clickme.java

Java程序设计技巧与开发实例附书源代码。

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

public class ClickMe
    extends Applet
    implements ActionListener { //域申明
  private Button quit = new Button("Quit");
  private Button click = new Button("Click here");
  private TextField text = new TextField(10);
  private boolean secondClick = false;
  // 方法申明
  public void init() {
    setLayout(new FlowLayout());
    add(quit);
    add(click);
    add(text);
    quit.addActionListener(this);
    click.addActionListener(this);
  }

  public void start() {
    text.setText("Applet started");
  }

  public void stop() {
    text.setText("Applet stopped");
  }

  public void actionPerformed(ActionEvent e) {
    if (e.getSource() == quit) {
      text.setText("Can not quit applets");
    }
    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;
    }
  }
}