I had the same issue - it looks like we re working from the same tutorial (I m new at this too). For me, the problem was the SHA certificate fingerprints in Firebase - if you haven t set them up then the sign in simply won t do anything. In the terminals tab I could see that sign-in simply cancels itself.

为了解决这个问题,我这样做了:

• Set up my Key file (keystore - yes initially I forgot to do this!)
• Added my keystore file to the Android folder
• Created a key.properties file in Android/app/ folder
• Added my dependencies for the file in Android/app/build.gradle
• From terminal window run android/gradlew.bat
• Then in the same window run "gradlew signingReport" - this will give you SHA1 and SHA256 keys
• Go in to firebase console, project, settings, general, andorid apps and enter the SHA certificate fingerprints that grade gave you.

然后重建,它应该发挥作用。

在我的案件中,我在4个月前增加了消防基地的关键点,现在我试图做一些改动,但不能签署。

而且,如果你不使用安乐施室及其数据,但只保留密码,那么情况也会发生,现在,你需要重新生成你 de的钥匙,并将其添加到火库中。

<代码>现在,所需步骤是创建新的脱硫钥匙,添加到火基上。

<>说明:在许多情况下,这不是主要原因,而是给它一个尝试<>。

In my case, I have forgot to add dependency at project-level build.gradle and app-level. When adding android and ios app through Firebase CLI.

<>strong>auth.dart

import  dart:io ;

import  package:cloud_firestore/cloud_firestore.dart ;
import  package:flutter/material.dart ;
import  package:flutter/services.dart ;
import  package:firebase_auth/firebase_auth.dart ;
import  package:fluttertoast/fluttertoast.dart ;
import  package:google_sign_in/google_sign_in.dart ;
import  package:shared_preferences/shared_preferences.dart ;

abstract class BaseAuth {

  Future<String> signInWithGoogle();

//optional if you need to store user data
  String name = "User";
  String email = "Demo";
  String imageUrl = "https://celebritypets.net/wp-content/uploads/2016/12/Adriana-Lima.jpg";


}
enum authProblems { UserNotFound, PasswordNotValid, NetworkError }

class Auth implements BaseAuth {

final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
final GoogleSignIn googleSignIn = GoogleSignIn();

  Future<String> signInWithGoogle() async {


  final GoogleSignInAccount googleSignInAccount = await googleSignIn.signIn();
  final GoogleSignInAuthentication googleSignInAuthentication =
      await googleSignInAccount.authentication;

  final AuthCredential credential = GoogleAuthProvider.getCredential(
    accessToken: googleSignInAuthentication.accessToken,
    idToken: googleSignInAuthentication.idToken,
  );

  final AuthResult authResult = await _firebaseAuth.signInWithCredential(credential);
  final FirebaseUser user = authResult.user;

  // Checking if email and name is null
  assert(user.email != null);
  assert(user.displayName != null);
  assert(user.photoUrl != null);

  name = user.displayName;
  email = user.email;
  imageUrl = user.photoUrl;


  // Only taking the first part of the name, i.e., First Name
  if (name.contains(" ")) {
    name = name.substring(0, name.indexOf(" "));
  }

  assert(!user.isAnonymous);
  assert(await user.getIdToken() != null);

  final FirebaseUser currentUser = await _firebaseAuth.currentUser();
  assert(user.uid == currentUser.uid);

  return  signInWithGoogle succeeded: $user ;
}

authprovider.dart

import  package:flutter/material.dart ;
import  package:multitask_flutter/auth.dart ;

class AuthProvider extends InheritedWidget {

  AuthProvider({Key key,Widget child, this.auth}) : super(key: key,child: child);
  final BaseAuth auth;


  @override
  bool updateShouldNotify(InheritedWidget oldWidget) => true;

  static AuthProvider of(BuildContext context) {
    return context.dependOnInheritedWidgetOfExactType<AuthProvider>();
  }

}

loginpage.dart

import  package:appname_flutter/authprovider.dart ;
//just call this... when user click on button...

var auth = AuthProvider.of(context).auth;
auth.handleSignIn();

And You Done...

希望会有所助益。