<!-- element plus 树组件实现单选及搜索功能 -->
<template>
    <div class="tree-radio">
        <h3>Element plus 树组件实现单选及搜索功能</h3>
        <hr />
        <el-input
            type="text"
            v-model="filterText"
            placeholder="请输入搜索内容"
        />
        <hr />
        <div class="tree">
            <el-tree
                :data="treeData"
                :props="{
                    label: 'label',
                    children: 'children',
                    class: customNodeClass,
                }"
                node-key="id"
                ref="treeForm"
                show-checkbox
                check-strictly
                default-expand-all
                :filter-node-method="filterNode"
                @check-change="handleCheckChange"
            />
        </div>
        <hr />
        <el-button type="primary" @click="getCheckedTree"
            >获取选中的节点</el-button
        >
    </div>
</template>

<script>
// 给节点添加class
const customNodeClass = (data) => {
    if (data.isPenultimate) {
        return 'no-checkbox-node';
    }
    return null;
};

export default {
    name: 'tree-radio',
    data() {
        return {
            customNodeClass,
            filterText: '',
            checkedId: '',
            treeData: [
                {
                    id: '1',
                    label: '标签1',
                    isPenultimate: true,
                    children: [
                        {
                            id: '1-1',
                            label: '标签1-1',
                        },
                        {
                            id: '1-2',
                            label: '标签1-2',
                        },
                    ],
                },
                {
                    id: '2',
                    label: '标签2',
                    isPenultimate: true,
                    children: [
                        {
                            id: '2-1',
                            label: '标签2-1',
                            isPenultimate: true,
                            children: [
                                {
                                    id: '2-1-1',
                                    label: '标签2-1-1',
                                },
                                {
                                    id: '2-1-2',
                                    label: '标签2-1-2',
                                },
                            ],
                        },
                        {
                            id: '2-2',
                            label: '标签2-2',
                            isPenultimate: true,
                            children: [
                                {
                                    id: '2-2-1',
                                    label: '标签2-2-1',
                                },
                                {
                                    id: '2-2-2',
                                    label: '标签2-2-2',
                                },
                            ],
                        },
                    ],
                },
            ],
        };
    },
    watch: {
        // 过滤操作
        filterText(val) {
            this.$refs.treeForm.filter(val);
        },
    },
    methods: {
        // 过滤节点
        filterNode(value, data) {
            if (!value) return true;
            return data.label.indexOf(value) !== -1;
        },
        // 单选操作
        handleCheckChange(data, checked) {
            if (checked) {
                this.checkedId = data.id;
                this.$refs.treeForm.setCheckedKeys([data.id]);
            } else {
                if (this.checkedId === data.id) {
                    this.$refs.treeForm.setCheckedKeys([data.id]);
                }
            }
        },
        // 获取单选选中的结果
        getCheckedTree() {
            alert(`当前选中的节点为：${this.checkedId}`);
        },
    },
};
</script>

<style lang="less">
// 样式重置，记得把 scoped 属性去掉才能生效
.tree-radio {
    border: 1px solid #ddd;
    padding: 20px;
    border-radius: 5px;
    h3 {
        font-weight: 300;
        color: #ff9b61;
        font-size: 18px;
    }
    width: 500px;
    margin: 100px auto;
    .no-checkbox-node {
        & > .el-tree-node__content {
            .el-checkbox {
                display: none;
            }
        }
    }
    .el-checkbox__inner {
        border-radius: 50%;
    }
}
</style>