Storekit 和处理已购买 IAP 的用户

Question

我在关注this RW 教程，和很多IAP 和Storekit 教程一样，他们第一次谈论用户购买IAP 的流程，但他们没有详细说明如何当已购买 IAP 的用户再次打开该应用时，该应用运行。

当我找到问题的关键时更新我的​​问题：

据我所知，阻止/显示内容的代码是查找 (1) 收据和 (2) SessionID ...他在教程中没有详细说明 SessionID 是什么对于或是否仅作为本教程演示的一部分。例如，它仅在调用 uploadReceipt 时设置（仅在调用 handlePurchasedState 或 handleRestoredState 时调用）。换句话说，如果用户打开已经订阅的应用程序，则没有运行代码来设置SessionID，因此内容永远不会解锁？

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

  var window: UIWindow?

  func application(_ application: UIApplication,
                   didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {

    SKPaymentQueue.default().add(self)
    SubscriptionService.shared.loadSubscriptionOptions()
    return true
  }  
}


// MARK: - SKPaymentTransactionObserver

extension AppDelegate: SKPaymentTransactionObserver {

  func paymentQueue(_ queue: SKPaymentQueue,
                    updatedTransactions transactions: [SKPaymentTransaction]) {

    for transaction in transactions {
      switch transaction.transactionState {
      case .purchasing:
        handlePurchasingState(for: transaction, in: queue)
      case .purchased:
        handlePurchasedState(for: transaction, in: queue)
      case .restored:
        handleRestoredState(for: transaction, in: queue)
      case .failed:
        handleFailedState(for: transaction, in: queue)
      case .deferred:
        handleDeferredState(for: transaction, in: queue)
      }
    }
  }

  func handlePurchasingState(for transaction: SKPaymentTransaction, in queue: SKPaymentQueue) {
    print("User is attempting to purchase product id: \(transaction.payment.productIdentifier)")
  }

  func handlePurchasedState(for transaction: SKPaymentTransaction, in queue: SKPaymentQueue) {
    print("User purchased product id: \(transaction.payment.productIdentifier)")

    queue.finishTransaction(transaction)
    SubscriptionService.shared.uploadReceipt { (success) in
      DispatchQueue.main.async {
        NotificationCenter.default.post(name: SubscriptionService.purchaseSuccessfulNotification, object: nil)
      }
    }
  }

  func handleRestoredState(for transaction: SKPaymentTransaction, in queue: SKPaymentQueue) {
    print("Purchase restored for product id: \(transaction.payment.productIdentifier)")
    queue.finishTransaction(transaction)
    SubscriptionService.shared.uploadReceipt { (success) in
      DispatchQueue.main.async {
        NotificationCenter.default.post(name: SubscriptionService.restoreSuccessfulNotification, object: nil)
      }
    }
  }

  func handleFailedState(for transaction: SKPaymentTransaction, in queue: SKPaymentQueue) {
    print("Purchase failed for product id: \(transaction.payment.productIdentifier)")
  }

  func handleDeferredState(for transaction: SKPaymentTransaction, in queue: SKPaymentQueue) {
    print("Purchase deferred for product id: \(transaction.payment.productIdentifier)")
  }
}

Answer 1

您不会在每次用户启动应用时收到购买通知，但从技术上讲，您可以在每次程序运行时验证应用收据并重新处理每个 IAP。这似乎效率低下。您的应用程序应该在购买时跟踪已购买的内容。

如果该应用曾被删除并重新安装，或者如果用户将其安装在另一台设备上，您应该提供“恢复应用内购买”功能来刷新应用收据并进行验证。