Gui: fix DAG view icon sync problem

src/Gui/DAGView/DAGModel.cpp

@@ -246,26 +246,21 @@ void Model::slotNewObject(const ViewProviderDocumentObject &VPDObjectIn)
   auto *rectangle = (*theGraph)[virginVertex].rectangle.get();
   rectangle->setEditingBrush(QBrush(Qt::yellow));
   
-  (*theGraph)[virginVertex].icon->setPixmap(VPDObjectIn.getIcon().pixmap(iconSize, iconSize));
+  auto icon = (*theGraph)[virginVertex].icon;
+  icon->setPixmap(VPDObjectIn.getIcon().pixmap(iconSize, iconSize));
   (*theGraph)[virginVertex].stateIcon->setPixmap(passPixmap);
   (*theGraph)[virginVertex].text->setFont(this->font());
+  (*theGraph)[virginVertex].connChangeIcon = 
+      const_cast<Gui::ViewProviderDocumentObject&>(VPDObjectIn).signalChangeIcon.connect(
+          boost::bind(&Model::slotChangeIcon, this, boost::cref(VPDObjectIn), icon));
   
   graphDirty = true;
-  
-  //we are here before python objects are instantiated. so at this point
-  //the getIcon method doesn't reflect the python override.
-  //so we hack in a delay to get the latest icon and set it for the graphics item.
-  lastAddedVertex = virginVertex;
-  QTimer::singleShot(0, this, SLOT(iconUpdateSlot()));
+  lastAddedVertex = Graph::null_vertex();
 }
 
-void Model::iconUpdateSlot()
+void Model::slotChangeIcon(const ViewProviderDocumentObject &VPDObjectIn, std::shared_ptr<QGraphicsPixmapItem> icon)
 {
-  if (lastAddedVertex == Graph::null_vertex())
-    return;
-  const ViewProviderDocumentObject *VPDObject = findRecord(lastAddedVertex, *graphLink).VPDObject;
-  (*theGraph)[lastAddedVertex].icon->setPixmap(VPDObject->getIcon().pixmap(iconSize, iconSize));
-  lastAddedVertex = Graph::null_vertex();
+  icon->setPixmap(VPDObjectIn.getIcon().pixmap(iconSize, iconSize));
   this->invalidate();
 }
 
@@ -286,6 +281,8 @@ void Model::slotDeleteObject(const ViewProviderDocumentObject &VPDObjectIn)
   
   if (vertex == lastAddedVertex)
     lastAddedVertex = Graph::null_vertex();
+
+  (*theGraph)[vertex].connChangeIcon.disconnect();
   
   //remove the actual vertex.
   boost::clear_vertex(vertex, *theGraph);

src/Gui/DAGView/DAGModel.h

@@ -81,7 +81,6 @@ namespace Gui
       void renameRejectedSlot();
       void editingStartSlot();
       void editingFinishedSlot();
-      void iconUpdateSlot(); //!< needed because python objects are not ready.
       
     private:
       Model(){}
@@ -101,6 +100,7 @@ namespace Gui
       void slotChangeObject(const Gui::ViewProviderDocumentObject &VPDObjectIn, const App::Property& propertyIn);
       void slotInEdit(const Gui::ViewProviderDocumentObject &VPDObjectIn);
       void slotResetEdit(const Gui::ViewProviderDocumentObject &VPDObjectIn);
+      void slotChangeIcon(const Gui::ViewProviderDocumentObject &VPDObjectIn, std::shared_ptr<QGraphicsPixmapItem> icon);
       
       std::shared_ptr<GraphLinkContainer> graphLink;
       std::shared_ptr<Graph> theGraph;

src/Gui/DAGView/DAGModelGraph.h

@@ -35,6 +35,7 @@
 #include <boost/multi_index_container.hpp>
 #include <boost/multi_index/member.hpp>
 #include <boost/multi_index/ordered_index.hpp>
+#include <boost/signals2.hpp>
 
 #include "DAGRectItem.h"
 
@@ -79,6 +80,7 @@ namespace Gui
       std::shared_ptr<QGraphicsPixmapItem> stateIcon; //!< visible Icon
       std::shared_ptr<QGraphicsPixmapItem> icon; //!< icon
       std::shared_ptr<QGraphicsTextItem> text; //!< text
+      boost::signals2::connection connChangeIcon;
       int row; //!< row for this entry.
       ColumnMask column; //!< column number containing the point.
       int topoSortIndex;