album.java

这是一个小应用程序

import java.awt.*; 
import java.applet.*; 
import java.io.*; 

public class Album extends Applet 
{ 
private Choice C1; 
private String S1[],S2[]; 
private int totalPics; 
private Image offI,img[]; 
private Graphics offG; 
private MediaTracker imagetracker; 
  
public void init() 
{ 
this.setLayout(null); 
C1 = new Choice(); 
C1.setBounds(10,10,290,20); 
totalPics = Integer.parseInt(getParameter("TotalPic")); 
System.out.println(totalPics); 
S1 = new String[totalPics]; 
S2 = new String[totalPics]; 
img = new Image[totalPics]; 
for(int i=0; i<totalPics; i++) 
{ 
S1[i] = new String(""); 
S2[i] = new String(""); 
} 
String s = new String(""); 
imagetracker = new MediaTracker(this); 
for(int i=0; i<totalPics; i++) 
{ 
s = getParameter("Text" + (i+1));   
S1[i] = s; 
System.out.println(S1[i]); 
C1.addItem(s); 
s = getParameter("Picture" + (i+1));   
S2[i] = s; 
img[i] = getImage(getDocumentBase(), s); 
imagetracker.addImage(img[i],0); 
System.out.println(S2[i]); 
} 
try 
{ 
imagetracker.waitForID(0); 
} 
catch(InterruptedException e) 
{ 

} 
add(C1); 
offI = createImage(size().width,size().height-40); 
offG = offI.getGraphics(); 
} 
  
public void paint(Graphics g) 
{ 
g.drawImage(offI,10,40,this); 
} 

public boolean action(Event e , Object o) 
{ 
if(e.target == C1) 
{ 
String s = new String(""); 
offG.setColor(this.getBackground()); 
offG.fillRect(0,40,size().width,size().height-40); 
offI = img[C1.getSelectedIndex()]; 
offG.drawImage(offI,0,0,this); 
repaint(); 
} 
return true; 
} 
}