private void bOk_Click(object sender, RoutedEventArgs e)
        {
            try
            {
                if (tbname.Text == "" || tbvolume.Text == "" || tbprice.Text == "")
                {
                    MessageBox.Show("Заполните форму", "", MessageBoxButton.OK, MessageBoxImage.Information);
                }

                else if (!flag)
                {
                    IGroupService groupService = new GroupServise("DbConnection");

                    groupService.AddCoffeToGroup(GID, WindowToModel());
                    Close();
                }
                else
                {
                    ICoffeService  coffeService = new CoffeService("DbConnection");
                    CoffeViewModel coffe        = WindowToModel();
                    coffe.CoffeId = CID;
                    coffe.groupId = GID;
                    // coffeService.CreateCoffe(coffe);
                    coffeService.UpdateCoffe(coffe);
                    Close();
                }
            }
            catch
            {
                MessageBox.Show("Введены некорректные данные!!!");
            }
        }
        private void bOk_Click(object sender, RoutedEventArgs e)
        {
            if (tbname.Text == "")
            {
                MessageBox.Show("Заполните форму", "", MessageBoxButton.OK, MessageBoxImage.Information);
            }
            else if (!flag)
            {
                IGroupService groupService = new GroupServise("DbConnection");
                groupService.CreateGroup(WindowToModel());
                Close();
            }
            else
            {
                IGroupService  groupService = new GroupServise("DbConnection");
                GroupViewModel groupVM      = WindowToModel();

                groupVM.GroupId = GID;
                // groupVM.Coffes = coffes;
                groupService.UpdateGroup(groupVM);

                Close();
            }
        }