FirabaseAuth can't catch exception in Flutter - firebase

Question

I'm working on a signup screen for my app. I implemented firebase and can authenticate user and save some user info into firebase database succesfully. I started to check if userName field is empty or not. But firebase sometimes can not catch exception about bad formatted email address. It works for password (min 6 char) everytime but sometimes work for email. I can't find any solution. Here is my code. Is there anybody who have an idea?
onPressed: () async {
if (validateName(userName) && validateEmail(email)) {
setState(() {
showSpinner = true;
});
try {
final newUser =
await _auth.createUserWithEmailAndPassword(
email: email, password: password);
if (newUser != null) {
//get name and update user profile
UserUpdateInfo userUpdateInfo = UserUpdateInfo();
userUpdateInfo.displayName = userName;
FirebaseUser user = await _auth.currentUser();
await user.updateProfile(userUpdateInfo);
await user.reload();
Navigator.pushNamed(context, NavigationScreen.id);
}
setState(() {
showSpinner = false;
});
} on PlatformException catch (e) {
setState(() {
showSpinner = false;
});
Fluttertoast.showToast(
msg: e.message,
toastLength: Toast.LENGTH_SHORT,
gravity: ToastGravity.CENTER,
timeInSecForIosWeb: 3,
backgroundColor: Colors.white,
textColor: Colors.red,
fontSize: 18.0,
);
}
} else {
Fluttertoast.showToast(
msg: 'You must ente all information',
toastLength: Toast.LENGTH_SHORT,
gravity: ToastGravity.CENTER,
timeInSecForIosWeb: 3,
backgroundColor: Colors.white,
textColor: Colors.red,
fontSize: 18.0,
);
}
},
//name TextField validation
bool validateName(String name) {
if (name != null && name.length > 2) {
return true;
} else {
return false;
}
}
//email TextField validation
bool validateEmail(String email) {
if (email != null) {
return true;
} else {
return false;
}
}

Answer 1

createUserWithEmailAndPassword returns a Future<AuthResult>, to catch the error you can do the following:
final newUser = await _auth.createUserWithEmailAndPassword(email: email, password: password).catchError((err) {
showDialog(
context: context,
builder: (BuildContext context) {
return AlertDialog(
title: Text("Error"),
content: Text(err.message),
actions: [
FlatButton(
child: Text("Ok"),
onPressed: () {
Navigator.of(context).pop();
},
)
],
);
});
Using catchError, it will handles errors emitted by this Future, and then showDialog will display a dialog with the error.