Hello Abhijith soman,

May be you can achieve this from below code:

In PY :-

from openerp import models, fields, api

class ClassName(models.Model):
    _name = 'class.name'

    @api.model
    def create(self, vals):
        result = super(ClassName, self).create(vals)
        self.is_create = True
        return result

    is_create = fields.Boolean('Is Create?')
    readonly_field = fields.Char('Readonly Field')

In XML :-

<record id="class_name_form_view" model="ir.ui.view">
    <field name="name">class.name.form.view</field>
    <field name="model">class.name</field>
    <field name="arch" type="xml">
        <form string="Name">
            <sheet>
                <field name="is_create" invisible="1"/>
                <field name="readonly_field" attrs="{'readonly' : [('is_create', '=', True)]}"/>
               </sheet>
        </form>
    </field>
</record>

Hope it will works for you.

Thanks,