subscribed method

Subscription? subscribed({ required String topic, MqttQos qos = MqttQos.atMostOnce, })

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Implementation

Subscription? subscribed(
    {required String topic, MqttQos qos = MqttQos.atMostOnce}) {
  if (mqttClient == null) return null;
  return mqttClient?.subscribe(topic, qos);
}