mfc, why is this class abstract?!

microsoft.public.vc.mfc - Microsoft Visual C


mfc >> why is this class abstract?!

by Edward Walker » Mon, 24 Nov 2003 22:45:38 GMT

i have looked all over this class and cant figure out why its abstract.
below are the header files for it. the first one is a regular class called
CCeFileFilterSite, which is derived from an interface called
ICeFileFilterSite (it's header file is below the CCeFileFilterSite header
file) which is derrived from IUnknown. i've been looking at this code for
days and cant figure out why CCeFileFilterSite is abstract.

thanks for any help you can give me,
edward

CCeFileFilterSite header file:
#pragma once

#include "ICeFileFilterSite.h"

class CCeFileFilterSite : public ICeFileFilterSite

{

public:

CCeFileFilterSite(void);

~CCeFileFilterSite(void);

virtual HRESULT OpenSourceFile(int nHowToOpenFile, LPVOID* ppObj);

virtual HRESULT OpenDestinationFile(int nHowToOpenFile, LPCTSTR pszFullpath,
LPVOID* ppObj);

virtual HRESULT CloseSourceFile(LPUNKNOWN pObj);

virtual HRESULT CloseDestinationFile(BOOL bKeepFile, LPUNKNOWN pObj);

virtual HRESULT ReportProgress(UINT nPercent);

virtual HRESULT ReportLoss(DWORD dw, LPCTSTR psz, va_list args);

};



ICeFileFilterSite header file:

#pragma once

// {6C5C05E0-97A2-11cf-8011-00A0C90A8F78}

DEFINE_GUID(IID_ICeFileFilterSite,

0x6c5c05e0, 0x97a2, 0x11cf, 0x80, 0x11, 0x0, 0xa0, 0xc9, 0xa, 0x8f, 0x78);

//

// ICeFileFilterSite interface provided by Windows CE Services

//

#undef INTERFACE

#define INTERFACE ICeFileFilterSite

//DECLARE_INTERFACE_(ICeFileFilterSite, IUnknown)

interface ICeFileFilterSite : public IUnknown

{

// *** ICeFileFilterSite methods ***

virtual HRESULT OpenSourceFile(int nHowToOpenFile, LPVOID *ppObj);

virtual HRESULT OpenDestinationFile(int nHowToOpenFile, LPCTSTR pszFullpath,
LPVOID *ppObj);

virtual HRESULT CloseSourceFile(LPUNKNOWN pObj);

virtual HRESULT CloseDestinationFile(BOOL bKeepFile, LPUNKNOWN pObj);

virtual HRESULT ReportProgress(UINT nPercent);

virtual HRESULT ReportLoss(DWORD dw, LPCTSTR psz, va_list args);

};



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mfc >> why is this class abstract?!

by Doug Harrison [MVP] » Tue, 25 Nov 2003 00:45:50 GMT






Are the IUnknown members implemented?

--
Doug Harrison
Microsoft MVP - Visual C++


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mfc >> why is this class abstract?!

by Edward Walker » Tue, 25 Nov 2003 08:45:03 GMT

sometimes its the obvious that will kill you. no they're not.

thanks alot,
edward





called
for



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