How do I listen to restore purchase response in Storekit 2?

Question

I'm trying to restore an individual purchase under iOS 17 and StoreKit 2. After tapping the restore button I need to download a file to complete the necessary restore process.

How do I listen to a restored purchase to download the necessary file?

I'm starting the restore process with this code:

.toolbar {
    ToolbarItem {
        Button("Restore") {
            isRestoring = true
            Task.detached {
                defer { isRestoring = false }
                try await AppStore.sync()
            }
        }
        .disabled(isRestoring)
    }
}

When I tap the restore button the only thing it does is show an Alert with the message: "Sign in with Apple ID. Press OK to simulate authenthicating with an Apple ID [Enviroment: Xcode]" And nothing else happens.

I need to know when the process is complete to download a file.

Thank you!

Answer 1

I found this sample code on Apple's documentation (currentEntitlements) that worked for me.

func refreshPurchasedProducts() async {
    // Iterate through the user's purchased products.
    for await verificationResult in Transaction.currentEntitlements {
        switch verificationResult {
        case .verified(let transaction):
            // Check the type of product for the transaction
            // and provide access to the content as appropriate.
            ...
        case .unverified(let unverifiedTransaction, let verificationError):
            // Handle unverified transactions based on your
            // business model.
            ...
        }
    }
}