3) {
pic = animImg;
}
g.drawImage(img[1],0,0,null);
g.drawImage(img[pic],X,Y,null);
}
/*****************************END METHODS**************************************/
}//end class ANButton