CODEWITHSUNDEEP
iosswift
Jason
Jason

Reputation: 1067

Bar button Item enabling problems in Swift

All,

In ViewDidLoad , I have set : 

BarButtonPAY.enabled = false

and that disables the bar button item and it is not selectable, thats fine.

I have an computed property on the View Controller, which enables the button with enable = true.

I am getting the error 'found nil in optional value' and I noticed that BarButtonItem is an optional. When I put the ? at the end of the variable it still does not enable. any ideas ? 

class ViewController: UIViewController {

    @IBOutlet weak var BarButtonPAY: UIBarButtonItem!

    var PayButton : Int {
        didSet {
                println("Barracuda")
                    BarButtonPAY?.enabled = true
        }
    }

I have set the computed property differently now in the view controller - like so (removed the var from init). 

@IBOutlet weak var BarButtonPAY: UIBarButtonItem!

    var PayButton : Int? {
        didSet {
            println("Barracuda")
            BarButtonPAY?.enabled = true
        }
    }


    required init(coder aDecoder: NSCoder) {
      //  self.PayButton = 0
        super.init(coder: aDecoder)
    }

    init() {
       // self.PayButton = 0
        super.init(nibName: nil, bundle: nil)

    }

When the button is pressed on the tableview cell. To select a product, and highlight the pay button as a BarButtonItem : 

@IBAction func SelectedButton(sender: UIButton) {


    // Set the colours and then highlight 'Next' on
    sender.backgroundColor = UIColor.blueColor()
    sender.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
    sender.setTitle("Ordered", forState: UIControlState.Normal)

    let test = ViewController()
    test.PayButton = 2

}

Upvotes: 2

Views: 762

Answers (2)

Zell B.
Zell B.

Reputation: 10286

Since PayButton is not an optional property I assume that you are setting its value in initializer before BarButtonPAY is initialized. Try setting a default value to PayButton 

var PayButton : Int = -1 {
    didSet {
            println("Barracuda")
                BarButtonPAY?.enabled = true
    }
}

or declare it as optional Int

var PayButton : Int? {
    didSet {
            println("Barracuda")
                BarButtonPAY?.enabled = true
    }
}

and remove the line when you set its value on init on both cases

Edited

Even after creating object typed ViewController in let test = ViewController() BarButtonPAY is not initialized (you can not use it until ViewController viewDidLoad method). A possible workaround : create another optional Integer property in ViewController and name it lets say initialValue. On selectedButton set initialValue as follow

@IBAction func SelectedButton(sender: UIButton) {


// Set the colours and then highlight 'Next' on
sender.backgroundColor = UIColor.blueColor()
sender.setTitleColor(UIColor.whiteColor(), forState: UIControlState.Normal)
sender.setTitle("Ordered", forState: UIControlState.Normal)

let test = ViewController()
test.initialValue = 2

}

then in ViewController viewDidLoad set PayButton to initialValue

override func viewDidLoad(){

    PayButton = initialValue
}

Upvotes: 1

Vasil Garov
Vasil Garov

Reputation: 4931

When you do this let test = ViewController() you are creating a new instance of your view controller. This way your outlets will be nil. Try accessing your view controller from storyboard:

let storyboard = UIStoryboard(name: "Main", bundle: nil)
let viewController = storyboard.instantiateViewControllerWithIdentifier("yourViewController") as! UIViewController
self.presentViewController(viewController, animated: true, completion: nil)

And then access the property:

viewController.PayButton = 2

Upvotes: 0

Related Questions