Vue2 Element封装树形下拉组件

最终效果：

 封装的子组件名字selectTree.vue

<template>
    <el-select :value="valueTitle" :disabled="disabled" :clearable="clearable" @clear="clearHandle">
        <el-option :value="valueTitle" :label="valueTitle">
            <el-tree id="tree-option" ref="selectTree" :accordion="accordion" :data="options" :props="props"
                :node-key="props.value" :default-expanded-keys="defaultExpandedKey" @node-click="handleNodeClick">
            </el-tree>
        </el-option>
    </el-select>
</template>

<script>
export default {
    name: 'ebs-tree-select',
    props: {
        /* 配置项 */
        props: {
            type: Object,
            default: () => {
                return {
                    value: 'id',             // ID字段名
                    label: 'title',         // 显示名称
                    children: 'children'    // 子级字段名
                }
            }
        },
        /* 选项列表数据(树形结构的对象数组) */
        options: {
            type: Array,
            default: () => { return [] }
        },
        /* 初始值 */
        value: {
            type: String,
            default: () => { return null }
        },
        /* 可清空选项 */
        clearable: {
            type: Boolean,
            default: () => { return true }
        },
        /* 自动收起 */
        accordion: {
            type: Boolean,
            default: () => { return false }
        },
        disabled: {
            type: Boolean,
            default: () => { return false }
        }
    },
    data() {
        return {
            valueId: this.value,    // 初始值
            valueTitle: '',
            defaultExpandedKey: []
        }
    },
    mounted() {
        this.initHandle()
    },
    methods: {
        // 初始化值
        initHandle() {
            // alert('this.valueId=' + this.valueId)
            let that = this
            // 这里要延迟执行，否则有BUG
            setTimeout(function () {
                if (that.valueId) {
                    that.valueTitle = that.$refs.selectTree.getNode(that.valueId).data[that.props.label]     // 初始化显示
                    that.$refs.selectTree.setCurrentKey(that.valueId)       // 设置默认选中
                    that.defaultExpandedKey = [that.valueId]      // 设置默认展开
                } else {
                    that.valueTitle = null // 初始化显示
                    that.$refs.selectTree.setCurrentKey(null) // 设置默认选中
                }
            }, 200)
            this.$nextTick(() => {
                let scrollWrap = document.querySelectorAll('.el-scrollbar .el-select-dropdown__wrap')[0]
                let scrollBar = document.querySelectorAll('.el-scrollbar .el-scrollbar__bar')
                scrollWrap.style.cssText = 'margin: 0px; max-height: none; overflow: hidden;'
                scrollBar.forEach(ele => ele.style.width = 0)
            })

        },
        // 切换选项
        handleNodeClick(node) {
            this.valueTitle = node[this.props.label]
            this.valueId = node[this.props.value]
            //this.$emit('getValue',this.valueId)
            this.$emit('input', this.valueId)
            this.defaultExpandedKey = []
        },
        // 清除选中
        clearHandle() {
            this.valueTitle = ''
            this.valueId = null
            this.defaultExpandedKey = []
            this.clearSelected()
            //this.$emit('getValue',null)
            this.$emit('input', null)
        },
        /* 清空选中样式 */
        clearSelected() {
            let allNode = document.querySelectorAll('#tree-option .el-tree-node')
            allNode.forEach((element) => element.classList.remove('is-current'))
        }
    },
    watch: {
        value() {
            this.valueId = this.value
            this.initHandle()
        }
    }
}
</script>

<style scoped>
.el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
    height: auto;
    max-height: 274px;
    padding: 0;
    overflow: hidden;
    overflow-y: auto;
}

.el-select-dropdown__item.selected {
    font-weight: normal;
}

ul li>>>.el-tree .el-tree-node__content {
    height: auto;
    padding: 0 20px;
}

.el-tree-node__label {
    font-weight: normal;
}

.el-tree>>>.is-current .el-tree-node__label {
    color: #409EFF;
    font-weight: 700;
}

.el-tree>>>.is-current .el-tree-node__children .el-tree-node__label {
    color: #606266;
    font-weight: normal;
}
</style>

父组件引用
 

<template>
  <div>
      <!-- 禁用v-bind:disabled="isView" -->
      <selectTree :props="treeSelectProps" v-model="queryParams2.sceneName" :options="catTreeData">
      </selectTree>
                
  </div>
</template>
  
<script>
import selectTree from '../../../components/selectTree/selectTree';

export default {
    name: "Merchant",
    components: {
        selectTree
    },
    data() {
        return {
            treeSelectProps: {
                value: 'key',             // ID字段名
                label: 'sceneName',         // 显示名称
                children: 'children'    // 子级字段名
            },
            catTreeData: [
                {
                    "key": "1462626865326317569",
                    "sceneName": "基础管理",
                    "parentId": "1462626811047829505",
                    "value": null,
                    "code": "B03A01",
                    "children": null,
                    "leaf": true
                },
                {
                    "key": "1462626933466980354",
                    "sceneName": "在线开发",
                    "parentId": "1462626811047829505",
                    "value": null,
                    "code": "B03A02",
                    "children": [
                        {
                            "key": "1462627031668219905",
                            "sceneName": "表单开发",
                            "parentId": "1462626933466980354",
                            "value": null,
                            "code": "B03A02A01",
                            "children": null,
                            "leaf": true
                        },
                        {
                            "key": "1462627069307904002",
                            "sceneName": "报表配置",
                            "parentId": "1462626933466980354",
                            "value": null,
                            "code": "B03A02A02",
                            "children": null,
                            "leaf": true
                        }
                    ],
                    "leaf": false
                }
            ],
    }
};
</script>

<style scoped>
.main-select-el-tree .el-tree-node .is-current>.el-tree-node__content {
    font-weight: bold;
    color: #409eff;
}

.main-select-el-tree .el-tree-node.is-current>.el-tree-node__content {
    font-weight: bold;
    color: #409eff;
}
</style>