avoiding crash for pure modifier events

[wxWidgets.git] / include / wx / motif / dnd.h

///////////////////////////////////////////////////////////////////////////////
// Name:        wx/motif/dnd.h
// Purpose:     declaration of wxDropTarget, wxDropSource classes
// Author:      Julian Smart
// RCS-ID:      $Id$
// Copyright:   (c) 1998 Vadim Zeitlin, Robert Roebling, Julian Smart
// Licence:     wxWindows licence
///////////////////////////////////////////////////////////////////////////////

#ifndef _WX_DND_H_
#define _WX_DND_H_

#include "wx/defs.h"

#if wxUSE_DRAG_AND_DROP

#include "wx/object.h"
#include "wx/string.h"
#include "wx/dataobj.h"
#include "wx/cursor.h"

//-------------------------------------------------------------------------
// classes
//-------------------------------------------------------------------------

class WXDLLIMPEXP_FWD_CORE wxWindow;

class WXDLLIMPEXP_FWD_CORE wxDropTarget;
class WXDLLIMPEXP_FWD_CORE wxTextDropTarget;
class WXDLLIMPEXP_FWD_CORE wxFileDropTarget;
class WXDLLIMPEXP_FWD_CORE wxPrivateDropTarget;

class WXDLLIMPEXP_FWD_CORE wxDropSource;

//-------------------------------------------------------------------------
// wxDropTarget
//-------------------------------------------------------------------------

class WXDLLIMPEXP_CORE wxDropTarget: public wxObject
{
public:

    wxDropTarget();
    virtual ~wxDropTarget();

    virtual void OnEnter() { }
    virtual void OnLeave() { }
    virtual bool OnDrop( long x, long y, const void *data, size_t size ) = 0;

    // Override these to indicate what kind of data you support:

    virtual size_t GetFormatCount() const = 0;
    virtual wxDataFormat GetFormat(size_t n) const = 0;

    // implementation
};

//-------------------------------------------------------------------------
// wxTextDropTarget
//-------------------------------------------------------------------------

class WXDLLIMPEXP_CORE wxTextDropTarget: public wxDropTarget
{
public:

    wxTextDropTarget() {};
    virtual bool OnDrop( long x, long y, const void *data, size_t size );
    virtual bool OnDropText( long x, long y, const char *psz );

protected:

    virtual size_t GetFormatCount() const;
    virtual wxDataFormat GetFormat(size_t n) const;
};

//-------------------------------------------------------------------------
// wxPrivateDropTarget
//-------------------------------------------------------------------------

class WXDLLIMPEXP_CORE wxPrivateDropTarget: public wxDropTarget
{
public:

    wxPrivateDropTarget();

    // you have to override OnDrop to get at the data

    // the string ID identifies the format of clipboard or DnD data. a word
    // processor would e.g. add a wxTextDataObject and a wxPrivateDataObject
    // to the clipboard - the latter with the Id "WXWORD_FORMAT".

    void SetId( const wxString& id )
    { m_id = id; }

    wxString GetId()
    { return m_id; }

private:

    virtual size_t GetFormatCount() const;
    virtual wxDataFormat GetFormat(size_t n) const;

    wxString   m_id;
};

// ----------------------------------------------------------------------------
// A drop target which accepts files (dragged from File Manager or Explorer)
// ----------------------------------------------------------------------------

class WXDLLIMPEXP_CORE wxFileDropTarget: public wxDropTarget
{
public:

    wxFileDropTarget() {};

    virtual bool OnDrop( long x, long y, const void *data, size_t size );
    virtual bool OnDropFiles( long x, long y,
        size_t nFiles, const char * const aszFiles[] );

protected:

    virtual size_t GetFormatCount() const;
    virtual wxDataFormat GetFormat(size_t n) const;
};

//-------------------------------------------------------------------------
// wxDropSource
//-------------------------------------------------------------------------

enum wxDragResult
{
    wxDragError,    // error prevented the d&d operation from completing
        wxDragNone,     // drag target didn't accept the data
        wxDragCopy,     // the data was successfully copied
        wxDragMove,     // the data was successfully moved
        wxDragCancel    // the operation was cancelled by user (not an error)
};

class WXDLLIMPEXP_CORE wxDropSource: public wxObject
{
public:

    wxDropSource( wxWindow *win );
    wxDropSource( wxDataObject &data, wxWindow *win );

    virtual ~wxDropSource(void);

    void SetData( wxDataObject &data  );
    wxDragResult DoDragDrop(int flags = wxDrag_CopyOnly);

    virtual bool GiveFeedback( wxDragResult WXUNUSED(effect), bool WXUNUSED(bScrolling) ) { return true; };

    // implementation
#if 0
    void RegisterWindow(void);
    void UnregisterWindow(void);

    wxWindow      *m_window;
    wxDragResult   m_retValue;
    wxDataObject  *m_data;

    wxCursor      m_defaultCursor;
    wxCursor      m_goaheadCursor;
#endif
};

#endif

// wxUSE_DRAG_AND_DROP

#endif
//_WX_DND_H_