title: How to bind output value into model
body: <p>I've got this binding to the output field:</p>
  
  <pre><code> &lt;xf:bind id="fr-form-binds" ref="instance('fr-form-instance')"&gt;
          &lt;xf:bind id="Pokoj-bind" ref="dok:Pokoj" name="Pokoj" /&gt;
      &lt;/xf:bind&gt;
       &lt;xh:body&gt;
      &lt;xh:td&gt;
        &lt;xf:output id="Pokoj-control" value="concat('Pokój ',xxf:repeat-position())"
                                                 bind="Pokoj-bind"&gt;
           &lt;xf:label ref="$form-resources/Pokoj/label"/&gt;
           &lt;xf:hint ref="$form-resources/Pokoj/hint"/&gt;
           &lt;xf:alert ref="$fr-resources/detail/labels/alert"/&gt;
        &lt;/xf:output&gt;
      &lt;/xh:td&gt;
     &lt;/xh:body&gt;
  </code></pre>
  
  <p>but value of the output it's not saved to the model I would be grateful for any kind of help how to bind value of this to the model.</p>