SplitViewController not work (Swift) - ios

Question

I'm trying to make an application that supports SplitViewController.
But my application crashes on startup.
How can I fix this?
MenuViewController --> ViewController --> DetailViewController
AppDelegate.swift
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
if UIDevice.current.userInterfaceIdiom == .pad {
self.window = UIWindow(frame: UIScreen.main.bounds)
self.window!.backgroundColor = UIColor.white
let splitViewController = UISplitViewController()
let menuViewController = MenuViewController()
let homeViewController = ViewController()
let secondViewController = DetailViewController()
let menuNavigationController = UINavigationController(rootViewController:menuViewController)
let homeNavigationController = UINavigationController(rootViewController:homeViewController)
let secondNavigationController = UINavigationController(rootViewController:secondViewController)
splitViewController.viewControllers = [menuNavigationController,homeNavigationController,secondNavigationController]
self.window!.rootViewController = splitViewController
self.window!.makeKeyAndVisible()
return true
} else {
}
return true
}
Error: (Example) - MenuViewController
override func viewDidLoad() {
super.viewDidLoad()
let isDarkMode = UserDefaults.standard.bool(forKey: "isDarkMode")
if isDarkMode == true {
self.tableView.backgroundColor = UIColor(red: 37/255, green: 38/255, blue: 39/255, alpha: 1)
} else {
self.tableView.backgroundColor = UIColor(red: 245/255, green: 245/255, blue: 245/255, alpha: 1)
}
tableView.tableFooterView = UIView(frame: CGRect.zero)
My StoryBoard:

Answer 1

Your problem is that you design your view controllers with storyboards, but you create them in code while effectively circumventing storyboards. That particular error happens because it was the responsibility of the storyboards to create the tableView, but now since you circumvented storyboards it is nil.
You have two options:
create the splitViewController in storyboards and use it as initial view controller of the app (and drop the programmatic creation of the splitViewController in appDelegate).
Get those view controllers from the storyboards, e.g.:
let menuViewController = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "menuController")
In this I assume that the storyboard name is "Main", and that you set the storyboard identifier of the MenuViewController is set to "menuController" - be careful, viewController's class (MenuViewController) is not the same thing as viewController's storyboard identifier (in my case I used '"menuController"'):
Do the same thing for all those view controllers that you created in storyboards.