need this to change to random colors every .8 secs. compiles ok, but not getting wanted results. cant figure out where i am wrong?
i get the applet viewer window with a black square but no color change.
Here is the .html file
<applet code = ColorChange .class width = 300 height = 300>
</applet>
import java.applet.*;
import java.awt.*;
public class ColorChange extends Applet {
Color c;
boolean done;
public void start() {
done = false;
Thread t = new Thread();
// start thread countdown
t.start();
}
public void stop() {
done = true;
}
public void paint(Graphics g) {
super.paint(g);
g.fillRect(100,100,130,130);
}
public void run(){
while(! done) {
c = new Color((int)(255*Math.random()),
(int)(255*Math.random()),
(int)(255*Math.random()));
this.setForeground(c);
try {
Thread.sleep(800); // sleep for .8 sec
}
catch(InterruptedException e) { } // ignore interuptions
}
}
}
Axn,
I wouldn't sleep the Thread, I would use a timer to instance the events to fire a repaint().
Here is the working code with comments to help you learn what is going on:
import java.applet.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Timer;
public class DaniProject extends Applet {
Color c; // Start off black
// Applets require the init() method like normal applications require the main() method.
public void init(){
Timer timer = new Timer(800, new TimerHandler()); // Here we will instantiate a timer with
// 800 MS delay (.8s) and register a new actionlistener for the
// tick events.
timer.start(); // Start the timer and fire an event.
}
// On the timer events we will create a new color and repaint the window.
private class TimerHandler implements ActionListener{
public void actionPerformed(ActionEvent e){
generateColor();
repaint();
}
}
// Set the color the Graphics class will use and fill up your rectangle.
public void paint(Graphics g) {
super.paint(g);
g.setColor(c);
g.fillRect(100,100,130,130);
}
public void generateColor(){
c = new Color((int)(255*Math.random()),
(int)(255*Math.random()),
(int)(255*Math.random()));
}
}Welcome, please private msg me if any questions,
cbarton.a
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