import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class Navigator extends MIDlet implements CommandListener {

Command exit=new Command("Выход", Command.EXIT, 0);
Command gotb=new Command("TextBoks",Command.SCREEN, 1);
Command goform=new Command("Form", Command.SCREEN, 2);
Command golist=new Command("List", Command.SCREEN, 3);
Command goalert=new Command("Alert", Command.SCREEN, 4);

int go=0;

  TextBoks tb=new TextBoks("text",156,0);
  Form f=new Form("Label");
  List l=new List("text zagolovok",List.IMPLICIT);
  Alert a=new Alert("Zagolovok","Please, wait...",null,null);

   public Navigator(){
Display d=Display.getDisplay(this);
   }

public void startApp(){
    go++;
 tb.addCommand(exit);
 tb.addCommand(goform);
 tb.addCommand(golist);
 tb.addCommand(goalert);
    tb.setCommandListener(this);
    d.setCurrent(tb);
 }

public void pauseApp(){
 }

 public void destroyApp(boolean unco){
    notifyDestroyed();
 }

 public void commandAction(Command c, Displayable d){

  if(c==exit){
destroyApp(false);
notifyDestroyed();}

  if(c==goform){
    go++;
 f.addCommand(exit);
 f.addCommand(golist);
 f.addCommand(gotb);
 f.addCommand(goalert);
    f.setCommandListener(this);
    Display.getDisplay(this).setCurrent(f);}

    if(c==golist){
 l.addCommand(exit);
 l.addCommand(goalert);
 l.addCommand(gotb);
 l.addCommand(goform);
    l.setCommandListener(this);
    Display.getDisplay(this).setCurrent(l);}

  if(c==goalert){
   go++;
 a.addCommand(exit);
 a.addCommand(golist);
 a.addCommand(goform);
 a.addCommand(gotb);}
    f.setCommandListener(this);
    Display.getDisplay(this).setCurrent(f);}

  if(c==gotb){
 go++;
startApp();}
 }
}