Bug 56026 - Localization doesn't work using "Bundle Assemblies into Native Code" in release mode
Summary: Localization doesn't work using "Bundle Assemblies into Native Code" in relea...
Status: RESOLVED DUPLICATE of bug 55603
Alias: None
Product: Android
Classification: Xamarin
Component: General ()
Version: unspecified
Hardware: PC Windows
: --- normal
Target Milestone: ---
Assignee: Jonathan Pryor
Depends on:
Reported: 2017-05-05 10:03 UTC by batmaci
Modified: 2017-05-05 15:47 UTC (History)
3 users (show)

Is this bug a regression?: ---
Last known good build:

android configuration screenshot (27.24 KB, image/png)
2017-05-05 10:03 UTC, batmaci

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Description batmaci 2017-05-05 10:03:05 UTC
Created attachment 21970 [details]
android configuration screenshot

I followed the https://developer.xamarin.com/guides/xamarin-forms/advanced/localization/ and using resx files with displaying correct language, with DI on Android, I am able to change language within my app. 
Basically in Android, I added platform specific code as described in the article

    namespace UsingResxLocalization.Android
        public class Localize : UsingResxLocalization.ILocalize
            public void SetLocale(CultureInfo ci)
                Thread.CurrentThread.CurrentCulture = ci;
                Thread.CurrentThread.CurrentUICulture = ci;
            public CultureInfo GetCurrentCultureInfo()
                var netLanguage = "en";
                var androidLocale = Java.Util.Locale.Default;
                netLanguage = AndroidToDotnetLanguage(androidLocale.ToString().Replace("_", "-"));
                // this gets called a lot - try/catch can be expensive so consider caching or something
                System.Globalization.CultureInfo ci = null;
                    ci = new System.Globalization.CultureInfo(netLanguage);
                catch (CultureNotFoundException e1)
                    // iOS locale not valid .NET culture (eg. "en-ES" : English in Spain)
                    // fallback to first characters, in this case "en"
                        var fallback = ToDotnetFallbackLanguage(new PlatformCulture(netLanguage));
                        ci = new System.Globalization.CultureInfo(fallback);
                    catch (CultureNotFoundException e2)
                        // iOS language not valid .NET culture, falling back to English
                        ci = new System.Globalization.CultureInfo("en");
                return ci;
            string AndroidToDotnetLanguage(string androidLanguage)
                var netLanguage = androidLanguage;
                //certain languages need to be converted to CultureInfo equivalent
                switch (androidLanguage)
                    case "ms-BN":   // "Malaysian (Brunei)" not supported .NET culture
                    case "ms-MY":   // "Malaysian (Malaysia)" not supported .NET culture
                    case "ms-SG":   // "Malaysian (Singapore)" not supported .NET culture
                        netLanguage = "ms"; // closest supported
                    case "in-ID":  // "Indonesian (Indonesia)" has different code in  .NET
                        netLanguage = "id-ID"; // correct code for .NET
                    case "gsw-CH":  // "Schwiizertüütsch (Swiss German)" not supported .NET culture
                        netLanguage = "de-CH"; // closest supported
                        // add more application-specific cases here (if required)
                        // ONLY use cultures that have been tested and known to work
                return netLanguage;
            string ToDotnetFallbackLanguage(PlatformCulture platCulture)
                var netLanguage = platCulture.LanguageCode; // use the first part of the identifier (two chars, usually);
                switch (platCulture.LanguageCode)
                    case "gsw":
                        netLanguage = "de-CH"; // equivalent to German (Switzerland) for this app
                        // add more application-specific cases here (if required)
                        // ONLY use cultures that have been tested and known to work
                return netLanguage;

In PCL code I have 


    namespace myApp.Resx
        /// <summary>
        /// Implementations of this interface MUST convert iOS and Android
        /// platform-specific locales to a value supported in .NET because
        /// ONLY valid .NET cultures can have their RESX resources loaded and used.
        /// </summary>
        /// <remarks>
        /// Lists of valid .NET cultures can be found here:
        ///   http://www.localeplanet.com/dotnet/
        ///   http://www.csharp-examples.net/culture-names/
        /// You should always test all the locales implemented in your application.
        /// </remarks>
        public interface ILocalize
            ///	<summary>
            /// This method must evaluate platform-specific locale settings
            /// and convert them (when necessary) to a valid .NET locale.
            /// </summary>
            CultureInfo GetCurrentCultureInfo();
            /// <summary>
            /// CurrentCulture and CurrentUICulture must be set in the platform project, 
            /// because the Thread object can't be accessed in a PCL.
            /// </summary>
            void SetLocale(CultureInfo ci);
        /// <summary>
        /// Helper class for splitting locales like
        ///   iOS: ms_MY, gsw_CH
        ///   Android: in-ID
        /// into parts so we can create a .NET culture (or fallback culture)
        /// </summary>
        public class PlatformCulture
            public PlatformCulture(string platformCultureString)
                if (String.IsNullOrEmpty(platformCultureString))
                    throw new ArgumentException("Expected culture identifier", "platformCultureString"); // in C# 6 use nameof(platformCultureString)
                PlatformString = platformCultureString.Replace("_", "-"); // .NET expects dash, not underscore
                var dashIndex = PlatformString.IndexOf("-", StringComparison.Ordinal);
                if (dashIndex > 0)
                    var parts = PlatformString.Split('-');
                    LanguageCode = parts[0];
                    LocaleCode = parts[1];
                    LanguageCode = PlatformString;
                    LocaleCode = "";
            public string PlatformString { get; private set; }
            public string LanguageCode { get; private set; }
            public string LocaleCode { get; private set; }
            public override string ToString()
                return PlatformString;

then in my PCL code, I am able to overwrite the culture with the code below

      string name = Helpers.Settings.PreferredLanguage == "en" ? "en-US" : Helpers.Settings.PreferredLanguage + "-" + Helpers.Settings.PreferredLanguage.ToUpper();
                            currentCultureInfo = new System.Globalization.CultureInfo(name);
                    Resx.AppRes.Culture = currentCultureInfo;

This Code implementation works fine when I run in Debug and Release Mode.
But It fails working in Release Mode using "Bundle Assemblies into Native Code". 
when I enable, "Enable developer instrumentation" in Release mode, It works also.
If I remove the check for this option, It works fine.

What could be the possible problem? I dont know how to track this down. I tried using Android Device Monitor but it doesnt display much for it. 

configuration looks like as attached image. 

I haven't tried but I am guessing that you will have same problem using localization sample in the documentation. because I have just copied code from there without changing it.
Comment 1 Brendan Zagaeski (Xamarin Team, assistant) 2017-05-05 15:47:12 UTC

*** This bug has been marked as a duplicate of bug 55603 ***