在 Android 中与 Firebase 连接时出错 找不到 com.google.firebase.auth 的本地模块描述符 class

Question

Total newbie here creating his first android app. I am trying to use firebase for authentication in an android app. I keep getting a Local module descriptor class for com.google.firebase.auth not found. Error when trying to register a new user

build.gradle(Project)

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath "com.android.tools.build:gradle:4.0.1"
        classpath "com.google.gms:google-services:4.3.3"
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

build.gradle(app)

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.0"

    defaultConfig {
        applicationId "com.example.encryptedchat"
        minSdkVersion 21
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: "libs", include: ["*.jar"])
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'androidx.constraintlayout:constraintlayout:1.1.3'

    // firebase
    implementation 'com.google.firebase:firebase-auth:19.3.2'
    implementation 'com.google.firebase:firebase-database:19.3.1'

    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'

}

AuthActivity.java

public class AuthActivity extends AppCompatActivity {

    private EditText username, email, password, confirm_password;
    private Button register_button;

    FirebaseAuth auth;
    DatabaseReference reference;

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

        username = findViewById(R.id.username);
        email = findViewById(R.id.email);
        password = findViewById(R.id.password);
        confirm_password = findViewById(R.id.confirmPassword);
        register_button = findViewById(R.id.registerButton);

        register_button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String str_username = username.getText().toString();
                String str_email = email.getText().toString();
                String str_password = password.getText().toString();
                String str_confirm_password = confirm_password.getText().toString();
                createAccount(str_username, str_email, str_password);
            }
        });

    }

    private void createAccount(final String uname, String emailaddr, String pswd) {
        System.out.println(uname);
        System.out.println(emailaddr);
        System.out.println(pswd);
        try {
            auth.createUserWithEmailAndPassword(emailaddr, pswd).addOnCompleteListener(new OnCompleteListener<AuthResult>() {

                @Override
                public void onComplete(@NonNull Task<AuthResult> task) {
                    System.out.println(task);
                    if (task.isSuccessful()) {
                        System.out.println("inside task successful");

                        FirebaseUser firebaseUser = auth.getCurrentUser();
                        assert firebaseUser != null;
                        String userId = firebaseUser.getUid();
                        reference = FirebaseDatabase.getInstance().getReference("Users").child(userId);

                        HashMap<String, String> hashMap = new HashMap<>();
                        hashMap.put("id", userId);
                        hashMap.put("username", uname);
                        hashMap.put("imgURL", "default");

                        reference.setValue(hashMap).addOnCompleteListener(new OnCompleteListener<Void>() {
                            @Override
                            public void onComplete(@NonNull Task<Void> task) {
                                if (task.isSuccessful()) {
                                    Intent intent = new Intent(AuthActivity.this, MainActivity.class);
                                    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
                                    startActivity(intent);
                                    finish();
                                }
                            }
                        });
                    } else {
                        Toast.makeText(AuthActivity.this, "Some error occurred...", Toast.LENGTH_SHORT).show();
                    }
                }
            });
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

Error Log

2020-08-21 22:09:28.683 22674-22674/com.example.encryptedchat I/e.encryptedcha: [GL_OOM] ClampGrowthLimit 268435456
2020-08-21 22:09:28.702 22674-22712/com.example.encryptedchat W/DynamiteModule: Local module descriptor class for com.google.firebase.auth not found.
2020-08-21 22:09:28.705 22674-22674/com.example.encryptedchat I/FirebaseInitProvider: FirebaseApp initialization successful
2020-08-21 22:09:28.706 22674-22674/com.example.encryptedchat V/Font: Change font:2
2020-08-21 22:09:28.706 22674-22674/com.example.encryptedchat V/Font: Default family:android.graphics.Typeface@a21ca01a
2020-08-21 22:09:28.711 22674-22716/com.example.encryptedchat E/Perf: Fail to get file list com.example.encryptedchat
2020-08-21 22:09:28.711 22674-22716/com.example.encryptedchat E/Perf: getFolderSize() : Exception_1 = java.lang.NullPointerException: Attempt to get length of null array
2020-08-21 22:09:28.711 22674-22716/com.example.encryptedchat E/Perf: Fail to get file list com.example.encryptedchat
2020-08-21 22:09:28.711 22674-22716/com.example.encryptedchat E/Perf: getFolderSize() : Exception_1 = java.lang.NullPointerException: Attempt to get length of null array
2020-08-21 22:09:28.716 22674-22715/com.example.encryptedchat W/DynamiteModule: Local module descriptor class for com.google.firebase.auth not found.
2020-08-21 22:09:28.720 22674-22715/com.example.encryptedchat I/FirebaseAuth: [FirebaseAuth:] Preparing to create service connection to gms implementation

I don't understand why its throwing a NullPointerException. All values are read and passed suucessfully.

Error Log

I/System.out: john
I/System.out: john@mail.con
    pass123
W/System.err: java.lang.NullPointerException: Attempt to invoke virtual method 'com.google.android.gms.tasks.Task com.google.firebase.auth.FirebaseAuth.createUserWithEmailAndPassword(java.lang.String, java.lang.String)' on a null object reference
W/System.err:     at com.example.encryptedchat.AuthActivity.createAccount(AuthActivity.java:71)
        at com.example.encryptedchat.AuthActivity.access$400(AuthActivity.java:25)
        at com.example.encryptedchat.AuthActivity$1.onClick(AuthActivity.java:59)
        at android.view.View.performClick(View.java:7201)
        at android.view.View.performClickInternal(View.java:7170)
        at android.view.View.access$3500(View.java:806)
        at android.view.View$PerformClick.run(View.java:27562)
        at android.os.Handler.handleCallback(Handler.java:883)
W/System.err:     at android.os.Handler.dispatchMessage(Handler.java:100)
        at android.os.Looper.loop(Looper.java:214)
        at android.app.ActivityThread.main(ActivityThread.java:7682)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:516)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:950)

Help will be appreciated Thanks

Answer 1

You forgot to initialize your auth variable. You need to set

auth = FirebaseAuth.getInstance();

You can do this wherever as long as auth is initialized when it's referenced. I personally would put it in the onCreate(...) method.