eventdemo1.java

来自「本java源程序包括了大量的学习程序（共27章）方便大家学习」· Java 代码 · 共 49 行

import java.awt.*;
import java.awt.event.*;
import javax.swing.*; 
public class EventDemo1 extends JFrame
{
   private JButton button;
   private Container container;   //声明内容面板
   
   public EventDemo1() 
   {
	   super("EventDemo");
       setSize(300,200);    //设置窗口大小
       try
       {     //系统外观
 		 	UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
 	   }catch(Exception e){}
 	  
       //获取内容面板
       container = getContentPane();
       
       //创建按钮
       button = new JButton("改变颜色");
       button.setFont(new Font("Serif", Font.PLAIN, 14));
       
       //注册监听器
       button.addActionListener(new ActionListener()
       {
    	  public void actionPerformed(ActionEvent event)   //事件处理方法
    	  {
    		  int red = (int)(Math.random() * 256);
    		  int green = (int)(Math.random() * 256);
    		  int blue = (int)(Math.random() * 256);
    		  container.setBackground(new Color(red, green, blue));
    	  }
       });  
       
       container.add(button, BorderLayout.SOUTH);    //向内容面板中加入按钮组件
      
       setVisible(true);     //设置窗口为可见
       setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }
   
    public static void main(String[] arguments)
    {
       EventDemo1 application = new EventDemo1();     
    }
}