flutter_facebook_auth

Flutter plugin to make easy the facebook authentication in your flutter app. iOS and Android is supported.

install on Android

Go to https://developers.facebook.com/docs/facebook-login/android/?locale=en and read the next documentation.

  • Edit Your Resources and Manifest
  • Associate Your Package Name and Default Class with Your App
  • Provide the Development and Release Key Hashes for Your App

install on iOS

Configure Info.plist

<key>CFBundleURLTypes</key>
<array>
  <dict>
    <key>CFBundleURLSchemes</key>
    <array>
      <string>fb{your-app-id}</string>
    </array>
  </dict>
</array>
<key>FacebookAppID</key>
<string>{your-app-id}</string>
<key>FacebookDisplayName</key>
<string>{your-app-name}</string>
<key>LSApplicationQueriesSchemes</key>
<array>
  <string>fbapi</string>
  <string>fb-messenger-share-api</string>
  <string>fbauth2</string>
  <string>fbshareextension</string>
</array>

METHODS

fisrt create a new instance of FacebookAuth. NOTE: all methods are asynchronous.

  • .login({List<String> permissions = const ['email', 'public_profile'] }) : request login with a list of permissions.

    The public_profile permission allows you read the next fileds id, first_name, last_name, middle_name, name, name_format, picture, short_name

    For more info go to https://developers.facebook.com/docs/facebook-login/permissions/

    return one instance of LoginResult class:

      { 
        status: 200,
        accessToken: { 
          expires: 1573493493209, 
          declinedPermissions: [], 
          permissions: [public_profile, email], 
          userId: 3003332493073668, 
          token: EAAVDwBAE5lndhpg17DHFZABzh6QKiAZC42Qljcub9gib52L5CPEXvhk2ZBEa7LlOuyastmmkZBfwP7dKW6Xi4tvrTw8DToO2M2kMcau6CXsYtyys7WZAWV3XaMPnhuVauo5ghtGpnhJvZAtMKqlsgbV5GklPAYZD
        }
      }
    

    if status is 200 the login was successfull.

  • .logOut() : close the current facebook session.

  • .isLogged() : check if the user has an active facebook session. The response will be null if the user is not logged. return one instance of AccessToken class:

      { 
          expires: 1573493493209, 
          declinedPermissions: [], 
          permissions: [public_profile, email], 
          userId: 3003332493073668, 
          token: EAATaHWA7VDwBAE5lndhpg17DHFZABzh6QKiAZC42Qljcub9gib52L5CPEXvhk2ZBEa7LlOuytmmkZBfwP7dKW6Xi4XCO2M2kMcau6CXsYtyys7WZAWV3XaMPnhuVauo5ghtGpnhJvZAtMKqlsgbV5GklPAYZD
        }
    

    NOTE: declinedPermissions and permissions are null on iOS, please use the method permissionsStatus(String token)

  • .getUserData({String fields = "name,email,picture"}) : get the user info only if the user is logged.

    Expected response:

      {
      email = "dsmr.apps@gmail.com";
      id = 3003332493073668;
      name = "Darwin Morocho";
      picture =     {
          data =         {
              height = 50;
              "is_silhouette" = 0;
              url = "https://platform-lookaside.fbsbx.com/platform/profilepic/?asid=3003332493073668&height=50&width=50&ext=1570917120&hash=AeQMSBD5s4QdgLoh";
              width = 50;
          };
      };
      }
    

EXAMPLE

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_facebook_auth/flutter_facebook_auth.dart';

void main() => runApp(MyApp());

class MyApp extends StatefulWidget {
  @override
  _MyAppState createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  final _fb = FacebookAuth();
  dynamic _userData;
  String _token;

  @override
  void initState() {
    super.initState();
    _checkIfIsLogged();
  }

  _printCredentials(AccessToken accessToken) {
    _token = accessToken.token;
    print("userId: ${accessToken.userId}");
    print("token: $_token");
    print("expires: ${accessToken.expires}");
    print("permissions: ${accessToken.permissions.toString()}");
  }

  _checkIfIsLogged() async {
    final accessToken = await _fb.isLogged();
    if (accessToken != null) {
      _printCredentials(accessToken);
      // now you can call to  _fb.getUserData();
      final userData = await _fb.getUserData();
      // final userData = await _fb.getUserData(fields:"email,birthday");
      setState(() {
        _userData = userData;
      });
    }
  }

  _login() async {
    final result = await _fb.login();
    // final result = await _fb.login(permissions:['email','user_birthday']);
    print("login result ${result.toString()}");
    if (result.status == 200) {
      _printCredentials(result.accessToken);
      // get the user data
      final userData = await _fb.getUserData();
      // final userData = await _fb.getUserData(fields:"email,birthday");
      setState(() {
        _userData = userData;
      });
    } else if (result.status == 403) {
      print("login cancelled");
    } else {
      print("login failed");
    }
  }

  _logOut() async {
    await _fb.logOut();
    _token = null;
    setState(() {
      _userData = null;
    });
  }

  _checkPermissions() async {
    final dynamic response = await _fb.permissionsStatus(_token);
    print("permissions: ${response.toString()}");
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Facebook Auth Example'),
        ),
        body: Column(
          crossAxisAlignment: CrossAxisAlignment.center,
          children: <Widget>[
            Text(_userData != null ? _userData.toString() : "NO LOGGED"),
            _userData != null
                ? CupertinoButton(
                    child: Text("Check permissions"),
                    onPressed: _checkPermissions,
                    color: Colors.greenAccent,
                  )
                : Container(),
            SizedBox(height: 20),
            CupertinoButton(
                color: Colors.blue,
                child: Text(
                  _userData != null ? "LOGOUT" : "LOGIN",
                  style: TextStyle(color: Colors.white),
                ),
                onPressed: _userData != null ? _logOut : _login),
          ],
        ),
      ),
    );
  }
}

Using with firebase_auth

Just create a credential like

 // this line do auth in firebase with your facebook credential.
 AuthCredential credential =  FacebookAuthProvider.getCredential(accessToken: _token);
            

final FirebaseUser user = (await _auth.signInWithCredential(credential)).user;

Libraries

flutter_facebook_auth