Create Thumbnail Extractor Objects for Your MFC Document Types

// ScribbleExtractor.h : Declaration of the CScribbleExtractor

#ifndef __SCRIBBLEEXTRACTOR_H_
#define __SCRIBBLEEXTRACTOR_H_

#include "resource.h"				// main symbols
#include <shlguid.h>
#include <AtlCom.h>
#include <shlobj.h>
//#include <shobjidl.h>
#include "IExtractImage.h"

/////////////////////////////////////////////////////////////////////////////
// CScribbleExtractor
class ATL_NO_VTABLE CScribbleExtractor : 
	public CComObjectRootEx<CComSingleThreadModel>,
	public CComCoClass<CScribbleExtractor, &CLSID_ScribbleExtractor>,
	public IPersistFile,
	public IExtractImage2
{
public:
	CScribbleExtractor()
	{
	}

DECLARE_REGISTRY_RESOURCEID(IDR_THUMBSCB)

DECLARE_PROTECT_FINAL_CONSTRUCT()

BEGIN_COM_MAP(CScribbleExtractor)
	COM_INTERFACE_ENTRY(IPersistFile)
	COM_INTERFACE_ENTRY(IExtractImage)
	COM_INTERFACE_ENTRY(IExtractImage2)
END_COM_MAP()

// IExtractImage
public:

	STDMETHOD(GetLocation)(LPWSTR pszPathBuffer,
						   DWORD cchMax,
						   DWORD *pdwPriority,
						   const SIZE *prgSize,
						   DWORD dwRecClrDepth,
						   DWORD *pdwFlags);
	STDMETHOD(Extract)(HBITMAP*);
// IExtractImage2
  STDMETHOD(GetDateStamp)(FILETIME *pDateStamp);

// IPersistFile
	STDMETHOD(Load)(LPCOLESTR wszFile, DWORD dwMode);

	STDMETHOD(GetClassID)(LPCLSID clsid)
		{ MessageBox(0,"GetClassID",0,0);

		return E_NOTIMPL;	}

	STDMETHOD(IsDirty)(VOID)
	{ MessageBox(0,"IsDirty",0,0);
	return E_NOTIMPL; }

	STDMETHOD(Save)(LPCOLESTR, BOOL)
	{ 		MessageBox(0,"Save",0,0);
		return E_NOTIMPL; }

	STDMETHOD(SaveCompleted)(LPCOLESTR)
	{ 
		MessageBox(0,"SaveCompleted",0,0);
		return E_NOTIMPL; }

	STDMETHOD(GetCurFile)(LPOLESTR FAR*)
	{ MessageBox(0,"GetCurFile",0,0);
		return E_NOTIMPL; }

private:
	SIZE m_bmSize;
	HBITMAP m_hPreview;
	TCHAR m_szFile[500];
};

#endif //__ICONEXTRACTOR_H_