如何pack applet?

Question

偶有一个applet，有不少Button和Label。
编译运行后，显示有点问题。以前用Frame的话，只要pack一下就行了
但applet不能pack，怎么办？

Answer 1

代码如下:
import java.awt.*;
import java.applet.*;
import java.util.*;
public class DemoApplet extends Applet implements Observer
 {Panel createMyTable()
   {Panel p=new Panel(); int i; //p.setBackground(Color.blue);
    GridBagLayout gbl=new GridBagLayout(); p.setLayout(gbl);
    GridBagConstraints c=new GridBagConstraints();
    Label l=new Label("My Table",Label.CENTER);
    c.gridwidth=GridBagConstraints.REMAINDER;
    gbl.setConstraints(l,c); p.add(l);
    Button bt[]=new Button[6];
    String s[]={"Create Table","Vacant Seat","Vacant Seat","Vacant Seat","Vacant Seat","Vacant Seat"};
    for(i=0;i<s.length;i++)
     {bt[i]=new Button(s[i]);
      c.gridwidth=1; c.gridx=i; c.gridy=1;
      gbl.setConstraints(bt[i],c); p.add(bt[i]);
     }
    CheckboxGroup cbg=new CheckboxGroup(); Checkbox cb[]=new Checkbox[3];
    cb[0]=new Checkbox("One Set",cbg,false);
    cb[1]=new Checkbox("Two Set",cbg,true);
    cb[2]=new Checkbox("Three Set",cbg,false);
    for(i=0;i<cb.length;i++)
     {c.gridwidth=1; c.gridx=i; c.gridy=2;
      gbl.setConstraints(cb[i],c); p.add(cb[i]);
     }
    cbg=new CheckboxGroup(); cb=new Checkbox[3];
    cb[0]=new Checkbox("30 Timeout",cbg,false);
    cb[1]=new Checkbox("40 Timeout",cbg,true);
    cb[2]=new Checkbox("50 Timeout",cbg,false);
    for(i=0;i<cb.length;i++)
     {c.gridwidth=1; c.gridx=i+3; c.gridy=2;
      gbl.setConstraints(cb[i],c); p.add(cb[i]);
     } 
    return p;
   }
  public void init()
   {    
    GridBagLayout gbl=new GridBagLayout(); setLayout(gbl);
    GridBagConstraints c=new GridBagConstraints();
    Label l=new Label("Your Number:",Label.CENTER);
    c.gridwidth=GridBagConstraints.REMAINDER;
    gbl.setConstraints(l,c); add(l);
    Panel p1=createMyTable();
    gbl.setConstraints(p1,c); add(p1); invalidate();//doLayout();//pack();
    resize(640,480);
//    add(new Button("创建牌桌"));   }  public void paint(Graphics g)
   {
/*
        for (int x=0; x<numPoints; ++x)
        {
            g.drawLine(oldX, oldY, points[x].x, points[x].y);
            oldX = points[x].x;
            oldY = points[x].y;
        }*/
    }
   public void update(Observable t, Object o)
    {
    }
   public static void main(String args[]) {
     Frame f = new Frame("GridBag Layout Example");
     DemoApplet ex1 = new DemoApplet();
     ex1.init();
     f.add("Center", ex1);
     f.pack();
     f.setSize(f.getPreferredSize());
     f.show();
     }
  
  }