bootstrap二级下拉多选

<div class="col-sm-8">
<select id="slpk" class="selectpicker" name="roleIdList" data-live-search="true" data-live-search-placeholder="Search" data-actions-box="true"
multiple>
<c:forEach items="${rolesGroup}" var="obj">
<optgroup label="${obj.name}">
<c:forEach items="${obj.roleList}" var="roleList">
<option value="${roleList.id}">${roleList.name}</option>
</c:forEach>
</optgroup>
</c:forEach>
</select>

</div>

$(function() {/*初始化函数*/
$(".selectpicker").selectpicker({
noneSelectedText : '请选择'//默认显示内容  

});

});