MFC Dialog: How to disable a dialog from being moved?

Q: How to disbale a dialog from being moved?

A: There are two possibilites when moving a dialog, by click and drag the caption area of the dialog or by using the system menu "move" item and then move the dialog. I will describe how to disable both.

To disable the user from click and drag on the caption of the dialog, you have to handle the WM_NCHITTEST message. You call the base class and check the return value of the CDialog::OnNcHitTest(point) function:

Code:

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LRESULT CYourDlg::OnNcHitTest(CPoint point)
{
        LRESULT res = CDialog::OnNcHitTest(point);
        if( res == HTCAPTION)
                res = HTNOWHERE;
        return res;
}

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Regarding the system menu, you can either disble the "Move" item or completely remove it.

To disable it, handle the WM_INITMENUPOPUP message in your dialog:

Code:

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void CYourDlg::OnInitMenuPopup(CMenu* pPopupMenu, UINT nIndex, BOOL bSysMenu)
{
        CDialog::OnInitMenuPopup(pPopupMenu, nIndex, bSysMenu);

        if ( bSysMenu )
        {
                pPopupMenu->EnableMenuItem( SC_MOVE,
                        MF_BYCOMMAND | MF_DISABLED | MF_GRAYED );
        }
}

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To remove the "Move" item from the system menu, add the following at the end of your OnInitDialog function:

Code:

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CMenu *pMenu = GetSystemMenu(FALSE);
pMenu->DeleteMenu(SC_MOVE,MF_BYCOMMAND);

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