Displaying products

Basic Information

Let’s start with the simplest case: you have a single product.

You can retrieve all information about this product using the function InAppPurchase.getProductBy(). 

InAppPurchase.getProductBy(identifier: String) -> SKProduct?

This returns an SKProduct extended with helpful methods. Those are the most important:

  • productIdentifier: String - The string that identifies the product to the Apple AppStore.
  • localizedTitle: String - The name of the product, in the language of the device, as retrieved from the AppStore.
  • localizedDescription: String - A description of the product, in the language of the device, as retrieved from the AppStore.
  • localizedPrice: String - The cost of the product in the local currency (read-only property added by this library, available for OSX >= 10.13.2 and iOS >= 11.2).

Example

You can add a function similar to this to your view.

func refreshView() {
  guard let product: SKProduct = InAppPurchase.getProductBy(identifier: "my_product_id") else {
    self.titleLabel.text = "Product unavailable"
    return
  }
  self.titleLabel.text = product.localizedTitle
  self.descriptionLabel.text = product.localizedDescription
  self.priceLabel.text = product.localizedPrice
}

This example assumes titleLabel is a UILabel, etc.

Make sure to call this function when the view appears on screen, for instance by calling it from viewWillAppear.

override func viewWillAppear(_ animated: Bool) {
  self.refreshView()
}

Additional information for Auto-Renewable Subscriptions

For subscription products, you also have some data about subscription periods and introductory offers. (read-only property added by this library, available for OSX >= 10.13.2 and iOS >= 11.2)

  • func hasIntroductoryPriceEligible() -> Bool - The product has an introductory price the user is eligible to.
  • localizedSubscriptionPeriod: String? - The period of the subscription.
  • localizedIntroductoryPrice: String? - The cost of the introductory offer if available in the local currency.
  • localizedIntroductoryPeriod: String? - The subscription period of the introductory offer.
  • localizedIntroductoryDuration: String? - The duration of the introductory offer.

Example

func refreshView() {
  guard let product: SKProduct = InAppPurchase.getProductBy(identifier: "my_product_id") else {
    self.titleLabel.text = "Product unavailable"
    return
  }
  self.titleLabel.text = product.localizedTitle
  self.descriptionLabel.text = product.localizedDescription

  // Format price text. Example: "0,99€ / month for 3 months (then 3,99 € / month)"
  var priceText = "\(product.localizedPrice) / \(product.localizedSubscriptionPeriod!)"
  if product.hasIntroductoryPriceEligible() {
      if product.introductoryPrice!.numberOfPeriods == 1 {
          priceText = "\(product.localizedIntroductoryPrice!) for \(product.localizedIntroductoryDuration!)" +
          " (then \(priceText))"
      } else {
          priceText = "\(product.localizedIntroductoryPrice!) / \(product.localizedIntroductoryPeriod!)" +
          " for \(product.localizedIntroductoryDuration!) (then \(priceText))"
      }
  }
  self.priceLabel.text = priceText
}

Note: You have to import StoreKit wherever you use SKProduct.