Мое приложение не работает в симуляторе Android

Question

Итак, я разрабатываю приложение для чата и тестирую его на симуляторе android (вариант с пикселем 3). Но теперь я пытаюсь заставить его работать в другом эмуляторе (на этот раз я выбираю пиксель 2) и не запускается.

Я передам часть кода, включая MainActivity.

Это из LogCat

2020-01-28 01:47:27.799 10456-10456/com.example.textmefinal E/AndroidRuntime: FATAL EXCEPTION: main
Process: com.example.textmefinal, PID: 10456
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.textmefinal/com.example.textmefinal.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.google.firebase.auth.FirebaseUser.getUid()' on a null object reference
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3270)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409)
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135)
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016)
    at android.os.Handler.dispatchMessage(Handler.java:107)
    at android.os.Looper.loop(Looper.java:214)
    at android.app.ActivityThread.main(ActivityThread.java:7356)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930)
 Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.String com.google.firebase.auth.FirebaseUser.getUid()' on a null object reference
    at com.example.textmefinal.MainActivity.onCreate(MainActivity.java:44)
    at android.app.Activity.performCreate(Activity.java:7802)
    at android.app.Activity.performCreate(Activity.java:7791)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1299)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3245)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3409) 
    at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83) 
    at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:135) 
    at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:95) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2016) 
    at android.os.Handler.dispatchMessage(Handler.java:107) 
    at android.os.Looper.loop(Looper.java:214) 
    at android.app.ActivityThread.main(ActivityThread.java:7356) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:930) 

2020-01-28 01: 47: 57.456 10456-10494 / ком. Например

}

Активность входа

package com.example.textmefinal;

publi c Класс LoginActivity расширяет AppCompatActivity {

private FirebaseAuth mAuth;
private ProgressDialog loadingBar;


private Button LoginButton, PhoneLoginButton;
private EditText UserEmail, UserPassword;
private TextView NeedNewAccountLink, ForgetPasswordLink;

private DatabaseReference UsersRef;


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

    mAuth = FirebaseAuth.getInstance();
    UsersRef = FirebaseDatabase.getInstance().getReference().child("Users");

    InitializeFields();

    NeedNewAccountLink.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            SendUserToRegisterActivity();
        }
    });

    LoginButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            AllowUserToLogin();
        }
    });
}

@Override
protected void onStart()
            {
                super.onStart();

                FirebaseUser currentUser = mAuth.getCurrentUser();
                if (currentUser != null)
                    {
                        SendUserToMainActivity();
                    }
            }

private void AllowUserToLogin() {
    String email = UserEmail.getText().toString();
    String password = UserPassword.getText().toString();

    if (TextUtils.isEmpty(email)){
        Toast.makeText(this, "Please enter email...", Toast.LENGTH_SHORT).show();
    }
    if (TextUtils.isEmpty(password)){
        Toast.makeText(this, "Please enter password...", Toast.LENGTH_SHORT).show();
    }
    else {

        loadingBar.setTitle("Sign In");
        loadingBar.setMessage("Please wait...");
        loadingBar.setCanceledOnTouchOutside(true);
        loadingBar.show();

        mAuth.signInWithEmailAndPassword(email, password)
                .addOnCompleteListener(new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()){

                            String currentUserId = mAuth.getCurrentUser().getUid();
                            String deviceToken = FirebaseInstanceId.getInstance().getToken();

                            UsersRef.child(currentUserId).child("device_token")
                                    .setValue(deviceToken)
                                    .addOnCompleteListener(new OnCompleteListener<Void>() {
                                        @Override
                                        public void onComplete(@NonNull Task<Void> task) {
                                            if (task.isSuccessful())  {
                                                SendUserToMainActivity();
                                                Toast.makeText(LoginActivity.this, "Logged in Successful", Toast.LENGTH_SHORT).show();
                                                loadingBar.dismiss();
                                            }
                                        }
                                    });
                        }
                        else {
                            String message = task.getException().toString();
                            Toast.makeText(LoginActivity.this, "Error: " + message, Toast.LENGTH_SHORT).show();
                            loadingBar.dismiss();
                        }
                    }
                });
    }
}

private void InitializeFields() {
    LoginButton = (Button) findViewById(R.id.login_button);
    PhoneLoginButton = (Button) findViewById(R.id.phone_login_button);
    UserEmail = (EditText) findViewById(R.id.login_email);
    UserPassword = (EditText) findViewById(R.id.login_password);
    NeedNewAccountLink = (TextView) findViewById(R.id.need_new_account_link);
    ForgetPasswordLink = (TextView) findViewById(R.id.forget_password_link);
    loadingBar = new ProgressDialog(this);

}


private void SendUserToMainActivity() {
    Intent mainIntent = new Intent(LoginActivity.this, MainActivity.class);
    mainIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
    startActivity(mainIntent);
    finish();
}

private void SendUserToRegisterActivity() {
    Intent registerIntent = new Intent(LoginActivity.this, RegisterActivity.class);
    startActivity(registerIntent);
}

}

Регистрация активности

package com.example.textmefinal;

publi c Класс RegisterActivity расширяет AppCompatActivity {

private Button CreateAccountButton;
private EditText UserEmail, UserPassword;
private TextView AlreadyHaveAccountLink;

private FirebaseAuth mAuth;
private DatabaseReference RootRef;

private ProgressDialog loadingBar;

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

    mAuth = FirebaseAuth.getInstance();
    RootRef = FirebaseDatabase.getInstance().getReference();


    InitializeFields();


    AlreadyHaveAccountLink.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            SendUserToLoginActivity();
        }
    });

    CreateAccountButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            CreateNewAccount();
        }
    });
}

private void CreateNewAccount() {
    String email = UserEmail.getText().toString();
    String password = UserPassword.getText().toString();

    if (TextUtils.isEmpty(email)){
        Toast.makeText(this, "Please enter email...", Toast.LENGTH_SHORT).show();
    }
    if (TextUtils.isEmpty(password)){
        Toast.makeText(this, "Please enter password...", Toast.LENGTH_SHORT).show();
    }
    else {

        loadingBar.setTitle("Creating New Account");
        loadingBar.setMessage("Please wait, while we are creating new account for you...");
        loadingBar.setCanceledOnTouchOutside(true);
        loadingBar.show();

        mAuth.createUserWithEmailAndPassword(email, password)
                .addOnCompleteListener(new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (task.isSuccessful()){

                            String deviceToken = FirebaseInstanceId.getInstance().getToken();


                            String currentUserID = mAuth.getCurrentUser().getUid();
                            RootRef.child("Users").child(currentUserID).setValue("");

                            RootRef.child("Users").child(currentUserID).child("device_token")
                                    .setValue(deviceToken);

                            SendUserToMainActivity();
                            Toast.makeText(RegisterActivity.this, "Account Created Successfully...", Toast.LENGTH_SHORT).show();
                            loadingBar.dismiss();
                        }
                        else {
                            String message = task.getException().toString();
                            Toast.makeText(RegisterActivity.this, "Error: " + message, Toast.LENGTH_SHORT).show();
                            loadingBar.dismiss();
                        }
                    }
                });
    }
}

private void InitializeFields() {
    CreateAccountButton = (Button) findViewById(R.id.register_button);
    UserEmail = (EditText) findViewById(R.id.register_email);
    UserPassword = (EditText) findViewById(R.id.register_password);
    AlreadyHaveAccountLink = (TextView) findViewById(R.id.already_have_account_link);

    loadingBar = new ProgressDialog(this);
}

private void SendUserToLoginActivity() {
    Intent loginIntent = new Intent(RegisterActivity.this, LoginActivity.class);
    startActivity(loginIntent);
}

private void SendUserToMainActivity() {
    Intent mainIntent = new Intent(RegisterActivity.this, MainActivity.class);
    mainIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
    startActivity(mainIntent);
    finish();
}

}

Может кто угодно помогите мне?

введите описание изображения здесь

Answer 1

у вашего приложения TextMe есть некоторые проблемы с активностью запуска, поэтому оно запускает sh при запуске, пожалуйста, исправьте это ... или поделитесь журналами logcat, чтобы мы могли помочь.

Answer 2

Если вы щелкнете по вкладке «Выполнить» в нижней части редактора, вы, как правило, увидите сообщение, написанное красным, если приложение обнаружит исключение. В этом сообщении должно быть указано, какая ошибка была обнаружена.