[Dev-C++] why doesn't this work?

[Vlada D. <dj...@im...>]

Hi.
Maybe I'm a little anoying with this, but I'm really confused. I'm =
trying to get an MDI child window to show when I press File->new in the =
menu, but the window does not show, though its name is appnded to Window =
menu every time I press File->New. After I placed the same code in =
WM_CREATE message handler, the window appeared OK. Why is this? Here's a =
piece of my code:

switch(LOWORD(wParam))
            {
                case ID_FILE_NEW:
                {
                    if(nChildCount=3D=3D0)//if there are no child =
windows
                    {
                        CLIENTCREATESTRUCT ccs;
                        =
SetMenu(hFrameWnd,LoadMenu(g_hInstance,MAKEINTRESOURCE(IDM_MENU)));//set =
another menu
                        =
ccs.hWindowMenu=3DGetSubMenu(GetMenu(hFrameWnd),1);
                        ccs.idFirstChild=3DID_FIRST_CHILD;
                       =20
                        =
hMDIClient=3DCreateWindowEx(WS_EX_CLIENTEDGE,"MDICLIENT",(LPCTSTR)NULL,WS=
_CHILD|WS_CLIPCHILDREN,
                        =
CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,hFrameWnd,(HMENU)=
ccs.idFirstChild,
                        g_hInstance,(LPVOID)&ccs);
                        if(!hMDIClient)
                            MessageBox(hFrameWnd,"Can't create client =
wnd","error",MB_OK);
                        ShowWindow(hMDIClient,SW_SHOW);
                       =20
                    }
                    /*create child window*/
                    =
hChildWnd=3DCreateMDIWindow(g_sChildClass,"Untitled",WS_HSCROLL|WS_VSCROL=
L,CW_USEDEFAULT,
                    CW_USEDEFAULT, =
300,200,hMDIClient,g_hInstance,lParam);
                    if(!hChildWnd)
                        MessageBox(hFrameWnd,"Can't create child =
wnd","error",MB_OK);
                    ShowWindow(hChildWnd,SW_SHOW);
                    UpdateWindow(hChildWnd);
                    nChildCount++;// increase number of MDI child =
windows
                }
                break;

Regards,
Vlada