搜索栏与iOS11上的状态栏重叠

我正在使用UISearchController和UISearchResultsController来实现搜索功能.

MySearchResultsController实现UISearchResultsUpdating和UISearchBarDelegate:

override open func viewDidLoad() {
    super.viewDidLoad()
    self.edgesForExtendedLayout = [];
    self.automaticallyAdjustsScrollViewInsets = false;
}

我在MyTableViewController中像tableHeader一样显示搜索栏:

- (void)viewDidLoad {
    [super viewDidLoad];

    self.searchCOntroller= [[UISearchController alloc] initWithSearchResultsController:self.searchResultsController];
    self.searchController.searchResultsUpdater = self.searchResultsController;
    self.searchController.searchBar.delegate = self.searchResultsController;
    self.searchController.searchBar.scopeButtOnTitles= @[NSLocalizedString(@"SEARCH_SCOPE_TEMPERATURES", nil), NSLocalizedString(@"SEARCH_SCOPE_KNOWHOW", nil)];
    self.tableView.tableHeaderView = self.searchController.searchBar;
    self.definesPresentatiOnContext= YES;
}

这之前完美无缺,但在iOS 11下,一旦我点击它,搜索栏就会与状态栏重叠(见截图).我尝试了很多不同的东西来让它正确显示但还没有找到解决方案.