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如何隱藏element-ui中tree懶加載葉子節(jié)點(diǎn)checkbox(分頁(yè)懶加載效果)

更新時(shí)間：2022年07月21日 10:38:56 作者：騎上我心愛(ài)的小摩托

這篇文章主要介紹了如何隱藏element-ui中tree懶加載葉子節(jié)點(diǎn)checkbox(分頁(yè)懶加載效果)，具有很好的參考價(jià)值，希望對(duì)大家有所幫助。如有錯(cuò)誤或未考慮完全的地方，望不吝賜教

根據(jù)最新的工作需求中指示，要求Tree樹(shù)組件為lazy懶加載，且能夠進(jìn)行復(fù)選框選擇，這個(gè)實(shí)現(xiàn)簡(jiǎn)單，設(shè)置show-checkbox即可，若此處要求葉子節(jié)點(diǎn)也不能包含復(fù)選框，就有些困擾了

1.首先按照官網(wǎng)

拷貝tree樹(shù)組件代碼，設(shè)置完show-checkbox，圖中查看更多為葉子節(jié)點(diǎn)，且設(shè)置數(shù)據(jù)節(jié)點(diǎn)屬性為disabled

<el-tree
      ref="treeRef"
      class="treeDom"
      lazy
      show-checkbox
      :props="defaultProps"
      highlight-current="true"
      :load="lazyLoadMore"
      :expand-on-click-node="false"
      :default-expanded-keys="defaultExpandKeys"
      :default-checked-keys="defaultCheckedKeys"
      node-key="id"
      @node-expand="handleNodeExpand"
      @node-collapse="handleNodeCollapse"
      @node-click="handleNodeClick"
      @check="handleCheck"
    >
      <div slot-scope="{ node, data }" class="custom-tree-node">
        <!-- 查看更多 -->
        <span
          v-if="data.id ==='loadmore'"
          class="tree-node loadmore"
          @click="loadMoreNode(node,data)"
        >
          <el-link>{{ node.label }}</el-link>
        </span>
        <!-- 數(shù)據(jù)到底了 -->
        <span
          v-if="data.id ==='disabledload'"
          class="tree-node no-data"
          style="color: #999; cursor: auto;"
        >
          {{ node.label }}
        </span>
        <!-- 普通節(jié)點(diǎn) -->
        <el-tooltip
          class="item"
          effect="light"
          placement="right-start"
        >
          <div slot="content" style="max-width: 300px;">
            {{ node.label }}
          </div>
          <span v-if="data.id !=='loadmore' && data.id!=='disabledload'" class="span-tree-node" @click="loadMoreNode(node,data)">{{ node.label }}</span>
        </el-tooltip>
      </div>
    </el-tree>

css樣式如下：

::v-deep .span-tree-node {
  width: 120px;
  position: absolute;
  text-overflow: ellipsis;
  overflow: hidden;
  color: #696969;
  top: 50%;
  transform: translateY(-50%);
}
::v-deep .treeDom {
  width: 100%;
  overflow-x: auto;
  .custom-tree-node {
    width: 100% !important;
    position: relative;
  }

2.由于屬性是isleaf

所以lazy狀態(tài)下葉子節(jié)點(diǎn)不會(huì)有加載目錄符號(hào)，但此時(shí)，有個(gè)禁用復(fù)選框，現(xiàn)在只需要對(duì)它設(shè)置樣式即可

::v-deep .el-tree .el-tree-node:last-child {
  .el-tree-node__content .is-leaf +.el-checkbox.is-disabled{
    display: none;
  }
  .el-tree-node__content.is-not-clickable{
    cursor: pointer;
  }
}

3. 分頁(yè)懶加載實(shí)現(xiàn)功能也比較簡(jiǎn)單

可以復(fù)寫(xiě)tree樹(shù)自帶的load方法，load方法內(nèi)攜帶兩個(gè)返回參數(shù)，一個(gè)是node，一個(gè)是resolve，即懶加載數(shù)據(jù)必須是通過(guò)resolve就是return 將數(shù)據(jù)帶回

    async lazyLoadMore(node, resolve, parentNode = []) {
      let id = node?.data?.id, pre = node?.data?.name, data = [], arrId = '';
      if (node.level === 0) {
        id = this.paramNode.parent;
        return resolve([{id: id, name: id, leaf: false}]);
      }
      if (node.level === 1) {
        pre = '';
      }
      // 節(jié)點(diǎn)各自的resolve
      this.funcResolve.push({id: id, resolve: resolve});
      this.funcResolve = this.funcResolve.filter((item, index, self)=>{
        return self.findIndex(x=>x.id === item.id) === index;
      });
      // 判斷獲取分頁(yè)查詢的pre參數(shù)
      if (id && id.indexOf('/') > -1) {
        let arrIndex = id.lastIndexOf('/') + 1;
        arrId = id.substring(arrIndex);
        if (arrId === pre) pre = '';
      }
      // lazy加載查詢接口
      const { data: {items} } = await getInterfaceTreeDictory({parent: id || '', pre: pre || ''});
      data = items.map(({interface_url: name, full_interface_url: id}) => {
        return {name, id};
      });
      // 翻頁(yè)信息添加
      if (data.length >= this.pageSize) {
        let nearName = data[data.length - 1].name;
        data.push({name: '查看更多', id: 'loadmore', nearName: nearName, leaf: true, disabled: true});
      }
      // 查看更多加載需根據(jù)各自的resolve加載數(shù)組數(shù)據(jù)
      if (parentNode && parentNode.length > 0) {
        parentNode.push(...data);
        return resolve(parentNode);
      } else {
        return resolve(data);
      }
    },
    // 查看更多事件點(diǎn)擊
    loadMoreNode(node, data) {
      if (data.id === 'loadmore') {
        let nodeParentKey = node.parent.key ? node.parent.key : this.paramNode.parent;
        let childNode = {
            data: {
              id: nodeParentKey,
              name: data.nearName
            }
          }, resolve = '';
        let parentNode = node.parent.childNodes.map(({key: id, label: name})=>{
          return { name, id };
        });
        console.log(parentNode);
        // 剔除自定義查看更多option數(shù)據(jù)
        if (parentNode.length > 0) {
          parentNode = parentNode.slice(0, -1);
        }
        // 選取resolve返回
        if (parentNode.length <= this.pageSize) {
          resolve = this.funcResolve.filter((item)=>{
            return item.id === nodeParentKey;
          });
          // 調(diào)用原生Tree load方法
          this.$refs.treeRef.load(childNode, resolve[0].resolve, parentNode);
        }
      }
    },

代碼內(nèi)有一點(diǎn)需要注意，即每次查詢接口的時(shí)候，和后臺(tái)約定的規(guī)則是：不包含分頁(yè)，需要傳值兩個(gè)參數(shù)，一個(gè)是parent，即當(dāng)前節(jié)點(diǎn)的上一級(jí)所有層級(jí)拼接，另一個(gè)是pre即當(dāng)前節(jié)點(diǎn)的子集，若第一次加載，pre可為空，若查看更多再一次加載pre為上一次加載數(shù)據(jù)data的最后一個(gè)元素id，作為傳參；

eg：