Hive boxes are deleted when app closes or restart - flutter

The problem is that Hive is acting unexpectedly, and when the app closes or I restart it all, the data in the box is cleared.
main.dart:
void main() async {
WidgetsFlutterBinding.ensureInitialized();
SystemChrome.setSystemUIOverlayStyle(
const SystemUiOverlayStyle(statusBarColor: Colors.transparent));
await Firebase.initializeApp();
await Hive.initFlutter();
Hive.registerAdapter(CredentialsModelAdapter());
Hive.registerAdapter(DoctorModelAdapter());
Hive.registerAdapter(DuserModelAdapter());
Hive.registerAdapter(DoctorAppointmentsAdapter());
Hive.registerAdapter(AppointmentStatusesAdapter());
Hive.registerAdapter(AccountTypeAdapter());
Hive.registerAdapter(UserAdapter());
await Hive.openBox<CredentialsModel>("cred");
await Hive.openBox<DuserModel>("doctor");
runApp(ProviderScope(child: MyApp()));
}
class MyApp extends StatelessWidget {
MyApp({Key? key}) : super(key: key);
final _appRouter = app_router.AppRouter();
#override
Widget build(BuildContext context) {
return MaterialApp.router(
title: "x",
debugShowCheckedModeBanner: false,
routerDelegate: _appRouter.delegate(),
routeInformationParser: _appRouter.defaultRouteParser(),
);
}
}
Here is where I fetch the data from the api and store it in box:
#override
Future<Either<ApiFailures, dynamic>> signInWithEmailAndPassword(
{required String email, required String password}) async {
late Box<CredentialsModel> credentials;
var result;
try {
final response = await http.get(Uri.parse(
"xxxxxxxx"));
if (response.statusCode == 200) {
result = await json.decode(response.body);
if (result["AZSVR"] == "FAILED") {
return const Left(ApiFailures.authFailed());
} else {
var content = CredentialsModel.fromJson(result);
credentials = Hive.box("cred");
credentials.put('cred', content);
return right(result["api_token"]);
}
}
} on SocketException catch (e) {
return const Left(ApiFailures.noConnection());
} on HttpException {
return const Left(ApiFailures.notfound());
} catch (_) {
return const Left(ApiFailures.notfound());
}
return Right(result["api_token"]);
}
Where I call the box:
import 'package:flutter/material.dart';
import 'package:flutter_hooks/flutter_hooks.dart';
import 'package:hive_flutter/hive_flutter.dart';
import 'package:hooks_riverpod/hooks_riverpod.dart';
import 'package:vwelfare/application/provider/doctor.repository.provider.dart';
import 'package:vwelfare/domain/models/doctor/duser.dart';
import '../../domain/models/credentials/credentials.dart';
class MyWidget extends HookConsumerWidget {
const MyWidget({super.key});
#override
Widget build(BuildContext context, WidgetRef ref) {
final Box<CredentialsModel> credBox = Hive.box("cred");
final Box<DuserModel> doctorBox = Hive.box("doctor");
final controller = useTextEditingController();
final uid = useState(0);
final cred = useState(const CredentialsModel());
return Scaffold(
body: ValueListenableBuilder(
valueListenable: credBox.listenable(),
builder: (context, Box<CredentialsModel> box, _) {
final cred = box.get("cred");
print(cred!.api_token);
final doctor = ref.watch(getDoctor(cred.api_token!));
return doctor.when(
data: (data) => data.fold(
(l) => ValueListenableBuilder(
valueListenable: doctorBox.listenable(),
builder: (context, Box<DuserModel> box, _) {
final model = box.get("doctor");
final doctor = model!.User;
if (doctor != null) {
return Center(
child: Text("${doctor.address}"),
);
} else {
return const Center(
child: Text("CONTACT US"),
);
}
}),
(r) => Center(child: Text("${r.User!.name}"))),
loading: () => const CircularProgressIndicator(),
error: (error, stackTrace) {
print(error);
return Center(
child: Text("$error hello"),
);
});
},
),
);
}
}
I don't know if I am doing something wrong but I followed the docs as they say:
1- registered the adapter
2- opened the box
3- called it in a widget
What am I doing wrong?

Related

flutter does not show data from API

When I try to pull data from the jsonplaceholder API and put it on the screen, I don't have any problems, but when I try to change the data in this link (https://reqres.in/api/users?page=2 ) on the reqres.io site with the same codes, only by changing the API and model, the text no data appears on the screen. I'm getting it can you help me ?
My project with JsonPlaceHolder
main.dart
import 'package:flutter/material.dart';
import 'package:my_app/models/json_model.dart';
import 'service/api_service.dart';
void main() =\> runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({super.key});
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Material App',
home: Scaffold(
appBar: AppBar(
title: const Text('Json Deneme'),
),
body: const Home(),
),
);
}
}
class Home extends StatefulWidget {
const Home({super.key});
#override
State\<Home\> createState() =\> \_HomeState();
}
class \_HomeState extends State\<Home\> {
List\<JsonModel\>? \_postItems;
bool \_isLoading = false;
String? \_errorMessage;
#override
void initState() {
super.initState();
loadData();
}
Future\<void\> loadData() async {
setState(() {
_isLoading = true;
_errorMessage = null;
});
try {
final postItems = await Api.fetchApi();
setState(() {
_postItems = postItems;
_isLoading = false;
});
} catch (e) {
setState(() {
_isLoading = false;
_errorMessage = 'Error fetching data: $e';
});
}
}
#override
Widget build(BuildContext context) {
if (\_isLoading) {
return const Center(child: CircularProgressIndicator());
} else if (\_postItems == null || \_postItems!.isEmpty) {
return const Center(child: Text('No Data'));
} else {
return ListView.builder(
itemCount: \_postItems!.length,
itemBuilder: (context, index) {
return ListTile(
title: Text(\_postItems!\[index\].name),
);
},
);
}
}
}`
api_service.dart
`import 'dart:io';
import 'package:my_app/models/json_model.dart';
import 'package:dio/dio.dart';
class Api {
static Future<List<JsonModel>?> fetchApi() async {
final res = await Dio().get("https://jsonplaceholder.typicode.com/users");
if (res.statusCode == HttpStatus.ok) {
final data = res.data!;
if (data is List) {
return data.map((e) =\> JsonModel.fromMap(e)).toList();
}
}
return <JsonModel>[];
}
}
`
conclusion
conclusion
My project with reqres.in
main.dart
`import 'package:flutter/material.dart';
import 'package:my_app/models/json_model.dart';
import 'service/api_service.dart';
void main() =\> runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({super.key});
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Material App',
home: Scaffold(
appBar: AppBar(
title: const Text('Json Deneme'),
),
body: const Home(),
),
);
}
}
class Home extends StatefulWidget {
const Home({super.key});
#override
State<Home> createState() => _HomeState();
}
class _HomeState extends State<Home> {
List<ReqresModel>? _postItems;
bool _isLoading = false;
String? _errorMessage;
#override
void initState() {
super.initState();
loadData();
}
Future<void> loadData() async {
setState(() {
_isLoading = true;
_errorMessage = null;
});
try {
final postItems = await Api.fetchApi();
setState(() {
_postItems = postItems;
_isLoading = false;
});
} catch (e) {
setState(() {
_isLoading = false;
_errorMessage = 'Error fetching data: $e';
});
}
}
#override
Widget build(BuildContext context) {
if (_isLoading) {
return const Center(child: CircularProgressIndicator());
} else if (_postItems == null || _postItems!.isEmpty) {
return const Center(child: Text('No Data'));
} else {
return ListView.builder(
itemCount: _postItems!.length,
itemBuilder: (context, index) {
return ListTile(
title: Text(\_postItems!\[index\].data\[index\].firstName),
);
},
);
}
}
}`
api_servise.dart
`import 'dart:io';
import 'package:my_app/models/json_model.dart';
import 'package:dio/dio.dart';
class Api {
static Future<List<ReqresModel>?> fetchApi() async {
final res = await Dio().get("https://reqres.in/api/users?page=2");
if (res.statusCode == HttpStatus.ok) {
final data = res.data!;
if (data is List) {
return data.map((e) => ReqresModel.fromMap(e)).toList();
}
}
return <ReqresModel>[];
}
}`
conclusion
conclusion
**Thank you **
I sent the API using Postman, there was no problem, I don't think the problem was caused by the API, sorry for my bad English
Change your api_service.dart for reqres.in project with following code.
First api which returns List directly, but second api which return Json which has data as List
Edited
main.dart
import 'package:flutter/material.dart';
import 'package:my_app/models/json_model.dart';
import 'service/api_service.dart';
void main() => runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({super.key});
#override
Widget build(BuildContext context) {
return MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Material App',
home: Scaffold(
appBar: AppBar(
title: const Text('Json Deneme'),
),
body: const Home(),
),
);
}
}
class Home extends StatefulWidget {
const Home({super.key});
#override
State<Home> createState() => _HomeState();
}
class _HomeState extends State<Home> {
List<ReqresModel>? _postItems;
bool _isLoading = false;
String? _errorMessage;
#override
void initState() {
super.initState();
loadData();
}
Future<void> loadData() async {
setState(() {
_isLoading = true;
_errorMessage = null;
});
try {
final postItems = await Api.fetchApi();
setState(() {
_postItems = postItems;
_isLoading = false;
});
} catch (e) {
setState(() {
_isLoading = false;
_errorMessage = 'Error fetching data: $e';
});
}
}
#override
Widget build(BuildContext context) {
if (_isLoading) {
return const Center(child: CircularProgressIndicator());
} else if (_postItems == null || _postItems!.isEmpty) {
return const Center(child: Text('No Data'));
} else {
return ListView.builder(
itemCount: _postItems!.length,
itemBuilder: (context, index) {
return ListTile(
title: Text(_postItems![index].firstName),//Updated here
);
},
);
}
}
}
api_service.dart
import 'dart:io';
import 'package:my_app/models/json_model.dart';
import 'package:dio/dio.dart';
class Api {
static Future<List<ReqresModel>?> fetchApi() async {
final res = await Dio().get("https://reqres.in/api/users?page=2");
if (res.statusCode == HttpStatus.ok) {
final data = res.data!['data'];//Updated here
if (data is List) {
return data.map((e) => ReqresModel.fromMap(e)).toList();
}
}
return <ReqresModel>[];
}
}
ReqresModel - should be updated
//Updated here
class ReqresModel {
int? id;
String? email;
String? firstName;
String? lastName;
String? avatar;
ReqresModel(
{this.id, this.email, this.firstName, this.lastName, this.avatar});
ReqresModel.fromJson(Map<String, dynamic> json) {
id = json['id'];
email = json['email'];
firstName = json['first_name'];
lastName = json['last_name'];
avatar = json['avatar'];
}
}

How to use MapShapeSource.network() with data from API Call (Post / Get from server)

I'm working with SfMaps syncfusion map and when I try to load geojson data from the local assets folder using the MapShapeSource.asset() property and everything works fine. But I'm having problems when I want to load geojson data as a result from api calling (GET / POST) using the http package flutter.
// Function to load data json from API
Future<void> loadGeojsonDataFromAPI() async {
setState(() => loading = true);
try {
final response = await http.post(
Uri.parse("some url"),
headers: {
'Content-Type': 'application/json; charset=UTF-8',
},
body: body);
if (response.statusCode >= 400) {
throw Exception('statusCode=${response.statusCode}');
}
setState(() {
loading = false;
data = jsonDecode(response.body);
});
} catch (e) {
setState(() => loading = false);
debugPrint("Error load data: $e");
return;
}
}
// Loadjson data from API in Map Shape Source.network() but not sure how to do it
dataSource = MapShapeSource.network(
'url',
shapeDataField: 'name',
);
I believe this can be solved using MapShapeSource.network(), but am still confused about how to use it.
any kind of help is very much appreciated
You can load the area shape JSON data from the web/network using the MapShapeSource.network() constructor available in the maps widget. We have shared the user guide documentation and sample below for your reference.
UG, https://help.syncfusion.com/flutter/maps/getting-started#from-network
Code snippet:
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:syncfusion_flutter_maps/maps.dart';
import 'package:http/http.dart' as http;
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({super.key});
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Syncfusion Flutter Maps',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: const MyHomePage(title: 'Syncfusion Flutter Maps'),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({super.key, required this.title});
final String title;
#override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
late MapShapeSource _dataSource;
late List<IndiaMap> _mapDetails;
Future<bool> _fetchNetworkJsonDetails() async {
if (_mapDetails.isNotEmpty) {
return true;
}
final http.Response response = await http
.get(Uri.tryParse('https://api.npoint.io/b127f79b6e9c883d0aba')!);
if (response.statusCode == 200) {
Map<String, dynamic> responseJson = json.decode(response.body);
List<dynamic> countriesCoordinates = responseJson['features'];
for (int i = 0; i < countriesCoordinates.length; i++) {
Map<String, dynamic> data = countriesCoordinates[i]['properties'];
IndiaMap mapDetail = IndiaMap.fromJsonMap(data);
_mapDetails.add(mapDetail);
}
_dataSource = MapShapeSource.network(
'https://api.npoint.io/b127f79b6e9c883d0aba',
shapeDataField: 'name',
dataCount: _mapDetails.length,
primaryValueMapper: (index) => _mapDetails[index].state,
);
return true;
} else {
throw Exception('Failed to load JSON');
}
}
#override
void initState() {
_mapDetails = [];
super.initState();
}
#override
void dispose() {
_mapDetails.clear();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text(widget.title)),
body: FutureBuilder(
future: _fetchNetworkJsonDetails(),
builder: (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
if (snapshot.hasData) {
return Padding(
padding: const EdgeInsets.all(15),
child: SfMaps(
layers: [
MapShapeLayer(
source: _dataSource,
color: const Color.fromRGBO(15, 59, 177, 0.5),
strokeColor: Colors.white,
strokeWidth: 0.5,
),
],
),
);
} else {
return const Center(child: CircularProgressIndicator());
}
}),
);
}
}
class IndiaMap {
late String state;
late String country;
IndiaMap(this.state, this.country);
IndiaMap.fromJsonMap(Map data) {
state = data['name'];
country = data['admin'];
}
}

Show a dialog instead of return a widget using Either in Flutter/Dart

I'm a little stuck and can't figure out how the architectural flow should work in this use case. I know almost nothing about functional programming, I'm using this Either from dartz package, a functional programming package. Can someone help me with the following:
I want to show a popup dialog instead of a widget if there is an error. But the design of Either seems to not allow this somehow as this if logic requires a widget of course. Is there a better design which I could accomplish this with?
Learning error handling here
import 'dart:convert';
import 'dart:io';
import 'package:dartz/dartz.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:awesome_dialog/awesome_dialog.dart';
void main() {
runApp(const MyApp());
}
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return ProviderScope(
child: MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.orange,
),
home: const HomePage(),
),
);
}
}
class HomePage extends StatelessWidget {
const HomePage({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
return Scaffold(
backgroundColor: Colors.blueGrey,
body: Flex(
direction: Axis.horizontal,
children: [
Expanded(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: CrossAxisAlignment.center,
children: [
Consumer(
builder: (ctx, ref, child) {
if (ref.watch(notifier).state == NotifierState.initial) {
return const Text('Press the button');
} else if (ref.watch(notifier).state == NotifierState.loading) {
return const CircularProgressIndicator();
} else {
return ref.read(notifier).post.fold(
(failure) {
showDialog( /// Error here, expects a widget
context: context,
barrierDismissible: true,
builder: (BuildContext context) => AlertDialog(
title: Text(failure.toString()),
),
);
},
(post) => Text(post.toString()),
);
}
},
),
Consumer(
builder: (ctx, ref, child) {
return ElevatedButton(
onPressed: () {
ref.read(notifier).getOnePost();
},
child: const Text('Get Post'));
},
),
],
),
),
],
),
);
}
}
class PostService {
final httpClient = FakeHttpClient();
Future<Post?> getOnePost() async {
try {
final responseBody = await httpClient.getResponseBody();
return Post.fromJson(responseBody);
} on SocketException {
throw Failure('No Internet connection 😑');
} on HttpException {
throw Failure("Couldn't find the post 😱");
} on FormatException {
throw Failure("Bad response format 👎");
}
}
}
class FakeHttpClient {
Future<String> getResponseBody() async {
await Future.delayed(const Duration(milliseconds: 500));
//! No Internet Connection
// throw SocketException('No Internet');
//! 404
throw HttpException('404');
//! Invalid JSON (throws FormatException)
// return 'abcd';
// return '{"userId":1,"id":1,"title":"nice title","body":"cool body"}';
}
}
enum NotifierState { initial, loading, loaded }
final notifier = ChangeNotifierProvider((ref) => PostChangeNotifier());
class PostChangeNotifier extends ChangeNotifier {
final _postService = PostService();
NotifierState _state = NotifierState.initial;
NotifierState get state => _state;
void _setState(NotifierState state) {
_state = state;
notifyListeners();
}
late Either<Failure, Post?> _post;
Either<Failure, Post?> get post => _post;
// Set post
void _setPost(Either<Failure, Post?> post) {
_post = post;
notifyListeners();
}
// Set one post
void getOnePost() async {
_setState(NotifierState.loading);
await Task(() => _postService.getOnePost())
.attempt()
.mapLeftToFailure()
.run()
.then((value) => _setPost(value as Either<Failure, Post?>));
_setState(NotifierState.loaded);
}
}
extension TaskX<T extends Either<Object, U>, U> on Task<T> {
Task<Either<Failure, U>> mapLeftToFailure() {
return map(
(either) => either.leftMap((obj) {
try {
return obj as Failure;
} catch (e) {
throw obj;
}
}),
);
}
}
class Post {
final int id;
final int userId;
final String title;
final String body;
Post({
required this.id,
required this.userId,
required this.title,
required this.body,
});
static Post? fromMap(Map<String, dynamic> map) {
return Post(
id: map['id'],
userId: map['userId'],
title: map['title'],
body: map['body'],
);
}
static Post? fromJson(String source) => fromMap(json.decode(source));
#override
String toString() {
return 'Post id: $id, userId: $userId, title: $title, body: $body';
}
}
class Failure {
// Use something like "int code;" if you want to translate error messages
final String message;
Failure(this.message);
#override
String toString() => message;
}
you don't call a function instead of widget, You should call class and initialize your dialog in initState
// call show dialog
(failure) {
ShowDialogScreen(failure: failure.toString());
},
// show dialog screen
class ShowDialogScreen extends StatefulWidget {
final String failure;
const ShowDialogScreen({Key key, this.failure}) : super(key: key);
#override
_ShowDialogScreenState createState() => _ShowDialogScreenState();
}
class _ShowDialogScreenState extends State<ShowDialogScreen> {
#override
void initState() {
super.initState();
WidgetsBinding.instance.addPostFrameCallback((_) async {
await showDialog(
context: context,
barrierDismissible: true,
builder: (BuildContext context) => AlertDialog(
title: Text(widget.failure),
),
);
});
}
#override
Widget build(BuildContext context) {
return Container();
}
}

Flutter PhpMyAdmin Fetch Data

I wanna fetch data from PhpMyAdmin. But i am facing one issue. I can see in the body my data. I am sharing my source code. Thx for helping. And I am working with flutter desktop.
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
class WarehousePage extends StatefulWidget {
const WarehousePage({Key key}) : super(key: key);
#override
_WarehousePageState createState() => _WarehousePageState();
}
class _WarehousePageState extends State<WarehousePage> {
List data = [];
#override
void initState() {
fetchData();
super.initState();
}
void fetchData() async {
final response =
await http.get(Uri.parse('url/getdata.php'));
data = json.decode(response.body);
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: ListView.builder(
itemCount: data.length,
itemBuilder: (BuildContext context, int index) => ListTile(
title: Text(data[index]['productName']),
),
),
);
}
}
Update my code but still same. What is wrong? I have not any model class. I am see my data in the body and debug console. But i cant write it in the listview.
import 'dart:convert';
import 'dart:io';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
class WarehousePage extends StatefulWidget {
const WarehousePage({Key key}) : super(key: key);
#override
_WarehousePageState createState() => _WarehousePageState();
}
class _WarehousePageState extends State<WarehousePage> {
List data = [];
#override
void initState() {
fetchData();
super.initState();
}
Future<List> fetchData() async {
var jsonResponse;
try {
var url = Uri.parse('https://rul/getdata.php');
var response = await http.get(url).timeout(const Duration(seconds: 20));
if (response.statusCode == 200) {
jsonResponse = json.decode(response.body);
if (jsonResponse != null) {
return (json.decode(response.body) as List)
.map((data) => (data))
.toList();
}
}
} on SocketException catch (e) {
print(e);
} catch (e) {
print(e);
}
return jsonResponse;
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: ListView.builder(
itemCount: data.length,
itemBuilder: (BuildContext context, int index) => ListTile(
title: Text(data[index]['productName']),
),
),
);
}
}
static Future<List<SomeModel>> fetchQuizTest() async {
var jsonResponse;
try {
var url = Uri.parse(url');
var response = await http.get(url).timeout(const Duration(seconds: 20));
if (response.statusCode == 200) {
jsonResponse = json.decode(response.body);
if (jsonResponse != null) {
return (json.decode(response.body) as List)
.map((data) => new SomeModel.fromJson(data))
.toList();
}
}
} on SocketException catch (e) {
print(e);
} catch (e) {
print(e);
}
return jsonResponse;
}

How to read file from file to flutter?

I have code that I use to write data to a file (such as global settings for an application). I write down the data and see. But the problem is that I do not understand how to take these mini data from another page. For example I wrote the word "Test" and I want and I want to assign that word to some variable in another page. I will be grateful for your help. Here is my code:
import 'dart:io';
import 'dart:async';
import 'package:path_provider/path_provider.dart';
import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart';
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: "Reading and Writing to Storage",
home: Home(
storage: Storage(),
),
);
}
}
class Home extends StatefulWidget {
final Storage storage;
Home({Key key, #required this.storage}) : super(key: key);
#override
HomeState createState() => HomeState();
}
class HomeState extends State<Home> {
TextEditingController controller = TextEditingController();
String state;
Future<Directory> _appDocDir;
#override
void initState() {
super.initState();
widget.storage.readData().then((String value) {
setState(() {
state = value;
});
});
}
Future<File> writeData() async {
setState(() {
state = controller.text;
controller.text = '';
});
return widget.storage.writeData(state);
}
void getAppDirectory() {
setState(() {
_appDocDir = getApplicationDocumentsDirectory();
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Reading and Writing Files'),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.spaceEvenly,
children: <Widget>[
Text('${state ?? "File is Empty"}'),
TextField(
controller: controller,
),
RaisedButton(
onPressed: writeData,
child: Text('Write to File'),
),
RaisedButton(
child: Text("Get DIR path"),
onPressed: getAppDirectory,
),
FutureBuilder<Directory>(
future: _appDocDir,
builder:
(BuildContext context, AsyncSnapshot<Directory> snapshot) {
Text text = Text('');
if (snapshot.connectionState == ConnectionState.done) {
if (snapshot.hasError) {
text = Text('Error: ${snapshot.error}');
} else if (snapshot.hasData) {
text = Text('Path: ${snapshot.data.path}');
} else {
text = Text('Unavailable');
}
}
return new Container(
child: text,
);
},
)
],
),
),
);
}
}
class Storage {
Future<String> get localPath async {
final dir = await getApplicationDocumentsDirectory();
return dir.path;
}
Future<File> get localFile async {
final path = await localPath;
return File('$path/db.txt');
}
Future<String> readData() async {
try {
final file = await localFile;
String body = await file.readAsString();
return body;
} catch (e) {
return e.toString();
}
}
Future<File> writeData(String data) async {
final file = await localFile;
return file.writeAsString("$data");
}
}
And scrin:
You can pass the value to other page using Navigator and parameter.
class NewScreen extends StatelessWidget {
final String data;
NewScreen({this.data});
...
}
When you move to 'NewScreen' by using Navigator at your 'Home' page,
pass the data what you transfer.
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => NewScreen(data: 'Test'),
),
);