TableView UserDefaults 'unexpectedly found nil while unwrapping an Optional value'

Question

anska OP

Created Nov ’15

Replies 8

Boosts 0

Views 3.1k

Participants 3

Hello there!

I am currently facing a relatively big problem of mine, and I can't seem to figure it out. You see, I am currently displaying data from my user defaults in my table view, and when I click one of these items - I get an error like this:

fatal error: unexpectedly found nil while unwrapping an Optional value

This is the code I am using;

  override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "selected" {
            let VC5 : ViewControllerFive = segue.destinationViewController as! ViewControllerFive
            let indexPath = self.tableView.indexPathForSelectedRow
         
            if let nText = self.myDefs.objectForKey("Name")?.objectAtIndex(indexPath!.row) as? String{
                VC5.tText = "Your name:  " + nText
            }
            self.tableView.deselectRowAtIndexPath(indexPath!, animated: true)
        }

This seemed to work for about a week ago, until I decided to re-design my user interface completely. If it's relevant, I can also post the other code related to my table view:

func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        if let defs = myDefs.objectForKey("Name") {
            return defs.count
        } else {
            return 0
        }
    }
  
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        let cell = self.tableView.dequeueReusableCellWithIdentifier("cell", forIndexPath: indexPath) as! TableViewCell
      
        if let label = cell.prevText{
            label.text = self.myDefs.valueForKey("Name")?.objectAtIndex(indexPath.row) as? String
        }
    }
        return cell
      
    }

Help would be greatly appreciated!

Boost

Answer 1

junkpile OP

Nov ’15

You should use objectForKey, not valueForKey.

On what line of code is the error occurring?

0

Answer 2

anska OP

Nov ’15

if let hText = self.myDefs.objectForKey("Name")?.objectAtIndex(indexPath!.row) as? String{
                VC5.tText = "Your name: " + nText <-- This line gives me an error about this optional value..
            }

0

Answer 3

junkpile OP

Nov ’15

That seems odd. VC5 can't be nil or it would have crashed a few lines up when you initially tried to force downcast the destinationViewController, and nText can't be nil because it's in an if let. I suspect it's actually the previous line and it's indexPath that's nil. Are you deselecting the row in didSelectRowAtIndexPath?

0

Answer 4

DressTheMonkey OP

Nov ’15

I would set a breakpoint on that line and examine some stuff. My guess would be that tText could be nil.

0

Answer 5

anska OP

Nov ’15

Yes, I do also find this strange. I got this error after removing/re-adding components to my view controllers because I was updating the user interface. However, I am quite sure that's not the case either. It prints the correct text selected that I want to be displayed at the ViewController5, but I get this error about unwrapping optional value..

Somehow the error gets shown on the line above:

if let hText = self.myDefs.objectForKey("LagretDatoer")?.objectAtIndex(indexPath!.row) as? String{

And yes, I also tried objectForKey as you can see.

0

Answer 6

anska OP

Nov ’15

I could maybe do an if/else to see if the error stil persists. Will update.

0

Answer 7

anska OP

Nov ’15

I have now tried to play around with the indexPath, and it looks like it is something strange happening with it. When I removed all the code in the "prepareForSegue", and just ran this code on the selection:

It worked, but nothing showed up - as expected. However, when I tried to just print "indexPath!.row", in the prepareForSegue - I got an error. What would you suggest me to do, to get this working? here is the code for both:

func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
       self.performSegueWithIdentifier("selected", sender: self)
    }
   
    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
        if segue.identifier == "selected" {
            let VC5 : ViewControllerFive = segue.destinationViewController as! ViewControllerFive
            let indexPath = self.tableView.indexPathForSelectedRow
           
            print(indexPath!.row)
        }

printing the indexPath in the tableView didSelectRowAtIndexPath seems to work, but not the prepareForSegue. Any ideas?

0

Answer 8

junkpile OP

Nov ’15

Perhaps your segue is being triggered before didSelectRowAtIndexPath is called. Myself I prefer to define the segue from VC to VC, as opposed to from a button or table cell, and programmatically initiate it (performSegueWithIdentifier) from didSelectRowAtIndexPath, passing the NSIndexPath as the sender (or better yet, the data model object corresponding to the index path).

0