Your job is to create a data task (not a download task), named dataTask, with a completion handler that returns the resu

Question

Spent way too much time on it and still can't get the correct solution, please help~ Thanks in advance!

Your job is to create a data task (not a download task), named dataTask, with a completion handler that returns the results of the data task. Add this data task between the commented section. Once that's done, within the body of the data task, return the results to the fetchTreehouseBlogPosts method's completion handler.

Callbacks.swift

import Foundation

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

func fetchTreehouseBlogPosts(completion: 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

  var dataTask: NSURLSessionDataTask
  let dataTask = session.dataTaskWithRequest(request){
    (let data, let response, let error) in
    completion(NSJSONSerialization.JSONObjectWithData(BlogPostComplication))
  }
  // Add code above

  dataTask.resume()
}

Answer 1 · 2015-08-17T12:27:12Z

August 17, 2015 12:27pm

Yupin,

I was able to get it working by changing the completion handler from this:

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

to this:

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

Also, just for future reference, when you are creating your data task, you have an extra variable with an assigned value of NSURLSessionDataTask. Since you are creating a data task and assigning it to a constant named dataTask, you do not need the line above it, which is var dataTask: NSURLSessionDataTask.

By having these two assignments, your var dataTask: NSURLSessionDataTask is unnecessary and unused. Also, the challenge tells you to assign to a constant, which means that you don't want to use any variables (var) anyway.

var dataTask: NSURLSessionDataTask
// The line above is unnecessary because you are assigning dataTask below. 

let dataTask = session.dataTaskWithRequest(request) {
    // Code for handling data task...
}

Hope this helps!!

Answer 2 · 2015-08-17T03:53:22Z

August 17, 2015 3:53am

Yupin,

When you are calling your completion handler, you have BlogPostCompletion misspelled; you currently have BlogPostComplication.

Change that to BlogPostCompletion and that should fix it.

Hope this helps!

Answer 3 · 2015-08-17T19:43:24Z

August 17, 2015 7:43pm

You bet! Thanks again Nick! I am very new to iOS, do you find learning Objective-C necessary for an new iOS developer or stick with one language. Thanks in advance!

Answer 4 · 2015-08-18T07:08:13Z

August 18, 2015 7:08am

Got chu! Thanks Nick for sharing your experience with me!! Best of the luck with your new app! Let me know when you app is published! I will sure check it out!!

Answer 5 · 2015-08-26T14:32:39Z

August 26, 2015 2:32pm

import Foundation

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

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

  dataTask.resume()
}

Why isnt my code working?

Whenever I hit submit the following message appears: Make sure you pass the correct order and type of parameters to the completion handler of the fetchTreehouseBlogPosts method.

Answer 6 · 2015-11-02T15:46:13Z

November 2, 2015 3:46pm

Bruna, use the following code:

import Foundation

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

// Change session.dataTaskWithURL to session.dataTaskWithRequest

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

  dataTask.resume()
}

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