flutter problem : how to navigate to homepage from login - flutter

Question

When I clicking on login then every time showing an error occurs in dialog box
but in my debug console my shown login successfully
I do not understand why login is not happening, it is throwing catch error again and again
While my login in deb console is succesfully
And after login should go to homepage.
this is my auth.dart
import 'dart:async';
import 'dart:convert';
import 'package:flutter/cupertino.dart';
import 'package:rest_api_login/utils/api.dart';
import 'package:http/http.dart' as http;
import 'package:rest_api_login/utils/http_exception.dart';
import 'package:shared_preferences/shared_preferences.dart';
class Auth with ChangeNotifier {
var MainUrl = Api.authUrl;
var AuthKey = Api.authKey;
// String _token;
String _uid;
String _username;
DateTime _expiryDate;
Timer _authTimer;
bool get isAuth {
return token != null;
}
String get token {
if (_expiryDate != null &&
_expiryDate.isAfter(DateTime.now()) &&
_uid != null) {
return _uid;
}
}
String get uid {
return _uid;
}
String get username {
return _username;
}
Future<void> logout() async {
_username = null;
_uid = null;
_expiryDate = null;
if (_authTimer != null) {
_authTimer.cancel();
_authTimer = null;
}
notifyListeners();
final pref = await SharedPreferences.getInstance();
pref.clear();
}
void _autologout() {
if (_authTimer != null) {
_authTimer.cancel();
}
final timetoExpiry = _expiryDate.difference(DateTime.now()).inSeconds;
_authTimer = Timer(Duration(seconds: timetoExpiry), logout);
}
Future<bool> tryautoLogin() async {
final pref = await SharedPreferences.getInstance();
if (!pref.containsKey('userData')) {
return false;
}
final extractedUserData =
json.decode(pref.getString('userData')) as Map<String, Object>;
final expiryDate = DateTime.parse(extractedUserData['expiryDate']);
if (expiryDate.isBefore(DateTime.now())) {
return false;
}
_uid = extractedUserData['uid'];
_username = extractedUserData['username'];
_expiryDate = expiryDate;
notifyListeners();
_autologout();
return true;
}
Future<void> Authentication(
String username, String password, String endpoint) async {
try {
var url = Uri.parse('$MainUrl&action=$endpoint');
final responce = await http.post(url,
body: ({
'username': username,
'password': password,
}));
final responceData = json.decode(responce.body);
print(responceData);
if (responceData['error'] != null) {
throw HttpException(responceData['error']['msg']);
}
_uid = responceData['uid'];
_username = responceData['username'];
_expiryDate = DateTime.now()
.add(Duration(seconds: int.parse(responceData['expiresIn'])));
_autologout();
notifyListeners();
final prefs = await SharedPreferences.getInstance();
final userData = json.encode({
'uid': _uid,
'username': _username,
'expiryDate': _expiryDate.toIso8601String(),
});
prefs.setString('userData', userData);
print('check' + userData.toString());
} catch (e) {
throw e;
}
}
Future<void> login(String username, String password) {
return Authentication(username, password, 'login');
}
Future<void> signUp(String username, String password) {
return Authentication(username, password, 'registration');
}
}
This is my login.dart page
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:rest_api_login/providers/auth.dart';
import 'package:rest_api_login/screens/home_Screen.dart';
import 'package:rest_api_login/screens/signup_screen.dart';
import 'package:rest_api_login/utils/http_exception.dart';
class LoginScreen extends StatefulWidget {
static const String routeName = "/login";
#override
_LoginScreenState createState() => _LoginScreenState();
}
class _LoginScreenState extends State<LoginScreen> {
final GlobalKey<FormState> _formKey = GlobalKey();
Map<String, String> _authData = {'username': '', 'password': ''};
Future _submit() async {
if (!_formKey.currentState.validate()) {
//invalid
return;
}
_formKey.currentState.save();
try {
await Provider.of<Auth>(context, listen: false)
.login(_authData['username'], _authData['password']);
} on HttpException catch (e) {
var errorMessage = 'Authentication Failed';
if (e.toString().contains('INVALID_EMAIL')) {
errorMessage = 'Invalid email';
_showerrorDialog(errorMessage);
} else if (e.toString().contains('EMAIL_NOT_FOUND')) {
errorMessage = 'This email not found';
_showerrorDialog(errorMessage);
} else if (e.toString().contains('INVALID_PASSWORD')) {
errorMessage = 'Invalid Password';
_showerrorDialog(errorMessage);
}
} catch (error) {
var errorMessage = 'Plaese try again later';
_showerrorDialog(errorMessage);
}
}
#override
Widget build(BuildContext context) {
// TODO: implement build
return Scaffold(
// backgroundColor: Colors.white,
body: SingleChildScrollView(
child: Container(
child: Stack(
children: <Widget>[
Container(
height: MediaQuery.of(context).size.height * 0.65,
width: MediaQuery.of(context).size.width * 0.85,
decoration: BoxDecoration(
borderRadius: BorderRadius.only(
topRight: Radius.circular(360),
bottomRight: Radius.circular(360)),
color: Colors.blue),
),
Container(
padding:
EdgeInsets.only(top: 50, left: 20, right: 20, bottom: 50),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
"Sign In",
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 40),
),
SizedBox(
height: 10,
),
Text(
"Sign in with your username or email",
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 10),
),
Form(
key: _formKey,
child: Container(
padding: EdgeInsets.only(top: 50, left: 20, right: 20),
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(
"Username or Email",
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 12),
),
TextFormField(
style: TextStyle(color: Colors.white),
decoration: InputDecoration(
enabledBorder: UnderlineInputBorder(
borderSide: BorderSide(color: Colors.white),
),
focusedBorder: UnderlineInputBorder(
borderSide: BorderSide(color: Colors.white),
),
prefixIcon: Icon(
Icons.person,
color: Colors.white,
)),
// validator: (value) {
// if (value.isEmpty || !value.contains('#')) {
// return 'Invalid email';
// }
// },
onSaved: (value) {
_authData['username'] = value;
},
),
SizedBox(
height: 10,
),
Text(
"Password",
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 12),
),
TextFormField(
obscureText: true,
style: TextStyle(color: Colors.white),
decoration: InputDecoration(
enabledBorder: UnderlineInputBorder(
borderSide: BorderSide(color: Colors.white),
),
focusedBorder: UnderlineInputBorder(
borderSide: BorderSide(color: Colors.white),
),
prefixIcon: Icon(
Icons.vpn_key,
color: Colors.white,
)),
validator: (value) {
if (value.isEmpty || value.length < 5) {
return 'Password is to Short';
}
},
onSaved: (value) {
_authData['password'] = value;
},
),
Container(
padding: EdgeInsets.only(top: 40),
width: 140,
child: RaisedButton(
onPressed: () {
_submit();
},
shape: RoundedRectangleBorder(
borderRadius:
new BorderRadius.circular(10.0),
),
child: Text(
'Sign In',
style: TextStyle(color: Colors.white),
),
color: Colors.green),
),
Align(
alignment: Alignment.bottomRight,
child: InkWell(
onTap: () {
Navigator.of(context).push(MaterialPageRoute(
builder: (ctx) => SignUpScreen()));
},
child: Container(
padding: EdgeInsets.only(top: 90),
child: Text(
"Create Account",
style: TextStyle(
decoration: TextDecoration.underline,
color: Colors.blue,
fontSize: 16),
),
),
),
)
],
),
),
),
],
),
),
],
),
),
),
);
}
void _showerrorDialog(String message) {
showDialog(
context: context,
builder: (ctx) => AlertDialog(
title: Text(
'An Error Occurs',
style: TextStyle(color: Colors.blue),
),
content: Text(message),
actions: <Widget>[
FlatButton(
child: Text('Okay'),
onPressed: () {
Navigator.of(context).pop();
},
)
],
),
);
}
}
This is my main.dart page
import 'package:flutter/material.dart';
import 'package:login_and_signup/Providers/auth.dart';
import 'package:login_and_signup/Providers/signup_auth.dart';
import 'package:login_and_signup/Screens/home_screen.dart';
import 'package:login_and_signup/Screens/login.dart';
import 'package:login_and_signup/Screens/splash_screen.dart';
import 'package:provider/provider.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return ChangeNotifierProvider.value(
value: Auth(),
child: Consumer<Auth>(
builder: (context, auth, _) => MaterialApp(
title: 'Flutter demo',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity),
//home: LoginScreen(),
home: auth.isAuth!
? HomeScreen()
: FutureBuilder(
future: auth.tryautoLogin(),
builder: (context, snapshot) =>
snapshot.connectionState == ConnectionState.waiting
? SplashScreen()
: LoginScreen()),
),
),
);
}
}
This is my homepage.dart page
import 'package:flutter/material.dart';
import 'package:login_and_signup/Providers/auth.dart';
import 'package:login_and_signup/Screens/login.dart';
// import 'package:login_signup_with_api/Providers/auth.dart';
import 'package:provider/provider.dart';
class HomeScreen extends StatefulWidget {
#override
_HomeScreenState createState() => _HomeScreenState();
}
class _HomeScreenState extends State<HomeScreen> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Home"),
),
body: Center(
child: RaisedButton(
onPressed: () {
Navigator.of(context).pushReplacementNamed('/');
Provider.of<Auth>(context, listen: false).logout();
},
shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(10)),
child: Text('logout'),
color: Colors.green,
)
// color: Colors.green,
// ),
),
);
}
}