From 55d53bf4d550b545e21338b501facd35cef1e5d9 Mon Sep 17 00:00:00 2001
From: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>
Date: Mon, 9 May 2016 19:55:03 -0400
Subject: [PATCH] Equate queryset model instances with deffered fields to their
 parent model class when resolving UI model columns. This will allow models
 using .defer or .only optimizations to render properly on list views.

---
 mayan/apps/navigation/classes.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/mayan/apps/navigation/classes.py b/mayan/apps/navigation/classes.py
index 2151585b08..d63d9b4fb3 100644
--- a/mayan/apps/navigation/classes.py
+++ b/mayan/apps/navigation/classes.py
@@ -349,7 +349,10 @@ class SourceColumn(object):
                 try:
                     return cls._registry[source.__class__]
                 except KeyError:
-                    return ()
+                    try:
+                        return cls._registry[source._meta.parents.items()[0][0]]
+                    except IndexError:
+                        return ()
         except TypeError:
             # unhashable type: list
             return ()