如何在使用firebase和flutter登录和注册时发现身份验证错误

Question

我对flutter还很陌生，这是我第一个使用类似firebase的后端的项目。因此，我预先构建了一个ui，并开始在其中集成firebase，它已经成功完成，并且可以正常工作，但当我在登录注册时试图打印出错误时，我没有做到，我可以在控制台中捕捉到错误，但我等待用错误文本更新我的用户。当我试图登录时，尽管我提供了错误的密码，但它会把我带到我不想要的主页

这是我的登录页面，带有预构建的ui和登录的工作设置

import 'package:flutter/material.dart';
import 'package:notepad/Authentigation%20Screens/signUp.dart';
import 'package:notepad/animation/bouncypagetrans.dart';
import 'package:notepad/animation/fadeanimation.dart';
import 'package:notepad/auth/authMethod.dart';
import 'package:notepad/screens/homepage.dart';
import 'package:notepad/widgets/VxTextsHeaders.dart';
import 'package:notepad/widgets/customRaisedButton.dart';
import 'package:notepad/widgets/loading.dart';
import 'package:notepad/widgets/textformField.dart';
import 'ForgotPassword.dart';
class LogIn extends StatefulWidget {
@override
_LogInState createState() => _LogInState();
}
class _LogInState extends State<LogIn> {
String error;
AuthMethods authMethods = new AuthMethods();
bool isLoading = false;
final formKey = GlobalKey<FormState>();
TextEditingController emailTextEditingController =
new TextEditingController();
TextEditingController passwordTextEditingController =
new TextEditingController();
logMein()  {
if (formKey.currentState.validate()) {
try {
setState(() {
isLoading = true;
});
authMethods
.signInWithEmailAndPassword(emailTextEditingController.text,
passwordTextEditingController.text)
.then((val) {
// print("${val.uId}");
Navigator.pushReplacement(
context,
BouncyPageRout(
widget: HomePage(),
),
);
});
} catch (e) {
setState(() {
error = e.message;
});
}
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
resizeToAvoidBottomPadding: true,
body: isLoading
? Loading()
: SafeArea(
child: Container(
width: double.infinity,
padding: EdgeInsets.fromLTRB(30.0, 100.0, 30.0, 20.0),
height: MediaQuery.of(context).size.height,
child: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
FadeAnimation(
1.0,
headerTitle("Hello,"),
),
FadeAnimation(
2.0,
headerSubTitle("Log in to continue"),
),
],
),
SizedBox(height: 65),
Column(
children: [
Form(
key: formKey,
child: Column(children: [
SizedBox(height: 20),

FadeAnimation(
3.0,
buildTextField(
validator: (val) {
return val.isEmpty ||
RegExp(r"^[a-zA-Z0-9.a-zA-Z0-9.!#$%&'*+-/=?^_`{|}~]+@[a-zA-Z0-9]+.[a-zA-Z]+")
.hasMatch(val)
? null
: "Please provide a valid Email";
},
labelText: "Email",
controller: emailTextEditingController),
),
SizedBox(height: 20),
FadeAnimation(
3.5,
buildTextField(
validator: (val) {
return val.isEmpty || val.length < 6
? "Please Provide a Strong Password,/n Provide somthing greater than 6  "
: null;
},
labelText: "Password",
obscureText: true,
controller:
passwordTextEditingController),
),
])),
SizedBox(height: 10.0),
Container(
alignment: Alignment.centerRight,
child: FadeAnimation(
4.0,
InkWell(
onTap: () {
Navigator.push(
context,
BouncyPageRout(
widget: ForgotPassword(),
),
);
},
child: Text(
'Forgot Password?',
style: TextStyle(
fontWeight: FontWeight.bold,
color: Colors.deepOrange,
fontSize: 14),
),
),
),
),
SizedBox(height: 40),
FadeAnimation(
4.5,
raisedButton(
context: context,
onPressed: () {
logMein();
},
color: Colors.deepOrange,
title: "Log In",
textColor: Colors.white,
),
),
SizedBox(
height: 20.0,
),
FadeAnimation(
5.0,
raisedButton(
context: context,
onPressed: () {
Navigator.push(
context,
BouncyPageRout(
widget: SignUp(),
),
);
},
color: Colors.white,
title: "SignUp"),
),
],
)
],
),
),
),
),
);
}

}

AuthMethods页面包含firebase的所有代码

import 'package:notepad/auth/user.dart';
class AuthMethods {
String error;
final FirebaseAuth _auth = FirebaseAuth.instance;
User _userFromFirebaseUser(FirebaseUser user) {
return user != null ? User(userId: user.uid) : null;
}
Future signInWithEmailAndPassword(String email, String password) async {
try {
AuthResult result = await _auth.signInWithEmailAndPassword(
email: email, password: password);
FirebaseUser firebaseUser = result.user;
return _userFromFirebaseUser(firebaseUser);
} catch (e) {
print(e.toString());
}
}
Future signUpwithEmailAndPassword(String email, String password) async {
try {
AuthResult result = await _auth.createUserWithEmailAndPassword(
email: email, password: password);
FirebaseUser firebaseUser = result.user;
return _userFromFirebaseUser(firebaseUser);
} catch (e) {
print(e.toString());
}
}
Future resetPass(String email) async {
try {
return await _auth.sendPasswordResetEmail(email: email);
} catch (e) {
print(e.toString());
}
}
Future signOut() async {
try {
return await _auth.signOut();
} catch (e) {
print(e.toString());
}
}
}

所以基本上，我想通知我的用户一个有效的错误消息，直到他们解决了，他们不应该导航到一个特定的屏幕

Answer 1

您可以使用snackbar小部件并在抛出函数中调用它们！点击此链接了解有关小吃条的更多信息https://flutter.dev/docs/cookbook/design/snackbars