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

Samuel Sohn
Samuel Sohn
4,770 Points
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
Ben Griffith
Ben Griffith
5,808 Points

Your dataObject should be of type NSData, not NSDictionary.

Samuel Sohn
Samuel Sohn
4,770 Points
Samuel Sohn
Samuel Sohn
4,770 Points

Thank you! This fixed the issue.