0

数据可以请求到,但是可能是速度慢导致一开始undefined,这个怎么解决呢

store

import Util from "../../util/common";
import * as types from "../types";
import Vue from "vue";

// 容器
const state = {
  productDatas: "", //detail父组件请求的当前页面商品数据
  colSelected: 0, //0是index,表示第一个
  sizeSelected: 0, //0是index,表示第一个
  count: 0, //购物车里的商品数量
  carList: "", //购物车的商品列表
  fetchLoading: false, //全局加载状态的Loading
  selectedList: "", //已选择的购物车商品列表
  unSelectedList: "" //未选择的购物车商品列表,提交订单后用它替换carList
};

//更改 store 中的状态的唯一方法:提交 mutation
/*
  购物车逻辑:
      unSelectedList:未打钩的购物车商品列表
      SelectedList:已勾选的购物车商品列表
      carList:购物车商品列表
      当支付成功之后,购物车列表需要减掉SelectedList,留下unSelectedList
      直接用unSelectedList替换当前carList即可
*/
const mutations = {
  //异步请求的数据
  [types.SET_DATAS](state, res) {
    state.productDatas = res;
  },

  //详情页商品颜色的选择
  [types.CHANGE_COL_SELECTED](state, res) {
    state.colSelected = res;
  },

  //详情页商品尺寸的选择

  [types.CHANGE_SIZE_SELECTED](state, res) {
    state.sizeSelected = res;
  },

  // 向购物车商品列表添加商品
  [types.ADD_PRODUCT](state) {
    state.carList = Util.getLocal("carList");
  },

  //获取当前购物车商品数量
  [types.CHANGE_COUNT](state) {
    state.count = Util.getLocal("count");
  },

  // 重置购物车
  [types.RESET_CARLIST](state) {
    state.carList = Util.getLocal("carList");
  },

  // 重置购物车数量
  [types.RESET_COUNT](state) {
    state.count = Util.getLocal("carList").length;
  },

  // loading开关
  [types.SET_LOADING](state, res) {
    state.fetchLoading = res;
  },
  // 购物车里打钩的商品
  ["SET_SELECTEDLIST"](state, res) {
    state.selectedList = Util.getLocal("selectedList");
  },

  //购物车里没打钩的商品

  ["SET_UNSELECTEDLIST"](state) {
    state.unSelectedList = Util.getLocal("unSelectedList");
  }
};

let vm = new Vue({});

// action提交mutations,不直接更改状态(通过store.dispatch触发)
const actions = {
  // 父组件发送异步请求
  setDatas({ commit }) {
    let params={
      goodsId :"0d2420561a1b4360ad5f6a73067f0510",
      userId:''
    }
    vm.$fetch.api_detail
      .product(params)
      .then(({ data }) => {
        console.log(data.data)
        commit('SET_DATAS', data.data);
      })
      .catch(() => {});
    //  vm.$api({
    //      method:'post',
    //      url:"/detail"
    //    }).then(response=>{
    //      commit('SET_DATAS',response.data);
    //    })
  },

  // 购物车数量增减,true是加,false是减
  setLocalCount({ commit }, bool = true) {
    let count = Util.getLocal("count") || 0;
    if (bool) {
      Util.setLocal(++count, "count");
    } else {
      Util.setLocal(--count, "count");
    }
    commit(types.CHANGE_COUNT);
  },

  //网购物车列表添加数据
  addCarList({ commit }, res) {
    Util.setLocal(res, "carList", true);
    commit(types.ADD_PRODUCT);
  },

  //重新设置购物车商品列表,把打钩并提交的商品去掉,即保留unSelectedList

  resetCarList({ commit, getters }) {
    const unSelectedList = Util.getLocal("unSelectedList");
    Util.setLocal(unSelectedList, "carList");
    commit(types.RESET_CARLIST);
  },
  // 重置购物车数量Count,即没打钩的商品的数量
  resetCount({ commit, getters }) {
    const count = Util.getLocal("unSelectedList").length;
    Util.setLocal(count, "count");
    commit(types.RESET_COUNT);
  },

  // 删除购物车列表的某一项 (用新的数组直接替换)
  cutCarList({ commit }, res) {
    Util.setLocal(res, "carList");
    commit(types.RESET_CARLIST);
  },

  // 分别保存打钩的商品和为打钩的商品
  setSelectedList({ commit, getters }) {
    Util.setLocal(getters.selectedList, "selectedList");
    commit("SET_SELECTEDLIST");
    Util.setLocal(getters.unSelectedList, "unSelectedList");
    commit("SET_UNSELECTEDLIST");
  }
};

// 如同计算属性,处理state的某个状态
const getters = {
  selectedList(state) {
    // choseBool为真的商品 即打钩的商品
    if (state.carList !== "") {
      let arr = state.carList.filter(ele => {
        return ele.choseBool == true;
      });
      return arr;
    }
  },

  unSelectedList(state) {
    if (state.carList !== "") {
      let arr = state.carList.filter(ele => {
        return ele.choseBool == false;
      });
      return arr;
    }
  }
};

export default {
  state,
  actions,
  getters,
  mutations
};

详情页vue

<template lang="html">
  <div class="detail">
<div class="header">

  <mt-navbar v-model="selected">
    <mt-tab-item id="1">商品</mt-tab-item>
    <mt-tab-item id="2">库存</mt-tab-item>
  </mt-navbar>
</div>
<!-- tab-container -->
<mt-tab-container v-model="selected">
  <mt-tab-container-item id="1">
   <v-swiper> </v-swiper>
    <v-chose></v-chose>
    <v-content></v-content>
    <v-baseline></v-baseline>
    <v-footer></v-footer>
  </mt-tab-container-item>
  <mt-tab-container-item id="2">
    <mt-cell v-for="n in 4" :title="'测试 ' + n" />
  </mt-tab-container-item>

</mt-tab-container>
   
  </div>
</template>

<script>
import Swiper from "@/components/detail/swiper.vue";
import Chose from "@/components/detail/chose.vue";
import Content from "@/components/detail/content.vue";
import Footer from "@/components/detail/footer.vue";
import Baseline from "@/common/_baseline.vue";
import detail from "@/http/mock.js"; //模拟数据
export default {
  components: {
    "v-swiper": Swiper,
    "v-chose": Chose,
    "v-content": Content,
    "v-footer": Footer,
    "v-baseline": Baseline
  },
  data() {
    return {
      selected: "1"
    };
  },
  beforeCreate() {
    this.$store.dispatch("setDatas");
  }
};
</script>

<style lang="less" scoped>
.detail {
  width: 100%;
  padding-bottom: 14vw;
}
.mint-navbar {
  width:100px;
  margin:0 auto;
}
.mint-navbar .mint-tab-item.is-selected {
    border-bottom: 3px solid #333333;
    color: #333333;
    margin-bottom: 0;
}
</style>

里面引用swiper

====================华丽丽的分割线=======================

一开始判断的this.$store.state.detail.productDatas.goodsDetails.imgsList是否为undefined

不能判断imgsList是否是undefined,因为上级的是goodsDetails也不存在

感谢大神的回答!修改了一下解决问题了

 swiper() { 
       const {productDatas } = this.$store.state.detail;
       return productDatas ? this.$store.state.detail.productDatas.goodsDetails.imgsList :[];
    
    }

1个回答

0

已采纳

store里的state初始值里没有那些属性所以报undefined,在computed里 判断下underfined时 return 空数组
comptued:{

swiper(){
    const { productsdata }= this.store.state;
    return productsdata ?你的代码 :【】;
}


大致这样 手机
你那个state.detail是哪里来的

撰写答案