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iOS Build a Weather App with Swift Interacting with Data From the Web Writing Concurrent Networking Code

Schott Taylor
PLUS
Schott Taylor
Courses Plus Student 7,125 Points
Posted by Schott Taylor
Schott Taylor
Courses Plus Student 7,125 Points

Force Unwrap? Or Normal Optionals? - Swift: Writing Concurrent Networking Code

So I've encountered a problem following the Swift course "Build a Weather App" and in one point in the video I'm trying to get data from the web, and he force unwraps all his optionals like this:

let dataTask = session.dataTaskWithRequest(request) { (data: NSData!, response: NSURLResponse!, error: NSError!) -> Void in print(data!) print("I'm on the backround thread") }

But this gives me and error while his code is error free. I changed my optionals to be normal with a "?" instead of a "!" and the error disappeared but i still didn't retrieve my data. Is there something obvious I'm missing or is there something i don't know?

jcorum
jcorum
71,830 Points

Can you tell us what the error is that you are getting?

Schott Taylor
Schott Taylor
Courses Plus Student 7,125 Points
Schott Taylor
Schott Taylor
Courses Plus Student 7,125 Points

The error is: "Cannot convert value of type '(NSData!,NSURLResponse!,NSError!) -> Void'to expected argument type '(NSData?, NSURLReponse?,NSError?) -> Void'