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Android Build a Self-Destructing Message Android App Adding Users Using Parse.com Error Messages with Dialogs

Posted by Marco Jonker
Marco Jonker
2,109 Points

Null Pointer Exception crashing Ribbit.

I'm getting a null pointer exception when trying to assign mUsername.getText().toString() to username.

I know what a null pointer exception is, so please spare me the description, but my question is how can I avoid this null pointer exception? The point of this part is to see if all the fields were entered.

Any suggestions? Below is my code.

public class SignUpActivity extends ActionBarActivity {

protected EditText mUsername;
protected EditText mPassword;
protected EditText mEmail;
protected Button mSignUpButton;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_sign_up);

    mUsername = (EditText)findViewById(R.id.usernameField);
    mPassword = (EditText)findViewById(R.id.passwordField);
    mEmail = (EditText)findViewById(R.id.emailField);
    mSignUpButton = (Button)findViewById(R.id.signupButton);

    mSignUpButton.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            String username = mUsername.getText().toString();
            String password = mPassword.getText().toString();
            String email = mEmail.getText().toString();

            username = username.trim();
            password = password.trim();
            email = email.trim();

            if (username.isEmpty() || password.isEmpty() || email.isEmpty()) {
                AlertDialog.Builder builder = new AlertDialog.Builder(SignUpActivity.this);
                builder.setMessage(R.string.signup_error_message)
                    .setTitle(R.string.signup_error_title)
                    .setPositiveButton(android.R.string.ok, null);
                AlertDialog dialog = builder.create();
                dialog.show();
            } else {
                //create new user
            }

        }
    });
    if (savedInstanceState == null) {
        getSupportFragmentManager().beginTransaction()
                .add(R.id.container, new PlaceholderFragment()).commit();
    }
}

4 Answers

Marco Jonker
Marco Jonker
2,109 Points

Ahh. I figured it out. It was ambiguous naming in my XML. Thanks anyways.

Randall Keels
Randall Keels
1,650 Points
Randall Keels
Randall Keels
1,650 Points

Hi Marco,

I am having a NullPointerException in my Ribbit App also but I am earlier in the app development. I am trying to get the OnClickListener to work with the signupText. I followed Ben's lesson to a T but I don't see why it is giving a null error.

Thanks in advance for your support.

Marco Jonker
Marco Jonker
2,109 Points
Marco Jonker
Marco Jonker
2,109 Points

Hi Randall,

Post the relevant code here and I'll see if I can help you figure it out.

Marco

Randall Keels
Randall Keels
1,650 Points
Randall Keels
Randall Keels
1,650 Points

Hi have already started another thread here: LoginActivity.java ~ OnClickListener > signupText EXPLOSION