动态创建的下拉菜单未打开

Question

我使用javascript动态创建了下拉菜单，但是当我尝试打开下拉菜单时，它根本没有打开。

这是我动态创建下拉菜单的方式：

$('#contentdiv').append("<div class='ui fluid selection dropdown'><input type='hidden' name='user'/><i class='dropdown icon'></i><div class='default text'>Select Friend/Follower</div><div class='menu' id='menu'>");
                    for(var k=0;k<fflist.length;k++)
                    {
                        $('#menu').append("<div class='item' data-value='"+fflist[k]+"'>"+fflist[k]+"</div>");
                    }
                    $('#contentdiv').append("</div></div>");

Web控制台将元素显示为这样，我找不到任何问题：

<div class="ui fluid selection dropdown">
<input type="hidden" name="user">
<i class="dropdown icon"></i>
<div class="default text">Select Friend/Follower</div>
<div class="menu" id="menu">
<div class="item" data-value="DivyanshuGaur16">DivyanshuGaur16</div>
<div class="item" data-value="akshaykumar">akshaykumar</div>
<div class="item" data-value="aamir_khan">aamir_khan</div>
<div class="item" data-value="SrBachchan">SrBachchan</div>
<div class="item" data-value="UncleOBEY">UncleOBEY</div>
<div class="item" data-value="Waakye_Orgasm">Waakye_Orgasm</div>
<div class="item" data-value="Iamdbeatz">Iamdbeatz</div>
<div class="item" data-value="KwameUltd">KwameUltd</div>
</div>
</div>