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iOS Build a Vending Machine App in Swift 2.0 Loading Data From a Resource Finishing Touches

Vending machine

protocol VendingMachineType { var selection: [VendingSelection] { get} var inventory: [VendingSelection: ItemType] { get } var amountDeposited: Double { get set } init (inventory: [VendingSelection: ItemType]) func vend(selection: VendingSelection, quantity: Double) throws

} protocol ItemType { var price: Double { get} var quantity: Double { get set } }

// Error Types

enum InventoryError: ErrorType { case InvalidResource case ConversionError case InvalidKey }

// Helper Classes

class PlistConverter { class func dictionaryFromFile(resource: String, ofType type: String) throws -> [String : AnyObject] { guard let path = NSBundle.mainBundle().pathForResource(resource, ofType: type) else {

        throw InventoryError.InvalidResource

    guard let dictionary = NSDictionary(contentsOfFile: path),
    let castDictionary = dictionary as? [String: AnyObject] else {
            throw InventoryError.ConversionError

   return castDictionary



class InventoryUnarchiver {

class func vendingInventoryFromDictionary(dictionary: [String : AnyObject]) throws-> [VendingSelection : ItemType] {

var inventory: [VendingSelection : ItemType] = [:]

    for (key, value) in dictionary {

        if let itemDict = value as? [String : Double],
        let price = itemDict["price"], let quantity = itemDict["quantity"] {
        let item = VendingItem(price: price, quantity: quantity)

            guard let key = VendingSelection( rawValue: key) else { throw InventoryError.InvalidKey

            inventory.updateValue(item, forKey: key)/ i don't know items is error 
        return inventory



// Concerte Types

enum VendingSelection : String { case Soda case DietSoda case Chips case Cookie case Sandwich case Wrap case CandyBar case PopTart case Water case FruitJuice case SportsDrink case Gum }

struct VendingItem { let price: Double var quantity: Double }

class VendingMachine: VendingMachineType {

let selection: [VendingSelection] = [.Soda,.DietSoda,.Chips,.Cookie
var inventory: [VendingSelection: ItemType]
var amountDeposited: Double = 10.0

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

func vend(selection: VendingSelection, quantity: Double) throws {
// add code

func deposit(amount: Double) {
// add code



inventory.updateValue(item, forKey: key) this is a problem. they said Argument type 'VendingItem' does not conform to expected type 'ItemType' how can i fix this problem please help me

1 Answer

Cindy Lea
Cindy Lea
Courses Plus Student 6,485 Points

You post all this code & dont tell us what the error is or what you need help with. We are all students & dont have time to look through bulky code without any clues. You can also attach c ode crrectly so its easier to read.