<div class="list-group" id="menu">
<a href="#" class="list-group-item" data-toggle="collapse" data-target="#sm" data-parent="#menu">MESSAGES <span class="label label-info">5</span> <span class="glyphicon glyphicon-envelope pull-right"></span></a>
<div id="sm" class="sublinks collapse">
<a class="list-group-item small"><span class="glyphicon glyphicon-chevron-right"></span> inbox</a>
<a class="list-group-item small"><span class="glyphicon glyphicon-chevron-right"></span> sent</a>
</div>
<a href="#" class="list-group-item" data-toggle="collapse" data-target="#sl" data-parent="#menu">TASKS <span class="glyphicon glyphicon-tag pull-right"></span></a>
<div id="sl" class="sublinks collapse">
<a class="list-group-item small"><span class="glyphicon glyphicon-chevron-right"></span> saved tasks</a>
<a class="list-group-item small"><span class="glyphicon glyphicon-chevron-right"></span> add new task</a>
</div>
<a href="#" class="list-group-item">ANOTHER LINK ...<span class="glyphicon glyphicon-stats pull-right"></span></a>
</div>
尽管两者都<a>得到了data-parent="#menu"，但它们都没有出现触发其他隐藏。如何更新此代码以隐藏一个子链接，因为其他子链接可见？