一个简单的例子 vux mutation改变状态

D:\workspace\xxx\src\main.js

引用、注册、定义state、mutations

import Vue from 'vue'
import App from './App'
import VueRouter from 'vue-router'
import Vuex from 'vuex'
import Apple from '@/components/Apple'
import Banana from '@/components/Banana'

Vue.use(VueRouter)
Vue.use(Vuex)

let store = new Vuex.Store({
  state: {
    totalPrice: 0
  },
  mutations: {
    increment (state, price) {
      state.totalPrice += price
    },
    decrement (state, price) {
      state.totalPrice -= price
    }
  }
})

let router = new VueRouter({
  mode: 'history',
  routes: [
    {
      path: '/apple',
      component: Apple
    },
    {
      path: '/banana',
      component: Banana
    }
  ]
})
/* eslint-disable no-new */
new Vue({
  el: '#app',
  router,
  store,
  template: '<App/>',
  components: { App }
})

D:\workspace\xxx\src\App.vue

computed计算并呈现结果（show）

<template>
  <div id="app">
    <img src="./assets/logo.png">
    {{ totalPrice }}
    <Apple></Apple>
    <Banana></Banana>
  </div>
</template>

<script>
import Apple from './components/Apple'
import Banana from './components/Banana'
export default {
  components: { Apple, Banana },
  name: 'App',
  computed: {
    totalPrice () {
      return this.$store.state.totalPrice
    }
  }
}
</script>

<style>
#app {
  font-family: 'Avenir', Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
  margin-top: 60px;
}
</style>

D:\workspace\xxx\src\components\Apple.vue

调用mutations中的方法改变值（set）

<template>
    <div>
      <h1 >{{ msg }}</h1>
      <button @click="addOne">addOne</button>
      <button @click="minusOne">minusOne</button>
      <router-view/>
    </div>
</template>

<script>
export default {
  name: 'Apple',
  data () {
    return {
      msg: 'I am an apple',
      price: 5
    }
  },
  methods: {
    addOne () {
      this.$store.commit('increment', this.price)
    },
    minusOne () {
      this.$store.commit('decrement', this.price)
    }
  }
}
</script>

D:\workspace\xxx\src\components\Banana.vue

<template>
    <div>
      <h3 >{{ mg }}</h3>
      <button @click="addOne">addOne</button>
      <button @click="minusOne">minusOne</button>
    </div>
</template>

<script>
export default {
  name: 'Banana',
  data () {
    return {
      mg: 'I am a banana',
      price: 15
    }
  },
  methods: {
    addOne () {
      return this.$store.commit('increment', this.price)
    },
    minusOne () {
      return this.$store.commit('decrement', this.price)
    }
  }
}
</script>

　　

下图可知，mutations扮演着改变状态的作用（同步）

下文

vux action改变状态