'form_view_ref' is not working in odoo 8.I want to open other view on many2one field.For example,

1.I created new form view of account_invoice object,Its not inheriting base view of account_invoice.its toatally different view,

2.this  is code line of it

<field name="invoice_id" context="{ 'form_view_ref': 'custom_module.view_new_invoice_form'}">

but still its opening basic account_invoice_form not my new invoice form view_new_invoice_form which is not inheriting basic account invoice form.

New view also using modal 'account.invoice'

please help me