A firedart TokenStore that uses Android and iOS preferences as persistence mechanism

preferences_store.dart

import 'dart:convert';

import 'package:firedart/firedart.dart';
import 'package:shared_preferences/shared_preferences.dart';

/// Stores tokens as preferences in Android and iOS.
/// Depends on the shared_preferences plugin: https://pub.dev/packages/shared_preferences
class PreferencesStore extends TokenStore {
  static const keyToken = "auth_token";

  static Future<PreferencesStore> create() async =>
      PreferencesStore._internal(await SharedPreferences.getInstance());

  SharedPreferences _prefs;

  PreferencesStore._internal(this._prefs);

  @override
  Token read() => _prefs.containsKey(keyToken)
      ? Token.fromMap(json.decode(_prefs.get(keyToken)))
      : null;

  @override
  void write(Token token) =>
      _prefs.setString(keyToken, json.encode(token.toMap()));

  @override
  void delete() => _prefs.remove(keyToken);
}

This won't work anymore due to null safety.

Use these two overrides instead:

@override Token? read() => _prefs.containsKey(keyToken) ? Token.fromMap(json.decode(_prefs.get(keyToken) as String)) : null;

@override void write(Token? token) => token != null ? _prefs.setString(keyToken, json.encode(token.toMap())) : null;

When I call FirebaseAuth.initialize(apiKey, PreferencesStore());, I get this error message
The class 'PreferencesStore' doesn't have a default constructor.
@fleeser @cachapa

@peterBrxwn do it like this

  var firebaseAuth = FirebaseAuth.initialize(apiKey, await PreferencesStore.create());