Get value from SharedPreferences without future builder - flutter

Question

I need to get one stored value from shared preferences and put it into text widget. How can I do this without a future builder?
_currPage() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
int page = prefs.getInt('currPage') ?? 0;
return page;
}
class _AllTasksPageState extends State<AllTasksPage> {
#override
Widget build(BuildContext context) {
...
Text(_currPage()); //not working
...
}
}

Answer 1

int page = 0;
#override
void initState() {
super.initState();
readData();
}
#override
Widget build(BuildContext context) {
return Scaffold(
body: Center(
child: Text('$page'),
),
);
}
void readData() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
if (prefs.getInt('currPage') == null)
setState(() => page = 0);
else
setState(() => page = prefs.getInt('currPage')!);
}

Answer 2

create a helper class just for shared preferences
import 'package:shared_preferences/shared_preferences.dart';
class SPHelper {
SPHelper._();
static SPHelper sp = SPHelper._();
SharedPreferences? prefs;
Future<void> initSharedPreferences() async {
prefs = await SharedPreferences.getInstance();
}
Future<void> save(String name, String value) async {
await prefs!.setString(name, value);
}
String? get(String key) {
return prefs!.getString(key);
}
Future<bool> delete(String key) async {
return await prefs!.remove(key);
}
}
in your main function add
Future<void> main() async {
WidgetsFlutterBinding.ensureInitialized();
await SPHelper.sp.initSharedPreferences();
...
runApp(MyApp());
...
}
then to get your data just write
SPHelper.sp.get("YOUR_KEY")
and to store your data just write
SPHelper.sp.save("YOUR_KEY","YOUR_VALUE")
This is the best way to use shared preference.
I hope that's will help you in your problem.

Answer 3

The simplest method is using a SharedPreferences provider:
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';
import 'package:shared_preferences/shared_preferences.dart';
void main() async {
WidgetsFlutterBinding.ensureInitialized();
runApp(
MultiProvider(
providers: [
Provider.value(value: await SharedPreferences.getInstance()),
],
child: MaterialApp(
home: AllTasksPage(),
),
),
);
}
class AllTasksPage extends StatelessWidget {
const AllTasksPage({Key? key}) : super(key: key);
#override
Widget build(BuildContext context) {
final page = context.read<SharedPreferences>().getInt('currPage') ?? 0;
return Scaffold(body: Text('$page'));
}
}

Answer 4

If you don't want to use a future builder, the other solution is if you have a variable that tells you that are you still waiting/loading data and if yes, show a waiting screen:
class _AllTasksPageState extends State<AllTasksPage> {
bool _loading = true;
String? textValue; // String textValue = "";
#override
initState() {
super.initState();
setTextValue();
}
setTextValue() {
SharedPreferences prefs = await SharedPreferences.getInstance();
int page = prefs.getInt('currPage') ?? 0;
setState(() {
textValue = "$page";
_loading = false;
});
}
// then in the build method
#override
Widget build(BuildContext context) {
return _loading ? CircularProgressIndicator() : actualScreen();
}
}