Grabbing object from user in parse - swift

Question

In a collection view I have an array of events and each cell has a background image view of the event image which is saved as a PFFile. That works fine and good until I added this code. The user has a property "profilePicture" which I want to display in the cell as well. Here is my code which is inside of the block which gets the event image.
let eventCreator : PFUser = event?.objectForKey("user") as! PFUser
let creatorImage : PFFile = eventCreator.objectForKey("profilePicture") as! PFFile
creatorImage.getDataInBackgroundWithBlock({ (data, error) -> Void in
cell.creatorImageView.image = UIImage(data: data!)
})
Here is the full method which gets the event and all it's properties (like which I said, worked perfectly fine before I added the above code. Now it throws an "fatal error: unexpectedly found nil while unwrapping an Optional value" error. Any help?
func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
//sets up cell
let cell : EventCell = collectionView.dequeueReusableCellWithReuseIdentifier("cell", forIndexPath: indexPath) as! EventCell
//adds attend action
cell.attendButton.addTarget(self, action: "buttonTapped:", forControlEvents: UIControlEvents.TouchUpInside)
//queries parse for events
let event = events?[indexPath.row]
event?.eventImage.getDataInBackgroundWithBlock({ (data, error) -> Void in
if let data = data, image = UIImage(data: data) {
if cell.isFlipped == false {
cell.eventBackgroundImage.image = image
cell.eventTitleLabel.text = event?.eventTitle
//gets profile picture of events creator
let eventCreator : PFUser = event?.objectForKey("user") as! PFUser
let creatorImage : PFFile = eventCreator.objectForKey("profilePicture") as! PFFile
creatorImage.getDataInBackgroundWithBlock({ (data, error) -> Void in
cell.creatorImageView.image = UIImage(data: data!)
})
//sets correct category for cell image
if event?.category == "" {
cell.categoryImageView.image = nil
}
if event?.category == "The Arts" {
cell.categoryImageView.image = UIImage(named: "University")
}
if event?.category == "The Outdoors" {
cell.categoryImageView.image = UIImage(named: "Landscape")
}
//TODO finish categories
}
else if cell.isFlipped == true {
cell.eventDescriptionLabel.text = event?.eventDescription
}
}
})

Answer 1

Forcefully casting a nil-valued optional variable to a non-optional one will lead to a runtime error. Why are you using as! operator ? You should probably use the as? operator instead and check for any nil values to make sure the cast was successful before doing anything.
[Edit]
Try something like this:
if let eventCreator = event?.objectForKey("user") as? PFUser {
if let creatorImage = eventCreator.objectForKey("profilePicture") as? PFFile {
creatorImage.getDataInBackgroundWithBlock({ (data, error) -> Void in
cell.creatorImageView.image = UIImage(data: data!)
})
}
}