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CHeaderCtrl::DrawItem

Called by the framework when a visual aspect of an owner-draw header control changes.

virtual void DrawItem(
   LPDRAWITEMSTRUCT lpDrawItemStruct 
);

Parameters

  • lpDrawItemStruct
    A pointer to a DRAWITEMSTRUCT structure describing the item to be painted.

Remarks

The itemAction member of the DRAWITEMSTRUCT structure defines the drawing action that is to be performed.

By default, this member function does nothing. Override this member function to implement drawing for an owner-draw CHeaderCtrl object.

The application should restore all graphics device interface (GDI) objects selected for the display context supplied in lpDrawItemStruct before this member function terminates.

Example

// NOTE: CMyHeaderCtrl is a class derived from CHeaderCtrl.
// The CMyHeaderCtrl object was created as follows:
//
//   CMyHeaderCtrl m_myHeader;
//   myHeader.Create(WS_CHILD | WS_VISIBLE | HDS_HORZ,
//      CRect(10, 10, 600, 50), pParentWnd, 1);

// This example implements the DrawItem method for a 
// CHeaderCtrl-derived class that draws every item as a
// 3D button using the text color red.
void CMyHeaderCtrl::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{
   // This code only works with header controls.
   ASSERT(lpDrawItemStruct->CtlType == ODT_HEADER);

   HDITEM hdi;
   const int c_cchBuffer = 256;
   TCHAR  lpBuffer[c_cchBuffer];

   hdi.mask = HDI_TEXT;
   hdi.pszText = lpBuffer;
   hdi.cchTextMax = c_cchBuffer;

   GetItem(lpDrawItemStruct->itemID, &hdi);

   // Draw the button frame.
   ::DrawFrameControl(lpDrawItemStruct->hDC, 
      &lpDrawItemStruct->rcItem, DFC_BUTTON, DFCS_BUTTONPUSH);

   // Draw the items text using the text color red.
   COLORREF crOldColor = ::SetTextColor(lpDrawItemStruct->hDC, 
      RGB(255,0,0));
   ::DrawText(lpDrawItemStruct->hDC, lpBuffer, 
      (int)_tcsnlen(lpBuffer, c_cchBuffer), 
      &lpDrawItemStruct->rcItem, DT_SINGLELINE|DT_VCENTER|DT_CENTER);
   ::SetTextColor(lpDrawItemStruct->hDC, crOldColor);
}

Requirements

Header: afxcmn.h

See Also

Reference

CHeaderCtrl Class

Hierarchy Chart

CWnd::OnDrawItem

Other Resources

CHeaderCtrl Members