public void OpenNewBookDetail()
        {
            var item = _bookDetailCreator();

            item.Title = "Book " + _newItemCounter++;
            Details.Add(item);
            SelectedDetail = item;
        }
 private void CloseDetail(DetailViewModelBase item)
 {
     Details.Remove(item);
     if (item == SelectedDetail)
     {
         SelectedDetail = null;
     }
 }
        public void OpenNewFriendDetail()
        {
            var item = _friendDetailCreator();

            item.FirstName  = "Thomas";
            item.LastName   = "Huber " + _newItemCounter++;
            item.HasChanges = false;
            Details.Add(item);
            SelectedDetail = item;
        }
 private void SelectDetail(DetailViewModelBase item)
 {
     SelectedDetail = item;
 }