Vuex配置

1. state.js，存放的是状态

const state = {
// 数据存放
  singer: null
}
export default state

2. mutation-types.js，定义mutation的常量

export const SET_SINGER = 'SET_SINGER'

3. mutations，改变state状态，只能通过mutations来改变state，这里是同步执行

import * as types from './mutation-types'

const mutations = {
  // 第一个参数是状态state，第二个参数是组件传来的数据
  [types.SET_SINGER] (state, singer) {
    state.singer = singer
  }
}
export default mutations

4. actions.js 异步

5. index.js 导出

import Vue from 'vue'
import Vuex from 'vuex'
import state from './state'
import mutations from './mutations'
import * as getters from './getters'
import actions from './actions'
// 控制台可以打印出state状态变化的前后值，便于跟踪状态变化
import createLogger from 'vuex/dist/logger'

Vue.use(Vuex)
// 通过debug开启strict严格模式，自动检测vuex操作是否正确
const debug = process.env.NODE_ENV !== 'production'
export default new Vuex.Store({
    state,
    actions,
    mutations,
    getters,
    strict: debug,
    plugins: debug ? [createLogger()] : []
  }
)