title: Change DisplayName in Firebase
body: <p>I am using email registration Firebase. As of now their is no option to set DisplayName in Firebase. So I am redirecting users to a class where they can change DisplayName soon after signing up through email and password.</p>
  
  <p>My problem is I am unable to achieve that. Here's what I have done so far:</p>
  
  <pre><code>public class UsernameActivity extends AppCompatActivity {
  private FirebaseAuth.AuthStateListener authListener;
  private FirebaseAuth auth;
  private EditText mName;
  private TextView btnSignUp;
  @Override
  protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_username);
      //get firebase auth instance
      auth = FirebaseAuth.getInstance();
      mName = (EditText) findViewById(R.id.name);
  
      btnSignUp = (TextView) findViewById(R.id.sign_up_button);
      final FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
      btnSignUp.setOnClickListener(new View.OnClickListener() {
          @Override
          public void onClick(View v) {
              auth = new FirebaseAuth.AuthStateListener() {
                  @Override
                  public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                      FirebaseUser user = firebaseAuth.getCurrentUser();
                  }
  
                  if(user!=null)
  
                  {
                      UserProfileChangeRequest profileUpdates = new UserProfileChangeRequest.Builder()
                              .setDisplayName(mName)
                              .build();
                      user.updateProfile(profileUpdates);
                      Intent intent = new Intent(UsernameActivity.this, JokeActivity.class);
                      startActivity(intent);
                  }
              };
          }
      });
  }}
  </code></pre>
  
  <p>Below is the image of what I want to achieve.</p>
  
  <p><img src="https://i.imgur.com/qVpLdwW.jpg" alt="EditText"></p>