// the derived class must implement this function to actually draw the item
// with the given index on the provided DC
virtual void OnDrawItem(wxDC& dc, const wxRect& rect, size_t n) const = 0;
// the derived class must implement this function to actually draw the item
// with the given index on the provided DC
virtual void OnDrawItem(wxDC& dc, const wxRect& rect, size_t n) const = 0;