Swift unexpectedly found nil while unwrapping an optional value

Question

I can't seem to unwrap this. My objects variable seems to be coming back nil.

//Creating a query
let query = PFUser.query()

query?.findObjectsInBackgroundWithBlock({ (objects : [PFObject]?, error : NSError?) -> Void in
     self.users.removeAll(keepCapacity : true)       
     for object in objects!
     {
         let user : PFUser = (object as? PFUser)!
         self.users.append(user.username!)
     }
     self.tableView.reloadData()
})

have you looked into the error object? The `error` and the optional type of the `object` are there for a reason: to tell you that something might go wrong and for you to able to look into and recover from it! — luk2302, Nov 08 '15 at 09:13
why? what does the `error` object tell you? Maybe it has something to do with the printed error `invalid session token`!? — luk2302, Nov 08 '15 at 09:16

score 1 · Accepted Answer · answered Nov 08 '15 at 09:28

1

The issue is with the objects : [PFObject]? argument, it is an optional; that means it can be nil. In your code you are trying to forcefully unwrap it for object in objects!. Due to some error you are getting nil objects array and you are trying to forcefully unwrap it, that's the reason for the crash.

You need to change the implementation like:

let query = PFUser.query()
query?.findObjectsInBackgroundWithBlock({ (objects : [PFObject]?, error : NSError?) -> Void in

  self.users.removeAll(keepCapacity : true)
  if let objects = objects
  {
        for object in objects
        {
           let user : PFUser = (object as? PFUser)!
            self.users.append(user.username!)
        }
   }
   self.tableView.reloadData()
})

answered Nov 08 '15 at 09:28

Midhun MP

103,496
31
153
200

With your help I fixed the bug. It let me to another bug. I keep getting `invalid token` errors. I'll try to find a solution to this problem. – Divine Davis Nov 08 '15 at 09:37
1

@DivineDavis: Thanks for your comment. I'm not familiar with parse and don't know why those session error is coming. May be this answer can help you to understand the issue : http://stackoverflow.com/questions/29423344/parse-invalid-session-token-code-209-version-1-7-1 Happy Coding !!! – Midhun MP Nov 08 '15 at 09:39

Swift unexpectedly found nil while unwrapping an optional value

1 Answers1