From c1d799e8315bd9dcafd52d4b9c4413a0b2142b17 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Stefan=20Tr=C3=B6ger?= <stefantroeger@gmx.net>
Date: Mon, 21 Oct 2013 21:49:54 +0200
Subject: [PATCH] prevent dangling pointers by clearing the active assembly
 after it was deleted

---
 src/Mod/Assembly/Gui/AppAssemblyGuiPy.cpp     | 61 ++++++++++++-------
 src/Mod/Assembly/Gui/ViewProviderAssembly.cpp |  4 ++
 2 files changed, 42 insertions(+), 23 deletions(-)

diff --git a/src/Mod/Assembly/Gui/AppAssemblyGuiPy.cpp b/src/Mod/Assembly/Gui/AppAssemblyGuiPy.cpp
index 9f75430d3..84fbd5d71 100644
--- a/src/Mod/Assembly/Gui/AppAssemblyGuiPy.cpp
+++ b/src/Mod/Assembly/Gui/AppAssemblyGuiPy.cpp
@@ -37,53 +37,63 @@
 #include <Mod/Assembly/App/ItemPy.h>
 
 // pointer to the active assembly object
-Assembly::Item                  *ActiveAsmObject =0;
-Gui::Document                   *ActiveGuiDoc    =0;
-App::Document                   *ActiveAppDoc    =0;
-Gui::ViewProviderDocumentObject *ActiveVp        =0;
+Assembly::Item*                  ActiveAsmObject =0;
+Gui::Document*                   ActiveGuiDoc    =0;
+App::Document*                   ActiveAppDoc    =0;
+Gui::ViewProviderDocumentObject* ActiveVp        =0;
 
 
 
 /* module functions */
-static PyObject * setActiveAssembly(PyObject *self, PyObject *args)
-{   
-    if(ActiveAsmObject){
+static PyObject* setActiveAssembly(PyObject* self, PyObject* args)
+{
+    if(ActiveAsmObject) {
         // check if the document not already closed
         std::vector<App::Document*> docs = App::GetApplication().getDocuments();
-        for(std::vector<App::Document*>::const_iterator it=docs.begin();it!=docs.end();++it)
-            if(*it == ActiveAppDoc){
+        for(std::vector<App::Document*>::const_iterator it=docs.begin(); it!=docs.end(); ++it)
+            if(*it == ActiveAppDoc) {
                 ActiveGuiDoc->signalHighlightObject(*ActiveVp,Gui::Blue,false);
                 break;
             }
-                
+
         ActiveAsmObject = 0;
         ActiveGuiDoc    =0;
         ActiveAppDoc    =0;
         ActiveVp        =0;
     }
 
-    PyObject *object=0;
-    if (PyArg_ParseTuple(args,"|O!",&(Assembly::ItemPy::Type), &object)&& object) {
+    PyObject* object=0;
+    if(PyArg_ParseTuple(args,"|O!",&(Assembly::ItemPy::Type), &object)&& object) {
         Assembly::Item* Item = static_cast<Assembly::ItemPy*>(object)->getItemPtr();
         // Should be set!
-        assert(Item);    
+        assert(Item);
 
-        // get the gui document of the Assembly Item 
+        // get the gui document of the Assembly Item
         ActiveAsmObject = Item;
         ActiveAppDoc = Item->getDocument();
         ActiveGuiDoc = Gui::Application::Instance->getDocument(ActiveAppDoc);
-        ActiveVp = dynamic_cast<Gui::ViewProviderDocumentObject*> (ActiveGuiDoc->getViewProvider(Item)) ;
+        ActiveVp = dynamic_cast<Gui::ViewProviderDocumentObject*>(ActiveGuiDoc->getViewProvider(Item)) ;
         ActiveGuiDoc->signalHighlightObject(*ActiveVp,Gui::Blue,true);
     }
 
     Py_Return;
 }
 
+static PyObject* clearActiveAssembly(PyObject* self,  PyObject* args) {
+
+    ActiveAsmObject = 0;
+    ActiveGuiDoc    =0;
+    ActiveAppDoc    =0;
+    ActiveVp        =0;
+    
+    Py_Return;
+}
+
 /* module functions */
-static PyObject * getActiveAssembly(PyObject *self, PyObject *args)
-{   
-    if(ActiveAsmObject){
- 
+static PyObject* getActiveAssembly(PyObject* self, PyObject* args)
+{
+    if(ActiveAsmObject) {
+
         return ActiveAsmObject->getPyObject();
     }
 
@@ -94,10 +104,15 @@ static PyObject * getActiveAssembly(PyObject *self, PyObject *args)
 
 /* registration table  */
 struct PyMethodDef AssemblyGui_Import_methods[] = {
-    {"setActiveAssembly"       ,setActiveAssembly      ,METH_VARARGS,
-     "setActiveAssembly(AssemblyObject) -- Set the Assembly object in work."},
-    {"getActiveAssembly"       ,getActiveAssembly      ,METH_VARARGS,
-     "getActiveAssembly() -- Returns the Assembly object in work."},
+    {   "setActiveAssembly"       ,setActiveAssembly      ,METH_VARARGS,
+        "setActiveAssembly(AssemblyObject) -- Set the Assembly object in work."
+    },
+    {   "getActiveAssembly"       ,getActiveAssembly      ,METH_VARARGS,
+        "getActiveAssembly() -- Returns the Assembly object in work."
+    },
+    {   "clearActiveAssembly"       ,clearActiveAssembly      ,METH_VARARGS,
+        "clearActiveAssembly() -- Removes the current active Assembly as object in work"
+    },
 
     {NULL, NULL}                   /* end of table marker */
 };
diff --git a/src/Mod/Assembly/Gui/ViewProviderAssembly.cpp b/src/Mod/Assembly/Gui/ViewProviderAssembly.cpp
index 8cdb3fe57..301e569d6 100644
--- a/src/Mod/Assembly/Gui/ViewProviderAssembly.cpp
+++ b/src/Mod/Assembly/Gui/ViewProviderAssembly.cpp
@@ -35,6 +35,8 @@
 
 using namespace AssemblyGui;
 
+extern Assembly::ItemAssembly* ActiveAsmObject;
+
 PROPERTY_SOURCE(AssemblyGui::ViewProviderItemAssembly,AssemblyGui::ViewProviderItem)
 
 ViewProviderItemAssembly::ViewProviderItemAssembly()
@@ -43,6 +45,8 @@ ViewProviderItemAssembly::ViewProviderItemAssembly()
 
 ViewProviderItemAssembly::~ViewProviderItemAssembly()
 {
+    if(getObject() == ActiveAsmObject)
+        Gui::Command::doCommand(Gui::Command::Doc,"AssemblyGui.clearActiveAssembly()");
 }
 
 bool ViewProviderItemAssembly::doubleClicked(void)