clickme.java

Java程序设计技巧与开发实例附书源代码。

import java.awt.*;
import java.awt.event.*;
public class ClickMe extends Frame implements ActionListener
{  // 定义域
   private Button quit = new Button("Quit");
   private Button click = new Button("Click here");
   private TextField text = new TextField(10);
   private boolean secondClick = false;
   //定义构造方法
   public ClickMe()
   {  super("Click Example");
      setLayout(new FlowLayout());
      add(quit);  add(click);
      click.addActionListener(this);
      quit.addActionListener(this);
      add(text);
      pack();  show();
   }
   // 定义方法
   public void actionPerformed(ActionEvent e)
   {  if (e.getSource() == quit)
         System.exit(0);
      else if (e.getSource() == click)
      {  if (secondClick)
            text.setText("第一次点击！");
         else
            text.setText("第二次点击哦！");
         secondClick = !secondClick;
      }
   }
//标准main方法
  public static void main(String args[])
   {  ClickMe myFrame = new ClickMe(); }
}