How to adjust width of a column to the width of the longest string in CListCtrl?

Question

I am trying:

tstring subItemText;
    CDC* pDc = GetListCtrl().GetDC(); 
    for (int row = GetItemCount() - 1; row >= 0; --row) 
    {
      subItemText = _T("");
      for (int col = 0; col < NumCol; ++col)  
      {
        subItemText = this->GetSubItemString( GetItemData(row), col);
        CSize sz; 
        // get length of the string in logical units, by default 1 unit == 1 pixel, type of font is accounted
        sz = pDc->GetOutputTextExtent(subItemText.c_str());
        if (static_cast<int>(sz.cx) > ColWidth[col])
          ColWidth[col] = sz.cx; 
      }
    } 
    GetListCtrl().ReleaseDC (pDc);
    for (int col = 0; col < NumCol; ++col) 
    {
      SetColumnWidth(col, ColWidth[col]);
    }

As result width of the column is on 20/30% larger than one of the largest string in that column. I want that width of column will be equal to width of string with max length.

Thanks in advance!

Answer 1

This is probably because you didn't select the correct font into the device context. Try this :

    tstring subItemText;
    CDC* pDc = GetListCtrl().GetDC(); 

    CFont *normalfont = GetListCtrl().GetFont() ;
    CFont *oldfont = pDc->SelectObject(normalfont) ;

    for (int row = GetItemCount() - 1; row >= 0; --row) 
    {
      subItemText = _T("");
      for (int col = 0; col < NumCol; ++col)  
      {
        subItemText = this->GetSubItemString( GetItemData(row), col);
        CSize sz; 
        // get length of the string in logical units, by default 1 unit == 1 pixel, type of font is accounted
        sz = pDc->GetOutputTextExtent(subItemText.c_str());
        if (static_cast<int>(sz.cx) > ColWidth[col])
          ColWidth[col] = sz.cx; 
      }
    } 

    pDc->SelectObject(oldfont) ;

    GetListCtrl().ReleaseDC (pDc);
    for (int col = 0; col < NumCol; ++col) 
    {
      SetColumnWidth(col, ColWidth[col]);
    }

Answer 2

I think all you need is this:

SetColumnWidth(col, LVSCW_AUTOSIZE);

In my projects, I derive my own class from CListCtrl and use the following function

void CMyListCtrl::AutoSizeColumnWidths()
{
    // size column widths to content
    int nNumColumns = GetHeaderCtrl()->GetItemCount();

    // for all columns ...
    for (int i = 0; i < nColumnCount; i++)
    {
        // find max of content vs header
        SetColumnWidth(i, LVSCW_AUTOSIZE);
        int nColumnWidth = GetColumnWidth(i);
        SetColumnWidth(i, LVSCW_AUTOSIZE_USEHEADER);
        int nHeaderWidth = GetColumnWidth(i); 

        // set width to max 
        SetColumnWidth(i, max(nColumnWidth, nHeaderWidth));
    }
    SetRedraw(TRUE);
} 

This makes sure that columns with no content still get sized according to the header text.