Hiding an MFC dialog box

Question

Ok so I am using this code to hide the taskbar icon of a dialog based MFC application(VC++). The taskbar icon and the dialog box hide whenever I click on the cross or the close

Answer 1

If you show your dialog using CDialog::DoModal() the framework will make sure your dialog is shown. There is only one way to prevent a modal dialog from being shown:

BEGIN_MESSAGE_MAP(CMyDialog, CDialog)
    ON_WM_WINDOWPOSCHANGING()
END_MESSAGE_MAP()

BOOL CHiddenDialog::OnInitDialog()
{
    CDialog::OnInitDialog();
    m_visible = FALSE;

    return TRUE;
}

void CHiddenDialog::OnWindowPosChanging(WINDOWPOS FAR* lpwndpos) 
{
    if (!m_visible)
        lpwndpos->flags &= ~SWP_SHOWWINDOW;

    CDialog::OnWindowPosChanging(lpwndpos);
}