Programmatically Pushing a ViewController

Question

I'm trying to push a ViewController programmatically.

Code:

var plus = UIButton()

plus.addTarget(self, action: #selector(plusPressed), for: .touchUpInside)

@objc func plusPressed() {
    print("plus")
    let createJournalVC = CreateJournalViewController()
    self.navigationController?.pushViewController(createJournalVC, animated: true)
}

What works:

1. Once the button is pressed, "plus" is printed to the console.

What doesn't work:

1. The ViewController is not pushed.

Details

• I am using a Navigation Controller & Tab Bar Controller.
• I am making this only programmatic, no storyboards.
• There is no error printed to the console, nothing actually happens.

Answer 1

If TabBarController comes after NavigationController then NavigationController can become nil. You should rather put TabBarController first and then put each ViewController (that are related to each tab) into there own NavigationController.

Storyboard:

Programmatically:

You need to create your TabBarController like this...

window = UIWindow(frame: UIScreen.main.bounds)
let tabCon = UITabBarController()
let navCon1 = UINavigationController(rootViewController: ViewController())
let navCon2 = UINavigationController(rootViewController: CreateJournalViewController())
let navCon3 = UINavigationController(rootViewController: AnotherViewController())
tabCon.viewControllers = [navCon1, navCon2, navCon3]
tabCon.tabBar.items?[0].title = NSLocalizedString("VC", comment: "comment")
tabCon.tabBar.items?[1].title = NSLocalizedString("CJV", comment: "comment")
tabCon.tabBar.items?[2].title = NSLocalizedString("AVC", comment: "comment")
window?.rootViewController = tabCon
window?.makeKeyAndVisible()