JQuery EasyUI combobox动态添加option

<select id="groupType" name="groupType" class="easyui-combobox"  style="width: 170px;" data-options="required:true">
						
</select>

var data,json;
data = [];
data.push({ "text": "全部", "value": 3,"selected":true });
$("#groupType").combobox("loadData", data);