facebookAuthCredential.idToken is null in Flutter - firebase

Question

I successfully integrated facebook login in android and ios, I also getting facebook access token on login but getting null in token id. Below is the code
Future<UserCredential> signInWithFacebook() async {
// Trigger the sign-in flow
final LoginResult loginResult = await FacebookAuth.instance.login();
// Create a credential from the access token
final OAuthCredential facebookAuthCredential =
FacebookAuthProvider.credential(loginResult.accessToken!.token);
print(facebookAuthCredential.idToken); //Here getting null
// Once signed in, return the UserCredential
return FirebaseAuth.instance.signInWithCredential(facebookAuthCredential);
}

Answer 1

You won't get an idToken at this point with Facebook authentication flow, only accessToken. Use the following code skeleton to manage Facebook sign-in and evaluate the results at specific lines with breakpoints:
Future<UserCredential> signInWithFacebook() async {
final LoginResult loginResult = await FacebookAuth.instance.login();
if (loginResult.status == LoginStatus.success) {
final AccessToken accessToken = loginResult.accessToken!;
final OAuthCredential credential =
FacebookAuthProvider.credential(accessToken.token);
try {
return await FirebaseAuth.instance.signInWithCredential(credential);
} on FirebaseAuthException catch (e) {
// manage Firebase authentication exceptions
} catch (e) {
// manage other exceptions
}
} else {
// login was not successful, for example user cancelled the process
}
}
Then you can call this function with await, and once the future is completed, you can access user data:
final userCredential = await signInWithFacebook();
if (userCredential != null) {
// here you will have your Firebase user in:
// userCredential.user
final idToken = userCredential.user!.getIdToken();
}