Prado\Web\UI\WebControls\THiddenField::setValue PHP Method

    public function setValue($value)
    {
        $this->setViewState('Value', $value, '');
    }

 /**
  * Client-side Value property can only be updated after the OnLoad stage.
  * @param string text content for the hidden field
  */
 public function setValue($value)
 {
     if (parent::getValue() === $value) {
         return;
     }
     parent::setValue($value);
     if ($this->getActiveControl()->canUpdateClientSide() && $this->getHasLoadedPostData()) {
         $this->getPage()->getCallbackClient()->setValue($this, $value);
     }
 }