flutter_secure_storage: ^4.2.0

kita akan pake flutter_secure_storage: ^4.2.0

ubah minSdkVersion jadi 20 di path android/app/build.gradle

minSdkVersion 20

buat file 

import 'package:flutter_secure_storage/flutter_secure_storage.dart';

class SecureStorage {

  final _storage = FlutterSecureStorage();

  Future writeSecureData(String key, String value) async {

    var data = await _storage.write(key: key, value: value);

    return data;

  }

  Future readSecureData(String key) async {

    var data = await _storage.read(key: key);

    return data;

  }

  Future deleteSecureData(String key) async {

    var data = await _storage.delete(key: key);

    return data;

  }

}

cara gunainnya

import 'package:auth/local_storage.dart'; 

Future hasToken() async {

final SecureStorage secureStorage = SecureStorage();

final String? token = await secureStorage.readSecureData("token");

if (token != null) return token;

return null;

}

Future setLocalToken(String token) async { 

final SecureStorage secureStorage = SecureStorage();

await secureStorage.writeSecureData("token", token);

}

Future unsetLocalToken() async {

final SecureStorage secureStorage = SecureStorage();

secureStorage.deleteSecureData("token");

}