Fix WinForm Culture Info Issue

Flow.Launcher.Core/Resource/Internationalization.cs

@@ -1,16 +1,17 @@
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.IO;
 using System.Linq;
 using System.Reflection;
+using System.Threading;
+using System.Threading.Tasks;
 using System.Windows;
+using CommunityToolkit.Mvvm.DependencyInjection;
 using Flow.Launcher.Core.Plugin;
 using Flow.Launcher.Infrastructure;
 using Flow.Launcher.Infrastructure.UserSettings;
 using Flow.Launcher.Plugin;
-using System.Globalization;
-using System.Threading.Tasks;
-using CommunityToolkit.Mvvm.DependencyInjection;
 
 namespace Flow.Launcher.Core.Resource
 {
@@ -29,13 +30,12 @@
         private readonly Settings _settings;
         private readonly List<string> _languageDirectories = new();
         private readonly List<ResourceDictionary> _oldResources = new();
-        private readonly string SystemLanguageCode;
+        private static string SystemLanguageCode;
 
         public Internationalization(Settings settings)
         {
             _settings = settings;
             AddFlowLauncherLanguageDirectory();
-            SystemLanguageCode = GetSystemLanguageCodeAtStartup();
         }
 
         private void AddFlowLauncherLanguageDirectory()
@@ -44,7 +44,7 @@
             _languageDirectories.Add(directory);
         }
 
-        private static string GetSystemLanguageCodeAtStartup()
+        public static void InitSystemLanguageCode()
         {
             var availableLanguages = AvailableLanguages.GetAvailableLanguages();
 
@@ -65,11 +65,11 @@
                     string.Equals(languageCode, threeLetterCode, StringComparison.OrdinalIgnoreCase) ||
                     string.Equals(languageCode, fullName, StringComparison.OrdinalIgnoreCase))
                 {
-                    return languageCode;
+                    SystemLanguageCode = languageCode;
                 }
             }
 
-            return DefaultLanguageCode;
+            SystemLanguageCode = DefaultLanguageCode;
         }
 
         private void AddPluginLanguageDirectories()
@@ -173,15 +173,33 @@
                 LoadLanguage(language);
             }
 
-            // Culture of main thread
-            // Use CreateSpecificCulture to preserve possible user-override settings in Windows, if Flow's language culture is the same as Windows's
-            CultureInfo.CurrentCulture = CultureInfo.CreateSpecificCulture(language.LanguageCode);
-            CultureInfo.CurrentUICulture = CultureInfo.CurrentCulture;
+            // Change culture info
+            ChangeCultureInfo(language.LanguageCode);
 
             // Raise event for plugins after culture is set
             await Task.Run(UpdatePluginMetadataTranslations);
         }
 
+        public static void ChangeCultureInfo(string languageCode)
+        {
+            // Culture of main thread
+            // Use CreateSpecificCulture to preserve possible user-override settings in Windows, if Flow's language culture is the same as Windows's
+            CultureInfo currentCulture;
+            try
+            {
+                currentCulture = CultureInfo.CreateSpecificCulture(languageCode);
+            }
+            catch (CultureNotFoundException)
+            {
+                currentCulture = CultureInfo.CreateSpecificCulture(SystemLanguageCode);
+            }
+            CultureInfo.CurrentCulture = currentCulture;
+            CultureInfo.CurrentUICulture = currentCulture;
+            var thread = Thread.CurrentThread;
+            thread.CurrentCulture = currentCulture;
+            thread.CurrentUICulture = currentCulture;
+        }
+
         public bool PromptShouldUsePinyin(string languageCodeToSet)
         {
             var languageToSet = GetLanguageByLanguageCode(languageCodeToSet);
@@ -196,7 +214,7 @@
             // "Do you want to search with pinyin?"
             string text = languageToSet == AvailableLanguages.Chinese ? "是否启用拼音搜索？" : "是否啓用拼音搜索？" ;
 
             if (Ioc.Default.GetRequiredService<IPublicAPI>().ShowMsgBox(text, string.Empty, MessageBoxButton.YesNo) == MessageBoxResult.No)
                 return false;
 
             return true;

Flow.Launcher.Infrastructure/UserSettings/Settings.cs

@@ -25,7 +25,13 @@
 
         public void Initialize()
         {
+            // Initialize dependency injection instances after Ioc.Default is created
             _stringMatcher = Ioc.Default.GetRequiredService<StringMatcher>();
+
+            // Initialize application resources after application is created
+            var settingWindowFont = new FontFamily(SettingWindowFont);
+            Application.Current.Resources["SettingWindowFont"] = settingWindowFont;
+            Application.Current.Resources["ContentControlThemeFontFamily"] = settingWindowFont;
         }
 
         public void Save()
@@ -115,8 +121,11 @@
                 {
                     _settingWindowFont = value;
                     OnPropertyChanged();
-                    Application.Current.Resources["SettingWindowFont"] = new FontFamily(value);
-                    Application.Current.Resources["ContentControlThemeFontFamily"] = new FontFamily(value);
+                    if (Application.Current != null)
+                    {
+                        Application.Current.Resources["SettingWindowFont"] = new FontFamily(value);
+                        Application.Current.Resources["ContentControlThemeFontFamily"] = new FontFamily(value);
+                    }
                 }
             }
         }

Flow.Launcher/App.xaml.cs

@@ -41,9 +41,9 @@
         private static readonly string ClassName = nameof(App);
 
         private static bool _disposed;
+        private static Settings _settings;
         private static MainWindow _mainWindow;
         private readonly MainViewModel _mainVM;
-        private readonly Settings _settings;
 
         // To prevent two disposals running at the same time.
         private static readonly object _disposingLock = new();
@@ -55,19 +55,7 @@
         public App()
         {
             // Initialize settings
-            try
-            {
-                var storage = new FlowLauncherJsonStorage<Settings>();
-                _settings = storage.Load();
-                _settings.SetStorage(storage);
-                _settings.WMPInstalled = WindowsMediaPlayerHelper.IsWindowsMediaPlayerInstalled();
-            }
-            catch (Exception e)
-            {
-                ShowErrorMsgBoxAndFailFast("Cannot load setting storage, please check local data directory", e);
-                return;
-            }
-
+            _settings.WMPInstalled = WindowsMediaPlayerHelper.IsWindowsMediaPlayerInstalled();
             // Configure the dependency injection container
             try
             {
@@ -103,7 +91,7 @@
                         .AddTransient<SelectBrowserViewModel>()
                         .AddTransient<SelectFileManagerViewModel>()
                     ).Build();
                 Ioc.Default.ConfigureServices(host.Services);
             }
             catch (Exception e)
             {
@@ -123,16 +111,6 @@
                 ShowErrorMsgBoxAndFailFast("Cannot initialize api and settings, please open new issue in Flow.Launcher", e);
                 return;
             }
-
-            // Local function
-            static void ShowErrorMsgBoxAndFailFast(string message, Exception e)
-            {
-                // Firstly show users the message
-                MessageBox.Show(e.ToString(), message, MessageBoxButton.OK, MessageBoxImage.Error);
-
-                // Flow cannot construct its App instance, so ensure Flow crashes w/ the exception info.
-                Environment.FailFast(message, e);
-            }
         }
 
         #endregion
@@ -142,6 +120,29 @@
         [STAThread]
         public static void Main()
         {
+            // Initialize settings so that we can get language code
+            try
+            {
+                var storage = new FlowLauncherJsonStorage<Settings>();
+                _settings = storage.Load();
+                _settings.SetStorage(storage);
+            }
+            catch (Exception e)
+            {
+                ShowErrorMsgBoxAndFailFast("Cannot load setting storage, please check local data directory", e);
+                return;
+            }
+
+            // Initialize system language before changing culture info
+            Internationalization.InitSystemLanguageCode();
+
+            // Change culture info before application creation to localize WinForm windows
+            if (_settings.Language != Constant.SystemLanguageCode)
+            {
+                Internationalization.ChangeCultureInfo(_settings.Language);
+            }
+
+            // Start the application as a single instance
             if (SingleInstance<App>.InitializeAsFirstInstance())
             {
                 using var application = new App();
@@ -152,6 +153,19 @@
 
         #endregion
 
+        #region Fail Fast
+
+        private static void ShowErrorMsgBoxAndFailFast(string message, Exception e)
+        {
+            // Firstly show users the message
+            MessageBox.Show(e.ToString(), message, MessageBoxButton.OK, MessageBoxImage.Error);
+
+            // Flow cannot construct its App instance, so ensure Flow crashes w/ the exception info.
+            Environment.FailFast(message, e);
+        }
+
+        #endregion
+
         #region App Events
 
 #pragma warning disable VSTHRD100 // Avoid async void methods
@@ -196,7 +210,7 @@
                 // Change language after all plugins are initialized because we need to update plugin title based on their api
                 await Ioc.Default.GetRequiredService<Internationalization>().InitializeLanguageAsync();
 
                 await imageLoadertask;
 
                 _mainWindow = new MainWindow();
 
@@ -222,7 +236,7 @@
             });
         }
 
 #pragma warning restore VSTHRD100 // Avoid async void methods
 
         /// <summary>
         /// Check startup only for Release