如何解决 facebookauthprovider 中缺少的位置参数？

Question

i am using a github project to learn flutter and firebase, but i can figure out what the below 2 errors represent and how to solve them can someone please help

code:

try {
  final FacebookLoginResult facebookLoginResult =
  await fbLogin.logIn(['email']);
  if (facebookLoginResult.status == FacebookLoginStatus.loggedIn) {
    FacebookAccessToken facebookAccessToken =
        facebookLoginResult.accessToken;
    AuthCredential credential = FacebookAuthProvider.credential(
        accessToken: facebookAccessToken.token);
    User user = (await auth.signInWithCredential(credential)).user;
    print("signed in" + user.displayName);
    return user;
  }

Errors in Dart analysis tab:

error: 1 positional argument(s) expected, but 0 found. (not_enough_positional_arguments at [flutter_app] lib\login_page.dart:32)

error: The named parameter 'accessToken' isn't defined. (undefined_named_parameter at [flutter_app] lib\login_page.dart:33)

the issue is in this section of the code:

        AuthCredential credential = FacebookAuthProvider.credential(
        accessToken: facebookAccessToken.token);

Answer 1

You are facing this error because FacebookAuthProvider.credential() does not taking any named parameter instead it takes a single positional argument accessToken .

Replace your line of code with this

AuthCredential credential = 
FacebookAuthProvider.credential(facebookAccessToken.token);