writeTo method
Writes the variable header to the supplied stream.
Implementation
@override
void writeTo(MqttByteBuffer variableHeaderStream) {
writeTopicName(variableHeaderStream);
if (header!.qos == MqttQos.atLeastOnce ||
header!.qos == MqttQos.exactlyOnce) {
writeMessageIdentifier(variableHeaderStream);
}
}