数据切换数据目标在边栏中不起作用

Question

我试图从头开始自己设计一个侧边栏是我试过的代码，但它不允许子选项扩展

  

父
     - ＆GT; child1

     

- ＆GT;的child2

<div class=" sidebar" role="navigation">
    <div class="navbar-collapse">
        <nav class="cbp-spmenu cbp-spmenu-vertical cbp-spmenu-left" id="cbp-spmenu-s1">
            <ul class="nav" id="side-menu">
                <li>
                    <a href="index.html" class="active"><i class="fa fa-home nav_icon"></i>Dashboard</a>
                </li>
                <li>
                    <a href="#"><i class="fa fa-book nav_icon"></i>Components<span class="fa arrow"></span></a>
                    <ul class="nav nav-second-level collapse">
                        <li>
                            <a href="grids.html">UpdatePassword</a>
                        </li>
                        <li>
                            <a href="media.html">AddSubject</a>
                        </li>
                    </ul>
                    <!-- /nav-second-level -->
                </li>
                <li>
                    <a href="#"><i class="fa fa-cogs nav_icon"></i>Resources<span class="fa arrow"></span></a>
                    <ul class="nav nav-second-level collapse">
                        <li>
                            <a href="grids.html">ViewResources</a>
                        </li>
                        <li>
                            <a href="media.html">UploadResources</a>
                        </li>
                    </ul>
                    <!-- /nav-second-level -->
                </li>
            </ul>
            <!-- //sidebar-collapse -->
        </nav>
    </div>
</div>