private void OpenLobby(object parameter) { Guid lobbyId = (Guid)parameter; Lobby lobbyToOpen = _lobbyProxy.GetLobbyById(lobbyId); CustomPrincipal customPrincipal = Thread.CurrentPrincipal as CustomPrincipal; Guid userId = customPrincipal.Identity.Id; Account account = _accountProxy.FindById(userId); //TODO: Check if private and do whatever from there if (ContainsAccount(userId, lobbyId)) { LobbyWindow _lobbyWindow = new LobbyWindow(lobbyToOpen, _dashboardWindow); _lobbyWindow.Show(); Lobbies = _lobbyProxy.GetLobbies(); } else { MessageBox.Show("You already joined a lobby", "Error", MessageBoxButton.OK, MessageBoxImage.Error); } }