jQuery 展开列表demo效果：

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    * {
      padding: 0;
      margin: 0;
    }
    ul {
      list-style-type: none;
    }
    .parentWrap {
      width: 200px;
      text-align: center;
    }
    .menuGroup {
      border: 1px solid #999;
      background-color: #e0ecff;
    }
    .groupTitle {
      display: block;
      height: 20px;
      line-height: 20px;
      font-size: 16px;
      border-bottom: 1px solid #ccc;
      cursor: pointer;
    }
    .menuGroup > div {
      height: 200px;
      background-color: #fff;
      display: none;
    }
  </style>
  <script src="jquery-3.4.1.js"></script>
  <script>
    $(document).ready(function () {
      $(".groupTitle").click(function () {
        // next()
        // $(this).next().show();
        // parent()
        // $(this).parent().siblings('li').children('div').hide();

        // 合并
        $(this).next().show().parent().siblings('li').children('div').hide();
      })
    })
  </script>
</head>
<body>
  <ul class="parentWrap">
    <li class="menuGroup">
        <span class="groupTitle">标题1</span>
        <div>我是弹出来的div1</div>
    </li>
    <li class="menuGroup">
        <span class="groupTitle">标题2</span>
        <div>我是弹出来的div2</div>
    </li>
    <li class="menuGroup">
        <span class="groupTitle">标题3</span>
        <div>我是弹出来的div3</div>
    </li>
    <li class="menuGroup">
        <span class="groupTitle">标题4</span>
        <div>我是弹出来的div4</div>
    </li>
  </ul>
</body>
</html>
demo 效果：