C / C++ / MFC

ragavan wrote:

Can anyone tell me why it is necessary to overload new and delete operator

Cedric Moonen wrote:

It is certainly not necessary to overload these operators. It can be done, sure, but it is never needed. I never did that myself (and I don't see a reason why I would do so).

Cedric Moonen wrote:

An example of what you can do by overloading these operators is what MFC does: it allows to track memory leaks.

James R. Twine wrote:

Yikes! Please be careful saying things like this to less-experienced developers - just because you never had a reason to do so does not mean that one does not exist.

ragavan wrote:

why it is necessary to overload new and delete operator

study.sourabh wrote:

how can i get the cell which user selected?

int CXListCtrl::GetCurSel()
{
	POSITION pos = GetFirstSelectedItemPosition();
	int nSelectedItem = -1;
	if (pos != NULL)
		nSelectedItem = GetNextSelectedItem(pos);
	return nSelectedItem;
}

study.sourabh wrote:

Is it posible to change the icone used for check box ?

void CXListCtrlTestDlg::OnClick(NMHDR* pNMHDR, LRESULT* pResult)
{
	LPNMITEMACTIVATE pNMIA = reinterpret_cast<LPNMITEMACTIVATE>(pNMHDR);
	int nItem = -1;
	int nSubItem = -1;
	if (pNMIA)
	{
		nItem = pNMIA->iItem;
		nSubItem = pNMIA->iSubItem;
	}

	if (nItem >= 0 && nSubItem >= 0)
	{
		CString strText = m_List.GetItemText(nItem, nSubItem);
		Log(_T("OnClick at (%d,%d):  '%s'"), nItem, nSubItem, strText);
	}

	*pResult = 0;
}

<br />
BOOL IsSum(const CUIntArray& Array,UINT Sum) const<br />
{<br />
	for(int i=0;i < Array.GetSize();i++)<br />
	{<br />
		if(Array[i] == Sum)<br />
			return TRUE;<br />
		else if(Array[i] < Sum)<br />
		{<br />
			if(CheckSum(Array,Sum,i,Array[i]))<br />
				return TRUE;<br />
		}<br />
	}<br />
	return FALSE;<br />
}<br />
<br />
BOOL CheckSum(const CUIntArray& Array,UINT Sum,int nIndex,UINT SoFar) const<br />
{<br />
  for(int i=nIndex+1;i < Array.GetSize();i++)<br />
 {<br />
   if((SoFar+Array[i]) == Sum)<br />
     return TRUE;<br />
   else if((SoFar+Array[i])<Sum)<br />
   {<br />
      if(CheckSum(Array,Sum,i,SoFar+Array[i]))<br />
         return TRUE;<br />
   }<br />
 }	<br />
 return FALSE;<br />
}<br />

SCROLLBARINFO info;
GetScrollBarInfo(OBJID_VSCROLL,&info);
if (info.rgstate[0] & STATE_SYSTEM_OFFSCREEN)
{
  //vertical scroll bar is present for window, but is not displayed
}

SNI wrote:

I am looking this in VC++.