I write a "def confirm_sale(self, cr, uid, ids, context=None):…………" in saly.py/class sale.order, and i write the "ir.actions.server" like:

<record id="action_sale_order_action_cancel" model="ir.actions.server">
<field name="name">Cancel1</field>
<field name="type">ir.actions.server</field>
<field name="model_id" ref="model_sale_order"/>
<field name="state">code</field>
**<field name="code">obj.confirm_sale(context=context)</field>**
</record>
<record id="id_action_sale_order_action_cancel" model="ir.values">
<field name="name">Cancel</field>
<field name="action_id" ref="action_sale_order_action_cancel"/>
<field name="value" eval="'ir.actions.server,' + str(ref('action_sale_order_action_cancel'))"/>
<field name="key">action</field>
<field name="model_id" ref="model_sale_order"/>
<field name="model">sale.order</field>
<field name="key2">client_action_multi</field>
</record>

but it always take the error:
" openerp.tools.safe_eval: Cannot eval u'obj.confirm_sale(context=context)' "

" AttributeError: "Field 'confirm_sale' does not exist in object 'browse_record(sale.order, 10)'" "

But if I replace confirm_sale with action_button_confirm , which has already exist in saly.py, it can work ..

I think I should add something more..But I don't know how to collect...