Hello, I my problem is that the payroll journal bookings have only the reference but not the employee_id there in the column.

How can I add the employee_id to see from who is this booking. It's strange, because the reference it comes from the payroll Account.  

 This is my example, but it's not working:

from openerp.osv import fields, osv
 class account_move_line(osv.osv): 
    _inherits = 'account.move.line'
    _columns = { 
        'employee_id': fields.related('payslip','employee_id',type="char",relation="hr.payslip",string="employee_id",store=True,readonly=True),

    }

<?xml version="1.0" encoding="utf-8"?>

<openerp>

  <data>

        <record id="view_move_line_form" model="ir.ui.view">

        <field name="name">account.move.line.form</field>

        <field name="model">account.move.line</field>

        <field name="inherit_id" ref="account.view_move_line_tree" />

        <field name="arch" type="xml">

            <xpath expr="//field[@name='ref']" position="after">

                <field name="employee_id"/>

            </xpath>

        </field>

    </record>

  </data>

</openerp>

How to reference a field from a other object? I don't get it...