vue组件实现可搜索下拉框扩展

<template>
  <div class="vue-dropdown-ext" :class="themestyle" v-show-extend="show">
    <div class="search-module clearfix" v-show="itemlist.length">
      <input class="search-text" @keyup='search($event)' 
      :placeholder="placeholder" />
      <span class="glyphicon glyphicon-search search-icon"></span>
    </div>
    <ul class="list-module" v-show="length" :style="{maxHeight:maxH+'px'}">
      <li v-for ="(item,index) in datalist" @click="appClick(item,$event)" 
      :key="index" :title="item.name">
        <span v-if="addIcon" :class="iconClass"></span>
        :style="itemTextStyle">{{item.name}}</span>
        <span v-if="statusIconType == 'text' && hasStatus" 
        :class="item.statusClass">{{item.statusText}}</span>
         :class="item.statusClass"></span>
      </li>
    </ul>
    <div class="tip__nodata" v-show="!length&&itemlist.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,
      'themestyle':{
        type:String,
        default:'default-theme'
      },
      'item-text-style':{
        type:Object,
        default:function(){
          return {
            width:'80%'
          }
        }
      },
      'add-icon':{
        type:Boolean,
        default:true
      },
      'icon-class':{
        type:String,
        default:''
      },
      'has-status':{
        type:Boolean,
        default:false
      },
      'status-icon-type':{
        type:String,
        default:'text'//text or icon
      },
      'max-h':{
        type:Number,
        default:$(window).height()-400
      }
    },
    watch:{
      itemlist:function(val){
        this.datalist = val.concat();
      }
    },
    directives:{
      'show-extend':function(el,binding,vnode){//bind和 update钩子
        let value = binding.value,searchInput = null;
        if(value){
          el.style.display='block';
        }else{//隐藏后，恢复初始状态
          el.style.display='none';
          searchInput = el.querySelector(".search-text");
          searchInput.value = '';
          //还原渲染数据
          vnode.context.datalist = vnode.context.itemlist;
        }
      }
    },
    methods:{
      appClick:function(data,event){
        this.$emit('item-click',data,event);
      },
      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;
        });
      },
      statusIconClass:function(status){
        let statusClass = '';
        return statusClass;
      }
    },
    computed:{
      length:function(){
        return this.datalist.length;
      }
    }
  }
</script>

<style lang="scss" scoped>
  .text-overflow__style {
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
  }
  .vue-dropdown-ext {

    .search-module { position: relative;
      .search-text { width: 100%;
        height: 30px;
        padding-right: 2em;
        padding-left:0.5em;
        box-shadow: none;
        border: 1px solid #ccc;
        background: #fff;
        &:focus { border-color: #2198f2;
        }
      }

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

    }

    .list-module {
      overflow: auto;
      li { position: relative;
        margin-top: 0.5em;
        padding: 0.5em;
        border: 1px solid #ccc;
        white-space: nowrap;

        &>span { display: inline-block;
          vertical-align: middle;
        }

      }
    }

    .tip__nodata {
      font-size: 12px;
      margin-top: 1em;
    }

    &.default-theme {
      .list-module li { &:hover { cursor: pointer;
          border-color: #00a0e9;
        }

        &.active {
          border-color: #00a0e9;
          color: #00a0e9;
        }
      }

    }
  }
</style>