unregisterOfflineEvent method
注销 离线通知事件观察者
Implementation
void unregisterOfflineEvent(Observer<List<SignallingEvent>> observer) {
_unregisterObserver(observer, offlineEvent);
}
注销 离线通知事件观察者
void unregisterOfflineEvent(Observer<List<SignallingEvent>> observer) {
_unregisterObserver(observer, offlineEvent);
}