account_invoice_line_pricelist/views/account_invoice.xml

<?xml version="1.0" encoding="UTF-8"?>
<openerp>
    <data>

        <record id="invoice_pricelist_form" model="ir.ui.view">
            <field name="name">account.invoice.pricelist.form</field>
            <field name="model">account.invoice</field>
            <field name="inherit_id" ref="account.invoice_form"/>
            <field name="arch" type="xml">
                <xpath expr="//field[@name='fiscal_position']" position="after">
                    <field name="pricelist_id" domain="[('type','=','sale'),('active','=',True)]" groups="product.group_sale_pricelist" attrs="{'readonly':[('state','!=','draft')]}" string="Lista de precios"/>
                </xpath>
                <xpath expr="//field[@name='invoice_line']/tree/field[@name='product_id']" position="attributes">
                    <attribute name="context">{'type': type, 'pricelist_id': parent.pricelist_id}</attribute>
                </xpath>
                <xpath expr="//field[@name='invoice_line']/tree/field[@name='quantity']" position="attributes">
                    <attribute name="context">{'type': type, 'pricelist_id': parent.pricelist_id}</attribute>
                    <attribute name="on_change">product_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.currency_id, parent.company_id, context)</attribute>
                </xpath>
            </field>
        </record>

        <record id="invoice_pricelist_supplier_form" model="ir.ui.view">
            <field name="name">account.invoice.pricelist.form</field>
            <field name="model">account.invoice</field>
            <field name="inherit_id" ref="account.invoice_supplier_form"/>
            <field name="arch" type="xml">
                <xpath expr="//field[@name='fiscal_position']" position="after">
                    <field name="pricelist_id" domain="[('type','=','purchase'),('active','=',True)]" groups="product.group_purchase_pricelist"  attrs="{'readonly':[('state','!=','draft')]}" string="Lista de precios"/>
                </xpath>
                <xpath expr="//field[@name='invoice_line']/tree/field[@name='product_id']" position="attributes">
                    <attribute name="context">{'type': type, 'pricelist_id': parent.pricelist_id}</attribute>
                </xpath>
                <xpath expr="//field[@name='invoice_line']/tree/field[@name='quantity']" position="attributes">
                    <attribute name="context">{'type': type, 'pricelist_id': parent.pricelist_id}</attribute>
                    <attribute name="on_change">product_id_change(product_id, uos_id, quantity, name, parent.type, parent.partner_id, parent.fiscal_position, price_unit, parent.currency_id, parent.company_id, context)</attribute>
                </xpath>
            </field>
        </record>

    </data>
</openerp>