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iOS Build a Weather App with Swift (Retired) Pulling Data From the Web Fetching JSON Data

Posted by sv
sv
1,244 Points

Having trouble getting past this

My answer is correct I think:

let courseData = NSDATA(string: courseURL!, options: nil , error: nil)

But tree house giving me an error to set courseData = NSDATA output

students_code.swift 
import Foundation
let treehouseBaseURL = NSURL(string: "https://api.teamtreehouse.com/")
let courseURL = NSURL(string: "/course/\(courseID)", relativeToURL: treehouseBaseURL)
let courseData  = NSDATA(string: courseURL!, options: nil , error: nil)

3 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

looking at the NSData class reference, we can see that it has a method that looks like this:

init?(contentsOfURL aURL: NSURL,
            options mask: NSDataReadingOptions,
              error errorPtr: NSErrorPointer)

its an init method which means you call it like so:

NSData(contentsOfURL: aURL,
            options: someOptions,
              error: someError)

you wrote NSData in all caps. it needs to be NSData not NSDATA. also the first parameter is named contentsOfURL, not string.

import Foundation
let treehouseBaseURL = NSURL(string: "https://api.teamtreehouse.com/")
let courseURL = NSURL(string: "/course/\(courseID)", relativeToURL: treehouseBaseURL)
let courseData  = NSData(contentsOfURL: courseURL!, options: nil , error: nil)
sv
sv
1,244 Points
sv
sv
1,244 Points

Thanks for the very quick response. Unfortunately I am still getting an error: Bummer! You need to assign the result of the NSData call to the courseData constant.

Here is my code:

import Foundation let treehouseBaseURL = NSURL(string: "https://api.teamtreehouse.com/") let courseURL = NSURL(string: "/course/(courseID)", relativeToURL: treehouseBaseURL) let courseData = NSData(string: courseURL!, options: nil , error: nil)

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

also the first parameter is named contentsOfURL, not string.

you need to change the parameter name to contentsOfURL

let courseData  = NSData(contentsOfURL: courseURL!, options: nil , error: nil)
sv
sv
1,244 Points
sv
sv
1,244 Points

That did it - much thanks!

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

no problem glad I could help!