login_screen.dart

import 'dart:ui';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter_google_sign_in_demo/View_Model/sign_in_view_model.dart';
import 'package:flutter_google_sign_in_demo/base/base_view.dart';
import 'package:flutter_google_sign_in_demo/splash.dart';
import 'package:flutter_google_sign_in_demo/utils/routeNames.dart';
import 'package:flutter_google_sign_in_demo/utils/util.dart';
import 'package:flutter_google_sign_in_demo/utils/view_state.dart';
import 'package:google_sign_in/google_sign_in.dart';



class LoginScreen extends StatefulWidget{

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

class _LoginScreenState extends State<LoginScreen>{


  GlobalKey<FormState> _userLoginFormKey = GlobalKey();
  FirebaseUser _user;
  final FirebaseAuth _auth = FirebaseAuth.instance;
  final GoogleSignIn _googleSignIn = GoogleSignIn();

  bool isSignIn =false;
  bool google =false;


  @override
  Widget build(BuildContext context) {

    return BaseView<SignInViewModel>(
        onModelReady: (model) {},
        builder: (context, model, build) {
          return WillPopScope(
            child: SafeArea(
              child: Scaffold(
                backgroundColor: Color(0xFFE6E6E6),
                body: Stack(
                  children: <Widget>[
                    Container(
                      height: 410,
                      width: 430,
                      decoration: BoxDecoration(
                        image: DecorationImage(
                          image: AssetImage('assets/background.png'),
                          fit: BoxFit.contain,
                        ),
                      ),

                    ),
                    SingleChildScrollView(
                      child:Column(
                        children: <Widget>[
                          Container(
                            height: deviceSize.height/2.4,
                            width: deviceSize.width/3,
                            decoration: BoxDecoration(
                              image: DecorationImage(
                                image:
                                AssetImage('assets/weddinglogo.png'),
                              ),),),

                          Container(
                            child: Form(
                              key: _userLoginFormKey,
                              child: Padding(
                                padding: const EdgeInsets.only(top:5.0,bottom:15,left: 10,right: 10),
                                child: Card(
                                  shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20.0)),
                                  child: Column(
                                    children: <Widget>[
                                      Padding(
                                        padding: const EdgeInsets.all(15.0),
                                        child: Text("Login",style:TextStyle(fontWeight: FontWeight.w800,fontSize: 25),),
                                      ),
                                      Padding(
                                        padding: const EdgeInsets.only(top:15.0,right: 14,left: 14,bottom: 8),
                                        child: TextFormField(
                                          controller: model.userIdController,
                                          style: TextStyle(color: Colors.black,fontWeight:FontWeight.bold,fontSize: 15),
                                          decoration: InputDecoration(
                                            border: OutlineInputBorder(
                                              borderRadius: BorderRadius
                                                  .all(
                                                  Radius.circular(15)),
                                            ),
                                            hintText: "Email",
                                            hintStyle: TextStyle(fontSize: 15) ,
                                            contentPadding: EdgeInsets.fromLTRB(20.0, 15.0, 20.0, 15.0),
                                          ),
                                          cursorColor:Colors.black,
                                          keyboardType: TextInputType.emailAddress,
                                          inputFormatters: [
                                            BlacklistingTextInputFormatter
                                                .singleLineFormatter,
                                          ],),),
                                      Padding(
                                        padding: const EdgeInsets.only(top:5.0,right: 14,left: 14,bottom: 8),
                                        child: TextFormField(
                                          controller: model.passwordController,
                                          obscureText: !model.passwordVisible,
                                          style: TextStyle(color: Colors.black,fontWeight:FontWeight.bold,fontSize: 15),
                                          decoration: InputDecoration(
                                            border: OutlineInputBorder(
                                              borderRadius: BorderRadius
                                                  .all(
                                                  Radius.circular(15)),
                                            ),
                                            hintText: "Password",
                                            contentPadding: EdgeInsets.fromLTRB(20.0, 15.0, 20.0, 15.0),
                                            hintStyle: TextStyle(fontSize: 15) ,
                                            suffixIcon: IconButton(
                                                icon: Icon(model
                                                    .passwordVisible
                                                    ? Icons.visibility
                                                    : Icons.visibility_off,color: Color(0xFFE6E6E6),),
                                                onPressed: () {
                                                  model.passwordVisible =
                                                  !model
                                                      .passwordVisible;
                                                }),),
                                          cursorColor:Colors.black,
                                          inputFormatters: [
                                            BlacklistingTextInputFormatter
                                                .singleLineFormatter,
                                          ],),),
                                      SizedBox(height: 16,),
                                      InkWell(
                                        child: Container(
                                            width: deviceSize
                                                .width/2,
                                            height: deviceSize.height/18,
                                            margin: EdgeInsets.only(top: 25),
                                            decoration: BoxDecoration(
                                                borderRadius: BorderRadius.circular(20),
                                                color:Colors.black
                                            ),
                                            child: Center(
                                                child: Row(
                                                  mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                                                  children: <Widget>[
                                                    Container(
                                                      height: 30.0,
                                                      width: 30.0,
                                                      decoration: BoxDecoration(
                                                        image: DecorationImage(
                                                            image:
                                                            AssetImage('assets/google.jpg'),
                                                            fit: BoxFit.cover),
                                                        shape: BoxShape.circle,
                                                      ),
                                                    ),
                                                    Text('Sign in with Google',
                                                      style: TextStyle(
                                                          fontSize: 16.0,
                                                          fontWeight: FontWeight.bold,
                                                          color: Colors.white
                                                      ),
                                                    ),
                                                  ],
                                                )
                                            )
                                        ),
                                        onTap: ()
                                        async{
                                          signInWithGoogle(model)
                                              .then((FirebaseUser user){
                                            model.clearAllModels();
                                            Navigator.of(context).pushNamedAndRemoveUntil
                                              (RouteName.Home, (Route<dynamic> route) => false
                                            );}
                                            ).catchError((e) => print(e));
                                          },
                                      ),
                                      SizedBox(height: 16,),
                                    ],),
                                ),),
                            ),),
                        ],),
                    ),

                    model.state==ViewState.Busy
                        ? Utils.progressBar()
                        : Container(),
                  ],
                ),

              ),
            ),
            onWillPop: () async {
              model.clearAllModels();
              return false;
            },
          );
        }
    );
  }


  Future<FirebaseUser> signInWithGoogle(SignInViewModel model) async {
    model.state =ViewState.Busy;

    GoogleSignInAccount googleSignInAccount = await _googleSignIn.signIn();

    GoogleSignInAuthentication googleSignInAuthentication =

    await googleSignInAccount.authentication;

    AuthCredential credential = GoogleAuthProvider.getCredential(

      accessToken: googleSignInAuthentication.accessToken,

      idToken: googleSignInAuthentication.idToken,

    );

    AuthResult authResult = await _auth.signInWithCredential(credential);

    _user = authResult.user;

    assert(!_user.isAnonymous);

    assert(await _user.getIdToken() != null);

    FirebaseUser currentUser = await _auth.currentUser();

    assert(_user.uid == currentUser.uid);


    model.state =ViewState.Idle;

    print("User Name: ${_user.displayName}");
    print("User Email ${_user.email}");

  }
}