dosamigos\fileupload\actions\FileListAction::init PHP Method

    public function init()
    {
        if (!isset($this->ownerRelation, $this->ownerTable, $this->searchClass, $this->view)) {
            throw new InvalidConfigException('"searchClass", "ownerRelation", "ownerTable" and "view" attributes cannot be null');
        }
        parent::init();
    }