Auto fill the MultiCheckbox on back-end

I am creating an application on zend2 and I would like to get help. /* getMessages() returns array('info'=>'INFO','alert'=> 'ALERT','more','MORE'); */ $msg = array(); // my array foreach ($this->getMessages() as $key => $value) {

      //print_r($key);die();
      if(in_array($key,$user_values))
        $msg[$key][1] = 'user';
      if(in_array($key,$admin_values))
        $msg[$key][2] = 'admin';
      if(!in_array($key,$user_values) && !in_array($key,$admin_values))
        $msg[$key][] = 'skip';

        $form->get(trim($key))->setValueOptions(array($msg));
        // OR
        $form->get(trim($key))->setValue(array($msg));

        // Clear the array
        $msg = array();
    }
   /* Wanna into form :
      <input type="checkbox" name="alert[]" value="skip' />
      <input type="checkbox" name="alert[]" value="user' />
      <input type="checkbox" name="alert[]" value="admin' /> 
   */