title: Yii2 date formatter not working in active form
body: <p>I setup in config file date format as :</p>
  
  <pre><code>'dateFormat' =&gt; 'yy-MM-dd',
  </code></pre>
  
  <p>but I can't find the way to get dates in this format in active form :
  I tried :</p>
  
  <pre><code>&lt;?= $form-&gt;field($model,
      'mydate':date,
  </code></pre>
  
  <p>but this gives error
  Any help would be nice :)</p>