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<title>csdn_小议如何在Applet中显示图象</title>
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        <td WIDTH="50%" bordercolor="#FFFFFF" CLASS="t1" bgcolor="#F0F0F0" align="center" nowrap>小议如何在Applet中显示图象  </td>
    <p>    <td WIDTH="50%" bordercolor="#FFFFFF" CLASS="t1" bgcolor="#F0F0F0" align="center" nowrap>作者：jeru</td></p>
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      <tr>        <td WIDTH="100%" bordercolor="#FFFFFF" CLASS="t" bgcolor="#F0F0F0" colspan="2">
        <b>一.在 Applet 中显示图象需要引入以下包,并调用ImageObserver接口</b>
</p><p>import java.awt.image.*; 
</p><p>import java.awt.image.ImageObserver; 
</p><p>import java.net.URL; 
</p><p>
</p><p>public class MyApplet extends Applet implements ImageObserver { ...
</p><p>
</p><p><b>二.定义图象路径</b>
</p><p>URL imgURL = getDocumentBase()；
</p><p>将路径设为和你的html文件在相同。
</p><p>URL imgUrl = getClassBase()；
</p><p>将路径设为和你的html文件在相同。
</p><p>
</p><p><b>三.获取图象</b>
</p><p>img = getImage(imgURL,imgName); 
</p><p>当然，有可能你想将自己的图象文件放到一个目录里去，那么你可以这样做
</p><p>img = getImage(imgURL, "img" + imgName);
</p><p>
</p><p><b>四.显示图象</b>
</p><p>最基本方法是调用 drawImage(),这个方法在Graphics类中有定义,最简单的调用形式如下：
</p><p>g.drawImage(image, xPosition, yPosition, this);
</p><p>最后一个参数呼叫了ImageObserver. 
</p>
        <p><b>五.最后的补充</b>
</p><p>以上所说的都是最基本的，当然有时候你甚至想把你的图象文件打成jar包，这时，你就需要用到
</p><p>getResourceAsStream() 方法了。
</p><p>InputStream in = getClass().getResourceAsStream("image.gif");
</p><p>byte buffer[] = new byte[in.available()];
</p><p>for (int i = 0; n = in.available(); i < n; i ++)
</p><p>  buffer[i] = (byte)in.read();
</p><p>Image img = createImage(buffer);
</p><p>
</p><p><b>六.一个完整的小实例</b>
</p><p>
</p><p>import java.awt.*; 
</p><p>import java.applet.*; 
</p><p>import java.awt.image.*; 
</p><p>import java.awt.image.ImageObserver; 
</p><p>import java.net.URL; 
</p><p>
</p><p>//使用ImageObserver接口
</p><p>public class MyApplet extends Applet implements ImageObserver{
</p><p>  Image img;   
</p><p>  String imgPath = "";
</p><p>  int xpoint = 100, ypoint = 100;
</p><p>      
</p><p>  public void init() {        
</p><p>    setBackground(Color.white); //设置背景色
</p><p>    setForeground(Color.blue); //设置前景色
</p><p>    imgPath = "img/" + "test.gif"; //设置图象文件路径 
</p><p>  } 
</p><p>  
</p><p>  public void paint(Graphics g) {
</p><p>    URL imgURL = getDocumentBase(); 
</p><p>    img = getImage(imgURL, imgPath);     
</p>
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