Can i store a Map<String, Object> inside a Shared Preferences in dart?

Question

Is there a way that we could save a map object into shared preferences so that we can fetch the data from shared preferences rather than listening to the database all the time. actually i want to reduce the amount of data downloaded from firebase. so i am thinking of a solution to have a listener for shared prefs and read the data from shared prefs.

But i dont see a way of achieving this in flutter or dart.

Please can someone help me to achieve this if there is a workaround.

Many Thanks, Mahi

Answer 1

If you convert it to a string, you can store it

import 'dart:convert'; ... var s = json.encode(myMap); // or var s = jsonEncode(myMap); 

json.decode(...)/jsonDecode(...) makes a map from a string when you load it.

Answer 2

Might be easier with this package: https://pub.dartlang.org/packages/pref_dessert

Look at the example:

import 'package:pref_dessert/pref_dessert.dart';  /// Person class that you want to serialize: class Person {   String name;   int age;    Person(this.name, this.age); }  /// PersonDesSer which extends DesSer<T> and implements two methods which serialize this objects using CSV format: class PersonDesSer extends DesSer<Person>{   @override   Person deserialize(String s) {     var split = s.split(",");     return new Person(split[0], int.parse(split[1]));   }    @override   String serialize(Person t) {     return "${t.name},${t.age}";   }  }  void main() {   var repo = new FuturePreferencesRepository<Person>(new PersonDesSer());   repo.save(new Person("Foo", 42));   repo.save(new Person("Bar", 1));   var list = repo.findAll();  } 

Package is still under development so it might change, but any improvements and ideas are welcomed! :)