sendPresence method
Implementation
@override
void sendPresence(PresenceType presenceType, String myId) {
PresenceMessage presenceMessage = PresenceMessage(
id: const Uuid().v4(),
type: MessageType.presence,
presenceType: presenceType,
fromId: myId);
var payload = jsonEncode(presenceMessage.toJson());
clientHandler.sendPayload(payload, myId.toPresenceTopic);
}