private int OpenFileSubClass
    (
        IntPtr hWnd,
        uint uMsg,
        IntPtr wParam,
        IntPtr lParam,
        IntPtr uIdSubclass,
        uint dwRefData
    )
    {
      switch (uMsg)
      {
        case InteropUtil.WM_PARENTNOTIFY:
          {
            unchecked
            {
              var id = lParam.GetDlgCtrlID();

              if (LOW((uint)wParam) == InteropUtil.WM_CREATE && (id == InteropUtil.ID_FileList || id == 0))
              {
                lParam.SetWindowSubclass(m_defViewSubClassDelegate, 0, 0);
              }
            }
            break;
          }
      }
      return hWnd.DefSubclassProc(uMsg, wParam, lParam);
    }
    private int DefViewSubClass
    (
        IntPtr hWnd,
        uint uMsg,
        IntPtr wParam,
        IntPtr lParam,
        IntPtr uIdSubclass,
        uint dwRefData
    )
    {
      if (uMsg == InteropUtil.WM_NOTIFY)
      {
        var header = (InteropUtil.NMHDR)Marshal.PtrToStructure(lParam, typeof(InteropUtil.NMHDR));
        if (header.code == InteropUtil.LVN_ITEMCHANGED && header.hwndFrom != IntPtr.Zero && header.idFrom == 1)
        {
          var nmListView = (InteropUtil.NMLISTVIEW)Marshal.PtrToStructure(lParam, typeof(InteropUtil.NMLISTVIEW));
          var oldSelected = (nmListView.uOldState & InteropUtil.LVIS_SELECTED) != 0;
          var newSelected = (nmListView.uNewState & InteropUtil.LVIS_SELECTED) != 0;
          if (!oldSelected && newSelected)
          {
            if (!m_suppressSelectionChange)
            {
              //the item went from not selected to being selected    
              //so we want to look and see if the selected item is a folder, and if so
              //change the text of the item box to be the item on the folder. But, before we do that
              //we want to make sure that the box isn't currently focused.
              var hParent = hWnd.GetParent();
              var hFNCombo = hParent.GetDlgItem(InteropUtil.ID_FileNameCombo);
              var hFNEditBox = hParent.GetDlgItem(InteropUtil.ID_FileNameTextBox);
              var hFocus = InteropUtil.GetFocus();

              if
              (
                  (hFNCombo == IntPtr.Zero || hFNCombo != hFocus) &&
                  (hFNEditBox == IntPtr.Zero || hFNEditBox != hFocus)
              )
              {
                SetFileNameToSelectedItem(header.hwndFrom, hFNCombo, nmListView.iItem);
              }
            }
            m_suppressSelectionChange = false;
          }
        }
      }
      return hWnd.DefSubclassProc(uMsg, wParam, lParam);
    }