ERP5/InteractionWorkflow.py: improve showAsXML according to workflow showASXML.

product/ERP5/InteractionWorkflow.py

@@ -454,17 +454,18 @@ class InteractionWorkflowDefinition (DCWorkflowDefinition, ActiveObject):
             property_value = expression.text
           else:
             property_value = ''
-          sub_object = SubElement(variable, property_id, attrib=dict(type='string'))
         else:
-          property_value = vdef.__dict__[property_id]
-          property_type = variable_prop_id_to_show[property_id]
-          sub_object = SubElement(variable, property_id, attrib=dict(type=property_type))
+          property_value = getattr(vdef, property_id, '')
+        if property_value is None or property_value == [] or property_value ==():
+          property_value = ''
+        property_type = variable_prop_id_to_show[property_id]
+        sub_object = SubElement(variable, property_id, attrib=dict(type=property_type))
         sub_object.text = str(property_value)
 
     # 3. Script as XML
     script_reference_list = []
     script_id_list = sorted(self.scripts.keys())
-    script_prop_id_to_show = {'title':'string', 'body':'string', 'parameter_signature':'string'}
+    script_prop_id_to_show = {'body':'string', 'parameter_signature':'string'}
     for sid in script_id_list:
       script_reference_list.append(sid)
     scripts = SubElement(interaction_workflow, 'scripts', attrib=dict(script_list=str(script_reference_list),