From 6fdecb93de1c392e028d0dcf8fd95fe89f2106fc Mon Sep 17 00:00:00 2001
From: Sergo <usakhelo@users.noreply.github.com>
Date: Sat, 3 Dec 2016 23:16:42 -0500
Subject: [PATCH] fixes #0002633 - body disappear if dragged out of Part
 container

---
 src/Gui/Document.cpp | 18 ++++++++++++++++++
 src/Gui/Tree.cpp     | 10 ++++++++++
 2 files changed, 28 insertions(+)

diff --git a/src/Gui/Document.cpp b/src/Gui/Document.cpp
index a8bbe86b6a..82df71cb17 100644
--- a/src/Gui/Document.cpp
+++ b/src/Gui/Document.cpp
@@ -62,6 +62,7 @@
 #include "View3DInventorViewer.h"
 #include "BitmapFactory.h"
 #include "ViewProviderDocumentObject.h"
+#include "ViewProviderDocumentObjectGroup.h"
 #include "Selection.h"
 #include "WaitCursor.h"
 #include "Thumbnail.h"
@@ -1476,5 +1477,22 @@ void Document::handleChildren3D(ViewProvider* viewProvider)
                 }
             }
         }
+    } else if (viewProvider && viewProvider->isDerivedFrom(ViewProviderDocumentObjectGroup::getClassTypeId())) {
+
+        ViewProviderDocumentObject* vp = static_cast<ViewProviderDocumentObject *>(viewProvider);
+        auto* ext = vp->getObject()->getExtensionByType<App::GroupExtension>();
+        std::vector<App::DocumentObject*> children = ext->getObjects();
+
+        for (auto& child : children) {
+            ViewProvider* ChildViewProvider = getViewProvider(child);
+            if (ChildViewProvider) {
+                for (BaseView* view : d->baseViews) {
+                    View3DInventor *activeView = dynamic_cast<View3DInventor *>(view);
+                    if (activeView && !activeView->getViewer()->hasViewProvider(ChildViewProvider)) {
+                        activeView->getViewer()->addViewProvider(ChildViewProvider);
+                    }
+                }
+            }
+        }
     }
 }
diff --git a/src/Gui/Tree.cpp b/src/Gui/Tree.cpp
index c1e5a73731..6e36f08e84 100644
--- a/src/Gui/Tree.cpp
+++ b/src/Gui/Tree.cpp
@@ -53,6 +53,8 @@
 #include "MenuManager.h"
 #include "Application.h"
 #include "MainWindow.h"
+#include "View3DInventor.h"
+#include "View3DInventorViewer.h"
 
 using namespace Gui;
 
@@ -634,6 +636,14 @@ void TreeWidget::dropEvent(QDropEvent *event)
                 Gui::ViewProvider* vpp = static_cast<DocumentObjectItem *>(parent)->object();
                 vpp->dragObject(obj);
             }
+
+            std::list<MDIView*> baseViews = gui->getMDIViews();
+            for (MDIView* view : baseViews) {
+                View3DInventor *activeView = dynamic_cast<View3DInventor *>(view);
+                if (activeView && !activeView->getViewer()->hasViewProvider(vpc)) {
+                    activeView->getViewer()->addViewProvider(vpc);
+                }
+            }
         }
         gui->commitCommand();
     }