iView的Select选择框清空

<template>
    <Select v-model="model8" ref="resetSelect" clearable>
        <Option v-for="item in cityList" :value="item.value" :key="item.value">{{ item.label }}Option>
    Select>
    <Button class="search-btn" type="primary">搜索Button>
    <Button class="search-btn" type="default" @click="searchClear">清空Button>
template>

<script>
    export default {
        data () {
            return {
                cityList: [
                    {
                        value: 'New York',
                        label: 'New York'
                    },
                    {
                        value: 'London',
                        label: 'London'
                    }
                ]
            }
        },
        methods: {
        	searchClear() {
        		this.$refs.resetSelect.clearSingleSelect();
        		//或 this.$refs['resetSelect'].clearSingleSelect();
        		//或 this.$refs.resetSelect.query = '';
        	}
        }
    }
script>