uni_app 修改data里数据 页面不会重新渲染 没有实时响应 修改上一页的数据也是一样

// 删除空间商品（删除数组   页面数据不会变化）  
            delproduct(e) {  
                let that = this;  
                let index = e.currentTarget.dataset.index;  
                let productlist = that.productlist[that.roomid];  
                productlist.splice(index, 1);  
                let up = 'productlist[' + that.roomid + ']';  
                [up] = productlist;  
            },  

var cartList = this.list;  
                    var pages = getCurrentPages();  
                    var prevPage = pages[pages.length - 3];  
                    console.log(prevPage.productlist)  
                    var roomid = prevPage.roomid;  
                    var previndex = prevPage.num;  
                    console.log("roomid", roomid)  
                    var productlist = prevPage.productlist;  
                    // 新添加物品  
                    console.log(productlist[roomid])  
                    if (productlist[roomid] != undefined) {  
                        for (let i = 0; i < cartList.length; i++) {  
                            productlist[roomid].push(cartList[i])  
                        }  
                    } else {  
                        console.log("第一次")  
                        productlist[roomid] = cartList;  
                        console.log(cartList)  
                    }  
                    let pricenum = 0;  
                    let num = 0;  
                    for (let i in productlist[roomid]) {  
                        pricenum = Number(pricenum) + Number(productlist[roomid][i].original_price * productlist[roomid][i].number)  
                        num = Number(num) + Number(productlist[roomid][i].number)  
                    }  
                    prevPage.productlist = productlist;  
                    prevPage.pricenum = Math.floor(pricenum * 100) / 100;  
                    prevPage.numa = num;  
                    uni.setStorageSync("addlist", [])  
                    console.log(productlist)  
                    prevPage.num = -1;  
                    // return;  
                    uni.navigateBack({  
                        delta: 1 // 返回上一级页面。  
                    })