Flutter stay logged in with phone number - firebase

Question

How can I register with a phone number and stay logged in until I log out. I'm using flutter and I already can register a user with a phone number but when the app is re-opened it starts at the login page.
The idea is to stay logged in after sign-up and even after app closed. and I also can't make circular Indicator to show that the app is loading (I would love it if you showed me how to do this as well)
Here is my code.
import 'package:country_code_picker/country_code_picker.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:flutter/material.dart';
import 'BottomBarPages/home.dart';
class SignIn extends StatefulWidget {
#override
_SignInState createState() => _SignInState();
}
class _SignInState extends State<SignIn> {
TextEditingController phoneController = new TextEditingController();
String phoneNumber = "";
bool shower = false;
String smsCode;
String verificationCode;
void _onCountryChange(CountryCode countryCode) {
this.phoneNumber = countryCode.toString();
print("New Country selected: " + countryCode.toString());
}
void check() {
final myPhone = this.phoneNumber + phoneController.text;
print("Full Text: " + myPhone);
}
Future<void> man() async{
}
Future<void> submit() async {
final myPhone = this.phoneNumber + phoneController.text;
final PhoneVerificationCompleted verificationCompleted =
(AuthCredential credential) {
setState(() {
print(credential);
});
};
final PhoneVerificationFailed verificationFailed =
(AuthException exception) {};
final PhoneCodeSent phoneCodeSent = (String verId, [int forceCodeResend]) {
this.verificationCode = verId;
smsCodeDialog(context).then((value) => print("signed"));
};
final PhoneCodeAutoRetrievalTimeout autoRetrievalTimeout = (String verId) {
this.verificationCode = verId;
};
await FirebaseAuth.instance.verifyPhoneNumber(
phoneNumber: myPhone,
timeout: const Duration(seconds: 5),
verificationCompleted: verificationCompleted,
verificationFailed: verificationFailed,
codeSent: phoneCodeSent,
codeAutoRetrievalTimeout: autoRetrievalTimeout);
}
Future<bool> smsCodeDialog(BuildContext context) {
return showDialog(
context: context,
barrierDismissible: false,
builder: (BuildContext context) {
return AlertDialog(
title: Text(
'Enter Code',
style: TextStyle(color: Colors.lightGreen, fontSize: 24),
),
content: TextField(
keyboardType: TextInputType.number,
onChanged: (Value) {
smsCode = Value;
},
),
contentPadding: EdgeInsets.all(10),
actions: [
FlatButton(
onPressed: () {
FirebaseAuth.instance.currentUser().then((user) {
if (user != null) {
Navigator.of(context).pop();
Navigator.push(context,
MaterialPageRoute(builder: (context) => Home()));
} else {
Navigator.of(context).pop();
signIn();
}
});
},
child: Text(
'Verify',
style: TextStyle(fontSize: 20, color: Colors.lightGreen),
))
],
);
});
// CircularProgressIndicator(
// valueColor: new AlwaysStoppedAnimation<Color>(Colors.lightGreen),
// value: 0.25,
// );
}
signIn() {
AuthCredential phoneAuthCredential = PhoneAuthProvider.getCredential(
verificationId: verificationCode, smsCode: smsCode);
FirebaseAuth.instance
.signInWithCredential(phoneAuthCredential)
.then((user) => Navigator.push(
context, MaterialPageRoute(builder: (context) => Home())))
.catchError((e) => print(e));
}
#override
Widget build(BuildContext context) {
return GestureDetector(
onTap: () {
FocusScopeNode currentFocus = FocusScope.of(context);
if (!currentFocus.hasPrimaryFocus) {
currentFocus.unfocus();
}
},
child: Scaffold(
body: Column(
//mainAxisAlignment: MainAxisAlignment.start,
children: [
Expanded(
flex: 1,
child: Container(
height: MediaQuery.of(context).size.height,
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.topLeft,
end: Alignment.bottomRight,
stops: [0.1, 0.3, 1.0],
colors: [
Colors.lightGreen[300],
Colors.white,
Colors.lightGreen[50]
],
),
),
child: Padding(
padding: const EdgeInsets.symmetric(vertical: 15),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
SizedBox(
height: 150,
child: Image.asset('images/phone.png'),
),
SizedBox(
height: 20,
),
Padding(
padding: const EdgeInsets.symmetric(horizontal: 20),
child: Container(
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(50),
border: Border.all(color: Colors.lightGreen)),
width: double.infinity,
height: 40,
child: Padding(
padding: const EdgeInsets.symmetric(horizontal: 30),
child: Row(
// crossAxisAlignment: CrossAxisAlignment.start,
//mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: [
CountryCodePicker(
dialogTextStyle: TextStyle(fontSize: 20),
onChanged: _onCountryChange,
initialSelection: 'US',
favorite: ['+251', 'ET'],
),
Padding(
padding: const EdgeInsets.only(bottom: 10),
child: SizedBox(
width: 150,
child: TextFormField(
controller: phoneController,
keyboardType: TextInputType.phone,
decoration: InputDecoration(
border: InputBorder.none,
),
),
),
),
],
),
),
),
),
SizedBox(
height: 20,
),
MaterialButton(
onPressed: submit,
minWidth: MediaQuery.of(context).size.width - 80,
height: 45,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20)),
color: Colors.lightGreen,
splashColor: Colors.green,
child: Text(
"Confirm",
style: TextStyle(color: Colors.white, fontSize: 18),
),
),
Padding(
padding:
EdgeInsets.symmetric(vertical: 14, horizontal: 64),
child: Text(
"you'll receive a 6 digit code click Confirm to verify",
textAlign: TextAlign.center,
style: TextStyle(
fontSize: 22,
color: Colors.lightGreen,
),
),
),
],
),
),
),
),
],
),
),
);
}
}
Please help me.

Answer 1

When your application opens, check if the user is already logged in or not using:
User user = FirebaseAuth.instance.currentUser;
if user is not null then you should navigate the app to the home or some other screen. Try this code:
#override
void initState() {
super.initState();
getUser();
}
getUser() {
User firebaseUser = FirebaseAuth.instance.currentUser;
if (firebaseUser != null)
WidgetsBinding.instance.addPostFrameCallback((_) =>
Navigator.pushReplacement(
context, MaterialPageRoute(builder: (context) => HomePage())));
}