title: how to add class inside checkbox and label field
body: <p>i want to implement this html code into yii format.</p>
  
  <pre><code>&lt;input type="checkbox" name="" class="checkbox1" onclick="" id=""/&gt;
  &lt;label class="gender" for="" id=""&gt;Female&lt;/label&gt;
  </code></pre>
  
  <p>i tried to implement this code.</p>
  
  <pre><code>$form-&gt;checkBox($model,'gender',array('class'=&gt;'gen'),array('template'=&gt;'{label}')
  </code></pre>
  
  <p>but i don't know how to assign <strong>gender</strong> css class to label field? could please suggest me how to implement above html code in right way.</p>