无法分配“Product.SubscriptionInfo.Status??”类型的值输入“Product.SubscriptionInfo.Status？”

Question

我正在尝试在我的项目中实现 StoreKit，特别是自动更新订阅，使用Apple 的实现 StoreSit2 示例。

我重构了 Apple 的项目，仅根据我的应用程序需要进行年度订阅。我在 Github 上上传了重构的项目。我完全按照项目设置进行了所有操作，但是，我在文件中收到此错误：Store 和 StatusInfoView 位于以下行： 在“Store”第 214 行：

subscriptionGroupStatus = try? await subscriptions.first?.subscription?.status.first?.state  

错误：

无法分配“Product.SubscriptionInfo.RenewalState??”类型的值 输入“RenewalState？” （又名 ‘可选’)

在“StatusInfoView”第 134 行：

 subscriptionStatus = try? await product.subscription?.status.last

错误：

无法分配“Product.SubscriptionInfo.Status??”类型的值到 输入“Product.SubscriptionInfo.Status？”

  Github 上的项目不会产生错误，它在我将文件复制粘贴到我的 Xcode 项目后显示。

我不知道如何修复值分配。

任何帮助将不胜感激

  @MainActor
    func updateCustomerProductStatus() async {
        var purchasedSubscriptions: [Product] = []

        //Iterate through all of the user's purchased products.
        for await result in Transaction.currentEntitlements {
            do {
                //Check whether the transaction is verified. If it isn’t, catch `failedVerification` error.
                let transaction = try checkVerified(result)

                //Check the `productType` of the transaction and get the corresponding product from the store.
                switch transaction.productType {

                case .autoRenewable:
                    if let subscription = subscriptions.first(where: { $0.id == transaction.productID }) {
                        purchasedSubscriptions.append(subscription)
                    }
                default:
                    break
                }
            } catch {
                print()
            }
        }



        //Update the store information with auto-renewable subscription products.
        self.purchasedSubscriptions = purchasedSubscriptions

        //Check the `subscriptionGroupStatus` to learn the auto-renewable subscription state to determine whether the customer
        //is new (never subscribed), active, or inactive (expired subscription). This app has only one subscription
        //group, so products in the subscriptions array all belong to the same group. The statuses that
        //`product.subscription.status` returns apply to the entire subscription group.
        //let storeProducts = try await Product.products(for: productIdToEmoji.keys)

        subscriptionGroupStatus = try? await subscriptions.first?.subscription?.status.first?.state
    }


struct StatusInfoView_Previews: PreviewProvider {
    @StateObject static var store = Store()
    @State static var subscription: Product?
    @State static var subscriptionStatus: Product.SubscriptionInfo.Status?
    
    static var previews: some View {
        Group {
            if let subscription, let subscriptionStatus {
                StatusInfoView(product: subscription, status: subscriptionStatus)
                    .environmentObject(store)
            }
        }
        .task {
            guard let product = store.purchasedSubscriptions.first else {
                return
            }
            subscription = product
            subscriptionStatus = try? await product.subscription?.status.last
        }
    }

Answer 1

我想通了。 Apple 的项目是用 Swift 5 编写的。当我重构代码并将其移动到我的项目（用 Swift 4 编写）时，它抛出了语法错误。 我将项目更新到 Swift 5，错误消失了。