StoreKit

Overview

StoreKit is an Apple framework that supports in-app purchases, ad network attribution, Apple Music integration, and enabling app ratings and reviews.

Resources

Usage

To use StoreKit in an app:

  1. Select File ... New ... File... or press cmd-n.

  2. Scroll the "Other" category.

  3. Select "StoreKit Configuration File".

  4. A file name can be entered, but the default name of "Configuration.storekit" is fine.

  5. Click the "+" in the lower-left of the editor and select a type. For one-time purchases, select "Add Non-Consumable In-App Purchase".

  6. Enter a "Reference Name". This can be the app name. To find this, click the top entry in the Navigator, select the "General" tab, and note the value of Identity ... Display Name.

  7. Enter a "Product ID". This can be the project bundle identifier. To find this, click the top entry in the Navigator, select the "General" tab, and note the value of Identity ... Bundle Identifier.

  8. Enter a price.

  9. Under "Localizations", double-click an option such as "English (U.S.)".

  10. Enter a "Display Name". This can be the same as the Reference Name entered above.

  11. Enter a "Description" of the purchasable item.

  12. Click "+" under "Localizations" to add more supported locales.

  13. Repeat steps 5-12 for each additional non-consumable that can be purchased.

  14. Create a new Swift file. A good name is StoreKit.swift.

  15. Add the following in StoreKitStore.swift:

     import StoreKit

     class StoreKitStore: NSObject, ObservableObject {
         // This is a Set of purchasable product ids.
         private var allProductIdentifiers =
             Set(["r.mark.volkmann.gmail.com.GiftTrack"])

         private var productsRequest: SKProductsRequest?

         private var fetchedProducts: [SKProduct] = []

         typealias CompletionHandler = ([SKProduct]) -> Void

         private var completionHandler: CompletionHandler?

         override init() {
             super.init()
             fetchProducts { products in
                 print("products =", products)
             }
         }

         private func fetchProducts(
             _ completion: @escaping CompletionHandler
         ) {
             guard productsRequest == nil else { return }
             completionHandler = completion
             productsRequest =
                 SKProductsRequest(productIdentifiers: allProductIdentifiers)
             productsRequest?.delegate = self
             productsRequest?.start()
         }
     }

     extension StoreKitStore: SKProductsRequestDelegate {
         func productsRequest(
             _ request: SKProductsRequest,
             didReceive response: SKProductsResponse
         ) {
             let loadedProducts = response.products
             let invalidProducts = response.invalidProductIdentifiers
             guard !loadedProducts.isEmpty else {
                 print("failed to load products")
                 if !invalidProducts.isEmpty {
                     print("invalid products found: \(invalidProducts)")
                 }
                 productsRequest = nil
                 return
             }

             // Cache the fetched products.
             fetchedProducts = loadedProducts

             // Notify listeners of loaded products.
             DispatchQueue.main.async {
                 self.completionHandler?(loadedProducts)
                 self.completionHandler = nil
                 self.productsRequest = nil
             }
         }
     }

  16. In the {app-name}.swift file, add the following inside the struct that inherits from App:

    @StateObject private var store = StoreKitStore()

  17. In any views that need to access the store, add the following:

    @EnvironmentObject private var store: StoreKitStore

  18. In the Navigator, select {app-name}.swift.

  19. In the top bar, click the project name to the left of the device drop-down and select "Edit Scheme..." which opens a dialog.

  20. Click "Run" in the dialog left nav.

  21. Click the "Options" tab.

  22. Change the value of "StoreKit Configuration" from "None" to "Configuration.storekit".

  23. Click the "Close" button.

Displaying Products

To display products in SwiftUI, get an array of product ids where each is a String and pass it to the StoreView view.

StoreView(ids: productIds)

This produces a UI that works on all platforms including iOS, iPadOS, macOS, and watchOS.

This is best tested in the Simulator rather than in Previews.

The productViewStyle view modifier can be applied to StoreView to change the size and layout of each product section. It takes one argument which can be .regular (default), .large, or .compact. The .large option has an issue with horizontal alignment.

Testing from Xcode

Xcode and the Simulator can be used to test in-app purchases without the need to configure them in AppStoreConnect. See the YouTube video How to easily test InApp Purchases in an iOS app with Josh Holtz.

To create a StoreKit configuration file to be used for testing:

  1. Select File ... New ... File...
  2. Select "StoreKit Configuration File" and click the "Next" button.
  3. Enter a name like "Test". The file will have an extension of .storekit.
  4. If you have already described the products in AppStoreConnect, check the "Sync this file with an app in App Store Connect" checkbox.
  5. Click the "Next" button.
  6. Select the top project directory that contains the main .swift file.
  7. Click the "Create" button.

To describe products in the new StoreKit configuration file:

  1. In the special editor that opens for the new StoreKit configuration file, for each product to be offered by the app:

    1. Click the "+" in the lower-left and select a kind of product to add such as "Add Non-Consumable In-App Purchase".
    2. Enter a "Reference Name" that describes the product.
    3. Enter a product ID that is unique among all of your apps. It could be the app bundle ID followed by a product-specific identifier.
    4. Enter a price.
    5. Optionally select "On" for "Family Sharing".
    6. Expand the "Localizations" section.
    7. For each language to be supported, enter a "Display Name" and "Description" for the product.

To tell the Simulator to use this new .storekit configuration file:

  1. Click the dropdown to the left of the device dropdown at the top of the Xcode window.
  2. Select "Edit Scheme..."
  3. In the left nav, select "Run".
  4. Select the "Options" tab.
  5. Change the value selected in the "StoreKit Configuration" dropdown to the name of the new .storekit configuration file.
  6. Click the "Close" button.

To test an in-app purchase:

  1. Run the app in the Simulator and make an in-app purchase.
  2. If the products do not appear in the app, try running it again.
  3. In Xcode, select Debug ... StoreKit ... Manage Transactions... to see a history of all the in-app purchase transactions.
  4. Right-click a transaction to get a menu with the options "Approve Transaction", "Decline Transaction", "Refund Purchase", "Resolve Issue", "Request Price Increase Consent", and "Delete Transaction".
  5. For subscriptions, click the "Subscription Options" button below a transaction to get a dialog where the subscription can be cancelled.

Example Project

See StoreKitDemo which is not yet fully functional. StoreKit still seems difficult to correctly configure and use!