Menautkan Beberapa Penyedia Autentikasi ke Akun di Android
Tetap teratur dengan koleksi
Simpan dan kategorikan konten berdasarkan preferensi Anda.
Anda dapat mengizinkan pengguna untuk login ke aplikasi Anda menggunakan beberapa penyedia
autentikasi, dengan menautkan kredensial penyedia autentikasi ke akun pengguna yang ada.
Pengguna bisa diidentifikasi dengan ID pengguna Firebase yang sama, apa pun penyedia autentikasi yang digunakan untuk login. Misalnya, pengguna yang login dengan sandi bisa menautkan Akun Google dan login dengan salah satu metode tersebut di lain waktu. Atau, seorang pengguna anonim bisa menautkan akun Facebook, kemudian login dengan Facebook untuk melanjutkan penggunaan aplikasi Anda.
Sebelum memulai
Tambahkan dukungan untuk dua penyedia autentikasi atau lebih (mungkin dengan menyertakan autentikasi anonim) ke aplikasi Anda.
Menautkan kredensial penyedia autentikasi ke akun pengguna
Untuk menautkan kredensial penyedia autentikasi ke akun pengguna yang ada:
Proses login pengguna menggunakan penyedia atau metode autentikasi apa pun.
Selesaikan alur login untuk penyedia autentikasi baru hingga, tetapi tidak termasuk, tahap pemanggilan salah satu metode FirebaseAuth.signInWith. Misalnya,
dapatkan token ID Google, token akses Facebook, atau email dan sandi pengguna.
Dapatkan AuthCredential untuk penyedia autentikasi baru:
Panggilan ke linkWithCredential akan gagal jika kredensial sudah ditautkan ke akun pengguna lain. Dalam situasi ini, Anda harus menangani
penggabungan akun dan data terkait dengan cara yang sesuai untuk aplikasi Anda:
Kotlin
valprevUser=auth.currentUserauth.signInWithCredential(credential).addOnSuccessListener{result->
valcurrentUser=result.user// Merge prevUser and currentUser accounts and data// ...}.addOnFailureListener{// ...}
FirebaseUserprevUser=FirebaseAuth.getInstance().getCurrentUser();mAuth.signInWithCredential(credential).addOnCompleteListener(newOnCompleteListener<AuthResult>(){@OverridepublicvoidonComplete(@NonNullTask<AuthResult>task){FirebaseUsercurrentUser=task.getResult().getUser();// Merge prevUser and currentUser accounts and data// ...}});
Jika panggilan ke linkWithCredential berhasil, pengguna kini dapat login menggunakan
penyedia autentikasi yang ditautkan dan mengakses data Firebase yang sama.
Membatalkan tautan penyedia autentikasi dari akun pengguna
Anda dapat membatalkan tautan penyedia autentikasi dengan akun, sehingga pengguna tidak dapat login lagi dengan penyedia tersebut.
Untuk membatalkan link penyedia autentikasi dari akun pengguna, teruskan ID penyedia ke
metode unlink. Anda bisa mendapatkan ID penyedia dari penyedia autentikasi
yang ditautkan ke pengguna dengan memanggil getProviderData.
Kotlin
Firebase.auth.currentUser!!.unlink(providerId).addOnCompleteListener(this){task->
if(task.isSuccessful){// Auth provider unlinked from account// ...}}
[null,null,["Terakhir diperbarui pada 2025-08-21 UTC."],[],[],null,["| **Important** : There is a [known issue](https://github.com/firebase/firebase-js-sdk/issues/7675) that prevents `linkWithCredentials()` from working correctly in some projects. See the issue report for a workaround and the status of a fix.\n\nYou can allow users to sign in to your app using multiple authentication\nproviders by linking auth provider credentials to an existing user account.\nUsers are identifiable by the same Firebase user ID regardless of the\nauthentication provider they used to sign in. For example, a user who signed in\nwith a password can link a Google account and sign in with either method in the\nfuture. Or, an anonymous user can link a Facebook account and then, later, sign\nin with Facebook to continue using your app.\n\nBefore you begin\n\nAdd support for two or more authentication providers (possibly including\nanonymous authentication) to your app.\n\nLink auth provider credentials to a user account\n\nTo link auth provider credentials to an existing user account:\n\n1. Sign in the user using any authentication provider or method.\n2. Complete the sign-in flow for the new authentication provider up to, but not including, calling one of the [`FirebaseAuth.signInWith`](/docs/reference/android/com/google/firebase/auth/FirebaseAuth#public-method-summary) methods. For example, get the user's Google ID token, Facebook access token, or email and password.\n3. Get a `AuthCredential` for the new authentication provider:\n\n Google Sign-In \n\n Kotlin \n\n ```kotlin\n val credential = GoogleAuthProvider.getCredential(googleIdToken, null)https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/MainActivity.kt#L394-L394\n ```\n\n Java \n\n ```java\n AuthCredential credential = GoogleAuthProvider.getCredential(googleIdToken, null);https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/MainActivity.java#L479-L479\n ```\n\n Facebook Login \n\n Kotlin \n\n ```kotlin\n val credential = FacebookAuthProvider.getCredential(token.token)https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/MainActivity.kt#L401-L401\n ```\n\n Java \n\n ```java\n AuthCredential credential = FacebookAuthProvider.getCredential(token.getToken());https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/MainActivity.java#L487-L487\n ```\n\n Email-password sign-in \n\n Kotlin \n\n ```kotlin\n val credential = EmailAuthProvider.getCredential(email, password)https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/MainActivity.kt#L409-L409\n ```\n\n Java \n\n ```java\n AuthCredential credential = EmailAuthProvider.getCredential(email, password);https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/MainActivity.java#L495-L495\n ```\n4. Pass the `AuthCredential` object to the signed-in user's\n `linkWithCredential` method:\n\n Kotlin \n\n ```kotlin\n auth.currentUser!!.linkWithCredential(credential)\n .addOnCompleteListener(this) { task -\u003e\n if (task.isSuccessful) {\n Log.d(TAG, \"linkWithCredential:success\")\n val user = task.result?.user\n updateUI(user)\n } else {\n Log.w(TAG, \"linkWithCredential:failure\", task.exception)\n Toast.makeText(\n baseContext,\n \"Authentication failed.\",\n Toast.LENGTH_SHORT,\n ).show()\n updateUI(null)\n }\n }https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/AnonymousAuthActivity.kt#L66-L81\n ```\n\n Java \n\n ```java\n mAuth.getCurrentUser().linkWithCredential(credential)\n .addOnCompleteListener(this, new OnCompleteListener\u003cAuthResult\u003e() {\n @Override\n public void onComplete(@NonNull Task\u003cAuthResult\u003e task) {\n if (task.isSuccessful()) {\n Log.d(TAG, \"linkWithCredential:success\");\n FirebaseUser user = task.getResult().getUser();\n updateUI(user);\n } else {\n Log.w(TAG, \"linkWithCredential:failure\", task.getException());\n Toast.makeText(AnonymousAuthActivity.this, \"Authentication failed.\",\n Toast.LENGTH_SHORT).show();\n updateUI(null);\n }\n }\n });https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/AnonymousAuthActivity.java#L91-L106\n ```\n\n The call to `linkWithCredential` will fail if the credentials are\n already linked to another user account. In this situation, you must handle\n merging the accounts and associated data as appropriate for your app: \n\n Kotlin \n\n ```kotlin\n val prevUser = auth.currentUser\n auth.signInWithCredential(credential)\n .addOnSuccessListener { result -\u003e\n val currentUser = result.user\n // Merge prevUser and currentUser accounts and data\n // ...\n }\n .addOnFailureListener {\n // ...\n }https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/MainActivity.kt#L250-L259\n ```\n\n Java \n\n ```java\n FirebaseUser prevUser = FirebaseAuth.getInstance().getCurrentUser();\n mAuth.signInWithCredential(credential)\n .addOnCompleteListener(new OnCompleteListener\u003cAuthResult\u003e() {\n @Override\n public void onComplete(@NonNull Task\u003cAuthResult\u003e task) {\n FirebaseUser currentUser = task.getResult().getUser();\n // Merge prevUser and currentUser accounts and data\n // ...\n }\n });https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/MainActivity.java#L303-L312\n ```\n\nIf the call to `linkWithCredential` succeeds, the user can now sign in using\nany linked authentication provider and access the same Firebase data.\n\nUnlink an auth provider from a user account\n\nYou can unlink an auth provider from an account, so that the user can no\nlonger sign in with that provider.\n\nTo unlink an auth provider from a user account, pass the provider ID to the\n`unlink` method. You can get the provider IDs of the auth providers\nlinked to a user by calling [`getProviderData`](/docs/reference/android/com/google/firebase/auth/FirebaseUser#getProviderData()). \n\nKotlin \n\n```kotlin\nFirebase.auth.currentUser!!.unlink(providerId)\n .addOnCompleteListener(this) { task -\u003e\n if (task.isSuccessful) {\n // Auth provider unlinked from account\n // ...\n }\n }https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/MainActivity.kt#L265-L271\n```\n\nJava \n\n```java\nmAuth.getCurrentUser().unlink(providerId)\n .addOnCompleteListener(this, new OnCompleteListener\u003cAuthResult\u003e() {\n @Override\n public void onComplete(@NonNull Task\u003cAuthResult\u003e task) {\n if (task.isSuccessful()) {\n // Auth provider unlinked from account\n // ...\n }\n }\n });https://github.com/firebase/snippets-android/blob/cc307b137a106d66a52fa6e9bee6f4f55dab9f76/auth/app/src/main/java/com/google/firebase/quickstart/auth/MainActivity.java#L321-L330\n```\n\nTroubleshooting\n\nIf you encounter errors when trying to link multiple accounts, see the\n[documentation on\nverified email addresses](https://firebase.google.com/docs/auth/users#verified_email_addresses)."]]
