Simplified event based Drag API for wxDataViewCtrl

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@58238 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/dataview.h

@@ -744,8 +744,7 @@ public:
         m_value(wxNullVariant),
         m_column(NULL),
         m_pos(-1,-1),
-        m_isDraggable(false),
+        m_dataObject(NULL)
-        m_dragDataSize(-1)
         { }
 
     wxDataViewEvent(const wxDataViewEvent& event)
@@ -756,8 +755,7 @@ public:
         m_value(event.m_value),
         m_column(event.m_column),
         m_pos(m_pos),
-        m_isDraggable(event.m_isDraggable),
+        m_dataObject(event.m_dataObject)
-        m_dragDataSize(event.m_dragDataSize)
         { }
 
     wxDataViewItem GetItem() const { return m_item; }
@@ -780,15 +778,9 @@ public:
     wxPoint GetPosition() const { return m_pos; }
     void SetPosition( int x, int y ) { m_pos.x = x; m_pos.y = y; }
 
-    // For Drag operations
+    // For DnD operations
-    bool IsDraggable() const { return m_isDraggable; }
+    void SetDataObject( wxDataObject *obj ) { m_dataObject = obj; }
-    void SetDraggable( bool can_drag = true ) { m_isDraggable = can_drag; }
+    wxDataObject *GetDataObject() { return m_dataObject; }
-    int GetDragDataSize() const { return m_dragDataSize; }
-    void SetDragDataSize( int size ) { m_dragDataSize = size; }
-    void* GetDragDataBuffer() const { return m_dragDataBuffer; }
-    void SetDragDataBuffer( void *buffer ) { m_dragDataBuffer = buffer; }
-    wxDataFormat GetDataFormat() const { return m_dataFormat; }
-    void SetDataFormat( const wxDataFormat &format ) { m_dataFormat = format; }
 
     virtual wxEvent *Clone() const { return new wxDataViewEvent(*this); }
 
@@ -799,11 +791,7 @@ protected:
     wxVariant           m_value;
     wxDataViewColumn   *m_column;
     wxPoint             m_pos;
-    
+    wxDataObject       *m_dataObject;
-    bool                m_isDraggable;
-    int                 m_dragDataSize;
-    void               *m_dragDataBuffer;
-    wxDataFormat        m_dataFormat;
 
 private:
     DECLARE_DYNAMIC_CLASS_NO_ASSIGN(wxDataViewEvent)
@@ -827,9 +815,7 @@ wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_COLUMN_HEADER_
 wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_COLUMN_SORTED, wxDataViewEvent )
 wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_COLUMN_REORDERED, wxDataViewEvent )
 
-wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_ITEM_DRAGGABLE, wxDataViewEvent )
+wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_ITEM_BEGIN_DRAG, wxDataViewEvent )
-wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_ITEM_GET_DRAG_DATA_SIZE, wxDataViewEvent )
-wxDECLARE_EXPORTED_EVENT( WXDLLIMPEXP_ADV, wxEVT_COMMAND_DATAVIEW_ITEM_GET_DRAG_DATA, wxDataViewEvent )
 
 typedef void (wxEvtHandler::*wxDataViewEventFunction)(wxDataViewEvent&);
 
@@ -857,9 +843,7 @@ typedef void (wxEvtHandler::*wxDataViewEventFunction)(wxDataViewEvent&);
 #define EVT_DATAVIEW_COLUMN_SORTED(id, fn) wx__DECLARE_DATAVIEWEVT(COLUMN_SORTED, id, fn)
 #define EVT_DATAVIEW_COLUMN_REORDERED(id, fn) wx__DECLARE_DATAVIEWEVT(COLUMN_REORDERED, id, fn)
 
-#define EVT_DATAVIEW_ITEM_DRAGGABLE(id, fn) wx__DECLARE_DATAVIEWEVT(ITEM_DRAGGABLE, id, fn)
+#define EVT_DATAVIEW_ITEM_BEGIN_DRAG(id, fn) wx__DECLARE_DATAVIEWEVT(ITEM_BEGIN_DRAG, id, fn)
-#define EVT_DATAVIEW_ITEM_GET_DRAG_DATA_SIZE(id, fn) wx__DECLARE_DATAVIEWEVT(ITEM_GET_DRAG_DATA_SIZE, id, fn)
-#define EVT_DATAVIEW_ITEM_GET_DRAG_DATA(id, fn) wx__DECLARE_DATAVIEWEVT(ITEM_GET_DRAG_DATA, id, fn)
 
 #ifdef wxHAS_GENERIC_DATAVIEWCTRL
     // this symbol doesn't follow the convention for wxUSE_XXX symbols which

interface/wx/dataview.h

@@ -554,6 +554,8 @@ public:
            Process a wxEVT_COMMAND_DATAVIEW_COLUMN_SORTED event.
     @event{EVT_DATAVIEW_COLUMN_REORDERED(id, func)}
            Process a wxEVT_COMMAND_DATAVIEW_COLUMN_REORDERED event.
+    @event{EVT_DATAVIEW_ITEM_BEGIN_DRAG(id, func)}
+           Process a wxEVT_COMMAND_DATAVIEW_ITEM_BEGIN_DRAG event.
     @endEventTable
 
     @library{wxadv}
@@ -2197,14 +2199,11 @@ public:
 class wxDataViewEvent : public wxNotifyEvent
 {
 public:
-    //@{
     /**
         Constructor. Typically used by wxWidgets internals only.
     */
     wxDataViewEvent(wxEventType commandType = wxEVT_NULL,
                     int winid = 0);
-    wxDataViewEvent(const wxDataViewEvent& event);
-    //@}
 
     /**
         Returns the position of the column in the control or -1
@@ -2252,5 +2251,15 @@ public:
         Sets the value associated with this event.
     */
     void SetValue(const wxVariant& value);
+    
+    /**
+        Set wxDataObject for Drag'n'drop data transfer.
+    */
+    void SetDataObject( wxDataObject *obj );
+    
+    /**
+        Gets associated wxDataObject for Drag'n'drop data transfer.
+    */
+    wxDataObject *GetDataObject();
 };
 

samples/dataview/dataview.cpp

@@ -669,10 +669,7 @@ public:
     void OnGoto( wxCommandEvent &event);
     void OnAddMany( wxCommandEvent &event);
     
-    // DnD
+    void OnBeginDrag( wxDataViewEvent &event );
-    void OnDraggable( wxDataViewEvent &event );
-    void OnGetDragDataSize( wxDataViewEvent &event );
-    void OnGetDragData( wxDataViewEvent &event );
 
 private:
     wxDataViewCtrl* m_musicCtrl;
@@ -769,9 +766,7 @@ BEGIN_EVENT_TABLE(MyFrame, wxFrame)
 
     EVT_DATAVIEW_ITEM_CONTEXT_MENU(ID_MUSIC_CTRL, MyFrame::OnContextMenu)
     
-    EVT_DATAVIEW_ITEM_DRAGGABLE( ID_MUSIC_CTRL, MyFrame::OnDraggable )
+    EVT_DATAVIEW_ITEM_BEGIN_DRAG( ID_MUSIC_CTRL, MyFrame::OnBeginDrag )
-    EVT_DATAVIEW_ITEM_GET_DRAG_DATA_SIZE( ID_MUSIC_CTRL, MyFrame::OnGetDragDataSize )
-    EVT_DATAVIEW_ITEM_GET_DRAG_DATA( ID_MUSIC_CTRL, MyFrame::OnGetDragData )
 
     EVT_RIGHT_UP(MyFrame::OnRightClick)
 END_EVENT_TABLE()
@@ -1160,41 +1155,19 @@ void MyFrame::OnAbout(wxCommandEvent& WXUNUSED(event) )
     wxAboutBox(info);
 }
 
-void MyFrame::OnDraggable( wxDataViewEvent &event )
+void MyFrame::OnBeginDrag( wxDataViewEvent &event )
 {
+    wxDataViewItem item( event.GetItem() );
+        
     // only allow drags for item, not containers
-    event.SetDraggable( !m_music_model->IsContainer( event.GetItem() ) );
+    if (m_music_model->IsContainer( item ) )
-}
-
-void MyFrame::OnGetDragDataSize( wxDataViewEvent &event )
-{
-    if (event.GetDataFormat() == wxDF_TEXT)
     {
-        wxDataViewItem item( event.GetItem() );
+        event.Veto();
-        MyMusicModelNode *node = (MyMusicModelNode*) item.GetID();
-        
-        wxTextDataObject obj;
-        obj.SetText( node->m_artist );
-        size_t size = obj.GetDataSize( wxDF_TEXT );
-        event.SetDragDataSize( size );
         return;
     }
     
-    event.Skip();
-}
-
-void MyFrame::OnGetDragData( wxDataViewEvent &event )
-{
-    if (event.GetDataFormat() == wxDF_TEXT)
-    {
-        wxDataViewItem item( event.GetItem() );
     MyMusicModelNode *node = (MyMusicModelNode*) item.GetID();
-        
+    wxTextDataObject *obj = new wxTextDataObject;
-        wxTextDataObject obj;
+    obj->SetText( node->m_title );
-        obj.SetText( node->m_artist );
+    event.SetDataObject( obj );
-        obj.GetDataHere( wxDF_TEXT, event.GetDragDataBuffer() );
-        return;
-    }
-    
-    event.Skip();
 }

src/common/datavcmn.cpp

@@ -1235,9 +1235,7 @@ wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_COLUMN_HEADER_RIGHT_CLICK, wxDataViewEven
 wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_COLUMN_SORTED, wxDataViewEvent )
 wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_COLUMN_REORDERED, wxDataViewEvent )
 
-wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_ITEM_DRAGGABLE, wxDataViewEvent )
+wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_ITEM_BEGIN_DRAG, wxDataViewEvent )
-wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_ITEM_GET_DRAG_DATA_SIZE, wxDataViewEvent )
-wxDEFINE_EVENT( wxEVT_COMMAND_DATAVIEW_ITEM_GET_DRAG_DATA, wxDataViewEvent )
 
 // -------------------------------------
 // wxDataViewSpinRenderer

src/gtk/dataview.cpp

@@ -129,6 +129,8 @@ private:
     int                   m_sort_column;
     GtkTargetEntry        m_dragSourceTargetEntry;
     wxCharBuffer          m_dragSourceTargetEntryTarget;
+    wxDataObject         *m_dragDataObject;
+    wxDataObject         *m_dropDataObject;
 };
 
 
@@ -2878,6 +2880,9 @@ wxDataViewCtrlInternal::wxDataViewCtrlInternal( wxDataViewCtrl *owner,
     m_sort_column = -1;
     m_dataview_sort_column = NULL;
     
+    m_dragDataObject = NULL;
+    m_dropDataObject = NULL;
+
     if (!m_wx_model->IsVirtualListModel())
         InitTree();
 }
@@ -2885,6 +2890,9 @@ wxDataViewCtrlInternal::wxDataViewCtrlInternal( wxDataViewCtrl *owner,
 wxDataViewCtrlInternal::~wxDataViewCtrlInternal()
 {
     g_object_unref( m_gtk_model );
+    
+    delete m_dragDataObject;
+    delete m_dropDataObject;
 }
 
 void wxDataViewCtrlInternal::InitTree()
@@ -2936,16 +2944,28 @@ bool wxDataViewCtrlInternal::EnableDragSource( const wxDataFormat &format )
 gboolean wxDataViewCtrlInternal::row_draggable( GtkTreeDragSource *WXUNUSED(drag_source),
     GtkTreePath *path )
 {
+    delete m_dragDataObject;
+    
     GtkTreeIter iter;
     if (!get_iter( &iter, path )) return FALSE;
     wxDataViewItem item( (void*) iter.user_data );
 
-    wxDataViewEvent event( wxEVT_COMMAND_DATAVIEW_ITEM_DRAGGABLE, m_owner->GetId() );
+    wxDataViewEvent event( wxEVT_COMMAND_DATAVIEW_ITEM_BEGIN_DRAG, m_owner->GetId() );
     event.SetItem( item );
     event.SetModel( m_wx_model );
-    m_owner->HandleWindowEvent( event );
+    if (!m_owner->HandleWindowEvent( event ))
+        return FALSE;
         
-    return event.IsDraggable();
+    if (!event.IsAllowed())
+        return FALSE;
+        
+    wxDataObject *obj = event.GetDataObject();
+    if (!obj)
+        return FALSE;
+    
+    m_dragDataObject = obj;
+    
+    return TRUE;
 }
 
 gboolean
@@ -2962,27 +2982,25 @@ gboolean wxDataViewCtrlInternal::drag_data_get( GtkTreeDragSource *WXUNUSED(drag
     if (!get_iter( &iter, path )) return FALSE;
     wxDataViewItem item( (void*) iter.user_data );
 
-    wxDataViewEvent event( wxEVT_COMMAND_DATAVIEW_ITEM_GET_DRAG_DATA_SIZE, m_owner->GetId() );
+    if (!m_dragDataObject->IsSupported( selection_data->target ))
-    event.SetItem( item );
+        return FALSE;
-    event.SetModel( m_wx_model );
-    event.SetDataFormat( selection_data->target );
-    m_owner->HandleWindowEvent( event );
-    if (event.GetDragDataSize() < 1) return FALSE;
-    size_t size = (size_t) event.GetDragDataSize();
 
-    void *data = malloc( size );
+    size_t size = m_dragDataObject->GetDataSize( selection_data->target );
+    if (size == 0)
+        return FALSE;
+       
+    void *buf = malloc( size );
     
-    event.SetEventType( wxEVT_COMMAND_DATAVIEW_ITEM_GET_DRAG_DATA );
-    event.SetDragDataBuffer( data );
     gboolean res = FALSE;
-    if (m_owner->HandleWindowEvent( event ))
+    if (m_dragDataObject->GetDataHere( selection_data->target, buf ))
     {
-        gtk_selection_data_set( selection_data, selection_data->target,
-            8, (const guchar*) data, size );
         res = TRUE;
+    
+        gtk_selection_data_set( selection_data, selection_data->target,
+            8, (const guchar*) buf, size );
     }
 
-    free( data );
+    free( buf );
 
     return res;
 }