How to catch the click event of checkbox which is in a listctrl cell?

Question

Insert checkbox column on a listctrl

I made a list with a checkbox column consulting the answer above.

Now my superior asks me to disable the OK button at first, enable it when at least there is one line is checked.

I looked up seems there is easy way to catch the click event when a checkbox is in a listctrl.

Answer 1

Add LVN_ITEMCHANGED to the message map. This will notify the dialog when changes are made to the list item:

BEGIN_MESSAGE_MAP(CMyDialog, CDialogEx)
    ON_NOTIFY(LVN_ITEMCHANGED, IDC_LIST1, OnItemChanged)
    ...
END_MESSAGE_MAP()

Next, handle the message and respond each time a list item is checked or unchecked. Then you have to go through all the items in the list box and use CListCtrl::GetCheck. Example:

void CMyDialog::OnItemChanged(NMHDR* pNMHDR, LRESULT*)
{
    NMLISTVIEW* pNMListView = (NM_LISTVIEW*)pNMHDR;
    if(pNMListView->uChanged & LVIF_STATE)
    {
        if(pNMListView->uNewState & LVIS_STATEIMAGEMASK && pNMListView->iItem >= 0)
        {
            BOOL checked_once = FALSE;
            for(int i = 0; i < m_list.GetItemCount(); i++)
                if(m_list.GetCheck(i))
                    checked_once = TRUE;
            GetDlgItem(IDOK)->EnableWindow(checked_once);
        }
    }
}

You can add GetDlgItem(IDOK)->EnableWindow(FALSE); in OnInitDialog so that the OK button is initially disabled.

Side note, your dialog is using the old style look. See this link on using the modern style UI: Upgraded MFC application still looks old