tapestry radio group

I am unable to get the tapestry 4 radio group working.

My HTML

<td><span jwcid="activeServerRadioGroup"></span></td>
<td><input type="radio" jwcid="activeServerRadio" /></td>

My .page

<property name="activeServer"/> 
<component id="activeServerRadioGroup" type="RadioGroup">
         <binding name="selected" value="activeServer.selected"/>
</component>
<component id="activeServers" type="For">
     <binding name="source" value="activeServers"/>
     <binding name="keyExpression" value="literal:id"/>
     <binding name="value" value="activeServer"/>
     <binding name="element" value="literal:tr"/>
</component>
<component id="activeServerRadio" type="Radio">
      <binding name="value" value="activeServer.id"/>
</component> 

In my .java file I have a method getActiveServers() that returns a list of custom class with selected, id attributes. The above structure is not working. Can somebody help?

You did not describe your problem in much detail, but here's my guess:

1. Radio must be put inside a RadioGroup

<span jwcid="activeServerRadioGroup">
  <tr jwcid="activeServers">
    <td><input type="radio" jwcid="activeServerRadio" /></td>
  </tr>
</span>

2. The "selected" parameter of RadioGroup must be set to a server id

<component id="activeServerRadioGroup" type="RadioGroup">
  <binding name="selected" value="activeServerId"/>
</component>

And in your page class:

public ... getActiveServerId()
{
  // Return the id of the active server
}

3. Perhaps you should not even be using RadioGroup?

RadioGroup is only used to select one single object from a list. From your description it sound like you can have several active servers at a time. In that case, perhaps a list of checkboxes would be better?