buttonevent.java

Java 图形界面入门实例

import java.awt.*;
import java.applet.Applet;
import java.awt.event.*;
public class buttonEvent extends Applet
{
   Button button;
   public void init()
   {
      resize(500,200);
      button=new Button("Add one line");
      add(button);
    }
    
    public boolean action(Event e,Object arg)
    {
       if(e.target==button)
       {  int x1=(int)(Math.random()*500);
          int y1=(int)(Math.random()*200);
          int x2=(int)(Math.random()*500);
          int y2=(int)(Math.random()*200);
          getGraphics().drawLine(x1,y1,x2,y2);
           return true;
       }
       else
          return false;
     }
}