Hi  Kiran,

You can achieve this by using following code

In Python

from lxml import etree

@api.model

def fields_view_get(self, view_id='you_form_view_id', view_type='form', toolbar=False, submenu=False):
    res = super(ClassName, self).fields_view_get(view_id=view_id, view_type=view_type, toolbar=toolbar,
                                                  submenu=submenu)
    doc = etree.XML(res['arch'])
    if self.env.user.has_group('group1'):
        for node in doc.xpath("//field[@name='field1']"):
            node.set('modifiers', '{"readonly": true}')
        for node in doc.xpath("//field[@name='field2']"):
            node.set('modifiers', '{"readonly": true}')
    elif self.env.user.has_group('group2'):
        for node in doc.xpath("//field[@name='field2']"):
            node.set('modifiers', '{"readonly": true}')
        for node in doc.xpath("//field[@name='field3']"):
            node.set('modifiers', '{"readonly": true}')
    res['arch'] = etree.tostring(doc)
    return res

You need to assign that user to specific Group based on that group you can achieve that easily

Othewise based on Login also, you can achieve

Thanks

Hi if you want to make the field readonly for a particular group, say for all the users present in a group.. you can use fields view get function to make the field readonly for a particular user.. or you can create your own record rules... 

There is another alternative, you can create a boolean field and make it invisible.. use compute function to make the field True/False based on the user logged in using self.id .... you can then use this boolean field in attrs for your field...

<field name="add_portal_id" attrs="{'readonly': [('your_boolean_field', '=', True)]}"/>

Here attrs will not work for the dynamic domain so (maybe only) option is passed context from the action and eval it on the field

like pass 'readonly_user' key from action context base on a particular user and

            <field name="add_portal_id"  string="Portal Name" readonly="context.get('readonly_user', False)"/>
​