Flutter - How to get value from shared preferences in a non-async method

Question

I am trying to get some values saved in the SharedPreferences from a getter method of a class. But SharedPreferences.getInstance() returns a Futu

Answer 1

You can use FutureBuilder()

SharedPreferences sharedPrefs;

@override
Widget build(BuildContext context) {
  return FutureBuilder(
    future: _getPrefs(),
    builder: (context, snapshot) {
      if (snapshot.hasData) {
        return YourFinalWidget();
      }
      return CircularProgressIndicator(); // or some other widget
    },
  );
}

Future<void> _getPrefs() async{
  sharedPrefs = await SharedPreferences.getInstance();
}

Answer 2

You can do it in initState() and after this call setState() to update your build() method. Other way is to use FutureBuilder()

SharedPreferences sharedPrefs;

@override
void initState() {
  super.initState();
  SharedPreferences.getInstance().then((prefs) {
    setState(() => sharedPrefs = prefs);
  });
}