include/wx/msw/ole/droptgt.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        ole/droptgt.h
   3 // Purpose:     declaration of the wxDropTarget class
   4 // Author:      Vadim Zeitlin
   5 // Modified by:
   6 // Created:     06.03.98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) 1998 Vadim Zeitlin <zeitlin@dptmaths.ens-cachan.fr>
   9 // Licence:     wxWindows license
  10 ///////////////////////////////////////////////////////////////////////////////
  11
  12 // ============================================================================
  13 // prolog
  14 // ============================================================================
  15 #ifndef   _OLEDROPTGT_H
  16 #define   _OLEDROPTGT_H
  17
  18 #ifdef __GNUG__
  19 #pragma interface "droptgt.h"
  20 #endif
  21
  22 #if !USE_DRAG_AND_DROP
  23   #error  "You should #define USE_DRAG_AND_DROP to 1 to compile this file!"
  24 #endif  //WX_DRAG_DROP
  25
  26 // ----------------------------------------------------------------------------
  27 // forward declarations
  28 // ----------------------------------------------------------------------------
  29 class  wxIDropTarget;
  30 struct IDataObject;
  31
  32 typedef unsigned short wxDataFormat;
  33
  34 // ----------------------------------------------------------------------------
  35 // An instance of the class wxDropTarget may be associated with any wxWindow
  36 // derived object via SetDropTarget() function. If this is done, the virtual
  37 // methods of wxDropTarget are called when something is dropped on the window.
  38 //
  39 // Note that wxDropTarget is an abstract base class (ABC) and you should derive
  40 // your own class from it implementing pure virtual function in order to use it
  41 // (all of them, including protected ones which are called by the class itself)
  42 // ----------------------------------------------------------------------------
  43 class WXDLLEXPORT wxDropTarget
  44 {
  45 public:
  46   // ctor & dtor
  47   wxDropTarget();
  48   virtual ~wxDropTarget();
  49
  50   // normally called by wxWindow on window creation/destruction, but might be
  51   // called `manually' as well. Register() returns true on success.
  52   bool Register(WXHWND hwnd);
  53   void Revoke(WXHWND hwnd);
  54
  55   // do we accept this kind of data?
  56   virtual bool IsAcceptedData(IDataObject *pIDataSource) const;
  57
  58   // called when mouse enters/leaves the window: might be used to give
  59   // some visual feedback to the user
  60   virtual void OnEnter() { }
  61   virtual void OnLeave() { }
  62
  63   // this function is called when data is dropped.
  64   // (x, y) are the coordinates of the drop
  65   virtual bool OnDrop(long x, long y, const void *pData) = 0;
  66
  67 protected:
  68   // Override these to indicate what kind of data you support: the first
  69   // format to which data can be converted is used. The classes below show
  70   // how it can be done in the simplest cases.
  71     // how many different (clipboard) formats do you support?
  72   virtual size_t GetFormatCount() const = 0;
  73     // return the n-th supported format
  74   virtual wxDataFormat GetFormat(size_t n) const = 0;
  75
  76 private:
  77   wxIDropTarget    *m_pIDropTarget; // the pointer to COM interface
  78 };
  79
  80 // ----------------------------------------------------------------------------
  81 // A simple wxDropTarget derived class for text data: you only need to
  82 // override OnDropText() to get something working
  83 // ----------------------------------------------------------------------------
  84 class WXDLLEXPORT wxTextDropTarget : public wxDropTarget
  85 {
  86 public:
  87   virtual bool OnDrop(long x, long y, const void *pData);
  88   virtual bool OnDropText(long x, long y, const char *psz) = 0;
  89
  90 protected:
  91   virtual size_t GetFormatCount() const;
  92   virtual wxDataFormat GetFormat(size_t n) const;
  93 };
  94
  95 // ----------------------------------------------------------------------------
  96 // A drop target which accepts files (dragged from File Manager or Explorer)
  97 // ----------------------------------------------------------------------------
  98 class WXDLLEXPORT wxFileDropTarget : public wxDropTarget
  99 {
 100 public:
 101   virtual bool OnDrop(long x, long y, const void *pData);
 102
 103   // params: the number of files and the array of file names
 104   virtual bool OnDropFiles(long x, long y,
 105                            size_t nFiles, const char * const aszFiles[]) = 0;
 106
 107 protected:
 108   virtual size_t GetFormatCount() const;
 109   virtual wxDataFormat GetFormat(size_t n) const;
 110 };
 111
 112 // ============================================================================
 113 #endif  //_OLEDROPTGT_H