CWindow::Create Failure

From:

"NickP" <a@a.com>

Newsgroups:

microsoft.public.vc.language

Date:

Tue, 17 Oct 2006 18:24:35 +0100

Message-ID:

<#urEpEh8GHA.2092@TK2MSFTNGP03.phx.gbl>

Hi there,

    I have a class derived from CWindowImpl and I am handling the WM_CREATE
message via a message handler and map.

    -----------

    BEGIN_MSG_MAP(CMyWindow)
        MESSAGE_HANDLER(WM_CREATE, OnCreate)
    END_MSG_MAP()

    LRESULT OnCreate(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/,
BOOL& /*bHandled*/);

    LRESULT CFlashView::OnCreate(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM
lParam, BOOL& /*bHandled*/)
    {
        #if FLASH
            cWndChildWindow = CWindow::Create(WC_MYWINDOWCLASS, m_hWnd,
NULL, NULL, WS_CHILD);
            cWndChildWindow.ShowWindow(SW_SHOW);
        #endif
        return(0);
    }

    -----------

    In the OnCreate method I would like to create an instance of a child
window that needs to be displayed in this window. But for some reason I am
greeted with an Assertion Failure with the expression

    m_hWnd == 0
    ...
    ATLASSUME(m_hWnd == NULL)

    Now is this telling me that m_hWnd needs to be 0? or can't be 0?

    m_hWnd is the handle to CMyWindow and at this point it should have been
created right? This is really confusing me, if I pass 0 to the method it
continues but then fails on the next line as CWndChildWindow was never
created. cWndChildWindow is a CWindow object.

    Any help would be greatly appreciated! Thanks for your time in advance.

Nick.