title: Yii2 - How to add onchange event in activeform
body: <p>This is my code :</p>
  
  <pre><code>&lt;?= $form-&gt;field($model, 'int_roomCatId')
            -&gt;dropDownList(ArrayHelper::map(TblCategory::find()-&gt;all(), 'int_category_id', 'str_category'), array('class' =&gt;'form-control','prompt'=&gt;'Select Room Category'))
            -&gt;label('Room Category');  ?&gt;
  </code></pre>
  
  <p>I want to add onchange = "getData()" event. where to add this?</p>