Still raise "firebase_auth/email-already-in-use" exception, although registered an unique email in firebase_auth flutter - firebase

Question

I have a registration state that would handled registration of firebase authentication. From my code, there are two widgets. First (registerForm(context)), it shows registration forms. When "Register" Elevated Button is pressed, they will changed to second widgets (registerProcess(context)) there are processed a registrations.
import 'dart:io';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:connectivity/connectivity.dart';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:firebase_storage/firebase_storage.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:flutter/widgets.dart';
import 'package:path_provider/path_provider.dart';
class SignUp extends StatefulWidget {
static const routeName = "/signUp";
#override
_SignUpState createState() => _SignUpState();
}
class _SignUpState extends State<SignUp> {
final _emailController = TextEditingController();
final _passwordController = TextEditingController();
final _confirmPasswordController = TextEditingController();
final _nameController = TextEditingController();
final auth = FirebaseAuth.instance;
final fireStore = FirebaseFirestore.instance;
final storage = FirebaseStorage.instance;
bool isConnected = false;
bool passwordNotMatch = false;
bool networkWarning = false;
bool emailWarning = false;
bool isSignedUp;
#override
void initState() {
super.initState();
isSignedUp = false;
checkConnectivity();
}
Future<void> checkConnectivity() async {
var conRes = await Connectivity().checkConnectivity();
if (conRes != ConnectivityResult.none) {
isConnected = true;
}
}
Future<UserCredential> _signUp() async {
final validate = await auth.createUserWithEmailAndPassword(
email: _emailController.text,
password: _passwordController.text);
await auth.currentUser.sendEmailVerification();
final file = await getImgFromAssets("default.png");
await storage.ref("profile/${_emailController.text}.png").putFile(file);
return validate;
}
Future<File> getImgFromAssets(String path) async {
final byteData = await rootBundle.load('assets/$path');
final file = File('${(await getTemporaryDirectory()).path}/$path');
await file.writeAsBytes(byteData.buffer.asUint8List(byteData.offsetInBytes, byteData.lengthInBytes));
return file;
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: isSignedUp ? registerProcess(context) : registerForm(context));
}
Widget registerForm(BuildContext context) {
double height = MediaQuery.of(context).size.height;
// double width = MediaQuery.of(context).size.width;
return SafeArea(
child: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text("Sign Up",style: Theme.of(context).textTheme.headline4,),
SizedBox(height: height * 0.02,),
Padding(
padding: const EdgeInsets.all(16),
child: Column(
children: [
TextField(
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Profile Name',
),
controller: _nameController,
),
SizedBox(height: height * 0.02,),
TextField(
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Email Address',
),
controller: _emailController,
),
Row(
mainAxisAlignment: MainAxisAlignment.start,
children: [
Text("Note: Please be unique"),
],
),
emailWarning ? Text("Email is already used", style: TextStyle(color: Colors.red),)
: Container(),
SizedBox(height: height * 0.02,),
TextField(
obscureText: true,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Password',
),
controller: _passwordController,
),
passwordNotMatch ? Row(
mainAxisAlignment: MainAxisAlignment.start,
children: [
Text("Password Not Match", style: TextStyle(color: Colors.red),),
],
) : SizedBox(height: 0,),
SizedBox(height: height * 0.02,),
TextField(
obscureText: true,
decoration: InputDecoration(
border: OutlineInputBorder(),
labelText: 'Confirm Password',
),
controller: _confirmPasswordController,
),
ElevatedButton(
onPressed: () {
if (!isConnected) {
setState(() {
networkWarning = !networkWarning;
});
} else if (_confirmPasswordController.text != _passwordController.text) {
setState(() {
passwordNotMatch = !passwordNotMatch;
});
}
// else if(_confirmPasswordController.text == null || _passwordController.text == null){}
else {
setState(() {
isSignedUp = !isSignedUp;
});
}
},
child: Padding(
padding: const EdgeInsets.all(8.0),
child: Text("Register", style: TextStyle(fontSize: height * 0.025),),
),
),
],
),
),
],
),
),
);
}
Widget registerProcess(BuildContext context) {
return DefaultTextStyle(
style: Theme.of(context).textTheme.headline3,
textAlign: TextAlign.center,
child: FutureBuilder<UserCredential>(
future: _signUp(),
builder: (context, snapshot) {
List<Widget> children;
if (snapshot.hasData) {
children = <Widget>[
const Icon(
Icons.check_circle_outline,
color: Colors.green,
size: 60,
),
Padding(
padding: const EdgeInsets.only(top: 16),
child: Text('You\'re registered. Please check your email for verification'),
)
];
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: children,
),
);
} else if (snapshot.hasError) {
print(snapshot.error.toString());
children = <Widget>[
const Icon(
Icons.error_outline,
color: Colors.red,
size: 60,
),
Padding(
padding: const EdgeInsets.only(top: 16),
child: Text('Error: Email isn\'t valid or already use'),
)
];
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: children,
),
);
} else {
children = <Widget>[
SizedBox(
child: CircularProgressIndicator(),
width: 60,
height: 60,
),
Padding(
padding: EdgeInsets.only(top: 16),
child: Text('Awaiting result...'),
)
];
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: children,
),
);
}
}
)
);
}
}
Although I registered any unique email, it still raise an exception: [firebase_auth/email-already-in-use] The email address is already in use by another account. (Output from print(snapshot.error.toString())). I've checked at my firebase console repeatedly. Are there any mistakes?

Answer 1

Firebase is known for storing some cached data (including authentication and firestore data) in your device once you install the app and start using it's services.
In other words, it's very likely that you're getting this exception because you've deleted the user from firebase but the cached data (which firebase always checks first) is still in your device. Make sure that you really deleted the user in firebase, completely uninstall the app from your device, run flutter clean and then try again. Let me know if it works