Suppose we want to add two different views for a custom model name 'purchase.req'. One is for the base user and another is for the manager.

<record model="ir.actions.act_window" id="purchase_order_action">
         <field name="name">Purchase Requisition</field>
         <field name="res_model">purchase.req</field>
         <field name="view_mode">tree,form</field>
         <field name="context">{}</field>
                 <field
                   name="view_ids"
                   eval="[
                       (5, 0, 0),
                       (0, 0, {'sequence': 1, 'view_mode': 'tree', 'view_id': ref('purchase_req_tree')}),
                       (0, 0, {'sequence': 2, 'view_mode': 'form', 'view_id': ref('purchase_req_form')}),    
                    ]"/>

         <field name="help" type="html">
             <p class="o_view_nocontent_smiling_face">Create the First Purchase Requisition !
             </p>
         </field>
     </record>

Here reference tree and form view will be called for this action.