Bubble up events from child ViewControllers using the UIResponder chain

UIResponder+Events.swift

// LocationPickerViewController.swift

class LocationPickerViewController: UITableViewController {
    ...    
    override func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        didSelectLocation(locations[indexPath.row])
    }
}

extension UIResponder {
    @objc func didSelectLocation(_ location: Location) {
        next?.didSelectLocation(location)
    }
}

// AppFlowController.swift

class AppFlowController: UIViewController {
    // LocationPickerViewController is contained in childViewControllers hierarchy
    ...
    override func didSelectLocation(_ location: Location) {
        // handle event
    }
}

http://aplus.rs/2018/coordinator-missing-pattern-uikit/
https://github.com/radianttap/Coordinator

https://useyourloaf.com/blog/using-the-responder-chain/