Check if DnD is started from a mouse event.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@43429 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/gtk/dnd.cpp

@@ -39,13 +39,16 @@ extern bool g_blockEventsOnDrag;
 // the flags used for the last DoDragDrop()
 static long gs_flagsForDrag = 0;
 
+#ifdef __WXDEBUG__
 // the trace mask we use with wxLogTrace() - call
 // wxLog::AddTraceMask(TRACE_DND) to enable the trace messages from here
 // (there are quite a few of them, so don't enable this by default)
 static const wxChar *TRACE_DND = _T("dnd");
+#endif
 
+// global variables because GTK+ DnD want to have the
+// mouse event that caused it
 extern GdkEvent *g_lastMouseEvent;
-
 extern int       g_lastButtonNumber;
 
 //----------------------------------------------------------------------------
@@ -835,6 +838,14 @@ wxDragResult wxDropSource::DoDragDrop(int flags)
     if (g_blockEventsOnDrag)
         return wxDragNone;
 
+    // don't start dragging if no button is down
+    if (g_lastButtonNumber == 0)
+        return wxDragNone;
+        
+    // we can only start a drag after a mouse event
+    if (g_lastMouseEvent == NULL)
+        return wxDragNone;
+
     // disabled for now
     g_blockEventsOnDrag = true;
 
@@ -855,9 +866,6 @@ wxDragResult wxDropSource::DoDragDrop(int flags)
     }
     delete[] array;
 
-    /* don't start dragging if no button is down */
-    if (g_lastButtonNumber)
-    {
     int action = GDK_ACTION_COPY;
     if ( flags & wxDrag_AllowMove )
         action |= GDK_ACTION_MOVE;
@@ -883,7 +891,6 @@ wxDragResult wxDropSource::DoDragDrop(int flags)
     m_retValue = ConvertFromGTK(context->action);
     if ( m_retValue == wxDragNone )
          m_retValue = wxDragCancel;
-    }
 
     g_blockEventsOnDrag = false;
 

src/gtk/window.cpp

@@ -210,7 +210,8 @@ wxWindowGTK *g_focusWindowLast = (wxWindowGTK*) NULL;
 // yet, defer setting the focus to idle time.
 wxWindowGTK *g_delayedFocus = (wxWindowGTK*) NULL;
 
-// Save the last mouse event for drag start
+// global variables because GTK+ DnD want to have the
+// mouse event that caused it
 GdkEvent    *g_lastMouseEvent = (GdkEvent*) NULL;
 int          g_lastButtonNumber = 0;
 
@@ -1607,8 +1608,10 @@ gtk_window_button_press_callback( GtkWidget *widget,
 
     if (win->GTKProcessEvent( event ))
     {
+        g_lastMouseEvent = NULL;
         return TRUE;
     }
+    g_lastMouseEvent = NULL;
 
     if (event_type == wxEVT_RIGHT_DOWN)
     {
@@ -1749,7 +1752,11 @@ gtk_window_motion_notify_callback( GtkWidget *widget,
         }
     }
 
-    return win->GTKProcessEvent(event);
+    bool ret = win->GTKProcessEvent(event);
+    
+    g_lastMouseEvent = NULL;
+
+    return ret;
 }
 
 //-----------------------------------------------------------------------------