使用GridBagLayout布局

GridBagLayout布局可以随窗口大小调整位置。
import java.awt.*;
import java.applet.Applet;

public class GridBagEx1 extends Applet {

     protected void makebutton(String name,
                               GridBagLayout gridbag,
                               GridBagConstraints c) {
         Button button = new Button(name);
         gridbag.setConstraints(button, c);
         add(button);
     }

     public void init() {
         GridBagLayout gridbag = new GridBagLayout();
         GridBagConstraints c = new GridBagConstraints();
         setFont(new Font("SansSerif", Font.PLAIN, 14));
         setLayout(gridbag);

         c.fill = GridBagConstraints.BOTH;
         c.weightx = 1.0;
         makebutton("Button1", gridbag, c);
         makebutton("Button2", gridbag, c);
         makebutton("Button3", gridbag, c);

         c.gridwidth = GridBagConstraints.REMAINDER; //end row
         makebutton("Button4", gridbag, c);

         c.weightx = 0.0;                  //reset to the default
         makebutton("Button5", gridbag, c); //another row

           c.gridwidth = GridBagConstraints.RELATIVE; //next-to-last in row
         makebutton("Button6", gridbag, c);

           c.gridwidth = GridBagConstraints.REMAINDER; //end row
         makebutton("Button7", gridbag, c);

         c.gridwidth = 1;                //reset to the default
         c.gridheight = 2;
         c.weighty = 1.0;
         makebutton("Button8", gridbag, c);

         c.weighty = 0.0;                  //reset to the default
           c.gridwidth = GridBagConstraints.REMAINDER; //end row
           c.gridheight = 1;               //reset to the default
         makebutton("Button9", gridbag, c);
         makebutton("Button10", gridbag, c);
         makebutton("Button11", gridbag, c);
         makebutton("Button12", gridbag, c);

         setSize(400, 200);
     }

     public static void main(String args[]) {
           Frame f = new Frame("GridBag Layout Example");
          
           GridBagEx1 ex1 = new GridBagEx1();
           ex1.init();
           f.add("Center", ex1);
           f.pack();
           f.setSize(f.getPreferredSize());
           f.show();
     }
}