在XLPagerTabStrip视图上使用UISearchBar显示视图

Question

我的应用程序中有一个搜索视图，该视图可以正常工作。我需要更新搜索视图，以便在搜索栏为空时视图显示搜索类别。

如何在XLPagerTabStrip控制器上显示视图，同时仍将搜索栏保持在适当的位置？

class SearchViewController: ButtonBarPagerTabStripViewController, UISearchBarDelegate{

    var businesses = [Business]()
    var coupons = [Coupon]()

    var businessSearchVC: BusinessSearchViewController?
    var couponSearchVC: CouponSearchViewController?

    lazy var searchBar: UISearchBar = {
        let sb = UISearchBar()
        sb.placeholder = "Search businesses or coupons"
        sb.barTintColor = .gray
        UITextField.appearance(whenContainedInInstancesOf: [UISearchBar.self]).backgroundColor = UIColor.mainWhite()
        sb.delegate = self
        return sb
    }()

    override func viewDidLoad() {

        settings.style.buttonBarItemBackgroundColor = .clear
        settings.style.selectedBarBackgroundColor = .mainGreen()
        settings.style.selectedBarHeight = 4.0
        settings.style.buttonBarMinimumLineSpacing = 0
        settings.style.buttonBarItemsShouldFillAvailableWidth = true
        settings.style.buttonBarLeftContentInset = 0
        settings.style.buttonBarRightContentInset = 0
        settings.style.selectedBarHeight = CGFloat(5)

        super.viewDidLoad()

        view.backgroundColor = .white

        self.navigationItem.titleView = searchBar

    }

    override func viewControllers(for pagerTabStripController: PagerTabStripViewController) -> [UIViewController] {
        businessSearchVC = BusinessSearchViewController(collectionViewLayout: UICollectionViewFlowLayout(), businesses: businesses)
        couponSearchVC = CouponSearchViewController(collectionViewLayout: UICollectionViewFlowLayout(), coupons: coupons)
        return [businessSearchVC!, couponSearchVC!]
    }

    fileprivate func search(query: String) {
    //search request to API
    }

    func searchBarSearchButtonClicked(_ searchBar: UISearchBar) {
        guard let searchTerms = searchBar.text else {
            searchBar.endEditing(true)
            return
        }
        searchBar.endEditing(true)
        search(query: searchTerms)
    }

    func searchBarTextDidBeginEditing(_ searchBar: UISearchBar) {
        //if empty (no text) then display view with search categories
    }
}

这将导致如下视图：

我想在视图上显示这样的类别（类似于应用商店）：

一旦选择了类别，该类别视图就会消失，并显示我已经在商家和优惠券中使用的视图。