Vue下拉菜单点击收起失效：从blur到mousedown的事件顺序排查

<template lang="html">
<div :class="[baseClass + '-wrap']">
 <input
  type="text"
  v-model="searchVal"
  :class="[baseClass + '-input']"
  ref="demo-search-input"
  placeholder="搜索"
  @focus="onFoucs"
  @blur="onBlur"
  @keyup.enter="onSearch"
  @input="getRecommendedList" />
 <span :class="[baseClass + '-btn']" @click="onSearch"></span>
 <div :class="[baseClass + '-recommended']" v-show="isShowRecommend && recommendList.length > 0">
  <div :class="[baseClass + '-triangle-border', baseClass + '-tb-border']"></div>
  <div :class="[baseClass + '-triangle-border', baseClass + '-tb-bg']"></div>
  <ul :class="[baseClass + '-list-wrap']">
   <li
    :class="[baseClass + '-list']"
    v-for="(item, index) in recommendList"
    :key="index"
    @click="onSearch(item)"
   >{{item}}</li>
  </ul>
 </div>
</div>
</template>

<script>
const mockData = ['123456', '12', '56873', '092341', '454666677']
export default {
 data () {
  return {
   baseClass: 'demo-search',
   searchVal: '',
   isShowRecommend: false,
   recommendList: []
  }
 },
 methods: {
  onFoucs () {
   this.isShowRecommend = true
  },
  onBlur () {
   this.isShowRecommend = false
   this.searchVal = ''
   this.recommendList = []
  },
  onSearch (val) {
   val = typeof val === 'string' ? val : this.searchVal
   if (val) {
    // 这里需要跳转搜索，我们用console来代替
    console.log(val)
    this.searchVal = ''
   } else {
    this.$refs['demo-search-input'].focus()
   }
  },
  getRecommendedList () {
   if (this.searchVal) {
    // 这里需要给后台发送请求来获取联想词，这里我们用mock数据匹配来展示
    setTimeout(() => {
     const reg = new RegExp(this.searchVal)
     const arr = []
     for (let i = 0; i < mockData.length; i++) {
      if (reg.test(mockData[i])) {
       arr.push(mockData[i])
      }
     }
     this.recommendList = arr
    }, 10)
   }
  }
 }
}
</script>

onBlur () {
 setTimeout(() => {
  this.isShowRecommend = false
  this.searchVal = ''
  this.recommendList = []
 }, 500)
}

methods: {
  onClick () {
   console.log('click')
  },
  onMousedown () {
   console.log('mousedown')
  },
  onMouseup () {
   console.log('mouseup')
  },
  onBlur () {
   console.log('blur')
  }
}

<li
 :class="[baseClass + '-list']"
 v-for="(item, index) in recommendList"
 :key="index"
 @mousedown="onSearch(item)"
>{{item}}</li>