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iOS Build a Weather App with Swift (Retired) Concurrency Using Our JSON Data

Posted by Samuel Sohn
Samuel Sohn
4,770 Points

NSDictionary is not convertible to NSData error 

let dataObject = NSDictionary(contentsOfURL: location)

let weatherDictionary: NSDictionary = NSJSONSerialization.JSONObjectWithData(dataObject, options: nil, error: nil) as
                NSDictionary

I was originally receiving the error "Expression does not conform to type '$T4' following the code in the video. After changing the code to escape the dataObject, seen below

let dataObject = NSDictionary(contentsOfURL: location)
let weatherDictionary: NSDictionary =
                NSJSONSerialization.JSONObjectWithData(dataObject!, options: nil, error: nil) as
                NSDictionary

I now receive the error NSDictionary is not convertible to NSData error. Any idea as to what is causing this?

1 Answer

Ben Griffith
Ben Griffith
5,808 Points

Your dataObject should be of type NSData, not NSDictionary.

Samuel Sohn
Samuel Sohn
4,770 Points

Thank you! This fixed the issue.