<template>
 <div class="vue-dropdown default-theme">
 <div class="cur-name" :class="isShow " @click="isShow =! isShow">{{itemlist.cur.name}}</div>
 <div class="list-and-search" :class="isShow">
 <div class="search-module clearfix" v-show="isNeedSearch">
  <input class="search-text" 
  @keyup='search($event)' :placeholder="placeholder" />
  </div>
  <ul class="list-module">
  <li v-for ="(item,index) in datalist" @click="selectToggle(item)" 
  :key="index">
   <span class="list-item-text">{{item.name}}</span>
  </li>
  </ul>
  <div class="tip-nodata" v-show="isNeedSearch && datalist.length == 0">{{nodatatext}}</div>
 </div>
 </div>
</template>

<script>
 export default {
 data(){
  return {
  datalist:[],
  isShow:false
  }
 },
 props:{
  'itemlist':Object,//父组件传来的数据
  'placeholder':{
  type:String,
  default: '搜索' //input placeholder的默认值
  },
  'isNeedSearch':{ //是否需要搜索框
  type:Boolean,
  default: false
  },
  'nodatatext':{ 
  type:String,
  default: '未找到结果' //没有搜索到时的文本提示
  } 
 },
 created(){
  this.datalist = this.itemlist.data;
  //点击组件以外的地方，收起
  document.addEventListener('click', (e) => {
  if (!this.$el.contains(e.target)){
   this.isShow = false; 
  }
  }, false)
 },
 methods:{
  selectToggle(data){
  this.itemlist.cur.name = data.name;
  this.isShow = false;
  this.$emit('item-click',data);
  },
  search(e){
  let searchvalue = e.currentTarget.value;
  this.datalist = this.itemlist.data.filter((item,index,arr)=>{
   return item.name.indexOf(searchvalue) != -1;
  });
  }
 }
 }
</script>

<style lang="less" scoped>
 .list-and-search{
 background: #fff;
 border: 1px solid #ccc;
 display: none;
 &.on{
  display: block;
 }
 }
 .cur-name{
 height: 32px;
 line-height: 32px;
 text-indent: 10px;
 position: relative;
 color: #777;
 &:after{
 position: absolute;
 right: 9px;
 top: 13px;
 content: " ";
 width: 0;
 height: 0;
 border-right: 6px solid transparent;
 border-top: 6px solid #7b7b7b;
 border-left: 6px solid transparent;
 border-bottom: 6px solid transparent;
 }
 &.show{
 &:after{
 right: 9px;
 top: 6px;
 border-right: 6px solid transparent;
 border-bottom: 6px solid #7b7b7b;
 border-left: 6px solid transparent;
 border-top: 6px solid transparent;
 }
 }
 }
 .vue-dropdown.default-theme {
 width: 200px;
 z-index:10;
 border-radius:3px; 
 border: 1px solid #ccc;
 cursor: pointer;
 -webkit-user-select:none; 
 user-select:none;
 &._self-show {
  display: block!important;
 }
 .search-module {
  position: relative;
  border-bottom: 1px solid #ccc;
  .search-text {
  width: 100%;
  height: 30px;
  text-indent: 10px;
  // border-radius: 0.5em;
  box-shadow: none;
  outline: none;
  border: none;
  // &:focus {
  // border-color: #2198f2;
  // }
  }
  .search-icon {
  position: absolute;
  top: 24%;
  right: 0.5em;
  color: #aaa;
  }
 }
 input::-webkit-input-placeholder{
  font-size: 14px;
 }
 .list-module {
  max-height: 200px;
  overflow-y: auto;
  li {
  &._self-hide {
   display: none;
  }
  margin-top: 0.4em;
  padding: 0.4em;
  &:hover {
   cursor:pointer;
   color: #fff;
   background: #00a0e9;
  }
  }
 }
 }
 .tip-nodata {
 font-size: 14px;
 padding: 10px 0;
 text-indent: 10px;
 }
</style>

<dropdown :item-click="dropDownClick" :isNeedSearch="true" :itemlist="itemlist"></dropdown>

import Dropdown from '@/components/dropdown.vue'
export default {
 data() {
 return {
 itemlist: {
 cur: {
  val: "",
  name: "所有产品"
 },
 data: [{
  val: "",
  name: "所有产品"
 }, {
  val: 1,
  name: "梦幻西游"
 }, {
  val: 2,
  name: "梦幻无双"
 }, {
  val: 3,
  name: "大话西游"
 }]
 },
 }
 },
 components: {
 Dropdown,
 },
 methods :{
 dropDownClick(e) {
 console.log(e.name, e.val)
 }
 }
}

<template>
 <div class="vue-dropdown default-theme" v-show-extend="show">
  <div class="search-module clearfix" v-show="itemlist.length">
   <input class="search-text" 
   @keyup='search($event)' :placeholder="placeholder" />
   <span class="glyphicon glyphicon-search search-icon"></span>
  </div>
  <ul class="list-module" v-show="length">
   <li v-for ="(item,index) in datalist" @click="appClick(item)" 
   :key="index">
    <span class="list-item-text">{{item.name}}</span>
   </li>
  </ul>
  <div class="tip__nodata" v-show="!length">{{nodatatext}}</div>
 </div>
</template>

<script>
 export default {
  data(){
   return {
    datalist:[]
   }
  },
  props:{
   'show':{//用于外部控制组件的显示/隐藏
    type:Boolean,
    default:true
   },
   'itemlist':Array,
   'placeholder':String,
   'nodatatext':String
  },
  watch:{
   itemlist:function(val){
    this.datalist = val.concat();
   }
  },
  directives:{
   'show-extend':function(el,binding,vnode){//bind和 update钩子
    let value = binding.value,searchInput = null;
    if(value){
     el.style.display='block';
    }else{//隐藏后，恢复初始状态
     el.style.display='none';
     searchInput = el.querySelector(".search-text");
     searchInput.value = '';
     vnode.context.datalist = vnode.context.itemlist;//还原渲染数据
    }
   }
  },
  methods:{
   appClick:function(data){
    this.$emit('item-click',data);
   },
   search:function(e){
    let vm = this,searchvalue = e.currentTarget.value;
    vm.datalist = vm.itemlist.filter(function(item,index,arr){
     return item.name.indexOf(searchvalue) != -1;
    });
   }
  },
  computed:{
   length:function(){
    return this.datalist.length;
   }
  }
 }
</script>

<style lang="scss" scoped>
 .vue-dropdown.default-theme {
  position: absolute;
  left:15%;
  display: none;
  width: 70%;
  margin: 0 auto;
  margin-top: 1em;
  padding: 1em;
  z-index:10;
  box-shadow: 0px 0px 10px #ccc;
  &._self-show {
   display: block!important;
  }

  .search-module {
   position: relative;
   .search-text {
    width: 100%;
    height: 30px;
    padding-right: 2em;
    padding-left:0.5em;
    border-radius: 0.5em;
    box-shadow: none;
    border: 1px solid #ccc;

    &:focus {
     border-color: #2198f2;
    }
   }

   .search-icon {
    position: absolute;
    top: 24%;
    right: 0.5em;
    color: #aaa;
   }

  }

  .list-module {
   max-height: 200px;
   overflow-y: auto;
   li {
    &._self-hide {
     display: none;
    }
    margin-top: 0.5em;
    padding: 0.5em;
    &:hover {
     cursor:pointer;
     color: #fff;
     background: #00a0e9;

    }
   }
  }
 }
 .tip__nodata {
  font-size: 12px;
  margin-top: 1em;
 }
</style>

<dropdown :itemlist="itemlist" :placeholder="placeholder" 
:nodatatext="nodatatext"></dropdown>