Minor fix for previous commit

src/ifcblenderexport/blenderbim/bim/module/model/grid.py

@@ -31,7 +31,11 @@ def add_object(self, context):
         bpy.ops.bim.assign_class(obj=obj.name, ifc_class="IfcGrid")
         grid = self.file.by_id(obj.BIMObjectProperties.ifc_definition_id)
         if has_site_collection:
-            bpy.ops.bim.assign_container(relating_structure=grandchild.name, related_element=obj.name)
+            site_obj = bpy.data.objects.get(grandchild.name)
+            if site_obj and site_obj.BIMObjectProperties.ifc_definition_id:
+                bpy.ops.bim.assign_container(
+                    relating_structure=site_obj.BIMObjectProperties.ifc_definition_id, related_element=obj.name
+                )
 
     axes_collection = bpy.data.collections.new("UAxes")
     collection.children.link(axes_collection)

src/ifcblenderexport/blenderbim/bim/module/model/pie.py

@@ -98,13 +98,13 @@ class PieUpdateContainer(bpy.types.Operator):
         for obj in context.selected_objects:
             if not obj.BIMObjectProperties.ifc_definition_id:
                 continue
-            relating_structure = None
             for collection in obj.users_collection:
-                relating_structure_obj = bpy.data.objects.get(collection.name)
-                if not relating_structure_obj or not relating_structure_obj.BIMObjectProperties.ifc_definition_id:
-                    continue
-                relating_structure = relating_structure_obj
-            bpy.ops.bim.assign_container(relating_structure=relating_structure.name, related_element=obj.name)
+                spatial_obj = bpy.data.objects.get(collection.name)
+                if spatial_obj and spatial_obj.BIMObjectProperties.ifc_definition_id:
+                    bpy.ops.bim.assign_container(
+                        relating_structure=spatial_obj.BIMObjectProperties.ifc_definition_id, related_element=obj.name
+                    )
+                    break
         return {"FINISHED"}
 
 

src/ifcblenderexport/blenderbim/bim/module/root/operator.py

@@ -160,8 +160,12 @@ class AssignClass(bpy.types.Operator):
         for collection in obj.users_collection:
             if "Ifc" not in collection.name or collection.name == obj.name:
                 continue
-            bpy.ops.bim.assign_container(relating_structure=collection.name, related_element=obj.name)
-            break
+            spatial_obj = bpy.data.objects.get(collection.name)
+            if spatial_obj and spatial_obj.BIMObjectProperties.ifc_definition_id:
+                bpy.ops.bim.assign_container(
+                    relating_structure=spatial_obj.BIMObjectProperties.ifc_definition_id, related_element=obj.name
+                )
+                break
 
 
 class UnassignClass(bpy.types.Operator):