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

Posted by Jeremy Taitelbaum
Jeremy Taitelbaum
4,680 Points

I am unclear as to what is being asked in the first part of the code challenge.

I guess I just don't fully understand what I am doing wrong in part one of this code challenge. I have tried this using the current syntax of Xcode 7 as well as the old syntax used in the previous video. I have tried using the func fetchTreehouseBlogPosts independent of a class called NetworkOperations, in which I assign an arbitrary URL to the queryURL, and change session and config to simple variables (eliminating the self. prefix from config in the assignment of the session variable). I have configured this to assume we are fetching a JSON file cast as a dictionary, and I have configured it to simple fetch raw NSData. In this case the completion handler simply takes NSData as a parameter. No matter what I try, I get the same "Bummer!: Make sure the method is called fetchTreehouseBlogPosts and that you are using correct syntax!" error, even though the preview button returns no errors (when I use the old syntax portrayed in the video). Can someone please explain what I am doing wrong?

Callbacks.swift 
import Foundation

// Add your code below
class NetworkOperations {

    lazy var config: NSURLSessionConfiguration = NSURLSessionConfiguration.defaultSessionConfiguration()
    lazy var session: NSURLSession = NSURLSession(configuration: self.config)
    let queryURL: NSURL

    typealias BlogPostCompletion = ([String: AnyObject]?) -> Void

    init(url: NSURL){
        self.queryURL = url
    }

    func fetchTreehouseBlogPosts (completion: BlogPostCompletion) {
        let request: NSURLRequest = NSURLRequest(URL: queryURL)
        let dataTask = session.dataTaskWithRequest(request) {
            (let data, let response, let error) in
            if let httpResponse = response as? NSHTTPURLResponse {
                switch(httpResponse.statusCode) {
                case 200:
                    let jsonDictionary = try!NSJSONSerialization.JSONObjectWithData(data!, options: []) as? [String: AnyObject]
                    completion(jsonDictionary)
                default:
                    print("GET request not successful. HTTP status code: \(httpResponse.statusCode)")
                }
            } else {
                print("Error: not a valid HTTP respone")
            }

        }

        dataTask.resume()

    }
}
Jeremy Taitelbaum
Jeremy Taitelbaum
4,680 Points

Never mind. I figured it out. I was overthinking it.