DOCUMENT:Q151897  06-MAY-2001  [visualc]
TITLE   :FIX: CListCtrl::InsertColumn() Causes Column Data to Shift
PRODUCT :Microsoft C Compiler
PROD/VER:winnt:4.0,4.1,4.2
OPER/SYS:
KEYWORDS:kbListView kbMFC KbUIDesign kbVC kbVC420 kbVC500fix kbGrpDSMFCATL

======================================================================
-------------------------------------------------------------------------------
The information in this article applies to:

 - The Microsoft Foundation Classes (MFC), used with:
    - Microsoft Visual C++, 32-bit Editions, versions 4.0, 4.1 
    - Microsoft Visual C++, 32-bit Enterprise Edition, version 4.2 
    - Microsoft Visual C++, 32-bit Professional Edition, version 4.2 
-------------------------------------------------------------------------------

SYMPTOMS
========

After adding items to a CListCtrl, if you call InsertColumn() to add additional
columns, column data starting from the second column will be shifted right. For
example, if you initially create two columns and add your items, adding a third
column will cause the data from the second column to disappear and reappear in
the third column. You may need to force a repaint (minimize the window and
restore it) to see the changes.

CAUSE
=====

This is a bug in the Listview control. Sending an LVM_INSERTCOLUMN after data
has already been inserted, causes this problem.

RESOLUTION
==========

There are several ways to work around this problem:

Method #1
---------

Use LPSTR_TEXTCALLBACK in the call to InsertItem(). This will cause a
notification LVN_GETDISPINFO to be sent to the parent of the CListCtrl each time
the text for each item is needed. The handler for this notification will then
fill in the appropriate text for each item.

Method #2
---------

Create all the columns up front before adding any items. You can hide columns by
setting their initial width to zero in the call to InsertColumn(). To show
columns, you can call SetColumnWidth() or SetColumn(). The only drawback to this
method is that the user can still resize the column by dragging in the header
control.

Method #3
---------

Reset the contents of the CListCtrl via DeleteAllItems() and add all column data
again after calling InsertColumn().

STATUS
======

Microsoft has confirmed this to be a problem in the Microsoft products listed at
the beginning of this article. This bug has been fixed in COMCTL32.DLL which as
been released with Microsoft Windows NT 4.0 and Microsoft Internet Explorer
3.01.

MORE INFORMATION
================

Sample Code
-----------

Method #1
---------

      // m_pList is of type CListCtrl*
      BEGIN_MESSAGE_MAP(CTestView, CView)
           ON_NOTIFY (LVN_GETDISPINFO, IDC_LIST, OnGetDispInfo)
      END_MESSAGE_MAP()

         int CTestView::OnCreate(LPCREATESTRUCT lpCreateStruct)
         {
             // create CListCtrl and columns
         ...
             // insert item; text will be set in LVN_GETDISPINFO
             m_pList->InsertItem (iIndex, LPSTR_TEXTCALLBACK);
         ...
         }

         void CTestView::OnGetDispInfo (NMHDR* pnmhdr, LRESULT* pResult)
         {
             LV_DISPINFO* pdi = (LV_DISPINFO *) pnmhdr;

             // set text for column #1
             if (0 == pdi->item.iSubItem)
                 pdi->item.pszText = "1st Column Data";
             // set text for column #2
             else if (1 == pdi->item.iSubItem)
                 pdi->item.pszText = "2nd Column Data";
             // set text for column #3
             else if (2 == pdi->item.iSubItem)
                 pdi->item.pszText = "3rd Column Data";
         }

Method #2
---------

      int CTestView::OnCreate(LPCREATESTRUCT lpCreateStruct)
      {
          // create CListCtrl and columns
          ...
          // create 3rd column with zero width so it is not visible
          m_pList->InsertColumn (2, "", LVCFMT_LEFT, 0);
          // add items
          ...
          return 0;
      }

      // this function makes the 3rd column appear
      void CTestView::AddColumn()
      {
          LV_COLUMN lvc;

          lvc.mask = LVCF_TEXT | LVCF_WIDTH;
          lvc.cx = 100;
          lvc.pszText = "Column #3";
          // set the text and width of column #3
          m_pList->SetColumn (2, &lvc);
      }

      /* Compile options needed: default
      */ 

Additional query words: kbVC400bug

======================================================================
Keywords          : kbListView kbMFC KbUIDesign kbVC kbVC420 kbVC500fix kbGrpDSMFCATL 
Technology        : kbAudDeveloper kbMFC
Version           : winnt:4.0,4.1,4.2
Issue type        : kbbug
Solution Type     : kbfix

=============================================================================

THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS
PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND.  MICROSOFT DISCLAIMS
ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES
OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.  IN NO
EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR
ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL,
CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF
MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE
POSSIBILITY OF SUCH DAMAGES.  SOME STATES DO NOT ALLOW THE EXCLUSION
OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES
SO THE FOREGOING LIMITATION MAY NOT APPLY.

Copyright Microsoft Corporation 2001.