ios - Bundle.preferredLocalizations 困惑

Question

3 preferredLocalizations的 Bundle太困惑了，我有很多问题:

1. 为什么 2 preferredLocalizations方法是类方法，但一直在谈论一些未指定特定的包，就好像它们是在某个个体上调用的一样Bundle实例？

   • preferredLocalizations(from:) : 到底是什么a bundle object和 the bundle ？

     1. Returns one or more localizations from the specified list that a bundle object would use to locate resources for the current user.

     2. An array of NSString objects, each of which specifies the language ID for a localization that the bundle supports.

   • preferred​Localizations(from:​for​Preferences:​) : 到底是什么the specified bundle和 the receiver’s bundle ？

     1. Returns the localizations that a bundle object would prefer, given the specified bundle and user’s language preferences.

     2. An array of NSString objects, each of which identifies a localization in the receiver’s bundle. These strings are ordered in the array according to the specified preferences and are taken from the strings in the localizations​Array parameter. If none of the user-preferred localizations are available in the bundle, this method returns one of the bundle localizations.

2. 为什么 preferredLocalizations(from: localizations)不会返回与 preferred​Localizations(from: localizations, ​for​Preferences:​ nil) 相同的结果？如上所述，阅读他们的文档并没有真正帮助。当然，它们看起来是这样设计的，但实际上不是这样设计的:

   // Locale.preferredLanguages: ["es-CN", "ja-CN", "zh-Hans-CN", "en-CN", "he-IL"].
   let localizations = ["de", "en", "es", "fr", "it"]
   print(Bundle.preferredLocalizations(from: localizations)) // ["en"]
   print(Bundle.preferredLocalizations(from: localizations, forPreferences: nil)) // ["es"]
   

Answer 1

引用文档不是很好； Technical Note 2418更好地解释了它。

具体是说

Note that Bundle.preferredLocalizations(from:) will restrict the results to localizations supported by Bundle.mainBundle(), or the return value of Bundle.mainBundle().localizations(). If you would like to match against a different set of language identifiers, use Bundle.preferredLocalizations(from:forPreferences:) which does not rely on mainBundle’s localizations and instead solely relies on the two arguments passed in.

所以，

• 如果您使用 Bundle.preferredLocalizations(from:)，您提供的本地化列表首先会根据为主包定义的本地化进行过滤 (Bundle.main.localizations).
• 如果您使用 Bundle.preferredLocalizations(from:forPreferences:)，它会与您提供的列表一起工作。

在您提供的示例中，Bundle.preferredLocalizations(from: localizations) 返回 ["en"]。这可能是因为您的应用没有定义任何版本的西类牙语(“es”)。如果您向项目添加西类牙语本地化，它应该返回 ["es"]，因为“es-CN”列在“en-CN”之前。