705_vuex组件数据共享

Person组件：

<template>
  <div>
    <h1>人员列表</h1>
    <h3>Count组件求和为:{{ sum }}</h3>
    <input type="text" placeholder="请输入名字" v-model="name" />
    <button @click="add">添加</button>
    <ul>
      <li v-for="p in personList" :key="p.id">{{ p.name }}</li>
      <li></li>
      <li></li>
      <li></li>
    </ul>
  </div>
</template>

<script>
import { mapState } from "vuex";
import { nanoid } from "nanoid";
export default {
  name: "Person",
  data() {
    return {
      name: "",
    };
  },
  computed: {
    ...mapState(["personList", "sum"]),
  },
  methods: {
    add() {
      const personObj = { id: nanoid(), name: this.name };
      this.$store.commit("ADD_PERSON", personObj);
      this.name = "";
    },
  },
};
</script>

<style>
</style>

Count组件

<template>
  <div>
    <h1>当前求和为:{{ sum }}</h1>
    <h4>当前求和乘以10倍为:{{ bigSum }}</h4>
    <h4>我在{{ school }},学{{ subject }}</h4>
    <h3>Person组件的总人数是：{{ personList.length }}</h3>
    <select v-model="n">
      <!-- value默认是字符串类型，加上":"后 所有冒号里面的内容变成js表达式来解析-->
      <!-- 或者使用 v-model.number="n" 强制类型转换-->
      <option :value="1">1</option>
      <option :value="2">2</option>
      <option :value="3">3</option>
    </select>
    <!-- 要事先传递参数 -->
    <button @click="increment(n)">+</button>
    <button @click="decrement(n)">-</button>
    <button @click="incrementOdd(n)">当前求和为奇数再加</button>
    <button @click="incrementWait(n)">等一等再加</button>
  </div>
</template>

<script>
import { mapState, mapGetters, mapMutations, mapActions } from "vuex";

export default {
  name: "Count",
  data() {
    return {
      n: 1, //用户选择的数字
    };
  },

  methods: {
    //借助mapMutations生成对应的方法，方法会调用commit去联系Mutations
    ...mapMutations({ increment: "JIA", decrement: "JIAN" }),

    //借助mapActations生成对应的方法，方法会调用dispatch去联系actions
    ...mapActions({ incrementOdd: "jiaOdd", incrementWait: "jiaWait" }),
  },
  computed: {
    //借助mapState生成计算属性，从state中读取数据(对象写法)
    ...mapState({
      sum: "sum",
      school: "school",
      subject: "subject",
      personList: "personList",
    }),

    //借助mapState生成计算属性，从state中读取数据(数组写法)
    // ...mapState(['sum','school','subject'])

    ...mapGetters(["bigSum"]),
    // bigSum() {
    //   return this.$store.getters.bigSum;
    // },
  },
};
</script>

<style>
button {
  margin-left: 5px;
}
</style>