Uncorrect sorting of columns ClistCtrl

Question

That's my callback function:

int CALLBACK SortMeAscending(LPARAM lParam1, LPARAM lParam2, LPARAM lParamSort)
    {
        int nRetVal = 0;

        PITEMDATA pData1 = (PITEMDATA)lParam1;
        PITEMDATA pData2 = (PITEMDATA)lParam2;

        switch(lParamSort)
        {
        case 0:
            if(pData1->iSeq < pData2->iSeq)
                nRetVal = -1;
            else if(pData1->iSeq > pData2->iSeq)
                nRetVal = 1;
            else
                nRetVal = 0;
            break;

        case 1:
            nRetVal = lstrcmp(pData2->pszCueName, pData1->pszCueName);
            break;
        case 2: 
            nRetVal = lstrcmp(pData2->pszTags, pData1->pszTags);
            break;

        default:
            break;
        }

        return nRetVal;
    }

    int CALLBACK SortMeDescending(LPARAM lParam1, LPARAM lParam2, LPARAM lParamSort)
    {
        int nRetVal = 0;

        PITEMDATA pData1 = (PITEMDATA)lParam1;
        PITEMDATA pData2 = (PITEMDATA)lParam2;

        switch(lParamSort)
        {
        case 0:
            if(pData1->iSeq > pData2->iSeq)
                nRetVal = -1;
            else if(pData1->iSeq < pData2->iSeq)
                nRetVal = 1;
            else
                nRetVal = 0;
            break;

        case 1:
            nRetVal = lstrcmp(pData1->pszCueName, pData2->pszCueName);
            break;
        case 2: 
            nRetVal = lstrcmp(pData1->pszTags, pData2->pszTags);
            break;

        default:
            break;
        }

        return nRetVal;
    }

that's my OnCompareItems:

int CTest::OnCompareItems(LPARAM lParam1, LPARAM lParam2, int iColumn)
{  
    CMFCHeaderCtrl &headerCntrl = GetHeaderCtrl();

    BOOL b = 0;
    if(headerCntrl.IsAscending())
    {
        return SortItems(SortMeDescending, iColumn);
    }
    else
    {
        return SortItems(SortMeAscending, iColumn);
    }
}

If I follow this post http://support.microsoft.com/kb/250614 I don't have arrows of sorting in headers. If I use my method that you can see above, I get some gap in sorting. I click it sorts and next time it won't be sort and again and again please help me

Answer 1

I think you need to use CMFCHeaderCtrl::SetSortColumn to set the column's sort order. every time you sort. In addition to that, the actual sort function should be called from the HDN_ITEMCLICK handler.

So, assuming you have specified this:

ON_NOTIFY(HDN_ITEMCLICK, 0, OnItemclickList1)

In the OnItemclickList1 method write this code:

void CTest::OnItemclickList1(NMHDR* pNMHDR, LRESULT* pResult) 
{  
    NMLISTVIEW *pLV = (NMLISTVIEW *) pNMHDR;
    CMFCHeaderCtrl &headerCntrl = GetHeaderCtrl();

    BOOL b = 0;
    if(headerCntrl.IsAscending())
    {
        headerCntrl.SetSortColumn(pLV->iItem, FALSE);
        SortItems(SortMeDescending, pLV->iItem);
    }
    else
    {
        headerCntrl.SetSortColumn(pLV->iItem, TRUE);
        SortItems(SortMeAscending, iColumn);
    }
    *pResult = 0;
}

and ditch your OnCompareItems