Hello anyone reading.....got the answer!!!! I solved it this way! After creating the main form view of my model, i inherited the view and modified it for my manager. Hope it helps anyone looking----------
<record  id="inherited_stock_location_view_form_inherit_store_manager_write_access"  model="ir.ui.view">      
<field name="name">inherited.stock.location.inherit.store.form.custom  </field>            
<field name="model">stock.location</field>            
<field name="inherit_id"  ref="shoe_merchandising.inherited_stock_location_view_form_inherit_store" />           
 <field name="groups_id"     eval="[(6, 0, [ref('shoe_merchandising.merchandising_group_manager')])]" />           
 <field name="arch" type="xml">                
<xpath expr="//field[@name='store_manager_id']" position="attributes">                    
<attribute name="attrs">   {'readonly':[('state','in',['cancel'])]}   </attribute> 
 </xpath>  
</field> 
 </record>