public function __construct()
 {
     parent::__construct();
     $where = array('order_by' => 'channel_title', 'sort' => 'asc');
     $channels = array('' => '');
     foreach ($this->channel_data->get_channels($where)->result() as $channel) {
         $channels[$channel->channel_id] = $channel->channel_title;
     }
     $this->fields['channel_id']['settings']['options'] = $channels;
 }
 public function __construct()
 {
     parent::__construct();
 }