#if wxUSE_DRAG_AND_DROP
#include "wx/dataobj.h"
+#include "wx/cursor.h"
// ----------------------------------------------------------------------------
// constants
wxDragCancel // the operation was cancelled by user (not an error)
};
+inline WXDLLEXPORT bool wxIsDragResultOk(wxDragResult res)
+{
+ return res == wxDragCopy || res == wxDragMove;
+}
+
// ----------------------------------------------------------------------------
// wxDropSource is the object you need to create (and call DoDragDrop on it)
// to initiate a drag-and-drop operation
class WXDLLEXPORT wxDropSourceBase
{
public:
- wxDropSourceBase() { m_data = (wxDataObject *)NULL; }
+ wxDropSourceBase(const wxCursor &cursorCopy = wxNullCursor,
+ const wxCursor &cursorMove = wxNullCursor,
+ const wxCursor &cursorStop = wxNullCursor)
+ : m_cursorCopy(cursorCopy),
+ m_cursorMove(cursorMove),
+ m_cursorStop(cursorStop)
+ { m_data = (wxDataObject *)NULL; }
virtual ~wxDropSourceBase() { }
// set the data which is transfered by drag and drop
- void SetData(wxDataObject& data) { delete m_data; m_data = &data; }
+ void SetData(wxDataObject& data)
+ { m_data = &data; }
+
+ wxDataObject *GetDataObject()
+ { return m_data; }
+
+ // set the icon corresponding to given drag result
+ void SetCursor(wxDragResult res, const wxCursor& cursor)
+ {
+ if ( res == wxDragCopy )
+ m_cursorCopy = cursor;
+ else if ( res == wxDragMove )
+ m_cursorMove = cursor;
+ else
+ m_cursorStop = cursor;
+ }
// start drag action, see enum wxDragResult for return value description
//
// if bAllowMove is TRUE, data can be moved, if not - only copied
- virtual wxDragResult DoDragDrop( bool bAllowMove = FALSE );
+ virtual wxDragResult DoDragDrop(bool bAllowMove = FALSE) = 0;
// override to give feedback depending on the current operation result
- // "effect"
- virtual bool GiveFeedback( wxDragResult WXUNUSED(effect),
- bool WXUNUSED(bScrolling) )
+ // "effect" and return TRUE if you did something, FALSE to let the library
+ // give the default feedback
+ virtual bool GiveFeedback(wxDragResult WXUNUSED(effect)) { return FALSE; }
+
+protected:
+ const wxCursor& GetCursor(wxDragResult res) const
{
- return TRUE;
+ if ( res == wxDragCopy )
+ return m_cursorCopy;
+ else if ( res == wxDragMove )
+ return m_cursorMove;
+ else
+ return m_cursorStop;
}
-protected:
wxDataObject *m_data;
+
+ // the cursors to use for feedback
+ wxCursor m_cursorCopy, m_cursorMove, m_cursorStop;
};
// ----------------------------------------------------------------------------
// wxDropTarget should be associated with a window if it wants to be able to
-// receive data via drag and drop
+// receive data via drag and drop.
+//
+// To use this class, you should derive from wxDropTarget and implement
+// OnData() pure virtual method. You may also wish to override OnDrop() if you
+// want to accept the data only inside some region of the window (this may
+// avoid having to copy the data to this application which happens only when
+// OnData() is called)
// ----------------------------------------------------------------------------
class WXDLLEXPORT wxDropTargetBase
// ctor takes a pointer to heap-allocated wxDataObject which will be owned
// by wxDropTarget and deleted by it automatically. If you don't give it
// here, you can use SetDataObject() later.
- wxDropTargetBase(wxDataObject *dataObject = NULL)
+ wxDropTargetBase(wxDataObject *dataObject = (wxDataObject*)NULL)
{ m_dataObject = dataObject; }
// dtor deletes our data object
virtual ~wxDropTargetBase()
wxDataObject *GetDataObject() const
{ return m_dataObject; }
void SetDataObject(wxDataObject *dataObject)
- { delete m_dataObject; m_dataObject = dataObject; }
+ { if (m_dataObject) delete m_dataObject;
+ m_dataObject = dataObject; }
- // called when mouse enters/leaves the window: might be used to give
- // some visual feedback to the user
- virtual void OnEnter() { }
+ // these functions are called when data is moved over position (x, y) and
+ // may return either wxDragCopy, wxDragMove or wxDragNone depending on
+ // what would happen if the data were dropped here.
+ //
+ // the last parameter is what would happen by default and is determined by
+ // the platform-specific logic (for example, under Windows it's wxDragCopy
+ // if Ctrl key is pressed and wxDragMove otherwise) except that it will
+ // always be wxDragNone if the carried data is in an unsupported format.
+
+ // called when the mouse enters the window (only once until OnLeave())
+ virtual wxDragResult OnEnter(wxCoord x, wxCoord y, wxDragResult def)
+ { return OnDragOver(x, y, def); }
+
+ // called when the mouse moves in the window - shouldn't take long to
+ // execute or otherwise mouse movement would be too slow
+ virtual wxDragResult OnDragOver(wxCoord WXUNUSED(x), wxCoord WXUNUSED(y),
+ wxDragResult def)
+ { return def; }
+
+ // called when mouse leaves the window: might be used to remove the
+ // feedback which was given in OnEnter()
virtual void OnLeave() { }
// this function is called when data is dropped at position (x, y) - if it
// called after OnDrop() returns TRUE: you will usually just call
// GetData() from here and, probably, also refresh something to update the
- // new data
- virtual bool OnData() = 0;
+ // new data and, finally, return the code indicating how did the operation
+ // complete (returning default value in case of success and wxDragError on
+ // failure is usually ok)
+ virtual wxDragResult OnData(wxCoord x, wxCoord y, wxDragResult def) = 0;
// may be called *only* from inside OnData() and will fill m_dataObject
// with the data from the drop source if it returns TRUE
// ----------------------------------------------------------------------------
#if defined(__WXMSW__)
- #include "wx/dataobj.h"
#include "wx/msw/ole/dropsrc.h"
#include "wx/msw/ole/droptgt.h"
#elif defined(__WXMOTIF__)
#include "wx/stubs/dnd.h"
#endif
+// ----------------------------------------------------------------------------
+// standard wxDropTarget implementations (implemented in common/dobjcmn.cpp)
+// ----------------------------------------------------------------------------
+
+// A simple wxDropTarget derived class for text data: you only need to
+// override OnDropText() to get something working
+class WXDLLEXPORT wxTextDropTarget : public wxDropTarget
+{
+public:
+ wxTextDropTarget();
+
+ virtual bool OnDropText(wxCoord x, wxCoord y, const wxString& text) = 0;
+
+ virtual wxDragResult OnData(wxCoord x, wxCoord y, wxDragResult def);
+};
+
+// A drop target which accepts files (dragged from File Manager or Explorer)
+class WXDLLEXPORT wxFileDropTarget : public wxDropTarget
+{
+public:
+ wxFileDropTarget();
+
+ // parameters are the number of files and the array of file names
+ virtual bool OnDropFiles(wxCoord x, wxCoord y,
+ const wxArrayString& filenames) = 0;
+
+ virtual wxDragResult OnData(wxCoord x, wxCoord y, wxDragResult def);
+};
+
#endif // wxUSE_DRAG_AND_DROP
#endif // _WX_DND_H_BASE_
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