menucontrol.java

java的菜单控制代码

/*2005.5
菜单控制
devilyx
*/
import java.awt.*;
import java.awt.event.*;

public class fileclose					//定义主类
{
  public static void main(String args[])
  {
    MyMenuFrame mf = new MyMenuFrame();
    mf.setSize(new Dimension(300,200));	//用setSize()方法指定窗口的初始大小
    mf.setVisible(true);		//使窗口可见
  }
}

class MyMenuFrame extends Frame implements ActionListener,TextListener//	//定义窗口
{
    MenuBar m_MenuBar;
    Menu menuFile,menuEdit,menuHelp;
    MenuItem pi_close,pi_open,pi_exit;
    TextArea ta;
    boolean textMod=false;
    String orgMsg="原始信息";
    Button confirmBtn,denyBtn,q;
    Dialog conDialog;

    MyMenuFrame()					//构造函数
    {
    super("菜单窗口");		//指定窗口标题

    confirmBtn=new Button("yes");
    denyBtn=new Button("no");
    q=new Button("q");
    confirmBtn.addActionListener(this);
    denyBtn.addActionListener(this);
    q.addActionListener(this);
    q.setActionCommand("q");

    Panel p3=new Panel();
    ta=new TextArea(5,15);
    ta.setText(orgMsg);
    ta.addTextListener(this);
    //ta.addFocusListener(this);
    this.add(p3);
    p3.add("Center",q);
    p3.add("South",ta);

    m_MenuBar = new MenuBar();//创建菜单条
    menuFile = new Menu("文件");//创建菜单项，创建菜单子项并指定快捷键
    menuEdit = new Menu("编辑");
    menuHelp = new Menu("帮助");

    pi_open = new MenuItem(" open ");
    pi_open.addActionListener(this);
    pi_open.setActionCommand("open");

    pi_close = new MenuItem(" close ");
    pi_close.addActionListener(this);
    pi_close.setActionCommand("close");

    pi_exit = new MenuItem(" exit ");
    pi_exit.addActionListener(this);
    pi_exit.setActionCommand("exit");


    menuFile.add(pi_open);
    menuFile.add(pi_close);
    menuFile.addSeparator();
    menuFile.add(pi_exit);
    m_MenuBar.add(menuFile);
    m_MenuBar.add(menuEdit);
    m_MenuBar.add(menuHelp);

    this.setMenuBar(m_MenuBar);
    addWindowListener(new closeWindow());
    }
    public void actionPerformed(ActionEvent e)//响应动作事件
    {
      if(e.getSource()==confirmBtn)
      {
        ta.setText(ta.getText());
        textMod=false;
        conDialog.dispose();
      }
      else if(e.getSource()==denyBtn)
      {
        ta.setText(orgMsg);
        textMod=false;
        conDialog.dispose();
      }

      else if(e.getActionCommand()=="exit")//选择"退出"菜单则关闭窗口退出程序
      {
        dispose();
        System.exit(0);
      }
      else if(e.getActionCommand()=="q" )
      {
        if(textMod)
        {
            conDialog=new Dialog(this,"确认修改",true);
            Panel p1=new Panel();
            p1.add(new Label("确定修改文本内容?"));
            conDialog.add("Center",p1);
            Panel p2=new Panel();
            p2.add(confirmBtn);
            p2.add(denyBtn);
            conDialog.add("South",p2);
            conDialog.setSize(200,100);
            conDialog.show();
        }
      }
    }

    public void textValueChanged(TextEvent e)//响应CheckboxMenuItem单击事件
    {
        textMod=true;
    }

    class closeWindow extends WindowAdapter
    {
        public void windowClosing(WindowEvent e)
        {
            Frame frm=(Frame)e.getWindow();
            frm.dispose();
            System.exit(0);
        }
    }

}