Learning Swift – CS193p Spring 2021 Lecture 3

After lecture 3

So lecture 3 really pointed out to me where/why I had trouble learning Swift the first time around. The shortened closures and the whole “if this is the last argument for the function call, drop it” thing don’t make it easy for people new to the language. Words/phrases that came to mind when I realized what happened include “cute”, “nuanced”, and “too concise”. I wrote a whole post about it here. This lecture series will get me back on the right track to learn Swift. Link to after lecture 2/assignment post here.

Code

The code compiles. We did not hook the new model or viewmodel up to the view yet so no updates on the UI with this post. This is the first post where the code will be split across multiple files. (This means I should move to github or something similar.)

MemoryGame.swift

//
//  MemoryGame.swift
//  Memorize
//
//  Created by Austin on 5/28/21.
//  austinsnerdythings.com

import Foundation

struct MemoryGame<CardContent> {
    private(set) var cards: Array<Card>
    
    func choose(_ card: Card) {
        // this is where the game logic will go
    }
    
    init(numberOfPairsOfCards: Int, createCardContent: (Int) -> CardContent) {
        cards = Array<Card>()
        // add number of pairs of cards x 2 cards to card array
        for pairIndex in 0..<numberOfPairsOfCards {
            let content: CardContent = createCardContent(pairIndex)
            cards.append(Card(content: content))
            cards.append(Card(content: content))

        }
    }
    
    struct Card {
        var isFaceUp: Bool = false
        var isMatched: Bool = false
        var content: CardContent
    }
}

EmojiMemoryGame.swift

//
//  EmojiMemoryGame.swift
//  Memorize
//
//  Created by Austin on 5/28/21.
//  austinsnerdythings.com

import SwiftUI


class EmojiMemoryGame {
    static let emojis = ["?","?","?","?","?","?","?","?","?","?","?","?","?","✈️","?","?","?","?","?","?","?","?","?","?"]
    
    static func createMemoryGame() -> MemoryGame<String> {
        return MemoryGame<String>(numberOfPairsOfCards: 4) { pairIndex in
            EmojiMemoryGame.emojis[pairIndex]
        }
    }
    
private var model: MemoryGame<String> =
    MemoryGame<String>(numberOfPairsOfCards: 4) { _ in "A" }
    
    var cards: Array<MemoryGame<String>.Card> {
        return model.cards
    }
}

MemorizeApp.swift

//
//  MemorizeApp.swift
//  Memorize
//
//  Created by Austin on 5/25/21.
//  austinsnerdythings.com

import SwiftUI

@main
struct MemorizeApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

ContentView.swift is basically the same as last lecture. It wasn’t touched much (if at all) so I won’t include it. CS193p Spring 2021 lecture 3 was mostly about some Swift ideas and MVVM, not the view for the app.

Conclusion

I am super glad I started watching these lectures so they could get me going in the right direction for Swift. Sure I’m a bit frustrated now because I realize where I went wrong, but I’m excited to get back to lecture 4 and the assignment after this long weekend.