Attempting to check if PFFile has data or not

Question

I am attempting to check if a PFFile has data before it attempts to pull the image from the background. I am attempting this because I keep getting a fatal crash if you try and open one of the objects and there is no image! My problem is that I can't get the data check to work. PFFile != nil does not work and you can't check if it exists with if (recipeImageData) because PFFile does not conform to the boolean protocol. Any help would be appreciated!

Here is the declaration of the variable:

var recipeImageData: PFFile = PFFile()

And here is the function for fetching the data:

override func viewWillAppear(animated: Bool) {
  navItem.title = recipeObject["Name"] as? String
  recipeImageData = recipeObject["Image"] as PFFile //Fatally crashes on this line
  // Fetch the image from the background
  if (recipeImageData) {
    recipeImageData.getDataInBackgroundWithBlock({
      (imageData: NSData!, error: NSError!) -> Void in
      if error == nil {
        self.recipeImage.image = UIImage(data: imageData)?
      } else {
        println("Error: \(error.description)")
      }
    })
  }
}

EDIT:

I just tried this seeing that I probably am making a check in the wrong area. Here is my updated code.

override func viewWillAppear(animated: Bool) {
  navItem.title = recipeObject["Name"] as? String
  if let recipeImageData = recipeObject["Image"] as? PFFile {
    // Fetch the image in the background
    recipeImageData.getDataInBackgroundWithBlock({
      (imageData: NSData!, error: NSError!) -> Void in
      if error == nil {
        self.recipeImage.image = UIImage(data: imageData)?
      } else {
        println("Error: \(error.description)")
      }
    })
  }
}

have you tried? `if(recipeObject["Image"])` before `recipeImageData = recipeObject["Image"]` — Klevison, Mar 24 '15 at 14:04
This results in a fatal crash with Parse though saying there is an unrecognized selector being sent to the class in parse though — Olyve, Mar 24 '15 at 14:05
Yeah I realized that @Klevison and the updated code shows the check where I attempt to check for it but I think my updated code might still be wrong. PFFile can't be an optional so that might be wrong — Olyve, Mar 24 '15 at 14:06
@KlevisonMatias I tired the check you suggested too but I get the same fatal error with Parse not recognizing a selector sent to it — Olyve, Mar 24 '15 at 14:12

score 6 · Accepted Answer · answered Mar 24 '15 at 14:42

This check actually works just fine, there was another issue that was causing the crash. The correct code is posted below:

override func viewWillAppear(animated: Bool) {
  navItem.title = recipeObject["Name"] as? String
  if let recipeImageData = recipeObject["Image"] as? PFFile {
    // Fetch the image in the background
    recipeImageData.getDataInBackgroundWithBlock({
      (imageData: NSData!, error: NSError!) -> Void in
      if error == nil {
        self.recipeImage.image = UIImage(data: imageData)?
      } else {
        println("Error: \(error.description)")
      }
    })
  }
}

Attempting to check if PFFile has data or not

1 Answers1