FIX: CListCtrl::InsertColumn() Causes Column Data to ShiftLast reviewed: September 19, 1997Article ID: Q151897 |
The information in this article applies to:
SYMPTOMSAfter 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.
CAUSEThis is a bug in the Listview control. Sending an LVM_INSERTCOLUMN after data has already been inserted, causes this problem.
WORKAROUNDThere are several ways to work around this problem:
Method #1Use 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 #2Create 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 #3Reset the contents of the CListCtrl via DeleteAllItems() and add all column data again after calling InsertColumn().
STATUSMicrosoft 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 */ Keywords : MfcUI vcbuglist400 vcfixlist500 kbprg kbbuglist kbfixlist Technology : kbMfc Version : 4.0 4.1 4.2 Platform : NT WINDOWS Issue type : kbbug Solution Type : kbfix |
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