ElementUI实现在下拉列表里面进行搜索功能详解

分析:

1. 首先我们需要实现上图的效果,然后Element-UI的el-select是没有的,所以需要自己写
2. 我们需要用到el-popover组件,然后使用它的v-model="visible"来实现控制显示
3. 我们在el-popover的slot="reference" 放一个el-select
   1. 使用popper-append-to-body="false"不需要插入浮动元素
   2. 使用popper-class="hide-popper"定义浮窗class为hide-popper,并设置display:none,这样选中了就不会存在el-select的下拉选项
   3. el-option 循环下面选择的list里面的元素,这样就可以在el-select展示选中的并存在删除
   4. el-select双向绑定的就是自定义选择的数组

html:

<template>
	<div class="arrbox">
		<!-- 通过visible控制显示还是隐藏 -->
		<el-popover
		v-model="visible"
		placement="bottom-start"
		width="auto"
		>
		<div slot="reference" class="check-select">
			<!-- popper-append-to-body:不需要插入浮动元素,popper-class:设置类名并隐藏 -->
			<el-select
			ref="select"
			v-model="currentval"
			:style="{width:`${width}px`,height:`${height}`}"
			multiple
			:placeholder="placeholder"
			:popper-append-to-body="false"
			popper-class="hide-popper"
			style="width:100%"
			@visible-change="visibleChange"
			@focus="getFocus"
			> <el-option
			v-for="item in selectItem"
			:key="`${item.value}_k`"
			:label="item.label"
			:value="item.value"
			/></el-select>
		</div>
		<!-- selectBxClick让select强制选中 -->
		<div class="selectMain" :style="{'min-width':`${width-20}px`}" @click="selectBxClick">
			<div class="seachButton">
			<el-select
				v-model="seachValue"
				placeholder=" 请选择筛选"
				style="width:70%;margin-right:10px;max-width:195px"
				@visible-change="selectBxClick()"
			>
				<el-option
				v-for="item in seachList"
				:key="item.value"
				:value="item.value"
				:label="item.label"
				/>
			</el-select>
			<div class="btn" @click="seachBtn">搜索</div>
			</div>
			 <div class="selectDiv">
  <div v-for="item in list.filter(n=>n.value=='all')" :key="item.value" class="list" :class="[currentval.indexOf(item.value)!=-1?'selected':'',item.value=='all'?'allCheck':'']" @click="clickItem(item)">{{ item.label }}</div>

  <div class="selectDivAuto">
<div v-for="item in list.filter(n=>n.value!='all')" :key="item.value" class="list" :class="[currentval.indexOf(item.value)!=-1?'selected':'',item.value=='all'?'allCheck':'']" @click="clickItem(item)">{{ item.label }}</div>
  </div>

</div>
		</div>
		</el-popover>
	</div>
	</template>

js:

使用getFocus获取是否聚焦,聚焦了让visible=true,这样就可以显示出自定义的下拉选择项

通过visibleChange实施监听el-select,控制el-popover显示

在点击自定义的下拉选择项时,通过@click="selectBxClick"让el-select一直聚焦,这样箭头就会一直向上

通过 @click="seachBtn"和getList获取列表,具体需要自己去自定义

// 模拟获取的数据
	const seachClickList = [{value: '1',label: '测试1',type: '1'},{value: '2',label: '测试2',type: '1'},{value: '3',label: '测试3',type: '1'},{value: '4',label: '测试4',type: '2'},{value: '5',label: '测试5',type: '2'},{value: '6',label: '测试6',type: '2'},{value: '7',label: '测试7',type: '2'}]
	export default {
	model: {
		prop: 'parentArr',
		event: 'change-parentArr'
	},
	props: {
		parentArr: {
		type: Array,
		default() {
			return []
		}
		},
		// 传入选中的item,主要时防止list里面没有选中的数据
		parentSelectItem: {
		type: Array,
		default() {
			return []
		}
		},
		width: {
		type: Number,
		default: 300
		},
		height: {
		type: Number,
		default: 30
		},
		placeholder: {
		type: String,
		default: '请输入'
		}
	},
	data() {
		return {
		seachList: [
			{
			value: '1',
			label: '条件一'
			},
			{
			value: '2',
			label: '条件二'
			}
		],
		visible: false,
		currentval: [],
		list: [],
		selectItem: [],
		seachValue: '1'
		}
	},
	watch: {
		seachValue: {
		handler(value) {
			this.getList(value)
		},
		deep: true,
		immediate: true
		},
		parentArr: {
		handler(value) {
			this.currentval = value
		},
		deep: true,
		immediate: true
		},
		parentSelectItem: {
		handler(value) {
			this.selectItem =  value.map(n => {
  if (n.value == 'all') {
n.label = '全部'
  }
  return n
})
		},
		deep: true,
		immediate: true
		},
		currentval: {
handler(value) {
this.$emit('change-parentArr', value)
}
		}
	},
	created() {
	},
	methods: {
		getList(value) {
this.list = [{
label: '全部',
value: 'all'
}, ...seachClickList.filter(n => n.type == value)]
this.getSelectItem()
		},
		// 获取选中的item
		getSelectItem() {
const noItemList = this.currentval.map(n => {
if (this.selectItem.findIndex(i => i.value == n) == -1) {
return n
}
return null
}).filter(n => n != null)
noItemList.forEach(item => {
const index = this.list.findIndex(i => i.value == item)
if (index != -1) {
this.selectItem.push(this.list[index])
}
})
		},
		getFocus() {
this.visible = true
		},
		visibleChange(data) {
this.visible = data
		},
		selectBxClick() {
// 避免点击框体时组件消失
this.$refs.select.visible = true
		},
		// 选择
		clickItem(item) {
  const index = this.currentval.indexOf(item.value)
  if (index == -1) {
if (item.value == 'all') {
  this.currentval = ['all']
  this.selectItem = [{
label: '全部',
value: 'all'
  }]
} else {
  this.currentval.push(item.value)
  this.selectItem.push(item)
  const currentvalIndex = this.currentval.indexOf('all')
  const selectItemIndex = this.selectItem.findIndex(n => n.value == 'all')
  if (currentvalIndex != -1 && selectItemIndex != -1) {
this.selectItem.splice(selectItemIndex, 1)
this.currentval.splice(currentvalIndex, 1)
  }
}
  } else {
const itemIndex = this.selectItem.findIndex(n => n.value == item.value)
this.selectItem.splice(itemIndex, 1)
this.currentval.splice(index, 1)
  }
},
		// 搜索
		seachBtn() {
this.getList()
		}
	}
	}

css:

selected属性使用了el-select的样式,让样子尽量一致

.arrbox {
display: inline-block;
}
.check-select{
::v-deep.hide-popper{
	display: none;
}
}
::v-deep .el-input__suffix{
i:not(.el-select__caret){
	display: none;
}
}
.selectMain {
width: 100%;
height: 100%;
.seachButton{
	width: 100%;
	align-items: center;
	display: flex;
	div.btn{
	width: 25%;
	max-width: 70px;
	max-width: 80px;
	height: 40px;
	display: flex;
	align-items: center;
	justify-content: center;
	font-size: 12px;
	color: #fff;
	background-color: #409EFF;
	border-radius: 5px;
	cursor: pointer;
	}
}
.selectDiv{
width: 100%;
max-width: 500px;
margin-top: 10px;
padding:  0 10px 0 0;
.list{
  width: 100%;
  padding: 10px 20px 10px 10px;
  color: #666;
  cursor: pointer;
  position: relative;
  &.selected{
color: #409EFF;
&::after{
  position: absolute;
  right: 0px;
  top: 50%;
  transform: translateY(-50%);
  font-family: element-icons;
  content: "\e6da";
  font-size: 12px;
  font-weight: 700;
  -webkit-font-smoothing: antialiased;
}
  }
}
.selectDivAuto{
  width: calc(100% + 15px);
  max-height: 300px;
  overflow-y: auto;
  .list{
padding: 10px 30px 10px 10px;
&.selected::after{
  right: 10px;
}
  }
}

  }
}
.allCheck{
border-bottom: 1px solid rgb(228, 225, 225);
}

使用

<template>
	<seachSelectInput v-model="from.tag" :parentSelectItem='selectItem' :width="302" placeholder="请选择标签" />
</template>
<script>
import seachSelectInput from ./seachSelectInput'
export default {
components: {
	seachSelectInput
},
data(){
	return{
		from:{
			tag:['1']
		},
		selectItem:[
			{
			value: '1',
			label: '测试1'
			}
		]
	}
}
}