第一个元素标记空列表字符串。崩溃只发生在生产中。

Question

所以我一直在为这个神秘的问题(至少对我来说)发怒。它只发生在App上。我尽力检查了我的BookingViewModel代码，我确信不应该有崩溃，所以我做了一些清理，然后上传了一个新的构建到TestFlight，并再次发生崩溃。

下面是来自Fabric's Crashlytics的坠机日志的截图：

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还有一片堆叠痕迹：

#0. Crashed: com.apple.main-thread
0  libswiftCore.dylib             0x103e70314 swift_unknownRelease + 24
1  libswiftCore.dylib             0x103e37b5c swift_arrayDestroy + 68
2  libswiftCore.dylib             0x103c308c0 (Missing)
3  libswiftCore.dylib             0x103e40f04 swift_unownedCheck + 88
4  appname                        0x102940848 BookingViewModelBookingViewModelBooking first-element-marker  empty-list String (BookingViewModel.swift:167)

最后，我的BookingViewModel中有第167行的代码在crashlog中被描述了(我已经为这个问题编辑了代码，我删除了一些行，但想法仍然存在，也是为了使代码简短)：

init(_ booking: Booking, withCompleteInfoCompletion completeInfo: @escaping BookingViewModelCompleteInfoCompletion) {
        let createdDate = booking.createdAt ?? ""
        let username = booking.username ?? ""
        let firstName = booking.firstName ?? ""
        let lastName = booking.lastName ?? ""
        let age = booking.age ?? ""
        let birthdate = booking.birthdate ?? ""

        // Final values for completion

        let userDetails = "\(firstName) \(lastName) \(age) / \(birthdate)".condensedWhitespace

        // Booking Status and total amount

        var bookingStatus: BookingStatus = .forProcessing

        if let status = booking.status,
            let statusId = status.id,
            let newBookingStatus = BookingStatus(rawValue: statusId) {
            bookingStatus = newBookingStatus
        }

        var totalAmount: Double = 0.00

        if bookingStatus == .forPayment || bookingStatus == .paid || bookingStatus == .forConfirmation {
            if let amounts = booking.amount {
                for amount in amounts {
                    if let amountString = amount.amount,
                        let amountDouble = Double(amountString) {
                        totalAmount = totalAmount + amountDouble
                    }
                }
            }
        }

        self.subtotal = String(format: "%.2f", arguments: [totalAmount])

        // Payment Method

        var paymentType: PaymentType = .cod
        if let paymentMethod = booking.paymentMethod,
            let type = PaymentType(rawValue: paymentMethod) {
            paymentType = type
        }

        // Initial Total

        let initialTotal = "₱\(self.getTotalAmount(.paypal))"

        completeInfo(
            "₱\(self.subtotal)", // line 167
            userDetails
        )
    }

因此，问题是:当应用程序从app或Testlfight下载时，而不是在开发/调试模式(运行在Xcode中)时，应用程序如何会崩溃？

另外，在Also上模拟项目的状态是否可能(例如，我已经阅读了某人的答案，以便我可以将项目的代码签名更改为iOS Distribution)？

谢谢!

Answer 1

好的，如果有人被这样的问题窃听，在主线程中放置导致怪异崩溃的线会有所帮助！

我不知道为什么，也许我应该更多地检查代码。因此，我只需要将崩溃线插入主线程，如下所示：

DispatchQueue.main.async {
    self.bookingViewModel = BookingViewModel(self.booking, withCompleteInfoCompletion: {
    ....
    })
}

上面的评论对我有很大的帮助！