/**
  * @param Request $request
  * @param Campaign $newsletter
  */
 public function batchDestroy(Request $request, Campaign $newsletter)
 {
     $ids = $request->get('campaigns', []);
     if (is_array($ids) && count($ids)) {
         $newsletters = $newsletter->whereIn('newsletter_campaigns.id', $ids)->get();
         foreach ($newsletters as $newsletter) {
             $newsletter->delete();
         }
     }
 }