pushViewController not working properly - ios

Question

I've got a SidebarMenueController which is my entry point after starting the app.
Within there i've got a NavigationController embedded with a sidebar (slide out) menue. With sideBarDidSelectButtonAtIndex i catch which view, which should be loaded inside the NavigationController. When selecting an entry in the sidebar menue i want to push to another view.
Via printing (into the console) the selected menue entry, i can confirm that the selection is definitely working. But the pushViewController function is not loading the desired view.
I'm using no storyboard!
Any suggestions on how to fix this?
import UIKit
class SideBarMenueController: UIViewController, SideBarDelegate {
var sideBar:SideBar = SideBar()
lazy var menueButton: UIButton = {
let button = UIButton()
button.frame = CGRect(x: 0, y: 0, width: 30, height: 30)
button.backgroundColor = UIColor.clear
button.setImage(#imageLiteral(resourceName: "MenueIcon"), for: UIControlState.normal)
button.addTarget(self, action: #selector(didSelectMenueButton), for: UIControlEvents.touchUpInside)
return button
}()
override func viewDidLoad() {
super.viewDidLoad()
let layout = UICollectionViewFlowLayout()
let sideBarMenue = UINavigationController(rootViewController:FirstViewController(collectionViewLayout: layout))
self.addChildViewController(sideBarMenue)
sideBarMenue.view.frame = self.view.bounds
self.view.addSubview(sideBarMenue.view)
UINavigationBar.appearance().barTintColor = UIColor(red: 70/255, green: 174/255, blue: 253/255, alpha: 1)
let titleAttributes = [
NSFontAttributeName: UIFont.systemFont(ofSize: 20, weight: UIFontWeightBold),
NSForegroundColorAttributeName: UIColor.white
]
UINavigationBar.appearance().titleTextAttributes = titleAttributes
UINavigationBar.appearance().tintColor = UIColor.white
let NavigationMenueButton = UIBarButtonItem(customView: menueButton)
navigationItem.leftBarButtonItem = NavigationMenueButton
sideBar = SideBar(sourceView: self.view, menuItems: ["feed now", "feed times", "cats", "device status", "device setup", "about app"])
sideBar.delegate = self
}
func didSelectMenueButton() {
let layout = UICollectionViewFlowLayout()
let controller = FeedTimesController(collectionViewLayout: layout)
navigationController?.pushViewController(controller, animated: true)
}
func sideBarDidSelectButtonAtIndex(_ index: Int) {
if index == 0{
let controller = FirstViewController()
navigationController?.pushViewController(controller, animated: true)
print("touched index 0")
} else if index == 1{
let layout = UICollectionViewFlowLayout()
let controller = SecondViewController(collectionViewLayout: layout)
navigationController?.pushViewController(controller, animated: true)
print("touched index 1")
} else if index == 2{
let layout = UICollectionViewFlowLayout()
let controller = ThirdViewController(collectionViewLayout: layout)
navigationController?.pushViewController(controller, animated: true)
print("touched index 2")
} else if index == 3{
print("touched index 3")
} else if index == 4{
print("touched index 4")
} else if index == 5{
print("touched index 5")
}
sideBar.showSideBar(false)
}
}

Answer 1

It looks like you are creating a NavigationController with:
let sideBarMenue = UINavigationController(rootViewController:FirstViewController(collectionViewLayout: layout))
Then you are adding that controller's view as a subview to self.view:
self.view.addSubview(sideBarMenue.view)
But then later, in didSelect, you are trying to access (implied) self.navigationController:
navigationController?.pushViewController(controller, animated: true)
Not sure, but it looks like you want to access the nav controller via:
sideBar.navigationController
Without seeing the code / library you're using for SideBar, this may or may not resolve your issue.