import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import java.net.*; public class canvaser extends Applet implements ActionListener { Button button1;
BoxCanvas boxcanvas;
int loop_index;
public void init() {
add(button1=new Button("Move Rectangle"));
button1.addActionListener(this);
boxcanvas=new BoxCanvas();
boxcanvas.resize(150,250);
add(boxcanvas);
} public void actionPerformed(ActionEvent event) {
if(event.getSource()==button1) {
for(loop_index=0; loop_index<250; loop_index++) {
boxcanvas.setLocation(loop_index,50);
} } }
} class BoxCanvas extends java.awt.Canvas {
Image image;
public void init() {
image = getImage(getCodeBase(),"java.gif");
}
public void paint(Graphics g) {
g.drawImage(image,0,0,30,30,this); } }
import java.awt.event.*;
import java.applet.*;
import java.net.*; public class canvaser extends Applet implements ActionListener { Button button1;
BoxCanvas boxcanvas;
int loop_index;
public void init() {
add(button1=new Button("Move Rectangle"));
button1.addActionListener(this);
boxcanvas=new BoxCanvas();
boxcanvas.resize(150,250);
add(boxcanvas);
} public void actionPerformed(ActionEvent event) {
if(event.getSource()==button1) {
for(loop_index=0; loop_index<250; loop_index++) {
boxcanvas.setLocation(loop_index,50);
} } }
} class BoxCanvas extends java.awt.Canvas {
Image image;
public void init() {
image = getImage(getCodeBase(),"java.gif");
}
public void paint(Graphics g) {
g.drawImage(image,0,0,30,30,this); } }
getImage()和getCodeBase()这两个方法都是Applet类中的的方法,
因此当然把class BoxCanvas extends java.awt.Canvas
换成class BoxCanvas extends Applet时运行通过,
但是这可能没是你想要的,它可能会与你的本意相背
再说了一上面的方法去该,那么这段代码也就失去了它原由的意义。