如何检测应用内购买关闭并完成购买的警报弹出

我实现了应用内购买,但无法检测到用户何时关闭警报并完成购买。我想检查他们,如果他们购买了一个项目,我想显示日志“购买”在控制台上。

现在 case .purchased : 在里面 func paymentQueue

    func paymentQueue(_ queue: SKPaymentQueue, updatedTransactions transactions: [SKPaymentTransaction]) {
        for transaction in transactions {
            switch transaction.transactionState {
            case .purchasing :
                break
            case .purchased :
                // always through here even user doesn't purchase items
                completeTransaction(transaction: transaction)

                print("purchased")

            case .failed :
                failedTransaction(transaction: transaction)
            case .restored :
                restoreTransaction(transaction: transaction)
            case .deferred :
                deferredTransaction(transaction: transaction)
            }
        }
    }