src/Utils/DragDropImpl.cpp

   1 /**************************************************************************
   2    THIS CODE AND INFORMATION IS PROVIDED 'AS IS' WITHOUT WARRANTY OF
   3    ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO
   4    THE IMPLIED WARRANTIES OF MERCHANTABILITY AND/OR FITNESS FOR A
   5    PARTICULAR PURPOSE.
   6    Author: Leon Finker  1/2001
   7 **************************************************************************/
   8 // IDataObjectImpl.cpp: implementation of the CIDataObjectImpl class.
   9 //////////////////////////////////////////////////////////////////////
  10 #include <stdafx.h>
  11 #include <shlobj.h>
  12 #include <atlbase.h>
  13 #include "DragDropImpl.h"
  14
  15 //////////////////////////////////////////////////////////////////////
  16 // CIDataObject Class
  17 //////////////////////////////////////////////////////////////////////
  18
  19 CIDataObject::CIDataObject(CIDropSource* pDropSource):
  20 m_cRefCount(0), m_pDropSource(pDropSource)
  21 {
  22 }
  23
  24 CIDataObject::~CIDataObject()
  25 {
  26         for(int i = 0; i < m_StgMedium.GetSize(); ++i)
  27         {
  28                 ReleaseStgMedium(m_StgMedium[i]);
  29                 delete m_StgMedium[i];
  30         }
  31         for(int j = 0; j < m_ArrFormatEtc.GetSize(); ++j)
  32                 delete m_ArrFormatEtc[j];
  33 }
  34
  35 STDMETHODIMP CIDataObject::QueryInterface(/* [in] */ REFIID riid,
  36 /* [iid_is][out] */ void __RPC_FAR *__RPC_FAR *ppvObject)
  37 {
  38         *ppvObject = NULL;
  39         if (IID_IUnknown==riid || IID_IDataObject==riid)
  40              *ppvObject=this;
  41         /*if(riid == IID_IAsyncOperation)
  42                 *ppvObject=(IAsyncOperation*)this;*/
  43     if (NULL!=*ppvObject)
  44     {
  45         ((LPUNKNOWN)*ppvObject)->AddRef();
  46         return S_OK;
  47     }
  48     return E_NOINTERFACE;
  49 }
  50
  51 STDMETHODIMP_(ULONG) CIDataObject::AddRef( void)
  52 {
  53         return ++m_cRefCount;
  54 }
  55
  56 STDMETHODIMP_(ULONG) CIDataObject::Release( void)
  57 {
  58    long nTemp;
  59    nTemp = --m_cRefCount;
  60    if(nTemp==0)
  61       delete this;
  62    return nTemp;
  63 }
  64
  65 STDMETHODIMP CIDataObject::GetData(
  66     /* [unique][in] */ FORMATETC __RPC_FAR *pformatetcIn,
  67     /* [out] */ STGMEDIUM __RPC_FAR *pmedium)
  68 {
  69         if(pformatetcIn == NULL || pmedium == NULL)
  70                 return E_INVALIDARG;
  71         pmedium->hGlobal = NULL;
  72
  73         ATLASSERT(m_StgMedium.GetSize() == m_ArrFormatEtc.GetSize());
  74         for(int i=0; i < m_ArrFormatEtc.GetSize(); ++i)
  75         {
  76                 if(pformatetcIn->tymed & m_ArrFormatEtc[i]->tymed &&
  77                    pformatetcIn->dwAspect == m_ArrFormatEtc[i]->dwAspect &&
  78                    pformatetcIn->cfFormat == m_ArrFormatEtc[i]->cfFormat)
  79                 {
  80                         CopyMedium(pmedium, m_StgMedium[i], m_ArrFormatEtc[i]);
  81                         return S_OK;
  82                 }
  83         }
  84         return DV_E_FORMATETC;
  85 }
  86
  87 STDMETHODIMP CIDataObject::GetDataHere(
  88     /* [unique][in] */ FORMATETC __RPC_FAR * /*pformatetc*/,
  89     /* [out][in] */ STGMEDIUM __RPC_FAR * /*pmedium*/)
  90 {
  91         return E_NOTIMPL;
  92 }
  93
  94 STDMETHODIMP CIDataObject::QueryGetData(
  95    /* [unique][in] */ FORMATETC __RPC_FAR *pformatetc)
  96 {
  97         if(pformatetc == NULL)
  98                 return E_INVALIDARG;
  99
 100         //support others if needed DVASPECT_THUMBNAIL  //DVASPECT_ICON   //DVASPECT_DOCPRINT
 101         if (!(DVASPECT_CONTENT & pformatetc->dwAspect))
 102                 return (DV_E_DVASPECT);
 103         HRESULT  hr = DV_E_TYMED;
 104         for(int i = 0; i < m_ArrFormatEtc.GetSize(); ++i)
 105         {
 106            if(pformatetc->tymed & m_ArrFormatEtc[i]->tymed)
 107            {
 108                   if(pformatetc->cfFormat == m_ArrFormatEtc[i]->cfFormat)
 109                          return S_OK;
 110                   else
 111                          hr = DV_E_CLIPFORMAT;
 112            }
 113            else
 114                   hr = DV_E_TYMED;
 115         }
 116         return hr;
 117 }
 118
 119 STDMETHODIMP CIDataObject::GetCanonicalFormatEtc(
 120     /* [unique][in] */ FORMATETC __RPC_FAR * /*pformatectIn*/,
 121     /* [out] */ FORMATETC __RPC_FAR *pformatetcOut)
 122 {
 123         if (pformatetcOut == NULL)
 124                 return E_INVALIDARG;
 125         return DATA_S_SAMEFORMATETC;
 126 }
 127
 128 STDMETHODIMP CIDataObject::SetData(
 129     /* [unique][in] */ FORMATETC __RPC_FAR *pformatetc,
 130     /* [unique][in] */ STGMEDIUM __RPC_FAR *pmedium,
 131     /* [in] */ BOOL fRelease)
 132 {
 133         if(pformatetc == NULL || pmedium == NULL)
 134       return E_INVALIDARG;
 135
 136         ATLASSERT(pformatetc->tymed == pmedium->tymed);
 137         FORMATETC* fetc=new FORMATETC;
 138         STGMEDIUM* pStgMed = new STGMEDIUM;
 139
 140         if(fetc == NULL || pStgMed == NULL)
 141                 return E_OUTOFMEMORY;
 142
 143         SecureZeroMemory(fetc,sizeof(FORMATETC));
 144         SecureZeroMemory(pStgMed,sizeof(STGMEDIUM));
 145
 146         *fetc = *pformatetc;
 147         m_ArrFormatEtc.Add(fetc);
 148
 149     if(fRelease)
 150       *pStgMed = *pmedium;
 151     else
 152     {
 153                 CopyMedium(pStgMed, pmedium, pformatetc);
 154         }
 155         m_StgMedium.Add(pStgMed);
 156
 157     return S_OK;
 158 }
 159 void CIDataObject::CopyMedium(STGMEDIUM* pMedDest, STGMEDIUM* pMedSrc, FORMATETC* pFmtSrc)
 160 {
 161                 switch(pMedSrc->tymed)
 162                 {
 163                 case TYMED_HGLOBAL:
 164                         pMedDest->hGlobal = (HGLOBAL)OleDuplicateData(pMedSrc->hGlobal,pFmtSrc->cfFormat, NULL);
 165                         break;
 166                 case TYMED_GDI:
 167                         pMedDest->hBitmap = (HBITMAP)OleDuplicateData(pMedSrc->hBitmap,pFmtSrc->cfFormat, NULL);
 168                         break;
 169                 case TYMED_MFPICT:
 170                         pMedDest->hMetaFilePict = (HMETAFILEPICT)OleDuplicateData(pMedSrc->hMetaFilePict,pFmtSrc->cfFormat, NULL);
 171                         break;
 172                 case TYMED_ENHMF:
 173                         pMedDest->hEnhMetaFile = (HENHMETAFILE)OleDuplicateData(pMedSrc->hEnhMetaFile,pFmtSrc->cfFormat, NULL);
 174                         break;
 175                 case TYMED_FILE:
 176                         pMedSrc->lpszFileName = (LPOLESTR)OleDuplicateData(pMedSrc->lpszFileName,pFmtSrc->cfFormat, NULL);
 177                         break;
 178                 case TYMED_ISTREAM:
 179                         pMedDest->pstm = pMedSrc->pstm;
 180                         pMedSrc->pstm->AddRef();
 181                         break;
 182                 case TYMED_ISTORAGE:
 183                         pMedDest->pstg = pMedSrc->pstg;
 184                         pMedSrc->pstg->AddRef();
 185                         break;
 186                 case TYMED_NULL:
 187                 default:
 188                         break;
 189                 }
 190                 pMedDest->tymed = pMedSrc->tymed;
 191                 pMedDest->pUnkForRelease = NULL;
 192                 if(pMedSrc->pUnkForRelease != NULL)
 193                 {
 194                         pMedDest->pUnkForRelease = pMedSrc->pUnkForRelease;
 195                         pMedSrc->pUnkForRelease->AddRef();
 196                 }
 197 }
 198 STDMETHODIMP CIDataObject::EnumFormatEtc(
 199    /* [in] */ DWORD dwDirection,
 200    /* [out] */ IEnumFORMATETC __RPC_FAR *__RPC_FAR *ppenumFormatEtc)
 201 {
 202         if(ppenumFormatEtc == NULL)
 203       return E_POINTER;
 204
 205         *ppenumFormatEtc=NULL;
 206         switch (dwDirection)
 207     {
 208       case DATADIR_GET:
 209          *ppenumFormatEtc= new CEnumFormatEtc(m_ArrFormatEtc);
 210                  if(*ppenumFormatEtc == NULL)
 211                          return E_OUTOFMEMORY;
 212          (*ppenumFormatEtc)->AddRef();
 213          break;
 214
 215           case DATADIR_SET:
 216       default:
 217                  return E_NOTIMPL;
 218          break;
 219     }
 220
 221    return S_OK;
 222 }
 223
 224 STDMETHODIMP CIDataObject::DAdvise(
 225    /* [in] */ FORMATETC __RPC_FAR * /*pformatetc*/,
 226    /* [in] */ DWORD /*advf*/,
 227    /* [unique][in] */ IAdviseSink __RPC_FAR * /*pAdvSink*/,
 228    /* [out] */ DWORD __RPC_FAR * /*pdwConnection*/)
 229 {
 230         return OLE_E_ADVISENOTSUPPORTED;
 231 }
 232
 233 STDMETHODIMP CIDataObject::DUnadvise(
 234    /* [in] */ DWORD /*dwConnection*/)
 235 {
 236         return E_NOTIMPL;
 237 }
 238
 239 HRESULT STDMETHODCALLTYPE CIDataObject::EnumDAdvise(
 240    /* [out] */ IEnumSTATDATA __RPC_FAR *__RPC_FAR * /*ppenumAdvise*/)
 241 {
 242         return OLE_E_ADVISENOTSUPPORTED;
 243 }
 244
 245 //////////////////////////////////////////////////////////////////////
 246 // CIDropSource Class
 247 //////////////////////////////////////////////////////////////////////
 248
 249 STDMETHODIMP CIDropSource::QueryInterface(/* [in] */ REFIID riid,
 250                                                                                  /* [iid_is][out] */ void __RPC_FAR *__RPC_FAR *ppvObject)
 251 {
 252    *ppvObject = NULL;
 253    if (IID_IUnknown==riid || IID_IDropSource==riid)
 254        *ppvObject=this;
 255
 256     if (*ppvObject != NULL)
 257     {
 258        ((LPUNKNOWN)*ppvObject)->AddRef();
 259         return S_OK;
 260     }
 261     return E_NOINTERFACE;
 262 }
 263
 264 STDMETHODIMP_(ULONG) CIDropSource::AddRef( void)
 265 {
 266         return ++m_cRefCount;
 267 }
 268
 269 STDMETHODIMP_(ULONG) CIDropSource::Release( void)
 270 {
 271    long nTemp;
 272    nTemp = --m_cRefCount;
 273    ATLASSERT(nTemp >= 0);
 274    if(nTemp==0)
 275       delete this;
 276    return nTemp;
 277 }
 278
 279 STDMETHODIMP CIDropSource::QueryContinueDrag(
 280     /* [in] */ BOOL fEscapePressed,
 281     /* [in] */ DWORD grfKeyState)
 282 {
 283    if(fEscapePressed)
 284       return DRAGDROP_S_CANCEL;
 285    if(!(grfKeyState & (MK_LBUTTON|MK_RBUTTON)))
 286    {
 287           m_bDropped = true;
 288       return DRAGDROP_S_DROP;
 289    }
 290
 291    return S_OK;
 292
 293 }
 294
 295 STDMETHODIMP CIDropSource::GiveFeedback(
 296     /* [in] */ DWORD /*dwEffect*/)
 297 {
 298         return DRAGDROP_S_USEDEFAULTCURSORS;
 299 }
 300
 301 //////////////////////////////////////////////////////////////////////
 302 // CEnumFormatEtc Class
 303 //////////////////////////////////////////////////////////////////////
 304
 305 CEnumFormatEtc::CEnumFormatEtc(const CSimpleArray<FORMATETC>& ArrFE):
 306 m_cRefCount(0),m_iCur(0)
 307 {
 308    ATLTRACE("CEnumFormatEtc::CEnumFormatEtc()\n");
 309    for(int i = 0; i < ArrFE.GetSize(); ++i)
 310                 m_pFmtEtc.Add(ArrFE[i]);
 311 }
 312
 313 CEnumFormatEtc::CEnumFormatEtc(const CSimpleArray<FORMATETC*>& ArrFE):
 314 m_cRefCount(0),m_iCur(0)
 315 {
 316    for(int i = 0; i < ArrFE.GetSize(); ++i)
 317                 m_pFmtEtc.Add(*ArrFE[i]);
 318 }
 319
 320 STDMETHODIMP  CEnumFormatEtc::QueryInterface(REFIID refiid, void FAR* FAR* ppv)
 321 {
 322    *ppv = NULL;
 323    if (IID_IUnknown==refiid || IID_IEnumFORMATETC==refiid)
 324              *ppv=this;
 325
 326     if (*ppv != NULL)
 327     {
 328         ((LPUNKNOWN)*ppv)->AddRef();
 329         return S_OK;
 330     }
 331     return E_NOINTERFACE;
 332 }
 333
 334 STDMETHODIMP_(ULONG) CEnumFormatEtc::AddRef(void)
 335 {
 336    return ++m_cRefCount;
 337 }
 338
 339 STDMETHODIMP_(ULONG) CEnumFormatEtc::Release(void)
 340 {
 341    long nTemp = --m_cRefCount;
 342    ATLASSERT(nTemp >= 0);
 343    if(nTemp == 0)
 344      delete this;
 345
 346    return nTemp;
 347 }
 348
 349 STDMETHODIMP CEnumFormatEtc::Next( ULONG celt,LPFORMATETC lpFormatEtc, ULONG FAR *pceltFetched)
 350 {
 351    if(pceltFetched != NULL)
 352            *pceltFetched=0;
 353
 354    ULONG cReturn = celt;
 355
 356    if(celt <= 0 || lpFormatEtc == NULL || m_iCur >= m_pFmtEtc.GetSize())
 357       return S_FALSE;
 358
 359    if(pceltFetched == NULL && celt != 1) // pceltFetched can be NULL only for 1 item request
 360       return S_FALSE;
 361
 362         while (m_iCur < m_pFmtEtc.GetSize() && cReturn > 0)
 363         {
 364                 *lpFormatEtc++ = m_pFmtEtc[m_iCur++];
 365                 --cReturn;
 366         }
 367         if (pceltFetched != NULL)
 368                 *pceltFetched = celt - cReturn;
 369
 370     return (cReturn == 0) ? S_OK : S_FALSE;
 371 }
 372
 373 STDMETHODIMP CEnumFormatEtc::Skip(ULONG celt)
 374 {
 375         if((m_iCur + int(celt)) >= m_pFmtEtc.GetSize())
 376                 return S_FALSE;
 377         m_iCur += celt;
 378         return S_OK;
 379 }
 380
 381 STDMETHODIMP CEnumFormatEtc::Reset(void)
 382 {
 383    m_iCur = 0;
 384    return S_OK;
 385 }
 386
 387 STDMETHODIMP CEnumFormatEtc::Clone(IEnumFORMATETC FAR * FAR*ppCloneEnumFormatEtc)
 388 {
 389   if(ppCloneEnumFormatEtc == NULL)
 390       return E_POINTER;
 391
 392   CEnumFormatEtc *newEnum = new CEnumFormatEtc(m_pFmtEtc);
 393   if(newEnum ==NULL)
 394                 return E_OUTOFMEMORY;
 395   newEnum->AddRef();
 396   newEnum->m_iCur = m_iCur;
 397   *ppCloneEnumFormatEtc = newEnum;
 398   return S_OK;
 399 }
 400
 401 //////////////////////////////////////////////////////////////////////
 402 // CIDropTarget Class
 403 //////////////////////////////////////////////////////////////////////
 404 CIDropTarget::CIDropTarget(HWND hTargetWnd):
 405         m_hTargetWnd(hTargetWnd),
 406         m_cRefCount(0), m_bAllowDrop(false),
 407         m_pDropTargetHelper(NULL), m_pSupportedFrmt(NULL)
 408 {
 409         if(FAILED(CoCreateInstance(CLSID_DragDropHelper,NULL,CLSCTX_INPROC_SERVER,
 410                      IID_IDropTargetHelper,(LPVOID*)&m_pDropTargetHelper)))
 411                 m_pDropTargetHelper = NULL;
 412 }
 413
 414 CIDropTarget::~CIDropTarget()
 415 {
 416         if(m_pDropTargetHelper != NULL)
 417         {
 418                 m_pDropTargetHelper->Release();
 419                 m_pDropTargetHelper = NULL;
 420         }
 421 }
 422
 423 HRESULT STDMETHODCALLTYPE CIDropTarget::QueryInterface( /* [in] */ REFIID riid,
 424                                                 /* [iid_is][out] */ void __RPC_FAR *__RPC_FAR *ppvObject)
 425 {
 426    *ppvObject = NULL;
 427    if (IID_IUnknown==riid || IID_IDropTarget==riid)
 428                          *ppvObject=this;
 429
 430         if (*ppvObject != NULL)
 431         {
 432                 ((LPUNKNOWN)*ppvObject)->AddRef();
 433                 return S_OK;
 434         }
 435         return E_NOINTERFACE;
 436 }
 437
 438 ULONG STDMETHODCALLTYPE CIDropTarget::Release( void)
 439 {
 440    long nTemp;
 441    nTemp = --m_cRefCount;
 442    ATLASSERT(nTemp >= 0);
 443    if(nTemp==0)
 444           delete this;
 445    return nTemp;
 446 }
 447
 448 bool CIDropTarget::QueryDrop(DWORD grfKeyState, LPDWORD pdwEffect)
 449 {
 450         DWORD dwOKEffects = *pdwEffect;
 451
 452         if(!m_bAllowDrop)
 453         {
 454            *pdwEffect = DROPEFFECT_NONE;
 455            return false;
 456         }
 457         //CTRL+SHIFT  -- DROPEFFECT_LINK
 458         //CTRL        -- DROPEFFECT_COPY
 459         //SHIFT       -- DROPEFFECT_MOVE
 460         //no modifier -- DROPEFFECT_MOVE or whatever is allowed by src
 461         *pdwEffect = (grfKeyState & MK_CONTROL) ?
 462                                  ( (grfKeyState & MK_SHIFT) ? DROPEFFECT_LINK : DROPEFFECT_COPY ):
 463                                  ( (grfKeyState & MK_SHIFT) ? DROPEFFECT_MOVE : 0 );
 464         if(*pdwEffect == 0)
 465         {
 466            // No modifier keys used by user while dragging.
 467            if (DROPEFFECT_MOVE & dwOKEffects)
 468                   *pdwEffect = DROPEFFECT_MOVE;
 469            else if (DROPEFFECT_COPY & dwOKEffects)
 470                   *pdwEffect = DROPEFFECT_COPY;
 471            else if (DROPEFFECT_LINK & dwOKEffects)
 472                   *pdwEffect = DROPEFFECT_LINK;
 473            else
 474            {
 475                   *pdwEffect = DROPEFFECT_NONE;
 476            }
 477         }
 478         else
 479         {
 480            // Check if the drag source application allows the drop effect desired by user.
 481            // The drag source specifies this in DoDragDrop
 482            if(!(*pdwEffect & dwOKEffects))
 483                   *pdwEffect = DROPEFFECT_NONE;
 484         }
 485
 486         return (DROPEFFECT_NONE == *pdwEffect)?false:true;
 487 }
 488
 489 HRESULT STDMETHODCALLTYPE CIDropTarget::DragEnter(
 490     /* [unique][in] */ IDataObject __RPC_FAR *pDataObj,
 491     /* [in] */ DWORD grfKeyState,
 492     /* [in] */ POINTL pt,
 493     /* [out][in] */ DWORD __RPC_FAR *pdwEffect)
 494 {
 495         if(pDataObj == NULL)
 496                 return E_INVALIDARG;
 497
 498         if(m_pDropTargetHelper)
 499                 m_pDropTargetHelper->DragEnter(m_hTargetWnd, pDataObj, (LPPOINT)&pt, *pdwEffect);
 500         //IEnumFORMATETC* pEnum;
 501         //pDataObj->EnumFormatEtc(DATADIR_GET,&pEnum);
 502         //FORMATETC ftm;
 503         //for()
 504         //pEnum->Next(1,&ftm,0);
 505         //pEnum->Release();
 506         m_pSupportedFrmt = NULL;
 507         for(int i =0; i<m_formatetc.GetSize(); ++i)
 508         {
 509                 m_bAllowDrop = (pDataObj->QueryGetData(&m_formatetc[i]) == S_OK)?true:false;
 510                 if(m_bAllowDrop)
 511                 {
 512                         m_pSupportedFrmt = &m_formatetc[i];
 513                         break;
 514                 }
 515         }
 516
 517         QueryDrop(grfKeyState, pdwEffect);
 518         return S_OK;
 519 }
 520
 521 HRESULT STDMETHODCALLTYPE CIDropTarget::DragOver(
 522         /* [in] */ DWORD grfKeyState,
 523         /* [in] */ POINTL pt,
 524         /* [out][in] */ DWORD __RPC_FAR *pdwEffect)
 525 {
 526         if(m_pDropTargetHelper)
 527                 m_pDropTargetHelper->DragOver((LPPOINT)&pt, *pdwEffect);
 528         QueryDrop(grfKeyState, pdwEffect);
 529         return S_OK;
 530 }
 531
 532 HRESULT STDMETHODCALLTYPE CIDropTarget::DragLeave( void)
 533 {
 534         if(m_pDropTargetHelper)
 535                 m_pDropTargetHelper->DragLeave();
 536
 537         m_bAllowDrop = false;
 538         m_pSupportedFrmt = NULL;
 539         return S_OK;
 540 }
 541
 542 HRESULT STDMETHODCALLTYPE CIDropTarget::Drop(
 543         /* [unique][in] */ IDataObject __RPC_FAR *pDataObj,
 544     /* [in] */ DWORD grfKeyState, /* [in] */ POINTL pt,
 545         /* [out][in] */ DWORD __RPC_FAR *pdwEffect)
 546 {
 547         if (pDataObj == NULL)
 548                 return E_INVALIDARG;
 549
 550         if(m_pDropTargetHelper)
 551                 m_pDropTargetHelper->Drop(pDataObj, (LPPOINT)&pt, *pdwEffect);
 552
 553         if(QueryDrop(grfKeyState, pdwEffect))
 554         {
 555                 if(m_bAllowDrop && m_pSupportedFrmt != NULL)
 556                 {
 557                         STGMEDIUM medium;
 558                         if(pDataObj->GetData(m_pSupportedFrmt, &medium) == S_OK)
 559                         {
 560                                 if(OnDrop(m_pSupportedFrmt, medium, pdwEffect, pt)) //does derive class wants us to free medium?
 561                                         ReleaseStgMedium(&medium);
 562                         }
 563                 }
 564         }
 565         m_bAllowDrop=false;
 566         *pdwEffect = DROPEFFECT_NONE;
 567         m_pSupportedFrmt = NULL;
 568         return S_OK;
 569 }
 570
 571 //////////////////////////////////////////////////////////////////////
 572 // CIDragSourceHelper Class
 573 //////////////////////////////////////////////////////////////////////