Question

启动时，某些设备上的iOS 13应用崩溃。该应用程序正在生产中，我已经在Xcode Organizer Crashs中看到了此问题。我不能在模拟器或任何物理设备上都重现此问题。

我想这与本地化有关。我使用“ AppleLanguages”键，并将选择的语言保存为数组。我在“用户默认设置”中将语言另存为：

static var language: Language {
    get {

        if UserDefaults.standard.bool(forKey: isLanguageSelectedKey) {
            if let languageCode = UserDefaults.standard.array(forKey: appleLanguagesKey)?.first,
                let language = Language(rawValue: languageCode as! String) {
                return language
            } else {

                return Language.someLanguage
            }
        } else {
            return Language.someLanguage
        }

    }

    set {
        guard language != newValue else {
            return
        }
        UserDefaults.standard.removeObject(forKey: appleLanguagesKey)
        UserDefaults.standard.synchronize()

        UserDefaults.standard.set([newValue.rawValue], forKey: appleLanguagesKey)

        UserDefaults.standard.synchronize()
    }

我在Xcode Organizer崩溃中看到的

Stacktrace是：

Last Exception Backtrace (0)
0   (null) in __exceptionPreprocess ()
-------------------------------------------------------
8   (null) in +[NSUserDefaults(NSUserDefaults) standardUserDefaults] ()
9   (null) in __45+[GMSx_GTMSessionFetcher fetcherUserDefaults]_block_invoke ()
10  (null) in _dispatch_client_callout ()
11  (null) in _dispatch_once_callout ()
12  (null) in +[GMSx_GTMSessionFetcher fetcherUserDefaults] ()
13  (null) in +[GMSx_GTMSessionFetcher fetchersForBackgroundSessions] ()
14  (null) in +[GMSx_GTMSessionFetcher load] ()
15  (null) in load_images ()
-------------------------------------------------------



Thread 1
0   (null) in __pthread_kill ()
-------------------------------------------------------
9   (null) in _dispatch_once_callout ()
10  (null) in +[GMSx_GTMSessionFetcher fetcherUserDefaults] ()
11  (null) in +[GMSx_GTMSessionFetcher fetchersForBackgroundSessions] ()
12  (null) in +[GMSx_GTMSessionFetcher load] ()
13  (null) in load_images ()
-------------------------------------------------------

Answer 1

我什么都没有，所以这里有些假设可能无法正确解决：

static var language: Language {
get {
        if UserDefaults.standard.bool(forKey: isLanguageSelectedKey),
             let languageCode = UserDefaults.standard.array(forKey: appleLanguagesKey)?.first as? string,
             let language = Language(rawValue: languageCode) {
                return language
        }
        // No language value found, so return someLanguage
        return Language.someLanguage

    }
set {
    guard language != newValue else {
        return
    }
    UserDefaults.standard.removeObject(forKey: appleLanguagesKey)
    UserDefaults.standard.set([newValue.rawValue], forKey: appleLanguagesKey)
}

做了什么？

languageCode现在已经安全地展开，以避免强制转换，否则可能导致崩溃
对if语句进行了重写，以使其更加简洁，并消除了导致Language.someLanguage返回的一种情况。
我删除了您的设置器中的synchonize()个呼叫

iOS 13 UserDefaults：某些设备启动时应用崩溃

1 个答案: