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iOS Enumerations and Optionals in Swift Introduction to Optionals Nil Values in Collections

Joel Crouse
Joel Crouse
4,727 Points

Need help: Enums and Optionals in Swift code challenge

I'm kinda new to Swift so I'm probably making a really obvious mistake somewhere but I'm stuck and need help passing this code challenge. Thanks in advance!

optionals.swift
let movieDictionary = ["Spectre": ["cast": ["Daniel Craig", "Christoph Waltz", "Léa Seydoux", "Ralph Fiennes", "Monica Bellucci", "Naomie Harris"]]]

var leadActor: String = ""

// Enter code below
if let movie = movieDictionary["Spectre"], let cast = movie["cast"], let leadActor = cast[0] {

}

1 Answer

Heidi Puk Hermann
Heidi Puk Hermann
33,352 Points

Hi ,

you need to access each array/dictionary at a time, starting from the outside and going in. (Really hope this will make sense :) )

Imagine that you are building an app where people can store all their clothes. Each person has their own row, which contains a number of dictionaries - one for each type of clothes. The types of clothes are sorted by colour (just to have the same type of structure as you have...).

var clothesDictionary = [
   "person1": ["shirts": ["blue", "black"], "pants": ["black", "white"]], 
   "person2": ["shirts": ["pink", "red"], "pants": ["cowboy", "black"]]
]

/* Access the colour of the second pair of pants for person2... 
    - Since I don't know if I have a person2, I have to check if he exists first.
    - Then check if he has any pants, and then I can get out the colors.*/

if let person = clothesDictionary["person2"], let pants = person["pants"] {
   var secondPantsColor: String = pants[1]
}

Hope that it can help you :)

(Disclaimer: It is a copy of my exact same answer to a similar question yesterday :), If it does not make sense to you, just let me know, then I can elaborate in relation to the actual code-challenge \H )