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

Aananya Vyas
Aananya Vyas
20,157 Points

i can not understand why 'selection' isn't recognised and the error isn't going away. please help.

//  VendingMachine.swift
//  VendingMachine
//  Created by Aananya on 05/03/17.
//  Copyright © 2017 Treehouse Island, Inc. All rights reserved.

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 : VendingItem])
    func vend(_ quantity : Int , _ selection : VendingSelection) throws
    func deposit(_amount:Double)

struct Item {
    let price : Double
    var quantity : Int
enum InventoryError : Error {
case invalidResourse
case conversionFailure
case invalidSelection
class PlistConverter {
    static func dictionary (fromFile name : String , ofType type : String) throws -> [String : AnyObject]{
        guard let path = Bundle.main.path(forResource: name, ofType: type) else {
        throw InventoryError.invalidResourse
        guard let dictionary = NSDictionary(contentsOfFile : path) as? [String:AnyObject]  else {
        throw InventoryError.conversionFailure

    return dictionary

    class InventoryUnarchiver {
        static func vendingInventory (fromDictionary dictionary : [String:AnyObject]) throws -> [VendingSelection:VendingItem] {
            var inventory: [VendingSelection:VendingItem] = [:]
            for(key , value) in dictionary {
                if let itemDictionary = value as? [String:Any] ,
                    let price = itemDictionary ["price"] as? Double ,
                    let quantity = itemDictionary ["quantity"] as? Int {
                    let item = Item(price : price , quantity:quantity)
                    guard let selection = VendingSelection(rawValue : key) else {
                    throw InventoryError.invalidSelection}
                inventory.updateValue(Item, forKey: selection)

} ```

4 Answers

Kayondo Martin
Kayondo Martin
7,481 Points

same problem here, says VendingSelection can not be constructed because it has no accessible initializers

Jeff McDivitt
Jeff McDivitt
23,970 Points

Could you give me a little more information on the error?

At a glance, it seems your return from the PlistConverter vendingInventory function doesn't exist and it needs to... try: return inventory just before the function's closing curly brace.

Chelsea Jackson
Chelsea Jackson
iOS Development with Swift Techdegree Student 130 Points

"selection" isn't recognized because your enum cases do not yet have raw values. You need to set the type for the enum as "String", which will default every case's raw value to the string name, and it should work.