C / C++ / MFC

// This code fails on VS.NET 2003 (VC++) with a error.
//
// error C2511: 'MyBase2 *MyDerived::Copy(void)' :
// overloaded member function not found in 'MyDerived'
//
// Removing the 'const' qualifiers fixes the problem.

class MyBase
{
public:
   MyBase()  {}
   virtual ~MyBase()  {}

   virtual MyBase *Copy() const
   {
     return new MyBase(*this);
   }
};

class MyBase2
{
public:
   MyBase2()  {}
   virtual ~MyBase2()  {}

   virtual MyBase2 *Copy() const
   {
     return new MyBase2(*this);
   }
};

class MyDerived : public MyBase, public MyBase2
{
public:
   MyDerived()  {}
   virtual ~MyDerived()  {}

   virtual MyDerived *Copy() const
   {
     return new MyDerived(*this);
   }
};

int main()
{
  return 0;
}

<br />
void CApmDlg::OnCustomdrawMyList ( NMHDR* pNMHDR, LRESULT* pResult )<br />
{<br />
   NMLVCUSTOMDRAW* pLVCD = reinterpret_cast<NMLVCUSTOMDRAW*>( pNMHDR );<br />
<br />
   // Take the default processing unless we set this to something else below.<br />
   *pResult = CDRF_DODEFAULT;<br />
<br />
   // First thing - check the draw stage. If it's the control's prepaint<br />
   // stage, then tell Windows we want messages for every item.<br />
<br />
   if ( CDDS_PREPAINT == pLVCD->nmcd.dwDrawStage ) {<br />
      *pResult = CDRF_NOTIFYITEMDRAW;<br />
      }<br />
   else if ( CDDS_ITEMPREPAINT == pLVCD->nmcd.dwDrawStage ) {<br />
<br />
      //Get current Item's data<br />
      MAnciProcedure* pData = (MAnciProcedure*)m_historyLC.GetItemData(pLVCD->nmcd.dwItemSpec);<br />
<br />
      //If data is also in tree control change color<br />
      HTREEITEM hItem = m_pushTree.GetFirstVisibleItem();<br />
      while ( hItem ) {<br />
         if ( *pData == *(MAnciProcedure*)m_pushTree.GetItemData(hItem) ) {<br />
            COLORREF crBkgnd;<br />
            crBkgnd = RGB(192,192,192);<br />
            pLVCD->clrTextBk = crBkgnd;<br />
            }<br />
         //Get next Item<br />
         if ( m_pushTree.ItemHasChildren(hItem) ) {<br />
            hItem = m_pushTree.GetChildItem(hItem);<br />
            }<br />
         else if ( m_pushTree.GetNextItem(hItem, TVGN_NEXT) ) {<br />
               hItem = m_pushTree.GetNextItem(hItem, TVGN_NEXT);<br />
               }<br />
         else {<br />
            hItem = m_pushTree.GetParentItem(hItem);<br />
            if ( hItem ) {<br />
               hItem = m_pushTree.GetNextItem(hItem, TVGN_NEXT);<br />
               }<br />
            }<br />
         }  <br />
<br />
      // Tell Windows to paint the control itself.<br />
      *pResult = CDRF_DODEFAULT;<br />
   }<br />
}<br />