Click the right arrow button to show drop down panel that can be filled with any content.
<div class="easyui-panel" style="width:100%;max-width:400px;padding:30px 60px;">
<div style="margin-bottom:20px">
<input id="cc" style="width:100%;">
</div>
</div>
<div id="sp">
<div style="line-height:22px;background:#fafafa;padding:5px;">
Select a language
</div>
<div style="padding:10px">
<input type="radio" name="lang" value="01"><span>Java</span><br/>
<input type="radio" name="lang" value="02"><span>C#</span><br/>
<input type="radio" name="lang" value="03"><span>Ruby</span><br/>
<input type="radio" name="lang" value="04"><span>Basic</span><br/>
<input type="radio" name="lang" value="05"><span>Fortran</span>
</div>
</div>
<script type="text/javascript">
$(function(){
$('#cc').combo({
required:true,
editable:false,
label:'Language:',
labelPosition:'top'
});
$('#sp').appendTo($('#cc').combo('panel'));
$('#sp input').click(function(){
var v = $(this).val();
var s = $(this).next('span').text();
$('#cc').combo('setValue', v).combo('setText', s).combo('hidePanel');
});
});
</script>