odoo/addons/sale_margin/sale_margin_view.xml

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

	<record model="ir.ui.view" id="sale_margin_sale_order">
		<field name="name">sale.order.margin.view.form</field>
		<field name="type">form</field>
		<field name="model">sale.order</field>
		<field name="inherit_id" ref="sale.view_order_form" />
		<field name="arch" type="xml">
			<field name="amount_total" position="after">
				<field name="margin"/>
			</field>
		</field>
	</record>
	
	<record model="ir.ui.view" id="sale_margin_sale_order_line">
		<field name="name">sale.order.line.margin.view.form</field>
		<field name="type">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/notebook/page/field[@name='order_line']/form/notebook/page/field[@name='price_unit']" position="after">
				<field name="purchase_price"/>
			</xpath>
		</field>
	</record>
	
	<record model="ir.ui.view" id="sale_margin_sale_order_line_form">
		<field name="name">sale.order.line.tree.margin.view.form</field>
		<field name="type">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/notebook/page/field[@name='order_line']/tree/field[@name='price_unit']" position="after">
				<field name="purchase_price"/>
			</xpath>
		</field>
	</record>
	
	<record model="ir.ui.view" id="sale_margin_sale_order_tree">
		<field name="name">sale.order.margin.view.tree</field>
		<field name="type">tree</field>
		<field name="model">sale.order</field>
		<field name="inherit_id" ref="sale.view_order_tree" />
		<field name="arch" type="xml">
			<field name="state" position="after">
				<field name="margin"/>
			</field>
		</field>
	</record>
   
	<record model="ir.ui.view" id="sale_margin_sale_order_line_tree">
		<field name="name">sale.order.margin.line.view.tree</field>
		<field name="type">tree</field>
		<field name="model">sale.order.line</field>
		<field name="inherit_id" ref="sale.view_order_line_tree" />
		<field name="arch" type="xml">
			<field name="price_subtotal" position="after">
				<field name="margin"/>
			</field>
		</field>
	</record>	
	
    
	<record model="ir.ui.view" id="view_picking_margin_out_form">
		<field name="name">picking.margin.view.form</field>
		<field name="type">form</field>
		<field name="model">stock.picking</field>
		<field name="inherit_id" ref="stock.view_picking_out_form" />
		<field name="arch" type="xml">
		<xpath expr="/form/notebook/page[@string='Additional info']" position="after">
			<page string="Customer Invoices">
                    <field colspan="4" name="invoice_ids" nolabel="1"/>
					<group col="10" colspan="4">
						<label colspan="6"/>
						<button name="create_invoice" icon='gtk-execute' string="Create Invoice" type="object"/>	
					</group>
            </page>	
		</xpath>
		</field>
	</record>
	
</data>
</openerp>