SAP UI5，多页面导航oRouter显示undefined

onListPress: function(oEvent){
                var oRouter = UIComponent.getRouterFor(this);
                var oItem = oEvent.getSource();
                var sPath = oItem.getBindingContext().getPath();
                oRouter.navTo("detail", {
                    supplierPath: encodeURIComponent(sPath)
               });;
            }