How do I render a single radio button

Using OGNL, it is possible to render a single radio button using the existing radio tag.

<s:radio theme="simple" name="selectedOption" list="{optionA}"/>
...
<s:radio theme="simple" name="selectedOption" list="{optionB}"/>

If you want to use some other (or no) label, you can use a map:

<s:radio theme="simple" name="selectedOption" list="#{optionA:'Value A'}"/>
...
<s:radio theme="simple" name="selectedOption" list="#{optionB:'Value B'}"/>