Need help implementing in-app purchase from helper class - swift

Question

I am trying IAP for the first time and I need some help connecting the dots.
My app has two different non-consumable IAPs which I have set up in a "product" class if its own like this:
enum IAPProduct: String{
case tempoLevels = ".....TempoLevels"
case timingLevels = ".....TimingLevels"
}
Then I set up a helper class via a tutorial I found like this:
class IAPService: NSObject {
private override init() {}
static let shared = IAPService()
var products = [SKProduct]()
let paymentQueue = SKPaymentQueue.default()
func getProducts() {
let products: Set = [IAPProduct.tempoLevels.rawValue, IAPProduct.timingLevels.rawValue]
let request = SKProductsRequest(productIdentifiers: products)
request.delegate = self
request.start()
paymentQueue.add(self)
}
func purchase(product: IAPProduct) {
guard let productToPurchase = products.filter({ $0.productIdentifier == product.rawValue }).first
else {return}
let payment = SKPayment(product: productToPurchase)
paymentQueue.add(payment)
}
}
extension IAPService: SKProductsRequestDelegate {
func productsRequest(_ request: SKProductsRequest, didReceive response: SKProductsResponse) {
self.products = response.products
for product in response.products {
print(product.localizedTitle)
}
}
}
extension IAPService: SKPaymentTransactionObserver {
func paymentQueue(_ queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction]) {
for transaction in transactions {
print(transaction.transactionState.status(), transaction.payment.productIdentifier)
switch transaction.transactionState {
case .purchasing: break
default: queue.finishTransaction(transaction)
}
}
}
}
extension SKPaymentTransactionState {
func status() -> String{
switch self{
case .deferred: return "deferred"
case .failed: return "failed"
case .purchased: return "purchased"
case .purchasing: return "purchasing"
case .restored: return "restored"
#unknown default:
return("Something is wrong...")
}
}
}
I would like to trigger some functions in another view controller when the product is purchased. How do I do this?
I sort of set up a function in one of the view controllers that checks UserDefaults in one of the view controllers like this:
func isPurchased() -> Bool {
let purchaseStatus = UserDefaults.standard.bool(forKey: ??)
if purchaseStatus == true {
print("Previously purchased!")
return true
}else{
print("Never purchased!")
return false
}
}
I'm not sure how I can use this function, but if I can somehow, I have code in my app that would work with it if at all possible.

Answer 1

You can use directly SKPaymentTransactionState for purchase checking.
You can call like thi after creating the transaction if want to Bool value
func isPurchased(transaction: SKPaymentTransaction) -> Bool {
return transaction.transactionState == .purchased
}
or directly String value from extension ofSKPaymentTransactionState
func isPurchased(transaction: SKPaymentTransaction) -> String {
return transaction.status
}
In the mean time, you should not ever store a boolean for checking if user has bought in-app purchase in UserDefaults. User can change it very easily (without jailbreaking) and get your goodies for free! You should Use Keychain instead of UserDefaults.