Hi,

In order to show tax in Sales in Sales order line, we can following to configure so :-

• First go to Accounting menu and create a Tax by following Accounting >Taxes>Taxes

• Under the header Tax Computation , if we check the check box against “Tax included in price”, then this tax which are configuring/configured will be applied automatically on the Sale Price of the product and would be included within the price of the product which satisfies your query.

• After creation of the tax we need to go to the Sales>Products>Accounting>Customer Taxes. Here we must add the tax which we have just configured.

Hope this helps!!

Cheers.

For Odoo v8 look at this modules and make a review:

https://github.com/OCA/account-invoicing/pull/116

Thank you, 

but i want to add a custom field to order line

Hello Imam,

This Field is already available in sale.py named as "price_total" which include tax in Sub Total of Order Line.

You just need to add this filed in Sale Order form view

Please Add This Code in Your Xml File

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

<openerp>

<data>

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

<field name="name">sale.order.form</field>

<field name="model">sale.order</field>

<field name="inherit_id" ref="sale.view_order_form"/>

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

<xpath expr="//form/sheet/notebook/page[1]/field[@name='order_line']/tree/field[@name='tax_id']" position='after'>

<field name="price_total"/>

</xpath>

</field>

</record>

</data>

</openerp>

Thanks