eventhandleframe(1).java

递归子程序法：对应每个非终结符语法单元编一个独立的处理过程（或子程序）。语法分析从读入第一个单词开始

package eventhandle;
	/** 
	 * Java语言实验参考程序
	 * Company 北京师范大学计算机系
 
	 * @author 孙一林
	 * @version 1.0
	 */
import java.awt.*;
import java.awt.event.*;
public class EventHandleFrame extends Frame {
  MenuBar menuBar = new MenuBar();
  Menu menu1 = new Menu();
  MenuItem menuItem1 = new MenuItem();
  Menu menu2 = new Menu();
  MenuItem menuItem2 = new MenuItem();
  public EventHandleFrame() {
    try {
      Init();
    }
    catch(Exception e) {
      e.printStackTrace();
    }
  }
  public static void main(String[] args) {
    EventHandleFrame eventHandleFrame = new EventHandleFrame();
    eventHandleFrame.setSize(400,300);
    eventHandleFrame.show();
  }
  private void Init() throws Exception {
    this.setTitle("菜单事件响应");
    this.setMenuBar(menuBar);
    menu1.setLabel("File");
    menuItem1.setLabel("Exit");
    menu2.setLabel("Help");
    menuItem2.setLabel("About");
    menuBar.add(menu1);
    menuBar.add(menu2);
    menu1.add(menuItem1);
    menu2.add(menuItem2);
    /* ============== 开始添加菜单事件监听器和适配器类代码 ============== */
    menuItem1.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        menuItem1_actionPerformed(e);
      }
    });
    menuItem2.addActionListener(new java.awt.event.ActionListener() {
      public void actionPerformed(ActionEvent e) {
        menuItem2_actionPerformed(e);
      }
    });
    /* ============== 添加菜单事件监听器和适配器类代码结束 ============== */
  }
  /* ================= 开始添加菜单事件处理方法代码 =================== */
  void menuItem1_actionPerformed(ActionEvent e) {
    dispose();
    System.exit(1);
  }
  void menuItem2_actionPerformed(ActionEvent e) {
    AboutDialog aboutDialog = new AboutDialog(this, "About", true);
    aboutDialog.setSize(400,300);
    aboutDialog.show();
  }
  /* ================= 添加加菜单事件处理方法代码结束 ================== */
}
/* ======================= About对话框类 ========================= */
class AboutDialog extends Dialog {
  Panel panel1 = new Panel();
  Label label = new Label();
  Button button = new Button();
  public AboutDialog(Frame frame, String title, boolean modal) {
    super(frame, title, modal);
    enableEvents(AWTEvent.WINDOW_EVENT_MASK);
    try {
      Init();
      add(panel1);
      pack();
    }
    catch(Exception ex) {
      ex.printStackTrace();
    }
  }

  public AboutDialog(Frame frame) {
    this(frame, "", false);
  }

  public AboutDialog(Frame frame, boolean modal) {
    this(frame, "", modal);
  }
  public AboutDialog(Frame frame, String title) {
    this(frame, title, false);
  }
  void Init() throws Exception {
    label.setText("Copyright(c) 2003");
    label.setBounds(new Rectangle(108, 92, 164, 46));
    panel1.setLayout(null);
    button.setLabel("OK");
    button.setBounds(new Rectangle(137, 198, 84, 31));
    panel1.add(button, null);
    panel1.add(label, null);
  }
  protected void processWindowEvent(WindowEvent e) {
    if (e.getID() == WindowEvent.WINDOW_CLOSING) {
      cancel();
    }
    super.processWindowEvent(e);
  }
  void cancel() {
    dispose();
  }
}