Added an override for the admin add_view to prevent the change form template extends variable from not being populated.

README.md

@@ -218,8 +218,8 @@ ordering on top of that just seemed a little much in my opinion.
 django-admin-sortable is currently used in production.
 
 
-### What's new in 1.5?
-- More Brazilian Portugese translations (Thanks to @gladson)
+### What's new in 1.5.1?
+- Fixed a bug that could cause the change_form template to not be populated correctly when adding a new record.
 
 
 ### Future

adminsortable/__init__.py

@@ -1,4 +1,4 @@
-VERSION = (1, 5, 0)  # following PEP 386
+VERSION = (1, 5, 1)  # following PEP 386
 DEV_N = None
 
 

adminsortable/admin.py

@@ -168,6 +168,16 @@ class SortableAdmin(SortableAdminBase, ModelAdmin):
         }
         return render(request, self.sortable_change_list_template, context)
 
+    def add_view(self, request, form_url='', extra_context=None):
+        if extra_context is None:
+            extra_context = {}
+
+        extra_context.update({
+            'change_form_template_extends': self.change_form_template_extends
+        })
+        return super(SortableAdmin, self).add_view(request, form_url,
+            extra_context=extra_context)
+
     def change_view(self, request, object_id, extra_context=None):
         self.has_sortable_tabular_inlines = False
         self.has_sortable_stacked_inlines = False