Automatically resorting after an edit


The only time the list view control does some sorting
is when inserting an item into the list. Then too, the control should have
the LVS_SORTASCENDING  or the LVS_SORTDESCENDING  style. The
new item is inserted in its proper place and the other items remain in
the same relative order. If the user edits an item, the list view has to
be explicitly sorted to maintain the order. To achieve this, the resort
code has to be initiated from the LVN_ENDLABELEDIT handler. The code below
uses the SortTextItems() function covered in a previous section. If the
sorting is based on anything other that the text, then the SortItems()
function should be used for sorting.

 

void CMyListCtrl::OnEndLabelEdit(NMHDR* pNMHDR, LRESULT* pResult)
{
        LV_DISPINFO  *plvDispInfo = (LV_DISPINFO *)pNMHDR;
        LV_ITEM          *plvItem = &plvDispInfo->item;


        if (plvItem->pszText != NULL)
        {
                SetItemText(plvItem->iItem, plvItem->iSubItem, plvItem->pszText);
                SortTextItems( 0, TRUE );
        }
        *pResult = FALSE;
}

There are two things that should be noted. First, the item is updated using
SetItemText() before calling the sorting function. If this were not done,
the sorting routing see only the old data. Second, we set *pResult to FALSE.
This is important. Setting a TRUE value tell Windows that the editing change
should be accepted, but the row that was edited is now probably occupied
by another row and it is this row that will get updated.

 

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