Creating Midlet Application For Login in J2ME

[AbdullahDar]

The above code gives no errors and the emulator starts running, but the Login Screen is not being displayed on the emulator.
I am working in j2me sdk 3.0.
Anyone please tell me why it isnt showing the Login Screen.

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

public class LoginExample extends MIDlet implements CommandListener{
  private Display display;
  private TextField userName,password;
  public Form form;
  private Command login,cancel;
  private Image img, imge, img2;
      
  public LoginExample() {
    form = new Form("Sign in");
    userName = new TextField("LoginID:", "", 30, TextField.ANY);
    password = new TextField("Password:", "", 30, TextField.PASSWORD);
    cancel = new Command("Cancel", Command.CANCEL, 2);
    login = new Command("Login", Command.OK, 2);
    try{
      img = Image.createImage("/logo.png");
      imge = Image.createImage("/front_left1_bad.png");
      img2 = Image.createImage("/Congratulations-1.png");
    }catch(Exception e){
      System.out.println(e.getMessage());
    }    
  }

   public void startApp() {
    display = Display.getDisplay(this);
    try{form.append(img);}catch(Exception e){}
    form.append(userName);
    form.append(password);
    form.addCommand(cancel);
    form.addCommand(login);
    form.setCommandListener(this);
    display.setCurrent(form);
  }

  public void pauseApp() {}

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

  public void validateUser(String name, String password) {
    if (name.equals("sandeep") && password.equals("sandeep")) {
      showMsg();
    } else {
      tryAgain();
    }
  }  

  public void showMsg() {
    Alert success = new Alert("Login Successfully", 
    "Your Login Process is completed!", 
     img2, AlertType.INFO);
    success.setImage(img2);
    userName.setString("");
    password.setString("");
    display.setCurrent(success, form);    
  }

  public void tryAgain() {
    Alert error = new Alert("Login Incorrect", "Please 
    try again", imge, AlertType.ERROR);
    error.setTimeout(900);
    error.setImage(imge);
    userName.setString("");
    password.setString("");
    display.setCurrent(error, form);
  }
  
  public void commandAction(Command c, Displayable d) {
    String label = c.getLabel();
    if(label.equals("Cancel")) {
      destroyApp(true);
    } else if(label.equals("Login")) {
      validateUser(userName.getString(), password.getString());
    } 
  }
}

[BestJewSinceJC]

Code snippets should be posted for working code, post a regular thread for questions in the future.

[ll-bigboy-ll]

try dis hope it helps u

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

public class LoginExample  extends MIDlet implements CommandListener{
private Display Display;
private TextField userName,password;
public Form form;
private Command login,cancel;
private Image img, imge, img2;

public LoginExample () {
form = new Form("Sign in");
userName = new TextField("LoginID:", "", 30, TextField.ANY);
password = new TextField("Password:", "", 30, TextField.PASSWORD);
cancel = new Command("Cancel", Command.CANCEL, 2);
login = new Command("Login", Command.OK, 2);
try{
img = Image.createImage("/1.png");
imge = Image.createImage("/2.png");
img2 = Image.createImage("/3.png");
}catch(Exception e){
System.out.println(e.getMessage());
}
}

public void startApp() {
Display = Display.getDisplay(this);
try{form.append(img);}catch(Exception e){}
form.append(userName);
form.append(password);
form.addCommand(cancel);
form.addCommand(login);
form.setCommandListener(this);
Display.setCurrent(form);
}

public void pauseApp() {}

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

public void validateUser(String name, String password) {
if (name.equals("max99") && password.equals("1234")) {
showMsg();
} else {
tryAgain();
}
}


public void showMsg() {
Alert success = new Alert("Login Successfully", "Your Login Process is completed!", img2, AlertType.INFO);
success.setImage(img2);
userName.setString("");
password.setString("");
Display.setCurrent(success, form);
}

public void tryAgain() {
Alert error = new Alert("Login Incorrect", "Please try again", imge, AlertType.ERROR);
error.setTimeout(900);
error.setImage(imge);
userName.setString("");
password.setString("");
Display.setCurrent(error, form);
}


public void commandAction(Command e, Displayable d) {
String label = e.getLabel();
if(label.equals("Cancel")) {
destroyApp(true);
} else if(label.equals("Login")) {
validateUser(userName.getString(), password.getString());
}
}
}

[safz17]

why doesnt the progrm wrk crrctly of i exclude the img cmds..my code is as follows:

import javax.microedition.midlet.MIDlet;
import javax.microedition.lcdui.*;
public class LoginExamples extends MIDlet implements CommandListener{
  private Display display;
  private TextField userName,password;
  public Form form;
  private Command login,cancel;
 
  public LoginExamples() {
  form = new Form("Sign in");
  userName = new TextField("LoginID:", "", 30, TextField.ANY);
  password = new TextField("Password:", "", 30, TextField.PASSWORD);
  cancel = new Command("Cancel", Command.CANCEL, 2);
  login = new Command("Login", Command.OK, 2);
  }
 
  public void startApp() 
  {
  display = Display.getDisplay(this);
  form.append(userName);
  form.append(password);
  form.addCommand(cancel);
  form.addCommand(login);
  form.setCommandListener(this);
  display.setCurrent(form);
  }

  public void pauseApp() {}
  public void destroyApp(boolean unconditional) 
  {
  notifyDestroyed();
  }
  
  public void validateUser(String name, String password) {
  if (name.equals("sandeep") && password.equals("sandeep")) 
  {
  showMsg();
  } else {
  tryAgain();
  }
  }  
  public void showMsg() {

  Alert success = new Alert("Login Successfully Your Login Process is completed!",AlertType.INFO);
  userName.setString("");
  password.setString("");
  display.setCurrent(success, form);  
  }

  public void tryAgain() {
  Alert error = new Alert("Login Incorrect Please try again",AlertType.ERROR);
  error.setTimeout(900);
  userName.setString("");
  password.setString("");
  display.setCurrent(error, form);
  }
  public void commandAction(Command c, Displayable d) {
  String label = c.getLabel();
  if(label.equals("Cancel")) {
  destroyApp(true);
  } else if(label.equals("Login")) {
  validateUser(userName.getString(), password.getString());
  } 
  }
}

but this doesnt seem to work..is it necessary to include the image cmds?

[_neo_]

In first and second codes class name were LoginExample.
In last snippet it is LoginExamples. Have you changed your project properties for LoginExample"S" ???