readValue method
Implementation
Future<String?> readValue(String key) async {
try {
final items = await reader.getValues();
final index = items.indexWhere((element) => element.name == key);
if (index == -1) return null;
final enabled = items[index].state ?? false;
if (!enabled) return null;
return items[index].value;
} catch (err) {
throw Exception("La lectura de la variable $key fallo");
}
}