Flutter：ユーザーのログインを維持し、ログアウトする方法
Csrfトークンを取得してコンソールに応答データを出力していますが、応答データを使用してユーザーをログインさせたままにする方法です。ステータスコードを使用してログインを作成しています。ユーザーがログインし、ログアウトしたい場合にのみログアウトする
多くの例を見てきましたが、私の場合は何も助けになりません。
私の場合、csrfトークンを使用していて、それをログイン状態に保つことができず、ログインフォームも使用しています。
LoginPage.Dart
import 'Dart:io';
import 'package:cookie_jar/cookie_jar.Dart';
import 'package:dio/dio.Dart';
import 'package:flutter/material.Dart';
import 'package:flutter/services.Dart';
import 'package:jignasa/home_screen.Dart';
import 'package:jignasa/logindata.Dart';
import 'package:path_provider/path_provider.Dart';
class LoginPage extends StatefulWidget {
static String tag = 'login-page';
@override
_LoginPageState createState() => new _LoginPageState();
}
class _LoginPageState extends State<LoginPage> {
final GlobalKey<FormState> _formKey = GlobalKey<FormState>();
LoginRequestData _loginData = LoginRequestData();
bool _validate = false;
bool _obscureText = true;
var username, password;
@override
Widget build(BuildContext context) {
return Scaffold(
// backgroundColor: Colors.white,
body: SingleChildScrollView(
child: Container(
color: Colors.lightGreen[500],
child: Column(
children: <Widget>[
Center(
child: Container(
width: MediaQuery
.of(context)
.size
.width,
height: MediaQuery
.of(context)
.size
.height / 2.5,
decoration: BoxDecoration(
gradient: LinearGradient(
// begin: Alignment.topCenter,
// end: Alignment.bottomCenter,
colors: [
Color(0xFFFFFFFF),
Color(0xFFFFFFFF),
]
),
borderRadius: BorderRadius.only(
bottomLeft: Radius.circular(90)
)
),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Align(
alignment: Alignment.center,
child: Image.asset('images/ic_launcher1.png'),
),
],
),
),
),
Center(
child: SingleChildScrollView(
child: new Form(
key: _formKey,
autovalidate: _validate,
child: _getFormUI(),
),
)
)
],
),
),
),
);
}
Widget _getFormUI() {
return new Column(
children: <Widget>[
SizedBox(height: 24.0),
Center(
child: Text('Login',
style: TextStyle(fontSize: 25,
fontWeight: FontWeight.bold,
color: Colors.white),),
),
new SizedBox(height: 25.0),
new TextFormField(
keyboardType: TextInputType.emailAddress,
autofocus: false,
decoration: InputDecoration(
hintText: 'Username',
contentPadding: EdgeInsets.fromLTRB(20.0, 15.0, 20.0, 15.0),
border:
OutlineInputBorder(borderRadius: BorderRadius.circular(32.0)),
),
validator: _validateName,
onSaved: (value) {
_loginData.username = value;
},
),
new SizedBox(height: 8.0),
new TextFormField(
autofocus: false,
obscureText: _obscureText,
keyboardType: TextInputType.text,
decoration: InputDecoration(
hintText: 'Password',
contentPadding: EdgeInsets.fromLTRB(20.0, 10.0, 20.0, 10.0),
border:
OutlineInputBorder(borderRadius: BorderRadius.circular(24.0)),
suffixIcon: GestureDetector(
child: Icon(
_obscureText ? Icons.visibility : Icons.visibility_off,
semanticLabel:
_obscureText ? 'show password' : 'hide password',
),
),
),
validator: _validatePassword,
onSaved: (String value) {
_loginData.password = value;
}
),
new SizedBox(height: 15.0),
new Padding(
padding: EdgeInsets.symmetric(vertical: 16.0),
child: RaisedButton(
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(24),
),
onPressed: () {
_submit();
// Navigator.of(context).pushReplacementNamed('/home');
},
padding: EdgeInsets.all(12),
color: Colors.black54,
child: Text('Log In', style: TextStyle(color: Colors.white)),
),
),
new FlatButton(
child: Text(
'Forgot password?',
style: TextStyle(color: Colors.black54),
),
onPressed: () {},
),
new FlatButton(
onPressed: _sendToRegisterPage,
child: Text('Not a member? Sign up now',
style: TextStyle(color: Colors.black54)),
),
Text(''),
Text(''),
Text(''),
],
);
}
_sendToRegisterPage() {
Navigator.Push(
context,
MaterialPageRoute(builder: (context) => HomeScreen()),
);
}
String _validateName(String value) {
if (value.isEmpty) {
return "Username is Required";
} else {
username = value.toString();
}
}
String _validatePassword(String value) {
if (value.isEmpty) {
return "Password is Required";
} else {
password = value.toString();
}
}
_submit() {
if (_formKey.currentState.validate()) {
_formKey.currentState.save();
print("Username ${_loginData.username}");
print("Password ${_loginData.password}");
return SessionId();
} else {
setState(() {
bool _validate = false;
});
}
}
final Dio _dio = Dio();
PersistCookieJar persistentCookies;
final String url = "https://www.xxxx.in/rest/user/login.json";
Future<String> get _localPath async {
final directory = await getApplicationDocumentsDirectory();
print(directory.path);
return directory.path;
}
Future<Directory> get _localCoookieDirectory async {
final path = await _localPath;
final Directory dir = new Directory('$path/cookies');
await dir.create();
print(dir);
return dir;
}
Future<String> getCsrftoken() async{
try {
String csrfTokenValue;
final Directory dir = await _localCoookieDirectory;
final cookiePath = dir.path;
persistentCookies = new PersistCookieJar(dir: '$cookiePath');
persistentCookies.deleteAll(); //clearing any existing cookies for a fresh start
_dio.interceptors.add(
CookieManager(persistentCookies) //this sets up _dio to persist cookies throughout subsequent requests
);
_dio.options = new BaseOptions(
baseUrl: url,
contentType: ContentType.json,
responseType: ResponseType.plain,
// connectTimeout: 5000,
// receiveTimeout: 100000,
headers: {
HttpHeaders.userAgentHeader: "dio",
"Connection": "keep-alive",
},
); //BaseOptions will be persisted throughout subsequent requests made with _dio
_dio.interceptors.add(
InterceptorsWrapper(
onResponse:(Response response) {
List<Cookie> cookies = persistentCookies.loadForRequest(Uri.parse(url));
csrfTokenValue = cookies.firstWhere((c) => c.name == 'csrftoken', orElse: () => null)?.value;
if (csrfTokenValue != null) {
_dio.options.headers['X-CSRF-TOKEN'] = csrfTokenValue; //setting the csrftoken from the response in the headers
}
print(response);
return response;
}
)
);
await _dio.get("https://www.xxxx.in/rest/user/login.json");
print(csrfTokenValue);
return csrfTokenValue;
} catch (error, stacktrace) {
print(error);
// print("Exception occured: $error stackTrace: $stacktrace");
return null;
}
}
SessionId() async {
try {
final csrf = await getCsrftoken();
FormData formData = new FormData.from({
"username": "${_loginData.username}",
"password": "${_loginData.password}",
"csrfmiddlewaretoken" : '$csrf'
});
Options optionData = new Options(
contentType: ContentType.parse("application/json"),
);
Response response = await _dio.post("https://www.xxxx.in/rest/user/login.json", data: formData, options: optionData);
print("StatusCode:${response.statusCode}");
// print(response.data);
if (response.statusCode == 200){
return Navigator.of(context).pushReplacement(MaterialPageRoute(
builder: (context) => HomeScreen(),
));
}
else{
throw Exception();
}
} on DioError catch(e) {
if(e.response != null) {
print( e.response.statusCode.toString() + " " + e.response.statusMessage);
print(e.response.data);
print(e.response.headers);
print(e.response.request);
} else{
print(e.request);
print(e.message);
}
}
catch (error, stacktrace) {
print("Exception occured: $error stackTrace: $stacktrace");
return null;
}
}
}
APIから応答コード200を取得した後、共有設定にエントリを作成できます。
SharedPreferences prefs = await SharedPreferences.getInstance();
prefs?.setBool("isLoggedIn", true);
次に、共有設定からステータスを確認した後、ユーザーをナビゲートできます
Future<void> main() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
var status = prefs.getBool('isLoggedIn') ?? false;
print(status);
runApp(MaterialApp(home: status == true ? Login() : Home()));
}
更新：-
それを行う別の方法は、スプラッシュ画面にロジックを追加することもでき、スプラッシュ画面はアプリのエントリポイントである必要があります
class SplashScreen extends StatefulWidget {
@override
State<StatefulWidget> createState() {
// TODO: implement createState
return _SplashScreenState();
}
}
class _SplashScreenState extends State<SplashScreen> {
@override
void initState() {
// TODO: implement initState
super.initState();
startTimer();
}
@override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
decoration: BoxDecoration(
image: DecorationImage(
image: AssetImage("assets/images/clinician_splash.png"),
fit: BoxFit.cover),
),
),
);
}
void startTimer() {
Timer(Duration(seconds: 3), () {
navigateUser(); //It will redirect after 3 seconds
});
}
void navigateUser() async{
SharedPreferences prefs = await SharedPreferences.getInstance();
var status = prefs.getBool('isLoggedIn') ?? false;
print(status);
if (status) {
Navigation.pushReplacement(context, "/Home");
} else {
Navigation.pushReplacement(context, "/Login");
}
}
}
ログアウトの場合、ログアウトボタンのonPressイベントに以下の機能を追加します。
void logoutUser(){
SharedPreferences prefs = await SharedPreferences.getInstance();
prefs?.clear()
Navigator.pushAndRemoveUntil(
context,
ModalRoute.withName("/SplashScreen"),
ModalRoute.withName("/Home")
);
}
ログイン認証情報については、iOSのKeyChainとAES Encryption for AndroidのラッパーであるFlutter Secure Storageを使用する必要があると思います。
https://pub.dev/packages/flutter_secure_storage#-readme-tab-