J2me simple game application

Question

when i select the new Game option Game Screen doesn't work properly.please help me ican't find problem in this program but the project build sucsessfully;
Midlet class....
//@Author Lasantha PW
//Title Java Developer
//Project Name Simple Midlet Game Application
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
//main midlet
public class Mario extends MIDlet{
Display display; //display object
     //private String player,background;
     private Image splashLogo;//splash image
     MainMenuScreen mainMenuScreen;//main menu object
     AboutScreen about;
     boolean isSplash=true; //splash condition
     MarioCanvas marioCanvas;//=new MarioCanvas(this);
     public int noOfLives=3; //player lives
     public Mario(){
          marioCanvas=new MarioCanvas(this);
          about=new AboutScreen(this);
     public void startApp(){
          display=Display.getDisplay(this);
          mainMenuScreen=new MainMenuScreen(this);
          if(isSplash) {
          isSplash=false;
               try {
               splashLogo=Image.createImage("/splash.png");
               new SplashScreen(display,mainMenuScreen,3000,splashLogo);
          catch(Exception ex){}
     public void pauseApp(){
     public void destroyApp(boolean unconditional){
          notifyDestroyed();
     public void mainMenuScreenQuit(){
          destroyApp(true);
     public void mainMenuScreenShow(){
          display.setCurrent(mainMenuScreen);
     public void gameScreenShow(){
          display.setCurrent(marioCanvas);
          marioCanvas.start1();
     public void aboutScreenShow(){
          display.setCurrent(about);
     public void gameScreenQuit(){
          destroyApp(true);
     public Display getDisplay(){
          return display;
Main Menu class..................................
//@Author Lasantha PW
//Title Java Developer
//Project Name Simple Midlet Game Application
import javax.microedition.lcdui.*;
import java.io.IOException;
public class MainMenuScreen extends List implements CommandListener{
     //create midlet object
     private Mario midlet;
     //create command objects
     private Command exit=new Command("Exit",Command.EXIT,1);
     private Command select=new Command("Select",Command.ITEM,1);
     //private MarioCanvas marioCanvas;
     public MainMenuScreen(Mario midlet){
     super("Tank32",Choice.IMPLICIT);
     this.midlet=midlet;
     append("New Game",null);
     append("Settings",null);
     append("High Score",null);
     append("Help",null);
     append("About",null);
     addCommand(exit);
     addCommand(select);
     setCommandListener(this);
     public void commandAction(Command c,Displayable d){
     if(c==exit){
     midlet.mainMenuScreenQuit();return;
     else if(c==select){
     processMenu();return;
     else{
     processMenu();return;
     private void processMenu(){
     List down=(List)midlet.display.getCurrent();
     switch(down.getSelectedIndex()){
     case 0:scnNewGame();break;
     case 1:scnSettings();break;
     case 2:scnHighScore();break;
     case 3:scnHelp();break;
     case 4:scnAbout();break;
     //private methods for processMenu method
     private void scnNewGame(){     
          midlet.gameScreenShow();     
     private void scnSettings(){}
     private void scnHighScore(){}
     private void scnHelp(){}
     private void scnAbout(){
          midlet.aboutScreenShow();
GameScreen......................................
//@Author Lasantha PW
//Title Java Developer
//Project Name Simple Midlet Game Application
import javax.microedition.lcdui.*;
import javax.microedition.lcdui.game.*;
import java.util.*;
public class MarioCanvas extends GameCanvas implements Runnable,CommandListener{
//command objects
     private Command exit=new Command("Exit",Command.EXIT,1);
     //main midlet
     public Mario midlet;
     public boolean isPlay=true;
     public int dx=4;
     public int dy=4;
     public int BASE=(2*getHeight())/3;
     public Vector allObstacles;
     //Resourse for player
     public Image playerPic;
     Player player;
     public boolean leftTrueRightFalse=true;
     //Power power;
     Image powerPic;
     //resourse for devils
     public Image devilPic;
     Devil devil1;
     LayerManager layerManager;
     public MarioCanvas(Mario midlet){
          super(true);
          this.midlet=midlet;
          addCommand(exit);
          setCommandListener(this);
     public void start1(){
          try{
               //initialize all image objets
               playerPic=Image.createImage("/player.png");
               //powerPic=Image.createImage("/power.png");
               devilPic =Image.createImage("/Devil.png");
               //player object
               Player player=new Player(playerPic,0,BASE-15,this);
               //obstacle objects
               devil1=new Devil(devilPic,player,100,BASE-15);
               //vector object
               allObstacles=new Vector(0,100);
               //bullets=new Vector();
               //add obstacles to the vector
               allObstacles.addElement(((Sprite)devil1));
               //set all obstacles to player
               player.setAllObstacles(allObstacles);          
               layerManager=new LayerManager();
               //append to the layermanager     
               layerManager.append(player);
               layerManager.append(devil1);
               Thread t=new Thread(this);
               t.start();
          catch(Exception ex){
               System.err.println("Error"+ex);
     public void run(){
          while(isPlay){
               userInput();
               verifyGameState();
               updateBackground();
               updateGameScreen();
          try{Thread.currentThread().sleep(15);}
          catch(Exception ex){}                    
     public void updateBackground(){
          Graphics g=getGraphics();
          g.setColor(0,124,0);
          g.fillRect(0,0,this.getWidth(),this.getHeight());
          g.setColor(0,224,0);
          g.fillRect(0,BASE+30,this.getWidth(),80);
     public void updateGameScreen(){
          Graphics g=this.getGraphics();
          if(player.Y<BASE){
          //player.incrementY(dy);
          else if(player.Y>BASE){
          player.Y=BASE;
          player.setY(BASE);}
          g.setColor(0,244,0);
          g.fillRect(0,BASE+30,1500,80);
          layerManager.paint(g,0,0);
          flushGraphics();
     public void userInput(){
          if((this.getKeyStates()&LEFT_PRESSED)!=0){}
          if((this.getKeyStates()&RIGHT_PRESSED)!=0){}
          if((this.getKeyStates()&FIRE_PRESSED)!=0){}     
     public void verifyGameState(){
     public void commandAction(Command c,Displayable d){
          if(c==exit){
               midlet.gameScreenQuit();
}

Answer 1

pwlasantha wrote:
when i select the new Game option Game Screen doesn't work properly.please help me ican't find problem in this program but the project build sucsessfully;
...If it "doesn't work properly", there's "something going wrong".