subscribe method

Subscription? subscribe(
  1. String topic,
  2. MqttQos qosLevel
)

Initiates a topic subscription request to the connected broker with a strongly typed data processor callback. The topic to subscribe to. The qos level the message was published at. Returns the subscription or null on failure

Implementation

Subscription? subscribe(String topic, MqttQos qosLevel) {
  if (connectionStatus!.state != MqttConnectionState.connected) {
    throw ConnectionException(connectionHandler?.connectionStatus.state);
  }
  return subscriptionsManager!.registerSubscription(topic, qosLevel);
}