public static function update($id, $data)
 {
     if (isset($data['eventname']) && empty($data['eventname'])) {
         return print json_encode(array('success' => false, 'status' => 400, 'msg' => 'Activity Name is required'));
     }
     if (isset($data['eventdescription']) && empty($data['eventdescription'])) {
         return print json_encode(array('success' => false, 'status' => 400, 'msg' => 'Start date is required'));
     }
     if (isset($data['eventdate']) && empty($data['eventdate'])) {
         return print json_encode(array('success' => false, 'status' => 400, 'msg' => 'End date is required'));
     }
     EventModel::update($id, $data);
 }