Fix resizing problem in above article

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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()