Vue Element UI 树形下拉选择组件 - 优雅的树形数据展示与选择

<template>
  <div class='el-tree-select'>
    <el-select
      style='width: 100%'
      v-model='valueId'
      ref='treeSelect'
      :filterable='true'
      :clearable='true'
      @clear='clearHandle'
      :filter-method='selectFilterData'
      :placeholder='placeholder'
    >
      <el-option :value='valueId' :label='valueTitle'>
        <el-tree
          id='tree-option'
          ref='selectTree'
          :accordion='accordion'
          :data='options'
          :props='objMap'
          :node-key='objMap.value'
          :expand-on-click-node='false'
          :default-expanded-keys='defaultExpandedKey'
          :filter-node-method='filterNode'
          default-expand-all
          @node-click='handleNodeClick'
        ></el-tree>
      </el-option>
    </el-select>
  </div>
</template>
<script setup>

const { proxy } = getCurrentInstance();

const props = defineProps({
  /* 配置项 */
  objMap: {
    type: Object,
    default: () => {
      return {
        value: 'id', // ID字段名
        label: 'label', // 显示名称
        children: 'children' // 子级字段名
      }
    }
  },
  /* 自动收起 */
  accordion: {
    type: Boolean,
    default: () => {
      return false
    }
  },
  /**当前双向数据绑定的值 */
  value: {
    type: [String, Number],
    default: ''
  },
  /**当前的数据 */
  options: {
    type: Array,
    default: () => []
  },
  /**输入框内部的文字 */
  placeholder: {
    type: String,
    default: ''
  }
})

const emit = defineEmits(['update:value']);

const valueId = computed({
  get: () => props.value,
  set: (val) => {
    emit('update:value', val)
  }
});
const valueTitle = ref('');
const defaultExpandedKey = ref([]);

function initHandle() {
  nextTick(() => {
    const selectedValue = valueId.value;
    if(selectedValue !== null && typeof (selectedValue) !== 'undefined') {
      const node = proxy.$refs.selectTree.getNode(selectedValue)
      if (node) {
        valueTitle.value = node.data[props.objMap.label]
        proxy.$refs.selectTree.setCurrentKey(selectedValue) // 设置默认选中
        defaultExpandedKey.value = [selectedValue] // 设置默认展开
      }
    }
    else {
      clearHandle()
    }
  })
}
function handleNodeClick(node) {
  valueTitle.value = node[props.objMap.label]
  valueId.value = node[props.objMap.value];
  defaultExpandedKey.value = [node[props.objMap.value]]; // 设置默认展开
  proxy.$refs.treeSelect.blur()
  selectFilterData('')
}
function selectFilterData(val) {
  proxy.$refs.selectTree.filter(val)
}
function filterNode(value, data) {
  if (!value) return true
  return data[props.objMap['label']].indexOf(value) !== -1
}
function clearHandle() {
  valueTitle.value = ''
  valueId.value = ''
  defaultExpandedKey.value = [];
  clearSelected()
}
function clearSelected() {
  const allNode = document.querySelectorAll('#tree-option .el-tree-node')
  allNode.forEach((element) => element.classList.remove('is-current'))
}

onMounted(() => {
  initHandle()
})

watch(valueId, () => {
  initHandle();
})
</script>