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iOS Build a Weather App with Swift (Retired) Concurrency Writing Concurrent Networking Code

Posted by Aby Mathew
Aby Mathew
Courses Plus Student 2,432 Points

Extra argument 'completionHandler' in call, What is the error?

let sharedSession = NSURLSession.sharedSession() let downloadTask: NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(forecastURL, completionHandler: { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void! in println(response) }) downloadTask.resume()

1 Answer

Aby Mathew
Aby Mathew
Courses Plus Student 2,432 Points

The code have to be changed as follows:

let sharedSession = NSURLSession.sharedSession()
        let downloadTask: NSURLSessionDownloadTask = sharedSession.downloadTaskWithURL(forecastURL!, completionHandler:
            { (location: NSURL!, response: NSURLResponse!, error: NSError!) -> Void in
            println(response)
        })
        downloadTask.resume()

forecastURL to forecastURL!