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iOS Build a Vending Machine App in Swift Modeling An Interface Concrete Types and Property Lists

Lana Wong
Lana Wong
3,968 Points

I'm copying the code, but still not working

I'm copying the code Pasan did in this video, and I can't find out what is wrong with my code in Xcode.

import Foundation

enum VendingSelection {
    enum VendingSelection {
        case soda
        case dietSoda
        case chips
        case cookie
        case sandwich
        case wrap
        case candyBar
        case popTart
        case water
        case fruitJuice
        case sportsDrink
        case gum
    }
}

protocol VendingItem {
    var price: Double {get }
    var quantity: Int {get set}
}

protocol VendingMachine {
    var selection: [VendingSelection] { get }
    var inventory: [VendingSelection: VendingItem] { get set }
    var amountDeposited: Double { get set }

    init(inventory: [VendingSelection: VendingSelection])
    func vend(_ quantity: Int,_ selection: VendingSelection) throws
    func deposite(_ amount: Double)
   }

struct Item: VendingItem{
    let price: Double
    var quantity: Int

}


class FoodVendingMachine: VendingMachine {
    let selection: [VendingSelection] = [.soda, .dietSoda, .chips, .cookies, .wrap, .sandwich, .candyBar, .poptart, .water, .fruitJuice, .sportsDrink, .gum]
    var inventory: [VendingSelection: VendingItem]
    var amountDeposited: Double = 10.0

        required init(inventory: [VendingSelection : VendingSelection]) {
            self.inventory = inventory
        }
        func vend(_ quantity: Int, selection: VendingSelection) throws {
        }
        func deposit( _ amount: Double) {
        }
}

2 Answers

Hi Lana,

I assume it is because you have created an enum from within another enum 'Vending Selection'.

Try:

    enum VendingSelection {
        case soda
        case dietSoda
        case chips
        case cookie
        case sandwich
        case wrap
        case candyBar
        case popTart
        case water
        case fruitJuice
        case sportsDrink
        case gum
    }

I hope this works,

All the best,

Mitch

Lana Wong
Lana Wong
3,968 Points

Ok, I fixed it and a few other problems, but I still get errors. Can you please help me solve them. I really appreciate it! :)

import Foundation

    enum VendingSelection {
        case soda
        case dietSoda
        case chips
        case cookie
        case sandwich
        case wrap
        case candyBar
        case popTart
        case water
        case fruitJuice
        case sportsDrink
        case gum
    }


protocol VendingItem {
    var price: Double {get }
    var quantity: Int {get set}
}

protocol VendingMachine {
    var selection: [VendingSelection] { get }
    var inventory: [VendingSelection: VendingItem] { get set }
    var amountDeposited: Double { get set }

    init(inventory: [VendingSelection: VendingSelection])
    func vend(_ quantity: Int,_ selection: VendingSelection) throws
    func deposite(_ amount: Double)
   }

struct Item: VendingItem{
    let price: Double
    var quantity: Int

}


class FoodVendingMachine: VendingMachine {
    let selection: [VendingSelection] = [.soda, .dietSoda, .chips, .cookie, .wrap, .sandwich, .candyBar, .popTart, .water, .fruitJuice, .sportsDrink, .gum]
    var inventory: [VendingSelection: VendingItem]
    var amountDeposited: Double = 10.0

        required init(inventory: [VendingSelection : VendingSelection]) {
            self.inventory = inventory 
        }

        func vend(_ quantity: Int, _ selection: VendingSelection) throws {
        }

    func deposit( _ amount: Double) {
        }
}
Adam O' Ceallaigh
Adam O' Ceallaigh
2,962 Points

Hi Lana I doubt you haven't figured it out by now but in the above example the method inside the protocol Vending Machine says deposite and the function call in the class FoodVendingMachine says deposit and it won't conform to the protocol because of this because you don't have all the methods properly adhered to.