I am having an issue in creating rich:combobox i did as follows
<rich:comboBox selectFirstOnUpdate="false" defaultLabel="Enter some value">
    <f:selectItems value="#{userregister.selectItems}" />
</rich:comboBox>
and in the backing bean i created the selectItems as follows
 List<UISelectItem> selectItems;
 UISelectItem uisi = new UISelectItem();
 uisi.setItemLabel("label");
 uisi.setValue("value");
 selectItems.add(uisi);
But i am getting the exception javax.servlet.ServletException: Value  of tag <selectItems> attribute is incorrect. Which the proper way to create a combobox with dynamic values  ?