From 408ac944164b2140e57c4040bf76ec67e120d776 Mon Sep 17 00:00:00 2001
From: wandererfan <wandererfan@gmail.com>
Date: Thu, 25 Apr 2019 14:53:52 -0400
Subject: [PATCH] Fix handling of orphan objects during Page delete

---
 src/Mod/TechDraw/App/DrawPage.cpp     | 29 +++++++++++++++++++--------
 src/Mod/TechDraw/App/DrawView.cpp     |  1 +
 src/Mod/TechDraw/App/DrawViewPart.cpp |  6 +++---
 3 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/src/Mod/TechDraw/App/DrawPage.cpp b/src/Mod/TechDraw/App/DrawPage.cpp
index 731e0b8967..0d34b1e44a 100644
--- a/src/Mod/TechDraw/App/DrawPage.cpp
+++ b/src/Mod/TechDraw/App/DrawPage.cpp
@@ -372,16 +372,29 @@ void DrawPage::unsetupObject()
     // Remove the Page's views & template from document
     App::Document* doc = getDocument();
     std::string docName = doc->getName();
+    std::string pageName = getNameInDocument();
 
-    while (Views.getValues().size() > 0 ) {
+    try {
         const std::vector<App::DocumentObject*> currViews = Views.getValues();
-        App::DocumentObject* child = currViews.front();
-        std::string viewName = child->getNameInDocument();
-        Base::Interpreter().runStringArg("App.getDocument(\"%s\").removeObject(\"%s\")",
-                                          docName.c_str(), viewName.c_str());
-    }
-    std::vector<App::DocumentObject*> emptyViews;      //probably superfluous
-    Views.setValues(emptyViews);
+        for (auto& v: currViews) {
+            //NOTE: the order of objects in Page.Views does not reflect the object hierarchy
+            //      this means that a ProjGroup could be deleted before it's child ProjGroupItems.
+            //      this causes problems when removing objects from document
+            if (v->isAttachedToDocument()) {
+                std::string viewName = v->getNameInDocument();
+                Base::Interpreter().runStringArg("App.getDocument(\"%s\").removeObject(\"%s\")",
+                                                  docName.c_str(), viewName.c_str());
+            } else {
+                Base::Console().Log("DP::unsetupObject - v(%s) is not in document. skipping\n", pageName.c_str());
+            }
+        }
+        std::vector<App::DocumentObject*> emptyViews;      //probably superfluous
+        Views.setValues(emptyViews);
+        
+   }
+   catch (...) {
+       Base::Console().Warning("DP::unsetupObject - %s - error while deleting children\n", getNameInDocument());
+   }
 
     App::DocumentObject* tmp = Template.getValue();
     if (tmp != nullptr) {
diff --git a/src/Mod/TechDraw/App/DrawView.cpp b/src/Mod/TechDraw/App/DrawView.cpp
index 4cc7afc3d3..399fa21eaa 100644
--- a/src/Mod/TechDraw/App/DrawView.cpp
+++ b/src/Mod/TechDraw/App/DrawView.cpp
@@ -91,6 +91,7 @@ DrawView::~DrawView()
 
 App::DocumentObjectExecReturn *DrawView::execute(void)
 {
+//    Base::Console().Message("DV::execute() - %s\n",getNameInDocument());
     handleXYLock();
     requestPaint();
     return App::DocumentObject::execute();
diff --git a/src/Mod/TechDraw/App/DrawViewPart.cpp b/src/Mod/TechDraw/App/DrawViewPart.cpp
index c99f250907..c9c78ae0d6 100644
--- a/src/Mod/TechDraw/App/DrawViewPart.cpp
+++ b/src/Mod/TechDraw/App/DrawViewPart.cpp
@@ -160,7 +160,6 @@ DrawViewPart::~DrawViewPart()
 TopoDS_Shape DrawViewPart::getSourceShape(void) const
 {
 //     Base::Console().Message("DVP::getSourceShape() - %s\n", getNameInDocument());
-
     TopoDS_Shape result;
     const std::vector<App::DocumentObject*>& links = Source.getValues();
     if (links.empty())  {
@@ -276,7 +275,7 @@ TopoDS_Shape DrawViewPart::getSourceShapeFused(void) const
 
 App::DocumentObjectExecReturn *DrawViewPart::execute(void)
 {
-//    Base::Console().Message("DVP::execute() - %s\n", getNameInDocument());
+//    Base::Console().Message("DVP::execute() - %s\n",getNameInDocument());
     if (!keepUpdated()) {
         return App::DocumentObject::StdReturn;
     }
@@ -346,6 +345,7 @@ App::DocumentObjectExecReturn *DrawViewPart::execute(void)
 #endif //#if MOD_TECHDRAW_HANDLE_FACES
 
     requestPaint();
+//    Base::Console().Message("DVP::execute - %s - exits\n",getNameInDocument());
     return App::DocumentObject::StdReturn;
 }
 
@@ -442,11 +442,11 @@ TechDrawGeometry::GeometryObject* DrawViewPart::buildGeometryObject(TopoDS_Shape
         go->extractGeometry(TechDrawGeometry::ecUVISO,
                             false);
     }
-
     auto end   = chrono::high_resolution_clock::now();
     auto diff  = end - start;
     double diffOut = chrono::duration <double, milli> (diff).count();
     Base::Console().Log("TIMING - %s DVP spent: %.3f millisecs in GO::extractGeometry\n",getNameInDocument(),diffOut);
+
     const std::vector<TechDrawGeometry::BaseGeom  *> & edges = go->getEdgeGeometry();
     if (edges.empty()) {
         Base::Console().Log("DVP::buildGO - NO extracted edges!\n");