HolidaysViewController.swift

import UIKit
import PKHUD

import RxSwift
import RxCocoa
import RxDataSources

class HolidaysViewController: UIViewController {
    
    // MARK: - Lifecycle Methods
    override func viewDidLoad() {
        super.viewDidLoad()
        
        setupUI()
        setupNavItem()
        
        bindTableView()
        bindNavItem()
        bindHUD()
        bindVisibilityState()
        
        viewModel.fetchHolidays{ (errorMessage) in
            self.showMessage(errorMessage)
        }
    }
    
    override func viewWillAppear(_ animated: Bool) {
        super.viewWillAppear(animated)
        setupNavBar()
    }
    
    // MARK: - Properties
    let disposeBag = DisposeBag()
    var viewModel: HolidaysViewModel!
    
    ....
    
}

// MARK: - Binding
extension HolidaysViewController {
    func bindTableView() {

        viewModel.holidays
            .bind(to: tableView.rx.items(cellIdentifier: "HolidayTableViewCell", cellType: HolidayTableViewCell.self)) { index, viewModel, cell in
                cell.viewModel = viewModel
            }
            .disposed(by: disposeBag)
        
        tableView.rx.modelSelected(HolidayViewModel.self)
            .bind(to: viewModel.selectedHoliday)
            .disposed(by: disposeBag)
        
        tableView.rx.itemSelected
            .subscribe(onNext: { (indexPath) in
                self.tableView.deselectRow(at: indexPath, animated: true)
            })
            .disposed(by: disposeBag)
    }
    
    func bindHUD() {
        
        viewModel.isLoading
            .subscribe(onNext: { [weak self] isLoading in
                isLoading ? self?.showProgress() : self?.hideProgress()
            })
            .disposed(by: disposeBag)
    }
    
    func bindNavItem() {
        chooseCountryItem.rx.tap
            .bind(to: viewModel.chooseCountry)
            .disposed(by: disposeBag)
        
        viewModel.selectedCountry
            .subscribe(onNext: { (country) in
                self.chooseCountryItem.title = country
            })
            .disposed(by: disposeBag)
    }
    
    func bindVisibilityState() {
        viewModel.selectedCountry
            .subscribe(onNext: { _ in
                self.tableView.isHidden = false
                self.chooseCountryLabel.isHidden = true
            })
            .disposed(by: disposeBag)
    }
    

}

// MARK: - UI Setup
extension HolidaysViewController {
    func setupUI() {
        overrideUserInterfaceStyle = .light
        self.view.backgroundColor = .white
        .....
    }
    
    func setupNavItem() {
        self.navigationItem.title = "Holidays"
        self.navigationItem.rightBarButtonItem = chooseCountryItem
    }
    
    func setupNavBar() {
        self.navigationController?
            .navigationBar
            .tintColor = .white
    }
}