DragSource Lib for BCB(DragDrop.h)

//---------------------------------------------------------------------------


// DragSource Lib.


// Copyright (c) 2006, 2007 by Mao yongjun


// All rights reserved


// Add "WINOLEAPI OleInitialize (LPVOID pvReserved)" before use DragDropLib on each thread


// Don't forget "WINOLEAPI OleUninitialize ()" on exit the thread


//---------------------------------------------------------------------------




#ifndef DragDropH


#define DragDropH


#include <oleidl.h>


#include <objidl.h>


#include <vector>


#include <string>




struct THDROP_Files :




std::vector<std::string>...{


void *Create_HDROP() const;


};








struct TDropResult ...{


DWORD Result;




/**//*


* DRAGDROP_S_DROP


* The OLE drag-and-drop operation was successful.


* DRAGDROP_S_CANCEL


* The OLE drag-and-drop operation was canceled.


* E_UNSPEC


* Unexpected error occurred.


*/


DWORD Effect;




/**//*


* typedef enum tagDROPEFFECT


* {


* DROPEFFECT_NONE = 0,


* DROPEFFECT_COPY = 1,


* DROPEFFECT_MOVE = 2,


* DROPEFFECT_LINK = 4,


* DROPEFFECT_SCROLL = 0x80000000


* }DROPEFFECT;


*/


};


//---------------------------------------------------------------------------


TDropResult DoDragDrop(FORMATETC *fmtetc, STGMEDIUM *stgmeds,UINT count=1,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE); //Drag fms,


TDropResult DoDragDrop(CLIPFORMAT ctFormat,DWORD tymed,void *hStorage,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE); //Drag simple type, hStorage will be freed


TDropResult DoDragDrop(char *szText,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE); //Drag Text


TDropResult DoDragDropURL(char *URL,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE|DROPEFFECT_LINK); //Drag URL


TDropResult DoDragDrop(wchar_t *wszText,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE); //Drag Unicode Text


TDropResult DoDragDrop(HBITMAP hBitmap,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE); //Drag Bitmap


TDropResult DoDragDrop(const THDROP_Files &files,


DWORD dwOKEffect=DROPEFFECT_COPY|DROPEFFECT_MOVE|DROPEFFECT_LINK); //Drag Files




HRESULT CreateDataObject (FORMATETC *fmtetc, STGMEDIUM *stgmeds, UINT count, IDataObject **ppDataObject);


HRESULT CreateEnumFormatEtc (UINT cfmt, FORMATETC *afmt, IEnumFORMATETC **ppEnumFormatEtc);


HANDLE MemToHandle (void *pMem, int nSize);


//----------------TDropSource-----------------------------------------------------------


class TDropSource


:public IDropSource




...{


private:


ULONG _iRefCount;


public:


// IUnknown members


HRESULT __stdcall QueryInterface(REFIID iid, void **ppv);




ULONG __stdcall AddRef(void) ...{ return ++_iRefCount; }




ULONG __stdcall Release(void) ...{ if(--_iRefCount==0)...{delete this; return 0;} return _iRefCount; }




// IDropSource


HRESULT __stdcall QueryContinueDrag(BOOL fEscapePressed,DWORD grfKeyState);


HRESULT __stdcall GiveFeedback(DWORD dwEffect);




//




TDropSource():_iRefCount(1)...{;}




virtual ~TDropSource() ...{;}


};




//----------------TDataObject-----------------------------------------------------------


class TDataObject : public IDataObject




...{


public:


// IUnknown members


HRESULT __stdcall QueryInterface (REFIID iid, void ** ppv);




ULONG __stdcall AddRef (void) ...{ return ++_iRefCount; }




ULONG __stdcall Release (void) ...{ if(--_iRefCount==0)...{delete this; return 0;} return _iRefCount; }




// IDataObject members


HRESULT __stdcall GetData (FORMATETC *pFormatEtc, STGMEDIUM *pStgMedium);


HRESULT __stdcall QueryGetData (FORMATETC *pFormatEtc);


HRESULT __stdcall EnumFormatEtc (DWORD dwDirection, IEnumFORMATETC **ppEnumFormatEtc);






HRESULT __stdcall GetDataHere (FORMATETC *pFormatEtc, STGMEDIUM *pmedium)...{


return DATA_E_FORMATETC;


}




HRESULT __stdcall GetCanonicalFormatEtc (FORMATETC *pFormatEct, FORMATETC *pFormatEtcOut)...{


// Apparently we have to set this field to NULL even though we don't do anything else


pFormatEtcOut->ptd = NULL;


return E_NOTIMPL;


}




HRESULT __stdcall SetData (FORMATETC *pFormatEtc, STGMEDIUM *pMedium, BOOL fRelease)...{


return E_NOTIMPL;


}




HRESULT __stdcall DAdvise (FORMATETC *pFormatEtc, DWORD advf, IAdviseSink *, DWORD *)...{


return OLE_E_ADVISENOTSUPPORTED;


}




HRESULT __stdcall DUnadvise (DWORD dwConnection)...{


return OLE_E_ADVISENOTSUPPORTED;


}




HRESULT __stdcall EnumDAdvise (IEnumSTATDATA **ppEnumAdvise)...{


return OLE_E_ADVISENOTSUPPORTED;


}




// Constructor / Destructor




TDataObject():_iRefCount(1) ...{;}




virtual ~TDataObject ()...{;}




void Add(FORMATETC *fmtetc, STGMEDIUM *stgmeds, UINT count);


void Add(CLIPFORMAT ctFormat,DWORD tymed,void *hStorage);




size_t size()...{return _pFormatEtc.size();}




bool empty()...{return _pFormatEtc.empty();}


void Clear();


void ClearAndRelease();




private:


ULONG _iRefCount;


std::vector<FORMATETC> _pFormatEtc;


std::vector<STGMEDIUM> _pStgMedium;


int LookupFormatEtc(FORMATETC *pFormatEtc);


};




//----------------TEnumFormatEtc-----------------------------------------------------------


class TEnumFormatEtc : public IEnumFORMATETC




...{


public:


// IUnknown members


HRESULT __stdcall QueryInterface (REFIID iid, void ** ppv)




...{


if((iid==IID_IUnknown)||(iid==IID_IEnumFORMATETC))




...{


*ppv=this;


AddRef();


return S_OK;


}


else




...{


*ppv=NULL;


return E_NOINTERFACE;


}


}




ULONG __stdcall AddRef (void) ...{ return ++_iRefCount; }




ULONG __stdcall Release (void) ...{ if(--_iRefCount==0)...{delete this; return 0;} return _iRefCount; }




// IEnumFormatEtc members


HRESULT __stdcall Next (ULONG celt, FORMATETC * rgelt, ULONG * pceltFetched);


HRESULT __stdcall Skip (ULONG celt)




...{


_nIndex += celt;


return (_nIndex <= _nNumFormats) ? S_OK : S_FALSE;


}


HRESULT __stdcall Reset (void)




...{


_nIndex = 0;


return S_OK;


}


HRESULT __stdcall Clone (IEnumFORMATETC ** ppEnumFormatEtc)




...{


HRESULT hResult;


hResult = CreateEnumFormatEtc(_nNumFormats, _pFormatEtc, ppEnumFormatEtc);


if(hResult == S_OK)




...{


((TEnumFormatEtc *)*ppEnumFormatEtc)->_nIndex = _nIndex;


}


return hResult;


}




// Construction / Destruction


TEnumFormatEtc(FORMATETC *pFormatEtc, ULONG nNumFormats);


~TEnumFormatEtc();




private:


LONG _iRefCount; // Reference count for this COM interface


ULONG _nIndex; // current enumerator index


ULONG _nNumFormats; // number of FORMATETC members


FORMATETC * _pFormatEtc; // array of FORMATETC objects


};


//---------------------------------------------------------------------------


#endif