UIPickerView items from segue are not loaded

Question

I am trying to load items into UIPickerView, these items are loaded from a list that is populated in a prepareforsegue function in a previous view

class AddItemViewController: UIViewController, UIPickerViewDataSource, UIPickerViewDelegate {


    @IBOutlet weak var ItemPickView: UIPickerView!
    @IBOutlet weak var textboxName: UITextField!

    var options: [String]?
    var name: String?

    override func viewDidLoad() {
        super.viewDidLoad()
        print("viewdidload started")
        ItemPickView.delegate = self
        ItemPickView.dataSource = self
        textboxName.inputView = ItemPickView
        print("viewdidload ended")
        print(options)
    }

    func numberOfComponentsInPickerView(pickerView: UIPickerView) -> Int {
        return 1
    }

    func pickerView(pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
        options!.count
    }

    func pickerView(pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
        return options![row]
    }

    func pickerView(pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
        textboxName.text = options![row]
    }
}

My segue code

 override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {

    if segue.identifier == "AddNewItem" {
        print("segue started")
        let controller = segue.destinationViewController as? AddItemViewController
        controller?.options = ["test1","test2","test3"]
        print("segue ended")
    }
 }

It seems that the UIPickerView is initiated before the list is changed. Any workaround for this?

Thanks a lot

Edit: here is the log from print statments

segue started
segue ended
viewdidload started
viewdidload ended
nil
fatal error: unexpectedly found nil while unwrapping an Optional value
(lldb)

It seems segue finishes before viewdidload.. then why isn't options list updated?

code is correct. did you debug ? is the code going in the if condition of prepareForSegue — Shubhank
yes the code is running correctly, print statements do print... but the viewDidLoad seems to run before the segue code.. also viewDidAppear did not help — Anya Alstreim
your code do not have print statements. please update your code with them and then show the log output sequence — Shubhank

V Laghane V Laghane · Accepted Answer · 2016-07-07T16:43:57

One way is to tag the fileowner as the datasource and delegate[ in the XIB ]. This way there is no need to wait did View didload to attach the necessary data source and delegate.

UIPickerView items from segue are not loaded

1 Answers