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Start your free trialNila Palmo Ram
4,303 PointsError: Cannot convert value of type 'Int' to expected argument type 'Double?'
import UIKit
fileprivate let reuseIdentifier = "vendingItem" fileprivate let screenWidth = UIScreen.main.bounds.width
class ViewController: UIViewController, UICollectionViewDataSource, UICollectionViewDelegate {
@IBOutlet weak var collectionView: UICollectionView!
@IBOutlet weak var totalLabel: UILabel!
@IBOutlet weak var balanceLabel: UILabel!
@IBOutlet weak var quantityLabel: UILabel!
@IBOutlet weak var priceLabel: UILabel!
@IBOutlet weak var quantityStepper: UIStepper!
let vendingMachine: VendingMachine
var currentSelection: VendingSelection?
required init?(coder aDecoder: NSCoder) {
do {
let dictionary = try PlistConverter.dictionary(fromFile: "VendingInventory", ofType: "plist")
let inventory = try InventoryUnarchiver.vendingInventory(fromDictionary: dictionary)
self.vendingMachine = FoodVendingMachine(inventory: inventory)
} catch let error {
fatalError("\(error)")
}
super.init(coder: aDecoder)
}
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
setupCollectionViewCells()
updateDisplayWith(balance: vendingMachine.amountDeposited, totalPrice: 0, itemPrice: 0, itemQuantity: 1)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
// MARK: - Setup
func setupCollectionViewCells() {
let layout = UICollectionViewFlowLayout()
layout.sectionInset = UIEdgeInsets(top: 0, left: 0, bottom: 20, right: 0)
let padding: CGFloat = 10
let itemWidth = screenWidth/3 - padding
let itemHeight = screenWidth/3 - padding
layout.itemSize = CGSize(width: itemWidth, height: itemHeight)
layout.minimumLineSpacing = 10
layout.minimumInteritemSpacing = 10
collectionView.collectionViewLayout = layout
}
//MARK: - Vending Machine
@IBAction func purchase() {
if let currentSelection = currentSelection {
do {
try vendingMachine.vend(selection: currentSelection, quantity: Int(quantityStepper.value))
updateDisplayWith(balance: vendingMachine.amountDeposited, totalPrice: 0.0, itemPrice: 0, itemQuantity: 1)
} catch VendingMachineError.outOfStock {
showAlertWith(title: "Out of stock", message: "This item is unavailable. Please make another selection")
} catch VendingMachineError.invalidSelection {
showAlertWith(title: "Invalid selection", message: "Please make another selection")
} catch VendingMachineError.insufficientFunds(let required) {
let message = "You need ₹\(required) to complete the transaction"
} catch let error {
fatalError("\(error)")
}
if let indexPath = collectionView.indexPathsForSelectedItems?.first {
collectionView.deselectItem(at: indexPath, animated: true)
updateCell(having: indexPath, selected: false)
}
} else {
// FIXME: Alert user no selection
}
}
func updateDisplayWith(balance: Double? = nil, totalPrice: Double? = nil, itemPrice: Double? = nil, itemQuantity: Double? = nil) {
if let balanceValue = balance {
balanceLabel.text = "₹\(balanceValue)"
}
if let totalValue = totalPrice {
totalLabel.text = "₹\(totalValue)"
}
if let priceValue = itemPrice {
priceLabel.text = "₹\(priceValue)"
}
if let quantityValue = itemQuantity {
quantityLabel.text = "\(quantityValue)"
}
}
func updateTotalPrice(for item: VendingItem) {
let totalPrice = item.price * quantityStepper.value
updateDisplayWith(totalPrice: totalPrice)
}
@IBAction func updateValue(_ sender: UIStepper) {
let quantity = Int(quantityStepper.value)
updateDisplayWith(itemQuantity: quantity)
if let currentSelection = currentSelection, let item = vendingMachine.item(forSelection: currentSelection) {
updateTotalPrice(for: item)
}
}
1 Answer
Brandon Mahoney
iOS Development with Swift Techdegree Graduate 30,149 PointsYou are converting to Int here from Double and then trying to pass it into a parameter of type Double. Just don't convert it to Int.
@IBAction func updateValue(_ sender: UIStepper) {
let quantity = Int(quantityStepper.value)
updateDisplayWith(itemQuantity: quantity)
if let currentSelection = currentSelection, let item = vendingMachine.item(forSelection: currentSelection) {
updateTotalPrice(for: item)
}
}
Change to:
@IBAction func updateValue(_ sender: UIStepper) {
updateDisplayWith(itemQuantity: quantityStepper.value)
if let currentSelection = currentSelection, let item = vendingMachine.item(forSelection: currentSelection) {
updateTotalPrice(for: item)
}
}
Nila Palmo Ram
4,303 PointsNila Palmo Ram
4,303 PointsThank u!!