this.screen_selector = new module.ScreenSelector({
                pos: this.pos,
                screen_set:{
                    'products': this.product_screen,
                    'payment' : this.payment_screen,
                    'scale':    this.scale_screen,
                    'receipt' : this.receipt_screen,
                    'clientlist': this.clientlist_screen,
                },
                popup_set:{
                    'error': this.error_popup,
                    'error-barcode': this.error_barcode_popup,
                    'error-traceback': this.error_traceback_popup,
                    'confirm': this.confirm_popup,
                    'unsent-orders': this.unsent_orders_popup,
                },
                default_screen: 'products',
                default_mode: 'cashier',
            });