vue自定义折叠Tree，自定义折叠树

使用组件

<TreeNode v-for="(node, index) in nodes" :key="index" :node="node" />

JSON数据

let nodes=[
    {
        "id": 2030,
        "show_id": "MC1813024492270223360",
        "detail_type": 1,
        "title": "1",
        "description": "",
        "class_hour": 10,
        "children": [
            {
                "id": 2031,
                "show_id": "MC1813024625619734528",
                "detail_type": 1,
                "title": "2",
                "description": "",
                "class_hour": 2,
                "children": [
                    {
                        "id": 1940,
                        "show_id": "MC1813024654644314112",
                        "detail_type": 2,
                        "title": "31",
                        "description": "我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介我是课程视频简介",
                        "class_hour": 0,
                        "children": null,
                        "study_status_str": "未学习",
                        "lesson_number": 0,
                        "level": 3
                    }
                ],
                "study_status_str": "",
                "lesson_number": 0,
                "level": 2
            }
        ],
        "study_status_str": "",
        "lesson_number": 1,
        "level": 1
    }
]

组件

<template>
  <div :style="{ paddingLeft: level * 20 + 'px' }" class="tree-node">
    <div
      @click="toggle"
      class="tree-node-header"
      :class="{ 'first-level': node.level == 1 }"
    >
      <img :src="node.level == 1 ? imgs.group : imgs.dot" alt="" />
      <span class="title">{{ node.title }}</span>
      <template v-if="node.level == 1">
        <span class="class-hour all-hour">总学时 {{ node.class_hour }}</span>
        <span class="class-hour">视频课{{ node.lesson_number }}</span>
      </template>
      <template v-if="!node.children && node.detail_type == 2">
        <span @click="handleClassHour(node)" class="class-hour play"
          ><i class="iconfont">&#xe648;</i>视频课</span
        >
        <!-- <span class="class-hour schedule" >已学习&nbsp;&nbsp;{{ '100%' }}</span> -->
        <span class="class-hour schedule">{{ node.study_status_str }}</span>
      </template>
      <span v-if="hasChildren" class="arrow">
        <i v-show="isOpen" class="el-icon-arrow-up" />
        <i v-show="!isOpen" class="el-icon-arrow-down" />
        <!-- {{ isOpen ? "-" : "+" }} -->
      </span>
    </div>
    <div class="content" v-if="!node.children && node.level != 1">
      {{ node.description }}
    </div>
    <transition name="expand">
      <div v-if="isOpen" class="tree-node-children">
        <TreeNode
          v-for="(child, index) in node.children"
          :key="index"
          :node="child"
          :level="level + 1"
        />
      </div>
    </transition>
  </div>
</template>

<script>
export default {
  name: "TreeNode",
  props: {
    node: {
      type: Object,
      required: true,
    },
    level: {
      type: Number,
      default: 1,
    },
  },
  data() {
    return {
      isOpen: false,
      imgs: {
        group: require("@/pages/web_site_front/resource_manage/pages/onlineCourses/assets/group.png"),
        dot: require("@/pages/web_site_front/resource_manage/pages/onlineCourses/assets/dot.png"),
      },
    };
  },
  computed: {
    hasChildren() {
      return (this.node.children && this.node.children?.length) || 0;
    },
  },
  methods: {
    toggle() {
      if (this.hasChildren) {
        this.isOpen = !this.isOpen;
      }
    },
    handleClassHour(node) {
      document.querySelector(".main-content").scrollTop = 0;
      this.$store.dispatch("user/setCourseVideoId", node.id);
    },
  },
  components: {
    TreeNode: () => import("./treeNode.vue"),
  },
};
</script>

<style scoped lang="scss">
.tree-node {
  margin: 5px 0;
  .tree-node-header {
    cursor: pointer;
    padding: 5px;
    margin-bottom: 16px;
    display: flex;
    font-weight: bold;

    img {
      width: 10px;
      align-self: center;
      margin: 0 5px;
    }
    .title {
      max-width: calc(100% - 160px);
      overflow: hidden;
      white-space: nowrap;
      text-overflow: ellipsis;
    }
    .play {
      font-size: 12px;
      color: #00ab6b;
      line-height: 20px;
      height: 20px;
      border: 0.5px solid #c3e7da;
      border-radius: 4px;
      padding: 0 4px;
      margin-left: 8px;
      display: inline-table;

      i {
        font-size: 14px;
        margin-right: 4px;
      }
    }
    .schedule {
      font-size: 12px;
      color: #00000040;
      margin-left: 8px;
    }
    .arrow {
      flex: 1;
      text-align: right;
      color: #00ab6b;
      margin-right: 31px;
    }
  }
  .first-level {
    height: 40px;
    line-height: 40px;
    display: flex;
    margin-bottom: 16px;
    background: #fafafa;
    border-radius: 8px;
    font-weight: bold;
    font-size: 16px;
    span {
      align-self: center;
    }
    img {
      width: 30px;
      align-self: center;
    }
    .class-hour {
      color: #000000a6;
      line-height: 22px;
      padding: 0 8px;
      background: #f5f5f5;
      border-radius: 2px;
      margin-right: 6px;
      font-size: 14px;
    }
    .all-hour {
      margin-left: 26px;
    }
  }
  .content {
    color: #00000073;
    line-height: 22px;
    border-bottom: 1px solid #f0f0f0;
    padding-bottom: 16px;
    margin-left: 26px;
  }
}

.tree-node-children {
  margin-top: 5px;
  //   border-left: 2px solid #ccc;
  padding-left: 0px;
  .tree-node{
    padding-left: 20px !important;
  }
}

/* Animation Styles */
.expand-enter-active,
.expand-leave-active {
  transition: all 0.3s ease;
}

.expand-enter, .expand-leave-to /* .expand-leave-active in <2.1.8 */ {
  height: 0;
  opacity: 0;
  overflow: hidden;
}
</style>