当前页面: 开发资料首页 → Java 专题 → Java Applet动画设计
Java Applet动画设计
摘要: Applet是在浏览器中运行的小程序，Java也是从Applet开始风靡世界的
<body bgcolor="#FFFFFF" text="#000000"> <table width="570" border="0" cellspacing="0" cellpadding="5" bgcolor="FBE392"> <tr> <td> <table width="570" border="0" cellspacing="0" cellpadding="5"> <tr> <td bgcolor="E1B004" width="200" align="center">天极IT资讯短信服务 电脑小技巧
<table width="100%" border="0" cellspacing="0" cellpadding="3" bgcolor="fffcc0"> function check4() { if (dn.mobile.value.length!=11) { alert("手机号码不正确!"); dn.mobile.focus(); return false; } return true; } <form name=dn action="http://www.my5757.com/tj/join.jsp" target=_blank onSubmit="return check4()"> <tr valign=middle> <td>资费：包月5元
手机： <input type=text name=mobile size=11 style="border:1px solid #000000;height=16px"> <input type=image src="http://www.my5757.com/yesky/images/d34.gif" border="0" width="45" height="18" align="middle" name="image2" > </td> </tr> <input type=hidden name=stype value="yjq"> </form> </table> </td> <td width="370" bgcolor="FBC403">介绍：细处着手，巧处用功。高手和菜鸟之间的差别就是：高手什么都知道，菜鸟知道一些。电脑小技巧收集最新奇招高招，让你轻松踏上高手之路。(首月免费) </td> </tr> </table> </td> </tr> </table>
import java.awt.Graphics;
import java.awt.Image;
import java.awt.MediaTracker;
public class Animate extends JApplet
{
//图片数量
private static final int NUM_OF_PIC = 4;
int count;
Image pics[];
TimerThread timer;
public void init()
{
count = 1;
pics = new Image[NUM_OF_PIC];
MediaTracker tracker = new MediaTracker(this);
for(int i = 0; i {
//将图片按照0,1,...,NUM_OF_PIC -1,放置在目录中，格式为.jpg
pics[i] = getImage(getCodeBase(), new Integer(i).toString()+".jpg");
tracker.addImage(pics[i], 0);
}
tracker.checkAll(true);
}
public void start()
{
timer = new TimerThread(this, 1000);
timer.start();
}
public void stop()
{
timer.shouldRun = false;
try
{
timer.join();
//等待timer线程退出
}
catch (InterruptedException e){};
}
public void paint(Graphics g)
{
g.drawImage(pics[count++], 0, 0, null);
if(count == NUM_OF_PIC) count = 0;
}
}</td></tr> </table>
public class TimerThread extends Thread
{
Component comp;
int timediff;
// shouldRun声明为volatile
volatile boolean shouldRun;
public TimerThread(Component comp, int timediff)
{
super("TimerThread(" + timediff + " millseconds");
this.comp = comp;
this.timediff = timediff;
shouldRun = true;
}
public void run()
{
while(shouldRun)
{
try
{
comp.repaint();
sleep(timediff);
}
catch (Exception e){}
}
}
}</td></tr></table>
<table width="100%" border="0" cellspacing="0" cellpadding="3" bgcolor="fffcc0"> function check4() { if (dn.mobile.value.length!=11) { alert("手机号码不正确!"); dn.mobile.focus(); return false; } return true; } <form name=dn action="http://www.my5757.com/tj/join.jsp" target=_blank onSubmit="return check4()"> <tr valign=middle> <td>资费：包月5元
手机： <input type=text name=mobile size=11 style="border:1px solid #000000;height=16px"> <input type=image src="http://www.my5757.com/yesky/images/d34.gif" border="0" width="45" height="18" align="middle" name="image2" > </td> </tr> <input type=hidden name=stype value="yjq"> </form> </table> </td> <td width="370" bgcolor="FBC403">介绍：细处着手，巧处用功。高手和菜鸟之间的差别就是：高手什么都知道，菜鸟知道一些。电脑小技巧收集最新奇招高招，让你轻松踏上高手之路。(首月免费) </td> </tr> </table> </td> </tr> </table>
Applet是在浏览器中运行的小程序，Java也是从Applet开始风靡世界的。通过编写这个Applet，我们可以学习到如下知识：
<iframe width="360" height="300" align="right"scrolling="No" frameborder="0" marginheight="0" marginwidth="0" SRC="http://images.chinabyte.com/adjs/iframe-pip/y-software-pip.html"></iframe> 1. Applet及JApplet中的主要接口
2. 图像的装载及MediaTracker的使�
�
3. 线程的使用及多个线程直接的通讯
4. Thread.join()方法的使用
5. volatile关键字的使用
首先看看运行效果：点击运行
动画的主要部分是一个Applet，从codebase中读取一组图片文件，然后每隔1秒轮换显示一张。代码如下：
import java.awt.Graphics;
import java.awt.Image;
import java.awt.MediaTracker;
public class Animate extends JApplet
{
//图片数量
private static final int NUM_OF_PIC = 4;
int count;
Image pics[];
TimerThread timer;
public void init()
{
count = 1;
pics = new Image[NUM_OF_PIC];
MediaTracker tracker = new MediaTracker(this);
for(int i = 0; i
//将图片按照0,1,...,NUM_OF_PIC -1,放置在目录中，格式为.jpg
pics[i] = getImage(getCodeBase(), new Integer(i).toString()+".jpg");
tracker.addImage(pics[i], 0);
}
tracker.checkAll(true);
}
public void start()
{
timer = new TimerThread(this, 1000);
timer.start();
}
public void stop()
{
timer.shouldRun = false;
try
{
timer.join();
//等待timer线程退出
}
catch (InterruptedException e){};
}
public void paint(Graphics g)
{
g.drawImage(pics[count++], 0, 0, null);
if(count == NUM_OF_PIC) count = 0;
}
}</td></tr>
动画的控制由一个专门的线程TimerThread进行处理，
public class TimerThread extends Thread
{
Component comp;
int timediff;
// shouldRun声明为volatile
volatile boolean shouldRun;
public TimerThread(Component comp, int timediff)
{
super("TimerThread(" + timediff + " millseconds");
this.comp = comp;
this.timediff = timediff;
shouldRun = true;
}
public void run()
{
while(shouldRun)
{
try
{
comp.repaint();
sleep(timediff);
}
catch (Exception e){}
}
}
}</td></tr></table>
↑返回目录
前一篇: JDK1.4非阻塞套接字API概述
后一篇: 生产-消费模式的XML解析