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iOS Build a Playlist Browser with Swift Refactoring Our Code Adding Multiple Playlists

Posted by Luke Annison
Luke Annison
7,724 Points

Getting error: "fatal error: unexpectedly found nil while unwrapping an Optional value"

Unfortunately on runtime the error above keeps appearing on various part of the application.

I managed to get rid of it once before but it is now showing up on the line:

artists += playlistDictionary["artists"] as! [String]

I'm wondering if anyone can shed some further light on what may be going on.

Thanks :)

Parker Skiba
Parker Skiba
5,583 Points

How do you have your artists array defined?

Robin Malhotra
Robin Malhotra
14,883 Points
Robin Malhotra
Robin Malhotra
14,883 Points

I means that the value of swift playlistDictionary["artists"] was nil on unwrapping. You may not have properly initialised the dict.

Jens Hagfeldt
Jens Hagfeldt
16,548 Points
Jens Hagfeldt
Jens Hagfeldt
16,548 Points

It worked fine for me when only replacing all instances of (as) with (as!) in MusicLibrary.swift... because it was there you got the warnings before the error, was it not?

1 Answer

Luke Annison
Luke Annison
7,724 Points
Luke Annison
Luke Annison
7,724 Points

Thanks for the answers everyone.

I'll have a look and report back when I get chance :)