Login to Facebook using Firebase Auth : Developer Error

Question

I implement Login to Facebook using Firebase Auth in my android app using custom layout. It gives Developer error after Facebook upgrade graph API from 3.2 to 4.4. I follow the complete procedure .Create project to Firebase and Facebook developer console . enable Facebook login in Firebase authentication , add app id and app secret to Firebase . get oath URL and add to Facebook console. Also generate Openssl SHA for Facebook and add in it. here is my dependencies :

implementation 'com.firebaseui:firebase-ui-auth:4.3.1'
implementation 'com.google.firebase:firebase-core:16.0.9'
implementation 'com.google.firebase:firebase-auth:17.0.0'
implementation 'com.firebaseui:firebase-ui-database:4.3.1'
implementation 'com.facebook.android:facebook-android-sdk:5.0.0'
implementation "com.google.android.gms:play-services-auth:17.0.0"

this is code i did:

 AuthMethodPickerLayout customLayout = new AuthMethodPickerLayout
                .Builder(R.layout.activity_main)
                .setGoogleButtonId(R.id.ll_google)
                .setFacebookButtonId(R.id.ll_facebook)
                .setEmailButtonId(R.id.ll_email)
                // ...
                //.setTosAndPrivacyPolicyId(R.id.baz)

                .build();
        // Choose authentication providers
        List<AuthUI.IdpConfig> providers = Arrays.asList(
                new AuthUI.IdpConfig.EmailBuilder().build(),
                new AuthUI.IdpConfig.GoogleBuilder().build(),
                new AuthUI.IdpConfig.FacebookBuilder().build());


        AuthUI.getInstance()
                .createSignInIntentBuilder()
                .setIsSmartLockEnabled(false)
                .setLogo(R.drawable.icon)
                .setAuthMethodPickerLayout(customLayout)
                .setTosAndPrivacyPolicyUrls("https://mybrandfitness.com/terms-conditions",
                        "https://mybrandfitness.com/privacy-policy")
                .build();

llFacebook.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                AuthUI.IdpConfig facebookIdp = new AuthUI.IdpConfig.FacebookBuilder()
                        .setPermissions(Arrays.asList("email", "public_profile"))
                        .build();

                startActivityForResult(
                        AuthUI.getInstance()
                                .createSignInIntentBuilder()
                                .setAvailableProviders(Arrays.asList(facebookIdp))
                                .build(),
                        RC_SIGN_IN);
            }
        });

it gives me following error:

E/AuthUI: A sign-in error occurred.
com.firebase.ui.auth.FirebaseUiException: Developer error
    at com.firebase.ui.auth.util.data.ProviderUtils$1.then(ProviderUtils.java:219)
    at com.firebase.ui.auth.util.data.ProviderUtils$1.then(ProviderUtils.java:195)
    at com.google.android.gms.tasks.zzf.run(Unknown Source)
    at android.os.Handler.handleCallback(Handler.java:739)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:145)
    at android.app.ActivityThread.main(ActivityThread.java:5951)
    at java.lang.reflect.Method.invoke(Native Method)
    at java.lang.reflect.Method.invoke(Method.java:372)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1399)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1194)

any suggestion will be appreciated ..thank you

Answer 1

First, open the ProviderUtils.java:219 and you will see that the login was successful, but it raised exception for the case: There is an existing user who only has unsupported sign in methods.

if (task.isSuccessful() && lastSignedInProviders.isEmpty()
                            && !methods.isEmpty()) {
                        // There is an existing user who only has unsupported sign in methods
                        return Tasks.forException(new FirebaseUiException(ErrorCodes
                                .DEVELOPER_ERROR));
                    }

So, i guess that the email (of your facebook account) you're using to signing was used to login into your app before with other login method, ex: user and password.

• Try with other facebook account to see if it works
• Delete the account with that email and try again