Swift - error when calling random value in array

Question

I'm trying to call a random value within my array into my query where it says "objectId" but I'm getting an error "EXC_BAD_INSTRUCTION" where it says let votes = voteCount1["votes"] as Int. It is below my IBAction with the function addVote1.

Where am I going wrong? I'm trying to retrieve the values for each variable that are all within a certain row in my Parse data controller (each one with a certain objectId) and send a vote to the corresponding variable within that row but I'm getting an error. The only way for me not to get the error is if I specifically define the objectId in place of where it says "objectId" in query.getObjectInBackgroundWithId("objectId"). Where could I be going wrong?

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    var voteCount1 = PFObject(className: "VoteCount")
    voteCount1["choices"] = 2
    voteCount1["votes"] = Int()
    voteCount1["votes2"] = Int()
    voteCount1["optionName"] = String()
    voteCount1["optionName2"] = String()

    var voteCount2 = PFObject(className: "VoteCount2")
    voteCount2["choices"] = 3
    voteCount2["votes"] = Int()
    voteCount2["votes2"] = Int()
    voteCount2["votes3"] = Int()
    voteCount2["optionName"] = String()
    voteCount2["optionName2"] = String()
    voteCount2["optionName3"] = String()

    var voteCount3 = PFObject(className: "VoteCount3")
    voteCount3["choices"] = 4
    voteCount3["votes"] = Int()
    voteCount3["votes2"] = Int()
    voteCount3["votes3"] = Int()
    voteCount3["votes4"] = Int()
    voteCount3["optionName"] = String()
    voteCount3["optionName2"] = String()
    voteCount3["optionName3"] = String()
    voteCount3["optionName4"] = String()

    let array = ["BiEM17uUYT", "TtKGatVCi9"]
    let randomIndex = Int(arc4random_uniform(UInt32(array.count)))
    let objectId = array[randomIndex]




}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

@IBOutlet weak var pollResults1: UILabel!

@IBAction func addVote1(sender: AnyObject) {
    var query = PFQuery(className: "VoteCount")
    query.getObjectInBackgroundWithId("objectId") {
        (voteCount1: PFObject!, error: NSError!) -> Void in
        if error != nil {
            NSLog("%@", error)
        } else {
            voteCount1.incrementKey("votes")
            voteCount1.saveInBackgroundWithTarget(nil, selector: nil)
        }
        let votes = voteCount1["votes"] as Int
        let votes2 = voteCount1["votes2"] as Int
        self.pollResults1.text = "\(votes)"
        }
    }
}

Answer 1

I see that in viewDidLoad you define some objects, store them in local variables, and their values are lost as the method ends. So they do not contribute in any way to the query and the data that's supposed to be in the parse db.

That said, I expect that the call to getObjectInBackgroundWithId returns no match, and that the voteCount1 closure parameter is nil.

If that happens, you should see an error message printed to the console.

So, the exception happens because you are accessing the voteCount1 variable, which contains nil. You should move that code in the else branch:

    if error != nil {
        NSLog("%@", error)
    } else {
        voteCount1.incrementKey("votes")
        voteCount1.saveInBackgroundWithTarget(nil, selector: nil)

        let votes = voteCount1["votes"] as Int
        let votes2 = voteCount1["votes2"] as Int
        self.pollResults1.text = "\(votes)"
    }

but I think there's some other mistake in your code logic, basing on the consideration I made at beginning of this answer.