CView類建立過程

BOOL A::CreateView(LPCTSTR lpszLabel,CRuntimeClass * pViewClass, CCreateContext *pContext)
{
CRect rect, client;
ASSERT(pViewClass && pContext);

//CWnd *pParent = NULL;
CWnd *pWnd = NULL;
int dwStyle = 0;

pWnd = (CWnd *)pViewClass->CreateObject();

if (!pWnd) return FALSE;

//
ASSERT(pWnd);
    if (!pWnd->Create(NULL, NULL, dwStyle, rect, this, 13576+m_viewList.GetCount() ))
    {
        TRACE0("Warning: couldn't create client area for tab view\n");
        // pWnd will be cleaned up by PostNcDestroy
return FALSE;

    }

    .............

}

BOOL CWnd::Create(LPCTSTR lpszClassName,
LPCTSTR lpszWindowName, DWORD dwStyle,
const RECT& rect,
CWnd* pParentWnd, UINT nID,
CCreateContext* pContext)
{
// can't use for desktop or pop-up windows (use CreateEx instead)
ASSERT(pParentWnd != NULL);
ASSERT((dwStyle & WS_POPUP) == 0);

return
CreateEx(0, lpszClassName, lpszWindowName,
dwStyle | WS_CHILD,
rect.left, rect.top,
rect.right - rect.left, rect.bottom - rect.top,
pParentWnd->GetSafeHwnd(), (HMENU)(UINT_PTR)nID, (LPVOID)pContext);
}

BOOL CWnd::CreateEx(DWORD dwExStyle, LPCTSTR lpszClassName,
LPCTSTR lpszWindowName, DWORD dwStyle,
int x, int y, int nWidth, int nHeight,
HWND hWndParent, HMENU nIDorHMenu, LPVOID lpParam)
{
ASSERT(lpszClassName == NULL || AfxIsValidString(lpszClassName) || 
AfxIsValidAtom(lpszClassName));
ENSURE_ARG(lpszWindowName == NULL || AfxIsValidString(lpszWindowName));

// allow modification of several common create parameters
CREATESTRUCT cs;
cs.dwExStyle = dwExStyle;
cs.lpszClass = lpszClassName;
cs.lpszName = lpszWindowName;
cs.style = dwStyle;
cs.x = x;
cs.y = y;
cs.cx = nWidth;
cs.cy = nHeight;
cs.hwndParent = hWndParent;
cs.hMenu = nIDorHMenu;
cs.hInstance = AfxGetInstanceHandle();
cs.lpCreateParams = lpParam;

if (!PreCreateWindow(cs))
{
PostNcDestroy();
return FALSE;
}

AfxHookWindowCreate(this);
HWND hWnd = ::AfxCtxCreateWindowEx(cs.dwExStyle, cs.lpszClass,
cs.lpszName, cs.style, cs.x, cs.y, cs.cx, cs.cy,
cs.hwndParent, cs.hMenu, cs.hInstance, cs.lpCreateParams);

#ifdef _DEBUG
if (hWnd == NULL)
{
TRACE(traceAppMsg, 0, "Warning: Window creation failed: GetLastError returns 0x%8.8X\n",
GetLastError());
}
#endif

if (!AfxUnhookWindowCreate())
PostNcDestroy();        // cleanup if CreateWindowEx fails too soon

if (hWnd == NULL)
return FALSE;
ASSERT(hWnd == m_hWnd); // should have been set in send msg hook
return TRUE;
}

BOOL CView::PreCreateWindow(CREATESTRUCT & cs)
{
ASSERT(cs.style & WS_CHILD);

if (cs.lpszClass == NULL)
{
VERIFY(AfxDeferRegisterClass(AFX_WNDFRAMEORVIEW_REG));
cs.lpszClass = _afxWndFrameOrView;  // COLOR_WINDOW background
}

if (cs.style & WS_BORDER)
{
cs.dwExStyle |= WS_EX_CLIENTEDGE;
cs.style &= ~WS_BORDER;
}

return TRUE;
}