import 'dart:ffi'; import 'package:shared_preferences/shared_preferences.dart'; import 'CurrencyPair.dart'; const String CURRENCY_ONE = "conversion_one"; const String CURRENCY_TWO = "conversion_two"; class PreferenceProvider { late final SharedPreferences _prefs; Future init() async { _prefs = await SharedPreferences.getInstance(); } Future saveConversionPair(String s1, String s2) async { await _prefs.setString(CURRENCY_ONE, s1); await _prefs.setString(CURRENCY_TWO, s2); } CurrencyPair getConversionPair() { String? s1 = _prefs.getString(CURRENCY_ONE); String? s2 = _prefs.getString(CURRENCY_TWO); return CurrencyPair(s1, s2); } }