Colocar referencia de producto en líneas de compras

purchase_reference.py

@@ -7,9 +7,10 @@ class purchase_order_line(models.Model):
 
     #obtener referencia
     @api.one
-    @api.onchange('product_id')
+    #@api.onchange('product_id')
+    @api.depends('product_id')
     def _get_factory_reference(self):
         self.product_factory_ref = self.product_id.factory_reference
 
     #campo
-    product_factory_ref = fields.Char(string='Referencia de fábrica', compute='_get_factory_reference')
+    product_factory_ref = fields.Char(string='Referencia de fábrica', compute='_get_factory_reference')

purchase_reference_view.xml

@@ -9,7 +9,10 @@
                <xpath expr="//tree/field[@name='product_id']" position="after">
                     <field name="product_factory_ref"/>
                </xpath>
+               <xpath expr="//tree/field[@name='name']" position="replace">
+                    <field name="name" invisible="1"/>
+               </xpath>
            </field>
        </record>
    </data>
-</openerp>
+</openerp>