public void Process(HideNotification message)
 {
     if (notifications.ContainsKey(message.NotificationId))
     {
         var notificationViewModelToHide = notifications[message.NotificationId];
         CurrentVisibleNotifications.Remove(notificationViewModelToHide);
     }
 }
        public void Process(ShowNotification message)
        {
            var notificationId        = Guid.NewGuid();
            var notificationViewModel = new NotificationViewModel(message.NotificationMessage,
                                                                  notificationId,
                                                                  viewModelCommunication);

            if (message.SecondsToShow > 0)
            {
                Application.Current.Dispatcher.DelayInvoke(
                    () => viewModelCommunication.Send(new HideNotification(notificationId)),
                    TimeSpan.FromSeconds(message.SecondsToShow)
                    );
            }

            notifications.Add(notificationId, notificationViewModel);
            CurrentVisibleNotifications.Add(notificationViewModel);
        }