it is sometimes very usefull to check if the value is not None before take the...

it is sometimes very usefull to check if the value is not None before take the decision to not create the cell


git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@3165 20353a03-c40f-0410-a6d1-a30d3c3de9de

product/ERP5Form/MatrixBox.py

@@ -406,7 +406,8 @@ class MatrixBoxValidator(Validator.Validator):
                                                       cell_position = (i,j, k))
                   value = my_field.validator.validate(my_field, key, REQUEST)
 
-                  if attribute_value != value and not my_field.get_value('hidden'):
+                  if (attribute_value != value or attribute_value not in('',None,(),[])) \
+                     and not my_field.get_value('hidden'):
                     # Only validate modified values from visible fields
                     if not result.has_key(kw):
                        result[kw] = {}