1） 在网页上用Applet实现画图的功能。
HTML内调用程序：
<applet code=MyApplet width=300 heigth=300 bgColor=red></applet>
画图程序：
import java.awt.*;
import java.applet.*;
import java.awt.event.*;
public class MyApplet extends Applet
{
int orgX;
int orgY;
int endX;
int endY;
public void paint(Graphics g)
{
g.drawString("this is a simple applet",50,50);
}
public void init()
{
addMouseListener(new MouseAdapter()
{
public void mousePressed(MouseEvent e)
{
orgX=e.getX();//获得初始点的横坐标
orgY=e.getY();//获得初始点的纵坐标
}
public void mouseReleased(MouseEvent e)
{
endX=e.getX();//获得末点横坐标
endY=e.getY();//获得末点纵坐标
getGraphics().drawLine(orgX,orgY,endX,endY);
}
});
}
}
2） 动画小程序
package applet;
import java.applet.*;
import java.awt.*;
public class MyApplet extends Applet implements Runnable{
int index=0;
String teString=null;
Image []imgs=new Image[3];
public void init()
{
for (int i = 0; i < 3; i++) {
imgs[i]=getImage(getCodeBase(),"zhaopin"+(i+1)+".jpg");
}
new Thread(this).start();
}
public void paint(Graphics g)
{
g.drawImage(imgs[index], 20, 20, this);
g.setFont(new Font(null,Font.ITALIC|Font.BOLD,20));
g.drawString(""+index, 10,20);
}
public void run() {
while (true) {
try {
Thread.sleep(100);
} catch (InterruptedException e) {
e.printStackTrace();
}
index=(index+1)%3;
repaint();
}
}
}
问题：图片未显示
3） 通过网页传递给applet信息
在网页上设置变量：<param name=interval value=100>
在Applet上获得变量： time1=Integer.parseInt(getParameter("interval"));
4） 网页上用户和Applet的交互
网页：
<html>
<head>
<title>MyHtml.html</title>
</head>
<body bgColor="000000">
<center>
<applet
code="MyApplet1.class"
name="app"
width=500
height=300
>
<param name=interval value=100>
</applet>
</center>
<script language="javascript">
function setTest()
{
document.app.text=content.value;
document.app.repaint();
}
</script>
<input type=text name=content>
<input type=button value="改变文本"
οnclick="setTest()">
</body>
</html>
Applet程序:
import java.applet.*;
import java.awt.*;
public class MyApplet1 extends Applet implements Runnable{
public String text="";
int index=0;
int time1=100;
Image []imgs=new Image[10];
public void init()
{
for (int i = 0; i < 10; i++) {
imgs[i]=getImage(getCodeBase(),"images//zhaopin"+(i+1)+".bmp");
}
time1=Integer.parseInt(getParameter("interval"));
//new Thread(this).start();
}
public void paint(Graphics g)
{
g.drawImage(imgs[index],20,20,this);
g.setFont(new Font(null,Font.ITALIC|Font.BOLD,30));
g.drawString(text, 50, 60);
}
public void run() {
while (true) {
try {
Thread.sleep(time1);
} catch (InterruptedException e) {
e.printStackTrace();
}
index=(index+1)%10;
repaint();
}
}
}
