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iOS Build a Weather App with Swift (Retired) Pulling Data From the Web Making a Network Call

Pierre Smith
Pierre Smith
11,842 Points
Posted by Pierre Smith
Pierre Smith
11,842 Points

I keep getting value of optional type 'nsurl?' not unwrapped when NSData dataWithContentsOfURL:option:error: is used

import UIKit

class ViewController: UIViewController {

private let apiKey = "d0454418a440c7bac837ee42b7e80e0a" let location = "43.854359,-79.085962" let location2 = "37.8267,-122.423"

override func viewDidLoad() { super.viewDidLoad() // Do any additional setup after loading the view, typically from a nib.

let baseURL = NSURL(string: "https://api.forecast.io/forecast/\(apiKey)/")
let forecastURL = NSURL(string: "37.8267,-122.423", relativeToURL: baseURL)

let weatherData = NSData.dataWithContentsOfURL(forecastURL, options: nil, error: nil)

println(weatherData)

}

2 Answers

Joseph Bauman
Joseph Bauman
3,063 Points

From a different thread. There are at least two problems one is that the forecastURL is an optional (that goes to nil)that need to be unwrapped and dataWithContentsOfURL is no longer working in the current Xcode. ''' class ViewController: UIViewController {

private let apiKey = ""
private let locationPoints = "40.524757, -74.471325"

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    let baseURL = NSURL(string:"https://api.forecast.io/forecast/\(apiKey)/")

    let encodedPoints = locationPoints.stringByAddingPercentEscapesUsingEncoding(NSUTF8StringEncoding)! // This method returns an optional, we need to force unwrap

    let forecastURL = NSURL(string: encodedPoints, relativeToURL: baseURL)

    let weatherData = NSData(contentsOfURL: forecastURL!, options: nil, error: nil)


    println(weatherData)

}

'''

Pierre Smith
Pierre Smith
11,842 Points
Pierre Smith
Pierre Smith
11,842 Points

This is a long shot but do you know why it was removed?

Bernard Paulet
Bernard Paulet
3,364 Points
Bernard Paulet
Bernard Paulet
3,364 Points

Thanks a lot! I had the same problem, could not solve it without your post!

Andres Oliva
Andres Oliva
7,810 Points
Andres Oliva
Andres Oliva
7,810 Points

Try adding a ! sign after forecastURL in the line of weatherData.

Like this:

let weatherData = NSData.dataWithContentsOfURL(forecastURL!, options: nil, error: nil)