login page

import 'package:flutter/material.dart';
import 'package:auth/auth.dart';
import 'package:google_sign_in/google_sign_in.dart';

class LoginPage extends StatefulWidget {
  LoginPage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _LoginPageState createState() => _LoginPageState();
}

class _LoginPageState extends State<LoginPage> {

  GoogleSignIn _vanillaGoogleSignIn = GoogleSignIn(
    scopes: [
      'email',
      'https://www.googleapis.com/auth/contacts.readonly',
    ],
  );

  Future<void> _handleVanillaGoogleSignIn() async {
    try {
      await _vanillaGoogleSignIn.signIn();
      print(_vanillaGoogleSignIn.currentUser);
    } catch (error) {
      print(error);
    }
  }

  Auth auth;
  bool loggedIn = false;
  String errorMessage = "";
  bool test = false;

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

    auth = Auth.init(
      scopes: [
        'email',
        'https://www.googleapis.com/auth/contacts.readonly',
      ],
      /*
      listener: (user) {
        loggedIn = user != null;
        errorMessage = auth.message;
        setState(() {});
      },
       */
    );

/*
    auth.signInSilently(
      listen: (account) {
        loggedIn = account != null;
        errorMessage = auth.message;
        setState(() {});
      },
      listener: (user) {
        final test = user != null;
        print(test);
      },
    );
 */

    auth.isLoggedIn().then((isIn) {
      loggedIn = isIn;
    });
  }

  @override
  void dispose() {
    // Important to dispose of the Auth's resources.
    auth.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    const double _fontSize = 20.0;
    var screenSize = MediaQuery.of(context).size;
    var screenHeight = screenSize.height;
    return Scaffold(
      backgroundColor: Color.fromRGBO(58, 66, 86, 1.0),
      appBar: AppBar(
        elevation: 0.1,
        backgroundColor: Color.fromRGBO(58, 66, 86, 1.0),
        title: Text('Welcome to Score AI'),
      ),
      body: SafeArea(
        top: false,
        bottom: false,
        child: SingleChildScrollView(
          padding: EdgeInsets.all(50.0),
          child: Theme(
            data: ThemeData(
              brightness: Brightness.dark,
              inputDecorationTheme: InputDecorationTheme(
                // hintStyle: new TextStyle(color: Colors.blue, fontSize: 20.0),
                labelStyle: TextStyle(color: Colors.tealAccent, fontSize: 25.0),
              ),
            ),
            isMaterialAppTheme: true,
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              children: <Widget>[
                // Sized box
                SizedBox(height: screenHeight / 4),
                // Sign up with Facebook
                FlatButton(
                  padding: EdgeInsets.only(left: 20),
                  color: Color.fromRGBO(252, 252, 252, 1),
                  child: Row(
                    children: <Widget>[
                      Image.asset(
                        "images/facebook_logo.png",
                        width: (_fontSize * 1.618),
                        alignment: Alignment.centerLeft,
                      ),
                      Padding(
                        padding: const EdgeInsets.all(10.0),
                        child: Text(
                          "Continue with Facebook",
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontSize: _fontSize,
                            color: Color.fromRGBO(58, 66, 86, 1.0),
                          ),
                        ),
                      ),
                    ],
                  ),
                  onPressed: () {
                    auth.signInWithFacebook().then((value) {
                      if (value) {
                        Navigator.pushReplacementNamed(
                            context, 'datatablespage');
                      }
                    }).catchError((error) => print(error));
                  },
                ),
                // Sized box
                const SizedBox(height: _fontSize * 2),
                // Sign up with Google
                FlatButton(
                  padding: EdgeInsets.only(left: 20),
                  color: Color.fromRGBO(252, 252, 252, 1),
                  child: Row(
                    children: <Widget>[
                      Image.asset(
                        "images/google_logo.png",
                        width: (_fontSize * 1.618),
                        alignment: Alignment.centerLeft,
                      ),
                      Padding(
                        padding: const EdgeInsets.all(10.0),
                        child: Text(
                          "Continue with Google",
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontSize: _fontSize,
                            color: Color.fromRGBO(58, 66, 86, 1.0),
                          ),
                        ),
                      ),
                    ],
                  ),
                  onPressed: () {
                    auth.signInWithGoogle().then((value) {
                      if (value) {
                        print("google signin successfull...");
                        print(value);
                        Navigator.pushReplacementNamed(
                            context, 'datatablespage');
                        print(auth.signInProvider);
                      }
                    }).catchError((error) => print(error));
                    print(auth.message);
                  },
                ),
                // Sized box
                const SizedBox(height: _fontSize * 2),
                // Sign up with Google
                FlatButton(
                  padding: EdgeInsets.only(left: 20),
                  color: Color.fromRGBO(252, 252, 252, 1),
                  child: Row(
                    children: <Widget>[
                      Image.asset(
                        "images/google_logo.png",
                        width: (_fontSize * 1.618),
                        alignment: Alignment.centerLeft,
                      ),
                      Padding(
                        padding: const EdgeInsets.all(10.0),
                        child: Text(
                          "Vanilla Google",
                          textAlign: TextAlign.center,
                          style: TextStyle(
                            fontSize: _fontSize,
                            color: Color.fromRGBO(58, 66, 86, 1.0),
                          ),
                        ),
                      ),
                    ],
                  ),
                  onPressed: _handleVanillaGoogleSignIn,
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}