Fix resizing problem in above article


Override CListCtrl::OnNotify as follows :

BOOL CMyListCtrl::OnNotify(WPARAM wParam, LPARAM lParam, LRESULT*pResult) 
{
  HD_NOTIFY *pHD = (HD_NOTIFY*)lParam;

  if ((pHD->hdr.code == HDN_ITEMCHANGINGA || pHD->hdr.code == HDN_ITEMCHANGINGW) && (GetStyle() & LVS_TYPEMASK) == LVS_REPORT)
  { // Invalidate empty bottom part of control to force erase the previous position of column
    int nBottom,nLastItem=GetItemCount()-1;
    if (nLastItem<0)
      nBottom=0; // List is empty : invalidate whole client rect
    else
    { // Get Y position of bottom of list (last item)
      RECT ItemRect;
      GetItemRect(nLastItem,&ItemRect,LVIR_BOUNDS);
      nBottom=ItemRect.bottom;
    }
    
    RECT rect;
    GetClientRect(&rect);
    if (nBottom<rect.bottom)
    { // Set top of rect as bottom of list (last item) : rect = empty part of list
      rect.top=nBottom;
      InvalidateRect(&rect);
    }

    // NB: We must to on with default processing.
  }

  *pResult = 0;
  return CListCtrl::OnNotify(wParam, lParam, pResult);
}

Simply adding a HDN_ITEMCHANGING or HDN_TRACK handler with
ClassWizarddoesn't work. These handlers are not called. Why ???
I noticed that class wizard places an ON_NOTIFY_REFLECT(...) entry for
these notifications. I'd rather put an ON_NOTIFY(...) since the
notification comes from the header control to its parent (the listctrl).
But Spy++ shows that the CtrlID of the header is 0. repplacing the
ON_NOTIFY_REFLECT entry by ON_NOTIFY(HDN_xxx,0,f) didn't solve the
problem. That's why I chose to override OnNotify()



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