unsubscribe method Null safety
stop receiving messages for this channel
Implementation
void unsubscribe() {
final callback = onUnsubscribed;
final unsubscribeParameters = {'identifier': identifier, 'command': 'unsubscribe'};
state = HotlineSubscriptionRequestState.unsubscribed;
subscriptionManager.connection.socketChannel.sink.add(unsubscribeParameters);
/// ask the subscriptionManager to unsubscribe so that everything is cleaned up properly
if(!_cancelledBySubscriptionManager) {
subscriptionManager.unsubscribe(this);
}else if(callback != null) {
callback();
}
}