i have tried with delete="0" and options="{'no_delete':1}", not working
i dont want the field become readonly..
i use odoo 8
ex.
<field name="pettycash_ids" domain="[('branch_id','=',branch_id),('journal_id','=',journal_id),('division','=',division),('state','=','posted'),('amount_real','>',0)]" options="{'no_delete':1}" >