decrypt method
Implementation
@override
Future<String?> decrypt({
required String tag,
required String message,
required String sharedPreferences,
}) async {
var iv = await getIV(key: tag, sharedPreferences: sharedPreferences);
log('iv sp : $iv');
final res = await methodChannel.invokeMethod<String?>(
'decrypt',
{'tag': tag, 'message': message, 'iv': iv},
);
if (res == null) return null;
var jsonRes = json.decode(res);
return jsonRes['plainText'];
}