使用 vue 实例更好的监听事件及vue实例的方法

created () {
 this.$el.addEventListener('click', this.someMethod)
},
destroyed () {
 this.$el.removeEventListener('click', () => this.someMethod)
}

import Vue from 'vue'
const WindowInstanceMap = new Vue({
 data() {
  return {
   scrollY: 0
  }
 },
 created() {
  window.addEventListener('scroll', e => {
   this.scrollY = window.scrollY
  })
 },
})
export default WindowInstanceMap

// AppNav.vue
import WindowInstanceMap from './WindowInstanceMap.js'
export default {
 computed: {
  scrollY () { return WindowInstanceMap.scrollY },
  isCollapsed () {
   return this.scrollY < 100
  }
 }
}