Fix language change issue

Author: Jack251970

Flow.Launcher.Core/Plugin/PluginManager.cs

@@ -205,9 +205,6 @@ public static async Task InitializePluginsAsync()
                 }
             }
 
-            InternationalizationManager.Instance.AddPluginLanguageDirectories(GetPluginsForInterface<IPluginI18n>());
-            InternationalizationManager.Instance.ChangeLanguage(Ioc.Default.GetRequiredService<Settings>().Language);
-
             if (failedPlugins.Any())
             {
                 var failed = string.Join(",", failedPlugins.Select(x => x.Metadata.Name));

Flow.Launcher.Core/Resource/Internationalization.cs

@@ -67,9 +67,9 @@ private static string GetSystemLanguageCodeAtStartup()
             return DefaultLanguageCode;
         }
 
-        internal void AddPluginLanguageDirectories(IEnumerable<PluginPair> plugins)
+        private void AddPluginLanguageDirectories()
         {
-            foreach (var plugin in plugins)
+            foreach (var plugin in PluginManager.GetPluginsForInterface<IPluginI18n>())
             {
                 var location = Assembly.GetAssembly(plugin.Plugin.GetType()).Location;
                 var dir = Path.GetDirectoryName(location);
@@ -96,6 +96,32 @@ private void LoadDefaultLanguage()
             _oldResources.Clear();
         }
 
+        /// <summary>
+        /// Initialize language. Will change app language and plugin language based on settings.
+        /// </summary>
+        public async Task InitializeLanguageAsync()
+        {
+            // Get actual language
+            var languageCode = _settings.Language;
+            if (languageCode == Constant.SystemLanguageCode)
+            {
+                languageCode = SystemLanguageCode;
+            }
+
+            // Get language by language code and change language
+            var language = GetLanguageByLanguageCode(languageCode);
+
+            // Add plugin language directories first so that we can load language files from plugins
+            AddPluginLanguageDirectories();
+
+            // Change language
+            await ChangeLanguageAsync(language);
+        }
+
+        /// <summary>
+        /// Change language during runtime. Will change app language and plugin language & save settings.
+        /// </summary>
+        /// <param name="languageCode"></param>
         public void ChangeLanguage(string languageCode)
         {
             languageCode = languageCode.NonNull();
@@ -110,44 +136,45 @@ public void ChangeLanguage(string languageCode)
 
             // Get language by language code and change language
             var language = GetLanguageByLanguageCode(languageCode);
-            ChangeLanguage(language, isSystem);
-        }
 
-        private Language GetLanguageByLanguageCode(string languageCode)
-        {
-            var lowercase = languageCode.ToLower();
-            var language = AvailableLanguages.GetAvailableLanguages().FirstOrDefault(o => o.LanguageCode.ToLower() == lowercase);
-            if (language == null)
-            {
-                Log.Error($"|Internationalization.GetLanguageByLanguageCode|Language code can't be found <{languageCode}>");
-                return AvailableLanguages.English;
-            }
-            else
-            {
-                return language;
-            }
+            // Change language
+            _ = ChangeLanguageAsync(language);
+
+            // Save settings
+            _settings.Language = isSystem ? Constant.SystemLanguageCode : language.LanguageCode;
         }
 
-        private void ChangeLanguage(Language language, bool isSystem)
+        private async Task ChangeLanguageAsync(Language language)
         {
-            language = language.NonNull();
-
+            // Remove old language files and load language
             RemoveOldLanguageFiles();
             if (language != AvailableLanguages.English)
             {
                 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;
 
-            // Raise event after culture is set
-            _settings.Language = isSystem ? Constant.SystemLanguageCode : language.LanguageCode;
-            _ = Task.Run(() =>
+            // Raise event for plugins after culture is set
+            await Task.Run(UpdatePluginMetadataTranslations);
+        }
+
+        private static Language GetLanguageByLanguageCode(string languageCode)
+        {
+            var lowercase = languageCode.ToLower();
+            var language = AvailableLanguages.GetAvailableLanguages().FirstOrDefault(o => o.LanguageCode.ToLower() == lowercase);
+            if (language == null)
+            {
+                Log.Error($"|Internationalization.GetLanguageByLanguageCode|Language code can't be found <{languageCode}>");
+                return AvailableLanguages.English;
+            }
+            else
             {
-                UpdatePluginMetadataTranslations();
-            });
+                return language;
+            }
         }
 
         public bool PromptShouldUsePinyin(string languageCodeToSet)

Flow.Launcher/App.xaml.cs

@@ -132,13 +132,14 @@ await Stopwatch.NormalAsync("|App.OnStartup|Startup cost", async () =>
                 // Register ResultsUpdated event after all plugins are loaded
                 Ioc.Default.GetRequiredService<MainViewModel>().RegisterResultsUpdatedEvent();
 
-                // Change language after all plugins are initialized
-                // TODO: Clean InternationalizationManager.Instance and InternationalizationManager.Instance.GetTranslation in future
-                Ioc.Default.GetRequiredService<Internationalization>().ChangeLanguage(_settings.Language);
-
                 Http.Proxy = _settings.Proxy;
 
                 await PluginManager.InitializePluginsAsync();
+
+                // Change language after all plugins are initialized because we need to update plugin title based on their api
+                // TODO: Clean InternationalizationManager.Instance and InternationalizationManager.Instance.GetTranslation in future
+                await Ioc.Default.GetRequiredService<Internationalization>().InitializeLanguageAsync();
+
                 await imageLoadertask;
 
                 var window = new MainWindow();