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iOS Build a Weather App with Swift Managing Complexity Callback Methods With Closures

Enrique Munguía
Enrique Munguía
14,311 Points
Posted by Enrique Munguía
Enrique Munguía
14,311 Points

Error in code challenge

In step 2/2 I'm getting an error, I tried to put the code in xcode and it works, if anyone can spot my error would be nice. The code I added is between comments. Thank you.

Callbacks.swift 
import Foundation

// Add your code below
typealias BlogPostCompletion = ((NSData!, NSURLResponse!, NSError!) -> Void)

func fetchTreehouseBlogPosts(handler: BlogPostCompletion) {
  let blogURL = NSURL(string: "http://blog.teamtreehouse.com/api/")
  let requestURL = NSURL(string: "get_recent_summary/?count=20", relativeToURL: blogURL)

  let request = NSURLRequest(URL: requestURL!)

  let config = NSURLSessionConfiguration.defaultSessionConfiguration()
  let session = NSURLSession(configuration: config)

    // Add your code between the comments
    let dataTask = session.dataTaskWithRequest(request,
        completionHandler: { (data: NSData!, response: NSURLResponse!, error: NSError!) -> Void in

        handler(data, response, error)

    })
  // Add code above

  dataTask.resume()
}

1 Answer

Dominic Pettifer
Dominic Pettifer
4,338 Points

I think your example is correct, but I think this code challenge is a bit buggy, so try the following between the comments...

let dataTask = session.dataTaskWithRequest(request) {
    (let data, let response, let error) in

    completion(data, response, error)
}

I couldn't even get this to work initially until I copied the entire code file, refreshed the page and copied it back into Step 2 with no changes, and it worked.

Enrique Munguía
Enrique Munguía
14,311 Points
Enrique Munguía
Enrique Munguía
14,311 Points

Yeah I tried what you suggested and it worked, thank you.

Corey Dutson
Corey Dutson
Courses Plus Student 3,193 Points
Corey Dutson
Corey Dutson
Courses Plus Student 3,193 Points

Ugh. Thanks for this. I was bashing my head against a wall trying to figure out what the hell was going on. FYI the code I was using (that didn't work) was:

let dataTask = session.dataTaskWithRequest(request) {
    (let data, let response, let error) in
        completion(data, response, error)
}

Basically the same, but with slight indentation differences. I'd chalk this one up to the code checker spazzing out.