Swift谷歌地图自动建议下拉式造型

Question

我正在使用GMSAutocompleteResultsViewController来自动建议地址。我该怎么样呢？比如缩小字体大小和改变背景等

这是代码

resultsViewController = GMSAutocompleteResultsViewController()
        resultsViewController?.delegate = self


        searchController = UISearchController(searchResultsController: resultsViewController)
        searchController?.searchResultsUpdater = resultsViewController
        searchController?.searchBar.sizeToFit()
        self.navigationItem.titleView = searchController?.searchBar