[J2ME] 基本框架框架

 

 1 import javax.microedition.lcdui.Command;

 2 import javax.microedition.lcdui.CommandListener;

 3 import javax.microedition.lcdui.Display;

 4 import javax.microedition.lcdui.Displayable;

 5 import javax.microedition.lcdui.TextBox;

 6 import javax.microedition.midlet.MIDlet;

 7 import javax.microedition.midlet.MIDletStateChangeException;

 8 

 9 

10 public class main extends MIDlet implements CommandListener {

11 

12     private Command exitCom;

13     private Display ds;

14     private TextBox tb;

15     

16     //构造函数

17     public main() {

18         // TODO Auto-generated constructor stub

19         ds=Display.getDisplay(this);//创建Display类一个实体

20         exitCom=new Command("Exit",Command.EXIT,1);//创建Command对象一个实体，并设置Exit命令用于退出这个MIDlet

21         tb=new TextBox("Hellow MIDlet","Hellow World",15,0);//创建用来输出东西的TextBox对象

22         tb.addCommand(exitCom);//使Command对象和TextBox关联起来

23         tb.setCommandListener(this);//当TextBox显示在屏幕上时，使CommandListener响应发生的事件

24     }

25 

26     protected void destroyApp(boolean arg0) throws MIDletStateChangeException {

27         // TODO Auto-generated method stub

28         

29     }

30 

31     //当系统要求MIDlet暂停时调用

32     protected void pauseApp() {

33         // TODO Auto-generated method stub

34 

35     }

36 

37     //第一次启动或者暂停后重启时由系统调用startApp()方法

38     protected void startApp() throws MIDletStateChangeException {

39         // TODO Auto-generated method stub

40         ds.setCurrent(tb);//将构造函数中的TextBox设置为当前的屏幕

41     }

42 

43     //用户触发任何Command是，做出回应，系统会自动调用这个方法

44     public void commandAction(Command arg0, Displayable arg1) {

45         // TODO Auto-generated method stub

46         if(arg0==exitCom){

47             try {

48                 destroyApp(false);

49                 notifyDestroyed();

50             } catch (MIDletStateChangeException e) {

51                 // TODO Auto-generated catch block

52                 e.printStackTrace();

53             }

54         }

55     }

56 

57 }