4.MFC程序的初始化過(guò)程

MFC程序的初始化過(guò)程2023/6/251Frame2的類層次及其成員2023/6/252CWinApp::InitApplication()InitApplication是CWinApp的虛函數(shù)，負(fù)責(zé)“每個(gè)程序只做一次”（只有第一個(gè)實(shí)例才會(huì)進(jìn)入）的操作放在其中，如：注冊(cè)窗口（RegisterClass）窗口類只需注冊(cè)一次，即可供同一程序的后續(xù)每一個(gè)實(shí)例（instance）使用2023/6/253CWinApp::InitInstance()InitInstance是CWinApp的虛函數(shù)，負(fù)責(zé)“每一個(gè)例程都得做一次”（任何實(shí)例都會(huì)進(jìn)入）的操作即放在其中，如：產(chǎn)生窗口（CreateWindow）產(chǎn)生窗口是每一個(gè)實(shí)例（instance）都得進(jìn)行的操作2023/6/254窗口類通常，系統(tǒng)會(huì)為我們注冊(cè)一些標(biāo)準(zhǔn)的窗口類（以及一些標(biāo)準(zhǔn)的窗口函數(shù)）我們（程序設(shè)計(jì)者）應(yīng)該在我們的CMyWinApp中改寫(xiě)InitInstance，并在其中把窗口產(chǎn)生出來(lái)在標(biāo)準(zhǔn)的窗口類中指定自己的窗口標(biāo)題和菜單2023/6/255Frame2//MY.CPPCMyWinApptheApp;voidmain(){ CWinApp*pApp=AfxGetApp(); pApp->InitApplication(); pApp->InitInstance(); pApp->Run();}2023/6/256Frame2//MY.CPPCMyWinApptheApp;voidmain(){ CWinApp*pApp=AfxGetApp();

pApp->InitApplication(); pApp->InitInstance(); pApp->Run();}調(diào)用的是CWinApp::InitApplication2023/6/257Frame2//MY.CPPCMyWinApptheApp;voidmain(){ CWinApp*pApp=AfxGetApp(); pApp->InitApplication();

pApp->InitInstance(); pApp->Run();}調(diào)用的是CMyWinApp::InitInstance2023/6/258Frame2//MY.CPPCMyWinApptheApp;voidmain(){ CWinApp*pApp=AfxGetApp(); pApp->InitApplication(); pApp->InitInstance();

pApp->Run();}調(diào)用的是CWinApp::Run2023/6/259CMyWinApp::InitInstanceBOOLCMyWinApp::InitInstance(){cout<<"CMyWinApp::InitInstance\n";m_pMainWnd=newCMyFrameWnd;returnTRUE;}2023/6/2510CMyWinApp::InitInstanceBOOLCMyWinApp::InitInstance(){cout<<"CMyWinApp::InitInstance\n";

m_pMainWnd=newCMyFrameWnd;

returnTRUE;}引發(fā)CMyFrameWnd::CMyFrameWnd構(gòu)造函數(shù)2023/6/2511CMyWinApp::InitInstanceBOOLCMyWinApp::InitInstance(){cout<<"CMyWinApp::InitInstance\n";

m_pMainWnd=newCMyFrameWnd;

returnTRUE;}CMyFrameWnd::CMyFrameWnd(){ Create();}2023/6/2512CMyWinApp::InitInstanceBOOLCMyWinApp::InitInstance(){cout<<"CMyWinApp::InitInstance\n";

m_pMainWnd=newCMyFrameWnd;

returnTRUE;}CMyFrameWnd::CMyFrameWnd(){

Create();}Create是虛函數(shù)，但CMyFrameWnd未改寫(xiě)它，所以引發(fā)父類的CFrameWnd::Create2023/6/2513CMyWinApp::InitInstanceCMyFrameWnd::CMyFrameWnd(){

Create();}BOOLCFrameWnd::Create(){cout<<"CFrameWnd::Create\n";CreateEx();returnTRUE;}2023/6/2514CMyWinApp::InitInstanceCMyFrameWnd::CMyFrameWnd(){

Create();}BOOLCFrameWnd::Create(){cout<<"CFrameWnd::Create\n";

CreateEx();returnTRUE;}CreateEx不是虛函數(shù)，它繼承自CWnd，而CFrameWnd之中又不曾重新定義它，所以調(diào)用的是CWnd::CreateEx2023/6/2515CMyWinApp::InitInstanceBOOLCFrameWnd::Create(){cout<<"CFrameWnd::Create\n";

CreateEx();returnTRUE;}BOOLCWnd::CreateEx(){cout<<"CWnd::CreateEx\n";PreCreateWindow();returnTRUE;}2023/6/2516CMyWinApp::InitInstanceBOOLCFrameWnd::Create(){cout<<"CFrameWnd::Create\n";

CreateEx();returnTRUE;}BOOLCWnd::CreateEx(){cout<<"CWnd::CreateEx\n";

PreCreateWindow();returnTRUE;}這是一個(gè)虛函數(shù)，CWnd中有定義，CFrameWnd也改寫(xiě)了它。那么此處到底調(diào)用的是哪一個(gè)：CWnd::PreCreateWindow還是CFrameWnd::PreCreateWindow2023/6/2517CMyWinApp::InitInstanceBOOLCWnd::CreateEx(){cout<<"CWnd::CreateEx\n";

PreCreateWindow();returnTRUE;}BOOLCFrameWnd::PreCreateWindow(){cout<<"CFrameWnd::PreCreateWindow\n";returnTRUE;}2023/6/2518CMyWinApp::InitInstanceBOOLCWnd::CreateEx(){cout<<