Swift: Failing to set a [String] through a segue using the sender

Question

Good day. I'm creating my first own app and have ran into an issue. I have a AR scene with clickable stuff which when you touch them a segue triggers into a ViewController and sets that view controllers labels and textview depending on what was touch on screen.

Explanations: 1. CaseViewController is the target view controller. 2. the "artNews" and "politicalNews" are string arrays in which I've written 3 strings, they are defined and are never nil.

Question: I get a crash due to the segueInputText being nil. Why does it become nil and how do I correct it?

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {

    let destinationVC = segue.destination as! CaseViewController
    destinationVC.segueInputText = sender as? [String]

    print("\(String(describing: sender))")
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {

    guard let touchLocation = touches.first?.location(in: sceneView),
        let hitNode = sceneView?.hitTest(touchLocation, options: nil).first?.node,
        let nodeName = hitNode.name
        else { return }

    if nodeName == imageNameArray[0] {

        performSegue(withIdentifier: "CaseViewController", sender: artNews)

    } else {
        print("Found no node connected to \(nodeName)")
        return
    }

    if nodeName == imageNameArray[1] {

        performSegue(withIdentifier: "CaseViewController", sender: politicalNews)

    } else {
        print("Found no node connected to \(nodeName)")
        return
    }

the CaseViewController has UILabels and UITextViews connected and this:

    var segueInputText : [String]? {
    didSet {
        setupText()
    }
}

    func setupText() {

    // Why are these values nil? 
    testLabel.text = segueInputText![0]
    ingressLabel.text = segueInputText![1]
    breadLabel.text = segueInputText![2]

    testLabel.reloadInputViews()
    ingressLabel.reloadInputViews()
    breadLabel.reloadInputViews() //breadLabel is a UITextView
}

Thank you for reading my question! Kind regards.

Answer 1

Don't use the didSet observer in this case. It will never work.

In setupText() IBOutlets are accessed which are not connected yet at the moment prepare(for is called.

---

Remove the observer

var segueInputText : [String]?

and call setupText in viewWillAppear

override func viewWillAppear(_ animated: Bool) {
    super.viewWillAppear(animated)
    setupText()
}