I am developing a 2d barcode scanner using zxing library on j2me for nokia mobile paltform using Nokia SDK 1.1 for java.

When I run the ZXing MIDlet in the emulator I am getting this message:ZXing MIDlet running.nothing to display.

But it is not displaying the menu that it supposed to display.

I am new to J2ME,so please help me out.

Menu.java


final class Menu extends List implements CommandListener {

private final ZXingMIDlet zXingMIDlet;
private final Command cancelCommand;
private final Command barcodeCommand;


Menu(ZXingMIDlet parent, String title, String item) {
super(title, IMPLICIT); // Set the title of the form
zXingMIDlet = parent;
// Build the UI components
cancelCommand = new Command("Cancel", Command.CANCEL, 0);
barcodeCommand = new Command(item, Command.ITEM, 0);
addCommand(cancelCommand);
addCommand(barcodeCommand);
setCommandListener(this);
}


public String getSelectedString() {
String result = "";
if (getSelectedIndex() != -1) {
result = getString(getSelectedIndex());
}
return result;
}

public void clear() {
while (size() != 0) {
delete(0);
}
}


public void commandAction(Command command, Displayable displayable) {
if (command == cancelCommand) {
Display.getDisplay(zXingMIDlet).setCurrent(zXingMIDlet.getCanvas());
} else if (command == barcodeCommand || command == SELECT_COMMAND) {
if (getSelectedIndex() != -1) {
zXingMIDlet.itemRequest();
}
}
}

}


ZXingMIDlet.java

public final class ZXingMIDlet extends MIDlet {

private static final int ALERT_TIMEOUT_MS = 5 * 1000;

private Canvas canvas;
private Player player;
private VideoControl videoControl;
private Alert confirmation;
private Alert alert;
private Menu history;
private Vector resultHistory;

Displayable getCanvas() {
return canvas;
}

Player getPlayer() {
return player;
}

VideoControl getVideoControl() {
return videoControl;
}

static MultimediaManager buildMultimediaManager() {
return new AdvancedMultimediaManager();
// Comment line above / uncomment below to make the basic version
// return new DefaultMultimediaManager();
}

protected void startApp() throws MIDletStateChangeException {

try {

Image image = Image.createImage("/res/zxing-icon.png");
Displayable splash = new SplashThread(this, 2000, image);
Display.getDisplay(this).setCurrent(splash);

resultHistory = new Vector(5);
System.out.println("hello--------------");
history = new Menu(this, "Scan History", "Use");
System.out.println("hi--------------");
player = createPlayer();
player.realize();
MultimediaManager multimediaManager = buildMultimediaManager();
multimediaManager.setZoom(player);
multimediaManager.setExposure(player);
multimediaManager.setFlash(player);
videoControl = (VideoControl) player.getControl("VideoControl");
canvas = new VideoCanvas(this);
canvas.setFullScreenMode(true);
videoControl.initDisplayMode(VideoControl.USE_DIRECT_VIDEO, canvas);
videoControl.setDisplayLocation(0, 0);
videoControl.setDisplaySize(canvas.getWidth(), canvas.getHeight());
System.out.println("bye--------------");
} catch (IOException ioe) {
throw new MIDletStateChangeException(ioe.toString());
} catch (MediaException me) {
throw new MIDletStateChangeException(me.toString());
}

// Set up one confirmation and alert object to re-use
confirmation = new Alert(null);
confirmation.setType(AlertType.CONFIRMATION);
confirmation.setTimeout(ALERT_TIMEOUT_MS);
Command yes = new Command("Yes", Command.OK, 1);
confirmation.addCommand(yes);
Command no = new Command("No", Command.CANCEL, 1);
confirmation.addCommand(no);
alert = new Alert(null);
alert.setTimeout(ALERT_TIMEOUT_MS);
}

void splashDone() {
try {
videoControl.setVisible(true);
player.start();
} catch (MediaException me) {
showError(me);
}
Display.getDisplay(this).setCurrent(canvas);
}

private static Player createPlayer() throws IOException, MediaException {

Player player = null;
String platform = System.getProperty("microedition.platform");
if (platform != null && platform.indexOf("Nokia") >= 0) {
try {
player = Manager.createPlayer("capture://image");
} catch (MediaException me) {
// if this fails, just continue with capture://video
} catch (NullPointerException npe) {
} catch (Error e) {

}
}
if (player == null) {
try {
player = Manager.createPlayer("capture://video");
} catch (NullPointerException npe) {

throw new MediaException("Image/video capture not supported on this phone");
}
}
return player;
}

protected void pauseApp() {
if (player != null) {
try {
player.stop();
} catch (MediaException me) {
// continue?
showError(me);
}
}
}

protected void destroyApp(boolean unconditional) {
if (player != null) {
videoControl = null;
try {
player.stop();
} catch (MediaException me) {
// continue
}
player.deallocate();
player.close();
player = null;
}
}

void stop() {
destroyApp(false);
notifyDestroyed();
}

void historyRequest() {
Display.getDisplay(this).setCurrent(history);
}


private void showOpenURL(String title, String display, final String uri) {
confirmation.setTitle(title);
confirmation.setString(display);
CommandListener listener = new CommandListener() {
public void commandAction(Command command, Displayable displayable) {
if (command.getCommandType() == Command.OK) {
try {
platformRequest(uri);
} catch (ConnectionNotFoundException cnfe) {
showError(cnfe);
} finally {
stop();
}
} else {
// cancel
Display.getDisplay(ZXingMIDlet.this).setCurrent(getCanvas());
}
}
};
confirmation.setCommandListener(listener);
showAlert(confirmation);
}

private void showAlert(String title, String text) {
alert.setTitle(title);
alert.setString(text);
alert.setType(AlertType.INFO);
showAlert(alert);
}

void showError(Throwable t) {
String message = t.getMessage();
if (message != null && message.length() > 0) {
showError(message);
} else {
showError(t.toString());
}
}

void showError(String message) {
alert.setTitle("Error");
alert.setString(message);
alert.setType(AlertType.ERROR);
showAlert(alert);
}

private void showAlert(Alert alert) {
Display display = Display.getDisplay(this);
display.setCurrent(alert, canvas);
}

void barcodeAction(ParsedResult result) {
ParsedResultType type = result.getType();
if (type.equals(ParsedResultType.URI)) {
String uri = ((URIParsedResult) result).getURI();
showOpenURL("Open Web Page?", uri, uri);
} else if (type.equals(ParsedResultType.EMAIL_ADDRESS)) {
EmailAddressParsedResult emailResult = (EmailAddressParsedResult) result;
showOpenURL("Compose E-mail?", emailResult.getEmailAddress(), emailResult.getMailtoURI());
} else if (type.equals(ParsedResultType.SMS)) {
SMSParsedResult smsResult = (SMSParsedResult) result;
showOpenURL("Compose SMS?", smsResult.getNumbers()[0], smsResult.getSMSURI());
} else if (type.equals(ParsedResultType.PRODUCT)) {
ProductParsedResult productResult = (ProductParsedResult) result;
String uri = "http://www.google.com/m/products?q=" +
productResult.getNormalizedProductID() + "&source=zxing";
showOpenURL("Look Up Barcode Online?", productResult.getProductID(), uri);
} else if (type.equals(ParsedResultType.TEL)) {
TelParsedResult telResult = (TelParsedResult) result;
showOpenURL("Dial Number?", telResult.getNumber(), telResult.getTelURI());
} else {
showAlert("Barcode Detected", result.getDisplayResult());
}
}

void itemRequest() {
ParsedResult result = (ParsedResult) resultHistory.elementAt(history.getSelectedIndex());
barcodeAction(result);
}

void handleDecodedText(Result theResult) {
ParsedResult result = ResultParser.parseResult(theResult);
String resultString = result.toString();
int i = 0;
while (i < resultHistory.size()) {
if (resultString.equals(resultHistory.elementAt(i).toString())) {
break;
}
i++;
}
if (i == resultHistory.size()) {
resultHistory.addElement(result);
history.append(result.getDisplayResult(), null);
}
barcodeAction(result);
}

}