实现SDI与MDI的转换

如果想将一个编好的SDI应用程序转换为MDI，首先要建立一个继承于CMDIChidWnd的类，假设为CChldFrm，在CWinApp中作如下变化。

InitInstance()

{

. ...

//instead of adding CSingleDocTemplate

// Add CMultiDocTemplate.

pDocTemplate = new CMultiDocTemplate(

IDR_MAINFRAME,

RUNTIME_CLASS(CSDIDoc),

RUNTIME_CLASS(CChldFrm),

// For Main MDI Frame change this frame window from

// CFrameWnd derivative ( i.e. CMainFrame )

// to your CMDIChildWnd derived CChldFrm.

RUNTIME_CLASS(CSDIView));

/// After this it is required to create the main frame window

// which will contain all the child windows. Now this window is

// what was initially frame window for SDI.

CMainFrame* pMainFrame = new CMainFrame;

if (!pMainFrame->LoadFrame(IDR_MAINFRAME))

return FALSE;

m_pMainWnd = pMainFrame;

.....

}

在从CMDIFrameWnd中继承的类CMainFrame代替CFramWnd后，所有的类都将从CMDIFrame继承，而不是CFrameWnd,编译运行后你就会发现程序已经从SDI变换到MDI。

注意：在CMainFram中必须将构造函数从private改为public.否则会出错。