hi , I am trying to call refresh() def from onchange to refresh the page but it is not working.please suggest me the alternative which can help me in this situation  

@api.multi
def refresh(self):
    return {
        'type': 'ir.actions.client',
        'tag': 'reload',
        }


@api.onchange('barcode','workorder_sequence')
def onchange_barcode(self):
    if self.barcode:
       workorder_id = self.env['mrp.workorder'].search([('workorder_sequence', '=', self.workorder_sequence)])
        workorder_config_obj = self.env['workorder.configuration']
        config_id = workorder_config_obj.search([('barcode','=',self.barcode)])
        if not config_id:
            self.barcode = ''
            raise UserError(_(
                "Invalid Barcode Detected!!!"))
        else:
            if config_id.name =='start':             
                workorder_id.button_start()
                self.refresh()
            if config_id.name =='done':               
                workorder_id.record_production()
                self.refresh()
            if config_id.name =='pause':            
                workorder_id.button_pending()
                self.refresh()