include/wx/gtk/dnd.h

   1 ///////////////////////////////////////////////////////////////////////////////
   2 // Name:        dnd.h
   3 // Purpose:     declaration of the wxDropTarget class
   4 // Author:      Robert Roebling
   5 // RCS-ID:      $Id$
   6 // Copyright:   (c) 1998 Vadim Zeitlin, Robert Roebling
   7 // Licence:     wxWindows license
   8 ///////////////////////////////////////////////////////////////////////////////
   9
  10
  11 #ifndef __GTKDNDH__
  12 #define __GTKDNDH__
  13
  14 #ifdef __GNUG__
  15 #pragma interface
  16 #endif
  17
  18 #include "wx/defs.h"
  19 #include "wx/object.h"
  20 #include "wx/string.h"
  21 #include "wx/cursor.h"
  22
  23 //-------------------------------------------------------------------------
  24 // classes
  25 //-------------------------------------------------------------------------
  26
  27 class wxWindow;
  28
  29 class wxDataObject;
  30 class wxTextDataObject;
  31 class wxFileDataObject;
  32
  33 class wxDropTarget;
  34 class wxTextDropTarget;
  35 class wxFileDropTarget;
  36
  37 class wxDropSource;
  38
  39 //-------------------------------------------------------------------------
  40 // wxDataObject
  41 //-------------------------------------------------------------------------
  42
  43 class wxDataObject: public wxObject
  44 {
  45 public:
  46   // all data formats (values are the same as in windows.h, do not change!)
  47   enum StdFormat
  48   {
  49     Invalid,
  50     Text,
  51     Bitmap,
  52     MetafilePict,
  53     Sylk,
  54     Dif,
  55     Tiff,
  56     OemText,
  57     Dib,
  58     Palette,
  59     Pendata,
  60     Riff,
  61     Wave,
  62     UnicodeText,
  63     EnhMetafile,
  64     Hdrop,
  65     Locale,
  66     Max
  67   };
  68
  69   // function to return symbolic name of clipboard format (debug messages)
  70   static const char *GetFormatName(wxDataFormat format);
  71
  72   // ctor & dtor
  73   wxDataObject() {};
  74   ~wxDataObject() {};
  75
  76   // pure virtuals to override
  77     // get the best suited format for our data
  78   virtual wxDataFormat GetPreferredFormat() const = 0;
  79     // decide if we support this format (should be one of values of
  80     // StdFormat enumerations or a user-defined format)
  81   virtual bool IsSupportedFormat(wxDataFormat format) const = 0;
  82     // get the (total) size of data
  83   virtual size_t GetDataSize() const = 0;
  84     // copy raw data to provided pointer
  85   virtual void GetDataHere(void *pBuf) const = 0;
  86
  87 };
  88
  89 // ----------------------------------------------------------------------------
  90 // wxTextDataObject is a specialization of wxDataObject for text data
  91 // ----------------------------------------------------------------------------
  92
  93 class wxTextDataObject : public wxDataObject
  94 {
  95 public:
  96   // ctors
  97   wxTextDataObject() { }
  98   wxTextDataObject(const wxString& strText) : m_strText(strText) { }
  99   void Init(const wxString& strText) { m_strText = strText; }
 100
 101   // implement base class pure virtuals
 102   virtual wxDataFormat GetPreferredFormat() const
 103     { return wxDF_TEXT; }
 104   virtual bool IsSupportedFormat(wxDataFormat format) const
 105     { return format == wxDF_TEXT; }
 106   virtual size_t GetDataSize() const
 107     { return m_strText.Len() + 1; } // +1 for trailing '\0'of course
 108   virtual void GetDataHere(void *pBuf) const
 109     { memcpy(pBuf, m_strText.c_str(), GetDataSize()); }
 110
 111 private:
 112   wxString  m_strText;
 113
 114 };
 115
 116 // ----------------------------------------------------------------------------
 117 // wxFileDataObject is a specialization of wxDataObject for file names
 118 // ----------------------------------------------------------------------------
 119
 120 class wxFileDataObject : public wxDataObject
 121 {
 122 public:
 123
 124   wxFileDataObject(void) { }
 125   void AddFile( const wxString &file )
 126     { m_files += file; m_files += '\0'; }
 127
 128   // implement base class pure virtuals
 129   virtual wxDataFormat GetPreferredFormat() const
 130     { return wxDF_FILENAME; }
 131   virtual bool IsSupportedFormat(wxDataFormat format) const
 132     { return format == wxDF_FILENAME; }
 133   virtual size_t GetDataSize() const
 134     { return m_files.Len(); } // no trailing '\0'
 135   virtual void GetDataHere(void *pBuf) const
 136     { memcpy(pBuf, m_files.c_str(), GetDataSize()); }
 137
 138 private:
 139   wxString  m_files;
 140
 141 };
 142 //-------------------------------------------------------------------------
 143 // wxDropTarget
 144 //-------------------------------------------------------------------------
 145
 146 class wxDropTarget: public wxObject
 147 {
 148   public:
 149
 150     wxDropTarget();
 151     ~wxDropTarget();
 152
 153     virtual void OnEnter() { }
 154     virtual void OnLeave() { }
 155     virtual bool OnDrop( long x, long y, const void *pData ) = 0;
 156
 157   // implementation
 158
 159     int  m_size;
 160
 161     // Override these to indicate what kind of data you support:
 162
 163     virtual size_t GetFormatCount() const = 0;
 164     virtual wxDataFormat GetFormat(size_t n) const = 0;
 165
 166     void Drop( GdkEventDropDataAvailable *event, int x, int y );
 167     void RegisterWidget( GtkWidget *widget );
 168     void UnregisterWidget( GtkWidget *widget );
 169 };
 170
 171 //-------------------------------------------------------------------------
 172 // wxTextDropTarget
 173 //-------------------------------------------------------------------------
 174
 175 class wxTextDropTarget: public wxDropTarget
 176 {
 177   public:
 178
 179     wxTextDropTarget() {};
 180     virtual bool OnDrop( long x, long y, const void *pData );
 181     virtual bool OnDropText( long x, long y, const char *psz );
 182
 183   protected:
 184
 185     virtual size_t GetFormatCount() const;
 186     virtual wxDataFormat GetFormat(size_t n) const;
 187 };
 188
 189 // ----------------------------------------------------------------------------
 190 // A drop target which accepts files (dragged from File Manager or Explorer)
 191 // ----------------------------------------------------------------------------
 192
 193 class wxFileDropTarget: public wxDropTarget
 194 {
 195   public:
 196
 197     wxFileDropTarget() {};
 198
 199     virtual bool OnDrop(long x, long y, const void *pData);
 200     virtual bool OnDropFiles( long x, long y,
 201                               size_t nFiles, const char * const aszFiles[]);
 202
 203   protected:
 204
 205     virtual size_t GetFormatCount() const;
 206     virtual wxDataFormat GetFormat(size_t n) const;
 207 };
 208
 209 //-------------------------------------------------------------------------
 210 // wxDropSource
 211 //-------------------------------------------------------------------------
 212
 213   enum wxDragResult
 214   {
 215     wxDragError,    // error prevented the d&d operation from completing
 216     wxDragNone,     // drag target didn't accept the data
 217     wxDragCopy,     // the data was successfully copied
 218     wxDragMove,     // the data was successfully moved
 219     wxDragCancel    // the operation was cancelled by user (not an error)
 220   };
 221
 222 class wxDropSource: public wxObject
 223 {
 224   public:
 225
 226     wxDropSource( wxWindow *win );
 227     wxDropSource( wxDataObject &data, wxWindow *win );
 228
 229     ~wxDropSource(void);
 230
 231     void SetData( wxDataObject &data  );
 232     wxDragResult DoDragDrop( bool bAllowMove = FALSE );
 233
 234     virtual bool GiveFeedback( wxDragResult WXUNUSED(effect), bool WXUNUSED(bScrolling) ) { return TRUE; };
 235
 236   protected:
 237
 238     friend void gtk_drag_callback( GtkWidget *widget, GdkEvent *event, wxDropSource *source );
 239
 240     void RegisterWindow(void);
 241     void UnregisterWindow(void);
 242
 243     GtkWidget     *m_widget;
 244     wxWindow      *m_window;
 245     wxDragResult   m_retValue;
 246     wxDataObject  *m_data;
 247
 248     wxCursor      m_defaultCursor;
 249     wxCursor      m_goaheadCursor;
 250 };
 251
 252 #endif
 253        //__GTKDNDH__
 254