Use methode(self, obj) in InlineModelAdmin for use in readonly_fields. see https://docs.djangoproject.com/en/1.6/ref/contrib/admin/#django.contrib.admin.ModelAdmin.readonly_fields

"""
A read-only field can not only display data from a model’s field, it can also display the output of a model’s method or a method of the ModelAdmin class itself.
"""

Author: cc-db-p8

xadmin/plugins/inline.py

@@ -226,6 +226,9 @@ def instance_form(self, **kwargs):
                         elif inspect.ismethod(getattr(inst, readonly_field, None)):
                             value = getattr(inst, readonly_field)()
                             label = getattr(getattr(inst, readonly_field), 'short_description', readonly_field)
+                        elif inspect.ismethod(getattr(self, readonly_field, None)):
+                            value = getattr(self, readonly_field)(inst)
+                            label = getattr(getattr(self, readonly_field), 'short_description', readonly_field)
                         if value:
                             form.readonly_fields.append({'label': label, 'contents': value})
         return instance