sis_stock_transfer/views/picking_product_view.xml

<?xml version="1.0"?>
<openerp>
    <data>
        <!-- <record id="view_sis_transfer_form" model="ir.ui.view">
            <field name="name">view_sis_transfer_form</field>
            <field name="model">sis.stock.transfer</field>
            <field name="inherit_id" ref="stock_warehouse_transfer.stock_warehouse_transfer_view_form"/>
            <field name="arch" type="xml">
                <field name="lines" position="before">
                    <button name="%(action_purchase_add_multiple)d"
                            type="action" string="Activar Lector"
                            attrs="{'invisible':[('state','not in',['draft','sent'])]}"/>
                </field>
            </field>
        </record> -->
    </data>
</openerp>