How to initialize SharedPreferences 2.0.15 in flutter? (Dart

I am using

shared_preferences: ^2.0.15

and save my values in local.

But when i change my screen and get my values app give me error be like this.

My question "How can i initialize SharedPreferences in best way?".

Video

  late SharedPreferences _preferences;

  @override
  void initState() {
    super.initState();
    getLocalData();
  }

  Future getLocalData() async {
    _preferences = await SharedPreferences.getInstance();
  }

CodePudding user response：

I've checked the video you shared.

You're just missing to call the getLocalData method inside the LoginViewModel.

I'd suggest adding a line inside your loginRequest method to call getLocalData method. Well, don't forget to await.

await getLocalData();

That's it :)

CodePudding user response：

actually you are not fetching data from your shared preference you have to get the data that u saved

first set data that you want to save

addStringToSF() async {
  SharedPreferences prefs = await SharedPreferences.getInstance();
  prefs.setString('email', "[email protected]");
}

then in your second screen you can get your data

  late SharedPreferences _preferences;
  late String email;  

  @override
  void initState() {
    super.initState();
    getLocalData();
  }

  Future getLocalData() async {
    _preferences = await SharedPreferences.getInstance();
    // for exemple you saved a string value with key ='email'
    email= _preferences.getString('email');
  }

check this : https://medium.flutterdevs.com/using-sharedpreferences-in-flutter-251755f07127