Writing to Firebase Realtime Database with Flutter - firebase

Question

I've perused the forums, google, and youtube for info on writing data to a real-time database with flutter and haven't found a proper guide for even the most basic write.
That being said, in my app, I am currently trying to save the user's email to the database as a child of the user's new id. I am attempting to do this immediately after calling .createUserWithEmailAndPassword. This all should occur on click of a Material Button. I previously had the write inside of the then statement, but that was giving me an error.
Code:
FirebaseAuth userAuth = FirebaseAuth.instance;
void saveEmailInDb(String userId, String email) {
final userRef = FirebaseDatabase.instance.reference();
userRef.child(userId).child("Email").push().set(email);
}
//inside of the build widget
MaterialButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(32),
),
color: colorPalette.chooseColor('yellow'),
child: Container(
padding: EdgeInsets.all(13),
child: Text(
'Register',
style: GoogleFonts.ubuntu(
color: colorPalette.chooseColor('darkGrey'),
fontSize: 17),
),
),
onPressed: () async {
try {
UserCredential userCredential = await userAuth
.createUserWithEmailAndPassword(
email: tecEmail.text,
password: tecPassword.text)
.then(
(value) => Navigator.push(
context,
MaterialPageRoute(
builder: (context) => LoadingPage(),
),
),
);
saveEmailInDb(
userCredential.user.uid, tecEmail.text);
} on FirebaseAuthException catch (e) {
if (e.code == 'weak-password') {
print('The password provided is too weak.');
} else if (e.code == 'email-already-in-use') {
print('The account already exists for that email.');
}
} catch (e) {
print(e);
}
},
),
I have instantiated firebase in the main widget:
Future<void> main() async {
WidgetsFlutterBinding.ensureInitialized();
await Firebase.initializeApp();
runApp(
GetMaterialApp(
home: LoadingPage(),
),
);
}
Now, I know that flutter is hooked up properly to my app because an account is created in the firebase console under authentication. However, nothing is written to the database and as there are no proper guides or official documentation, I am unsure how to proceed.
Database Rules:
{
"rules": {
".read": true,
".write": true
}
}

Answer 1

Answer: Moving the navigation code outside of the then statement, and below the database write, was sufficient to solve this problem. Basically, the navigation was poping the widget before the database code was called. Revised code below:
MaterialButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(32),
),
color: colorPalette.chooseColor('yellow'),
child: Container(
padding: EdgeInsets.all(13),
child: Text(
'Register',
style: GoogleFonts.ubuntu(
color: colorPalette.chooseColor('darkGrey'),
fontSize: 17),
),
),
onPressed: () async {
try {
UserCredential userCredential =
await userAuth.createUserWithEmailAndPassword(
email: tecEmail.text,
password: tecPassword.text);
saveEmailInDb(userCredential.user.uid, tecEmail.text);
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => LoadingPage(),
),
);
} on FirebaseAuthException catch (e) {
if (e.code == 'weak-password') {
print('The password provided is too weak.');
} else if (e.code == 'email-already-in-use') {
print('The account already exists for that email.');
}
} catch (e) {
print(e);
}
},
),