The linkage method between menu and tab of vue+iview

<template>
  <div>
    <Select v-model="whereMap.model1"
            style="width:200px"
            @on-change="getSecond">
      <Option v-for="item in list1"
              :value="item.id"
              :key="item.id">{{ item.label }}</Option>
    </Select>
    <Select v-model="whereMap.model2"
            style="width:200px"
            @on-change="getThird">
      <Option v-for="item in list2"
              :value="item.id"
              :key="item.id">{{ item.label }}</Option>
    </Select>
    <Select v-model="whereMap.model3"
            style="width:200px">
      <Option v-for="item in list3"
              :value="item.id"
              :key="item.id">{{ item.label }}</Option>
    </Select>
    <Button class="search-btn"
            type="default"
            @click="searchClear">Clear</Button></div>
</template>
<script>
export default {
  data () {
    return {
      datatest: {
        l1: [
          {
            id: 'cat',
            label: 'cat'
          },
          {
            id: 'dog',
            label: 'dog'
          }
        ],
        l2: {
          cat: [{ id: 'sc', label: 'Kitten' }, { id: 'bc', label: 'Big cat' }],
          dog: [{ id: 'sd', label: 'Puppy' }, { id: 'bd', label: 'Big dog' }]
        },
        l3: {
          sc: [{ id: 'sc1', label: 'Little cat' }, { id: 'sc2', label: 'Little orange cat' }],
          bc: [{ id: 'bc1', label: 'Big tabby cat' }, { id: 'bc2', label: 'Big orange cat' }]
        }
      },
      list1: [],
      list2: [],
      list3: [],
      whereMap: {
        model1: '',
        model2: '',
        model3: ''
      }
    }
  },
  mounted () { this.init() },
  created () {
    this.init()
  },
  methods: {
    init () {
      this.list1 = this.datatest.l1
    },
    getSecond(val) {
      this.list2 = this.datatest.l2[val]
    },
    getThird (val) {
 
      this.list3 = this.datatest.l3[val]
    },
    searchClear () {
      console.log(this.whereMap)
      this.whereMap = {};
      this.list2 = [];
      this.list3 = [];
    }
  }
}
</script>