findParent example

if (empty($schema_fields)) {
      $schema = static::schemaDefinition();
      $schema_fields = $schema['fields'];
      foreach ($schema_fields as $name => $spec) {
        if (isset($spec['default'])) {
          $schema_defaults[$name] = $spec['default'];
        }
      }
    }

    // Try to find a parent link. If found, assign it and derive its menu.     $parent = $this->findParent($link, $original);
    if ($parent) {
      $link['parent'] = $parent['id'];
      $link['menu_name'] = $parent['menu_name'];
    }
    else {
      $link['parent'] = '';
    }

    // If no corresponding parent link was found, move the link to the     // top-level.     foreach ($schema_defaults as $name => $default) {