Flutter SharedPreference do not persist

Question

I want to save user preferences using Flutter\'s SharedPreference. But the registered preferences are ALL null at new start (when app have been closed, not unis

Answer 1

import 'package:shared_preferences/shared_preferences.dart';
 
class MySharedPreferences {
  MySharedPreferences._privateConstructor();
 
  static final MySharedPreferences instance =
      MySharedPreferences._privateConstructor();
 
  setStringValue(String key, String value) async {
    SharedPreferences myPrefs = await SharedPreferences.getInstance();
    myPrefs.setString(key, value);
  }
 
  Future<String> getStringValue(String key) async {
    SharedPreferences myPrefs = await SharedPreferences.getInstance();
    return myPrefs.getString(key) ?? "";
  }
 
  Future<bool> containsKey(String key) async {
    SharedPreferences myPrefs = await SharedPreferences.getInstance();
    return myPrefs.containsKey(key);
  }
 
  removeValue(String key) async {
    SharedPreferences myPrefs = await SharedPreferences.getInstance();
    return myPrefs.remove(key);
  }
 
  removeAll() async{
    SharedPreferences myPrefs = await SharedPreferences.getInstance();
    return myPrefs.clear();
  }
 
}

For more reference: Flutter Shared Preferences Tutorial

Answer 2

Hi I also faced the same issue. Did so many things. nothing helped .This may help someone.First thing ,followed this url and did the changes

1.https://github.com/flutter/flutter/wiki/Upgrading-pre-1.12-Android-projects

2.Run the command flutter upgrade

3.Changed the shared preferences plugin in pubspec.yaml file

shared_preferences: ">=0.5.10 <2.0.0"

4.Deleted the pub cache from installed flutter location

C:\Users\myuser\AppData\Local\Pub\Cache\hosted\pub.dartlang.org

5.flutter build apk --debug

6.flutter build apk --profile

7.flutter run --release (if I run directly this command its throwing error like debug.jar not found , so I ran command 5 and 6 )

Command 7 is for - To Verify whether its working perfectly in release mode.

Finally I tried to generate app build without shrinking the code. then it worked

flutter build apk --no-shrink flutter build appbundle --no-shrink

Answer 3

I had the same issue and fixed it in Android/../MainActivity.java by adding at the top:

import io.flutter.plugins.GeneratedPluginRegistrant;

As well as under super.onCreate(savedInstanceState);

GeneratedPluginRegistrant.registerWith(this);

The problem comes from using

SharedPreferences.setMockInitialValues({}); 

I got it from Flutter Test MissingPluginException but it seems to clear all the shared preferences.

However if you remove SharedPreferences.setMockInitialValues({}); and you don't have the two lines above in MainActivity.java, you'll get:

MissingPluginException(No implementation found for method getAll on channel flutter: plugins.flutter.io/shared_preferences)

I hope it helps!