How to Setup Firebase

You might need to use Firebase for the following reasons:

  1. Firebase authentication of users in your app via phone number.
  2. Firebase Cloud Messaging (FCM) push notifications (former GCM).

It might look a bit scary at first. But don’t panic and let's check how to do this right step by step.

Firebase account and project registration

Follow these steps to register your Firebase account and create a Firebase project:

  1. Register a Firebase account at Firebase console . You can use your Google account to authenticate at Firebase.

  2. Click Add project

    Adding Project in Firebase

    Note: If you have a Google project registered for your mobile app, select it from the Project name dropdown menu.

    You can also edit your Project ID if you need. A unique ID is assigned automatically to each project. This ID is used in publicly visible Firebase features. For example, it will be used in database URLs and in your Firebase Hosting subdomain. If you need to use a specific subdomain, you can change it.

  3. Fill in the fields required (Project name, Project ID, etc.) and click Continue.

    Add a project

  4. Select data sharing for your project and click Create project. We have chosen to allow only Technical Support access.

    Select data sharing

    Then click Continue.

    Click Continue

  5. Select platform for which you need Firebase

    Select platform

  6. Fill in the fields on Add Firebase to your Android App screen and click Register App

    Add Firebase to your Android app

Connect Firebase SDK

For Android projects Firebase has the following requirements to be added successfully:

  • Android OS 4.0 or newer
  • Google Play Services 15.0.0 or higher
  • The latest version of Android Studio

Here is a step by step guide how to connect Firebase SDK to your Android Project:

  1. Download Google-Services.json config file

    Download config file

  2. Open Project view in Android Studio and upload Google-Services.json file you have just downloaded into the root directory of your Android app module.

    Upload config file to your project

  3. Add Firebase SDK according to the instructions in your Firebase console

    Add Firebase SDK

  4. Add Google services plugin to your project build.gradle file

    Add Google services plugin to project

  5. Add Google services plugin in the bottom of your module build.gradle file.

    Add Google services plugin to module

  6. Click Sync Now at the pop-up in your Android Studio


    You are done now.

Firebase authentication

This option allows users in your app authenticate themselves via phone number. If you use this method for user authentication, the user receives an SMS with verification code and authenticates via that code in your app.

You need to follow these steps to add Firebase authentication to your Android project:

  1. Add Firebase authentication dependency to your Module build.gradle file:

    Add Firebase authentication dependency

  2. Sync your project as prompted by Android Studio:

    Sync your project

  3. Find your app’s SHA-1 hash - check Authenticating Your Client guide.

  4. Add your app’s SHA-1 hash in your Firebase console >> Project settings tab:

    Add your app's SHA-1 hash

    And then:

    Add your app's SHA-1 hash

  5. Go to Firebase console >> Authentication >> Sign-in method section:

    Enable phone authentication in Firebase

  6. Enable Phone number sign-in method:

    Enable phone authentication in Firebase

  7. Add PhoneAuthProvider.verifyPhoneNumber method to request that Firebase verify the user's phone number:

         phoneNumber,         // Phone number to verify
         60,                 // Timeout duration
         TimeUnit.SECONDS,    // Unit of timeout
         this,               // Activity (for callback binding)
         mCallbacks);        // OnVerificationStateChangedCallbacks

    Note: verifyPhoneNumber method is reentrant: if you call it multiple times, such as in an activity's onStart method, verifyPhoneNumber method will not send a second SMS unless the original request has timed out.

    Important note: As a best practice please do not forget to inform your users that if they use phone sign-in, they might receive an SMS message for verification and standard rates apply.

  8. (Optional) To resume the phone number sign in process if your app closes before the user can sign in (if the user checks SMS app, for instance), after verifyPhoneNumber method is called, set a flag that indicates verification is in progress. Then, save the flag in your Activity's onSaveInstanceState method and restore the flag in onRestoreInstanceState. In your Activity's onStart method, check if verification is already in progress, and if it is not, call verifyPhoneNumber again. Be sure to clear the flag when verification completes or fails. Check this guide for more details.

  9. setLanguageCode method on your Auth instance allows specifying the auth language and therefore localize SMS message sent by Firebase:

    // To apply the default app language instead of explicitly setting it.
    // auth.useAppLanguage();
  10. When you call PhoneAuthProvider.verifyPhoneNumber method, you must also provide an instance of OnVerificationStateChangedCallbacks, which contains implementations of the callback functions that handle the results of the request:

    mCallbacks = new PhoneAuthProvider.OnVerificationStateChangedCallbacks() {
    public void onVerificationCompleted(PhoneAuthCredential credential) {
        // This callback will be invoked in two situations:
        // 1 - Instant verification. In some cases the phone number can be instantly
        //     verified without needing to send or enter a verification code.
        // 2 - Auto-retrieval. On some devices Google Play services can automatically
        //     detect the incoming verification SMS and perform verification without
        //     user action.
        Log.d(TAG, "onVerificationCompleted:" + credential);
    public void onVerificationFailed(FirebaseException e) {
        // This callback is invoked in an invalid request for verification is made,
        // for instance if the the phone number format is not valid.
        Log.w(TAG, "onVerificationFailed", e);
        if (e instanceof FirebaseAuthInvalidCredentialsException) {
            // Invalid request
            // ...
        } else if (e instanceof FirebaseTooManyRequestsException) {
            // The SMS quota for the project has been exceeded
            // ...
        // Show a message and update the UI
        // ...
    public void onCodeSent(String verificationId,
                           PhoneAuthProvider.ForceResendingToken token) {
        // The SMS verification code has been sent to the provided phone number, we
        // now need to ask the user to enter the code and then construct a credential
        // by combining the code with a verification ID.
        Log.d(TAG, "onCodeSent:" + verificationId);
        // Save verification ID and resending token so we can use them later
        mVerificationId = verificationId;
        mResendToken = token;
        // ...
  11. Create a PhoneAuthCredential object using the verification code and the verification ID that was passed to onCodeSent callback. You get a PhoneAuthCredential object when onVerificationCompleted is called. To create PhoneAuthCredential object, call PhoneAuthProvider.getCredential:

    PhoneAuthCredential credential = PhoneAuthProvider.getCredential(verificationId, code);
  12. Complete the sign-in flow by passing the PhoneAuthCredential object to FirebaseAuth.signInWithCredential:

    private void signInWithPhoneAuthCredential(PhoneAuthCredential credential) {
            .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                public void onComplete(@NonNull Task<AuthResult> task) {
                    if (task.isSuccessful()) {
                        // Sign in success, update UI with the signed-in user's information
                        Log.d(TAG, "signInWithCredential:success");
                        FirebaseUser user = task.getResult().getUser();
                        // ...
                    } else {
                        // Sign in failed, display a message and update the UI
                        Log.w(TAG, "signInWithCredential:failure", task.getException());
                        if (task.getException() instanceof FirebaseAuthInvalidCredentialsException) {
                            // The verification code entered was invalid
  13. Get Firebase access_token after SMS code verification as follows:

    public Task<GetTokenResult> getIdToken (boolean forceRefresh)

    Example of the method implementation:

  14. Add ConnectyCube user sign in to your project as follows:

    1) Get your Project ID from your Firebase console:

    Get your Project ID

    2) Pass your Firebase project_id and Firebase access_token parameters to signInUsingFirebase method:

    String projectId = "...";
    String accessToken = "...";
    ConnectycubeUser user = ConnectycubeUsers.signInUsingFirebase(projectId, accessToken).performAsync(new EntityCallback<ConnectycubeUser>() {
      public void onSuccess(ConnectycubeUser user, Bundle args) {
      public void onError(ResponseException error) {
  15. Try running a test. Once your user is logged in successfully, you will find him/her in your Dashboard >> Your App >> Users section.

    User logged in

So now you know how to use Firebase features in your ConnectyCube apps. If you have any difficulties - please let us know via support channel