widget/windows/nsNativeDragSource.h

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5 #ifndef _nsNativeDragSource_h_
   6 #define _nsNativeDragSource_h_
   7
   8 #include "nscore.h"
   9 #include <ole2.h>
  10 #include <oleidl.h>
  11 #include "mozilla/Attributes.h"
  12 #include "mozilla/RefPtr.h"
  13
  14 namespace mozilla {
  15 namespace dom {
  16 class DataTransfer;
  17 }  // namespace dom
  18 }  // namespace mozilla
  19
  20 // class nsIDragSource;
  21
  22 /*
  23  * nsNativeDragSource implements the IDropSource interface and gets
  24  * most of its behavior from the associated adapter (m_dragDrop).
  25  */
  26 class nsNativeDragSource final : public IDropSource {
  27  public:
  28   // construct an nsNativeDragSource referencing adapter
  29   // nsNativeDragSource(nsIDragSource * adapter);
  30   explicit nsNativeDragSource(mozilla::dom::DataTransfer* aDataTransfer);
  31   ~nsNativeDragSource();
  32
  33   // IUnknown methods - see iunknown.h for documentation
  34
  35   STDMETHODIMP QueryInterface(REFIID, void**);
  36   STDMETHODIMP_(ULONG) AddRef();
  37   STDMETHODIMP_(ULONG) Release();
  38
  39   // IDropSource methods - see idropsrc.h for documentation
  40
  41   // Return DRAGDROP_S_USEDEFAULTCURSORS if this object lets OLE provide
  42   // default cursors, otherwise return NOERROR. This method gets called in
  43   // response to changes that the target makes to dEffect (DragEnter,
  44   // DragOver).
  45   STDMETHODIMP GiveFeedback(DWORD dEffect);
  46
  47   // This method gets called if there is any change in the mouse or key
  48   // state.  Return DRAGDROP_S_CANCEL to stop the drag, DRAGDROP_S_DROP
  49   // to execute the drop, otherwise NOERROR.
  50   STDMETHODIMP QueryContinueDrag(BOOL fESC, DWORD grfKeyState);
  51
  52   bool UserCancelled() { return mUserCancelled; }
  53
  54  protected:
  55   // Reference count
  56   ULONG m_cRef;
  57
  58   // Data object, hold information about cursor state
  59   RefPtr<mozilla::dom::DataTransfer> mDataTransfer;
  60
  61   // Custom drag cursor
  62   HCURSOR m_hCursor;
  63
  64   // true if the user cancelled the drag by pressing escape
  65   bool mUserCancelled;
  66 };
  67
  68 #endif  // _nsNativeDragSource_h_