private void ButtonGroupConfig_Click(object sender, RoutedEventArgs e) { wndAgentsGroupConfig wagc; if ((service as StopService).PassengersGroup == null) { wagc = new wndAgentsGroupConfig(); } else { wagc = new wndAgentsGroupConfig((service as StopService).PassengersGroup); } if (wagc.ShowDialog() == true) { AgentsGroup group = wagc.GetGroup(); group.IsServiceGroup = true; if (group.ID == -1) { group.ID = GroupIDEnumerator.GetNextID(); } (service as StopService).PassengersGroup = group; } }