myexample.java

编写Applet

import java.awt.*;
import java.awt.event.*;

public class Myexample extends WindowAdapter
                        implements ActionListener{
   Frame f;
   Panel p;
   Label l;
   
   Button b1,b2;
   int i=20;


   public static void main(String args[]){
        Myexample me=new Myexample();
        me.go();
    }
   public void go()
  {
        f=new Frame("Myexample");
        p=new Panel();
        b1=new Button("放大");
        b2=new Button("缩小");
        l=new Label("Hello");
       
        f.add("Center",p);
        f.add("East",b1);
        f.add("West",b2);
       
        p.add(l);
        
        b1.addActionListener(this);
        b2.addActionListener(this);  
       
        f.addWindowListener(this);
     
       
       
        f.setSize(300,200);
        f.setVisible(true);
  }


public void actionPerformed(ActionEvent e){
  if(e.getActionCommand()=="放大"){
   i++;
   l.setFont(new Font("TimesRoman",Font.PLAIN,i));

  }
  if(e.getActionCommand()=="缩小"){
   i--;
   l.setFont(new Font("TimesRoman",Font.PLAIN,i));

  }
}

public void windowClosing(WindowEvent e)
{
  System.exit(0);
}
 }