C / C++ / MFC

softwaremonkey wrote:

because in changing the state of an item, it causes OnItemchangingLoadingValues() to be called again.

void CSpecimenLoadingDialog::OnItemchangingLoadingValues(NMHDR* pNMHDR, LRESULT* pResult)
{
    if (nCheckedItems < 2)
    {
        if (pNMHDR's new state equals checked)
            nCheckedItems++;
        else
            nCheckedItems--;
    }
}

 // Header file
private:
    m_bIgnoreChgHandling;

// Source file
CSpecimenLoadingDialog::CSpecimenLoadingDialog()
{
    m_bIgnoreChgHandling = false;
}

void CSpecimenLoadingDialog::OnItemchangingLoadingValues(NMHDR* pNMHDR, LRESULT* pResult) 
{
    // Alternative: Use static variable here
    // static bool m_bIgnoreChgHandling = false;
    if (!m_bIgnoreChgHandling)
    {
        NM_LISTVIEW* pNMListView = (NM_LISTVIEW*)pNMHDR;
        int nCheckedItems = 0;
        // some handling code
        if(nCheckedItems == 2)
        {
            m_bIgnoreChgHandling = true;
            ListView_SetItemState(m_loadingVals.m_hWnd, pNMListView->iItem, FALSE, LVIS_STATEIMAGEMASK);
            m_bIgnoreChgHandling = false;
        }
    }
    *pResult = 0;
}