ScopeBar does not appear in UISearchBar when it is active for the first time

I have programmatically created a UISearchController and set the titles of the area buttons in viewDidLoad

UITableViewController *searchResultsController = [[UITableViewController alloc] initWithStyle:UITableViewStylePlain];
searchResultsController.tableView.dataSource = self;
searchResultsController.tableView.delegate = self;
[searchResultsController.tableView registerNib:musicNib forCellReuseIdentifier:@"MusicCell"];

self.searchController = [[UISearchController alloc] initWithSearchResultsController:searchResultsController];
self.searchController.searchResultsUpdater = self;
UISearchBar *searchBar = self.searchController.searchBar;
searchBar.scopeButtonTitles = @[@"Album", @"Artist", @"Song"];
searchBar.showsScopeBar = YES;
searchBar.selectedScopeButtonIndex = 0;
searchBar.delegate = self;

self.tableView.tableHeaderView = self.searchController.searchBar;

      

        
        
        
      

    

But when I go through the search bar while loading the view. the visibility bar is not displayed. The second thing I'm looking for in the search bar is showing the visibility bar. What's happening?