SOURCE

// make sure to call Vue.use(Vuex) if using a module system




// 创建一个 Counter 组件
const Counter = {
  template: `<div>{{ count }}</div>`,
  computed: {
    count () {
      return this.$store.state.count
    }
  }
}

new Vue({
  el: '#app2',
  components: { Counter },
  store:new Vuex.Store({
    state: {
      count: 0
    },
    mutations: {
      increment: state => state.count++,
      decrement: state => state.count--
    }
	}),
  methods: {
    increment () {
    console.log(1);
      this.$store.commit('increment')
    },
    decrement () {
    	this.$store.commit('decrement')
    }
  }
})

<div id="app2">
  <counter></counter>
  <p>
    <button @click="increment">+</button>
    <button @click="decrement">-</button>
  </p>
</div>