Profile: martijnH

add_filter('wpv_filter_query', 'ts_parent_not_private_func', 10, 3);
function ts_parent_not_private_func($query, $view_settings, $view_id) {
  $views = array( 16813, 16403 ); // only filter these views
  if( in_array( $view_id, $views ) ) {
    $child_ids = array(); // we will push IDs here if the parent is not found, or private
    $children_args = array(
      'post_type' => 'training-datum',
      'posts_per_page' => '-1',
      'post_status' => 'publish',
      // you may want to add more filters here to improve the performance of this query
    );
    $children = new WP_Query($children_args);
    foreach( $children->posts as $child ){
      $parent = toolset_get_related_post( $child, 'training_training-datum', 'parent' );
      // if there is no parent or the parent is private, push this ID into the exclusion array
      if( !$parent || get_post_status($parent) == 'private' ){
        array_push( $child_ids, $child->ID );
      }
    }
  
    $query['post__not_in'] = isset( $query['post__not_in'] ) ? $query['post__not_in'] : array();
    $query['post__not_in'] = array_merge($query['post__not_in'], $child_ids );
  }
  return $query;
}