UserUI程序实现过程简述

1.__tmainCRTStartup

2.

mainret = _tWinMain( (HINSTANCE)&__ImageBase,
                                 NULL,
                                 lpszCommandLine,
                                 StartupInfo.dwFlags & STARTF_USESHOWWINDOW
                                      ? StartupInfo.wShowWindow
                                      : SW_SHOWDEFAULT
                                );

3.

return AfxWinMain(hInstance, hPrevInstance, lpCmdLine, nCmdShow);

4.

if (!pThread->InitInstance())
    {
        if (pThread->m_pMainWnd != NULL)
        {
            TRACE(traceAppMsg, , "Warning: Destroying non-NULL m_pMainWnd\n");
            pThread->m_pMainWnd->DestroyWindow();
        }
        nReturnCode = pThread->ExitInstance();
        goto InitFailure;
    }

5.

int CWinApp::Run()
{
    if (m_pMainWnd == NULL && AfxOleGetUserCtrl())
    {
        // Not launched /Embedding or /Automation, but has no main window!
        TRACE(traceAppMsg, , "Warning: m_pMainWnd is NULL in CWinApp::Run - quitting application.\n");
        AfxPostQuitMessage();
    }
    return CWinThread::Run();
}

6.

for (;;)
    {
        // phase1: check to see if we can do idle work
        while (bIdle &&
            !::PeekMessage(&(pState->m_msgCur), NULL, NULL, NULL, PM_NOREMOVE))
        {
            // call OnIdle while in bIdle state
            if (!OnIdle(lIdleCount++))
                bIdle = FALSE; // assume "no idle" state
        }

        // phase2: pump messages while available
        do
        {
            // pump message, but quit on WM_QUIT
            if (!PumpMessage())
                return ExitInstance();

            // reset "no idle" state after pumping "normal" message
            //if (IsIdleMessage(&m_msgCur))
            if (IsIdleMessage(&(pState->m_msgCur)))
            {
                bIdle = TRUE;
                lIdleCount = ;
            }

        } while (::PeekMessage(&(pState->m_msgCur), NULL, NULL, NULL, PM_NOREMOVE));
    }

7.

BOOL CWinThread::PumpMessage()
{
  return AfxInternalPumpMessage();
}

8.

if (pState->m_msgCur.message != WM_KICKIDLE && !AfxPreTranslateMessage(&(pState->m_msgCur)))
    {
        ::TranslateMessage(&(pState->m_msgCur));
        ::DispatchMessage(&(pState->m_msgCur));
    }

9.

AfxWndProc(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam)
{
    // special message which identifies the window as using AfxWndProc
    if (nMsg == WM_QUERYAFXWNDPROC)
        ;

    // all other messages route through message map
    CWnd* pWnd = CWnd::FromHandlePermanent(hWnd);
    ASSERT(pWnd != NULL);
    ASSERT(pWnd==NULL || pWnd->m_hWnd == hWnd);
    if (pWnd == NULL || pWnd->m_hWnd != hWnd)
        return ::DefWindowProc(hWnd, nMsg, wParam, lParam);
    return AfxCallWndProc(pWnd, hWnd, nMsg, wParam, lParam);
}