[Enhancement] Support for more than one resource manager

samples/XCT.Sample/App.xaml.cs

@@ -15,8 +15,7 @@ public App()
 			On<Windows>().SetImageDirectory("Assets");
 
 			LocalizationResourceManager.Current.PropertyChanged += (sender, e) => AppResources.Culture = LocalizationResourceManager.Current.CurrentCulture;
-			LocalizationResourceManager.Current.Init(AppResources.ResourceManager);
-			LocalizationResourceManager.Current.CurrentCulture = new CultureInfo("en");
+			LocalizationResourceManager.Current.Init(AppResources.ResourceManager, new CultureInfo("en"));
 
 			InitializeComponent();
 			MainPage = new BaseNavigationPage(new WelcomePage());

samples/XCT.Sample/Pages/SettingPage.xaml

@@ -4,6 +4,7 @@
                 xmlns:xct="http://xamarin.com/schemas/2020/toolkit"
                 xmlns:pages="clr-namespace:Xamarin.CommunityToolkit.Sample.Pages"
                 xmlns:vm="clr-namespace:Xamarin.CommunityToolkit.Sample.ViewModels"
+                xmlns:resx="clr-namespace:Xamarin.CommunityToolkit.Sample.Resx"
                 x:Class="Xamarin.CommunityToolkit.Sample.Pages.SettingPage"
                 x:DataType="vm:SettingViewModel">
 
@@ -18,13 +19,16 @@
     <StackLayout Padding="{StaticResource ContentPadding}"
                  VerticalOptions="Center"
                  Spacing="10">
+
+        <!--Example of using default ResourceManager-->
         <Label Text="{xct:Translate ChangeLanguage}"/>
 
         <Picker ItemsSource="{Binding SupportedLanguages}"
                 ItemDisplayBinding="{Binding Name}"
                 SelectedItem="{Binding SelectedLanguage}"/>
 
-        <Button Text="{xct:Translate Save}"
+        <!--Example of explicitly passing ResourceManager-->
+        <Button Text="{xct:Translate Save, ResourceManager={x:Static resx:AppResources.ResourceManager}}"
                 Command="{Binding ChangeLanguageCommand, Mode=OneTime}"/>
 
         <Label HorizontalTextAlignment="Center" Text="{Binding AppVersion.Localized}"/>

samples/XCT.Sample/ViewModels/SettingViewModel.cs

@@ -48,8 +48,8 @@ void LoadLanguages()
 		{
 			SupportedLanguages = new List<Language>()
 			{
-				{ new Language(AppResources.English, "en") },
-				{ new Language(AppResources.Spanish, "es") }
+				new Language(AppResources.English, "en"),
+				new Language(AppResources.Spanish, "es")
 			};
 			SelectedLanguage = SupportedLanguages.FirstOrDefault(pro => pro.CI == LocalizationResourceManager.Current.CurrentCulture.TwoLetterISOLanguageName);
 		}

src/CommunityToolkit/Xamarin.CommunityToolkit.UnitTests/Helpers/LocalizationResourceManagerTests/LocalizationResourceManagerTests.cs

@@ -10,54 +10,19 @@ namespace Xamarin.CommunityToolkit.UnitTests.Helpers.LocalizationResourceManager
 	[NonParallelizable]
 	public class LocalizationResourceManagerTests
 	{
-		ResourceManager? resourceManager;
-		CultureInfo? initialCulture;
-		LocalizationResourceManager? localizationManager;
+		readonly ResourceManager resourceManager = new MockResourceManager();
+		readonly CultureInfo initialCulture = CultureInfo.InvariantCulture;
+		readonly LocalizationResourceManager localizationManager = LocalizationResourceManager.Current;
 
 		[SetUp]
 		public void Setup()
 		{
-			resourceManager = new MockResourceManager();
-			initialCulture = CultureInfo.InvariantCulture;
-			localizationManager = LocalizationResourceManager.Current;
-
 			localizationManager.Init(resourceManager, initialCulture);
 		}
 
-		[Test]
-		public void LocalizationResourceManager_GetCulture_Equal_Indexer()
-		{
-			_ = localizationManager ?? throw new NullReferenceException();
-			_ = resourceManager ?? throw new NullReferenceException();
-
-			// Arrange
-			var testString = "test";
-			var culture2 = new CultureInfo("en");
-
-			// Act
-			var responceIndexerCulture1 = localizationManager[testString];
-			var responceGetValueCulture1 = localizationManager.GetValue(testString);
-			var responceResourceManagerCulture1 = resourceManager.GetString(testString, initialCulture);
-
-			localizationManager.CurrentCulture = culture2;
-			var responceIndexerCulture2 = localizationManager[testString];
-			var responceGetValueCulture2 = localizationManager.GetValue(testString);
-			var responceResourceManagerCulture2 = resourceManager.GetString(testString, culture2);
-
-			// Assert
-			Assert.AreEqual(responceResourceManagerCulture1, responceIndexerCulture1);
-			Assert.AreEqual(responceResourceManagerCulture1, responceGetValueCulture1);
-			Assert.AreEqual(responceResourceManagerCulture2, responceIndexerCulture2);
-			Assert.AreEqual(responceResourceManagerCulture2, responceGetValueCulture2);
-		}
-
 		[Test]
 		public void LocalizationResourceManager_PropertyChanged_Triggered()
 		{
-			_ = initialCulture ?? throw new NullReferenceException();
-			_ = resourceManager ?? throw new NullReferenceException();
-			_ = localizationManager ?? throw new NullReferenceException();
-
 			// Arrange
 			var culture2 = new CultureInfo("en");
 			CultureInfo? changedCulture = null;

src/CommunityToolkit/Xamarin.CommunityToolkit.UnitTests/Helpers/LocalizedStringTests/LocalizedStringTests.cs

@@ -10,33 +10,25 @@ namespace Xamarin.CommunityToolkit.UnitTests.Helpers.LocalizedStringTests
 	[NonParallelizable]
 	public class LocalizedStringTests
 	{
-		CultureInfo? initialCulture;
-		ResourceManager? resourceManager;
-		LocalizationResourceManager? localizationManager;
+		readonly ResourceManager resourceManager = new MockResourceManager();
+		readonly CultureInfo initialCulture = CultureInfo.InvariantCulture;
+		readonly LocalizationResourceManager localizationManager = LocalizationResourceManager.Current;
 
 		LocalizedString? localizedString;
 
 		[SetUp]
 		public void Setup()
 		{
-			resourceManager = new MockResourceManager();
-			initialCulture = CultureInfo.InvariantCulture;
-			localizationManager = LocalizationResourceManager.Current;
-
 			localizationManager.Init(resourceManager, initialCulture);
 		}
 
 		[Test]
 		public void LocalizedStringTests_Localized_ValidImplementation()
 		{
-			_ = initialCulture ?? throw new NullReferenceException();
-			_ = resourceManager ?? throw new NullReferenceException();
-			_ = localizationManager ?? throw new NullReferenceException();
-
 			// Arrange
 			var testString = "test";
 			var culture2 = new CultureInfo("en");
-			localizedString = new LocalizedString(localizationManager, () => localizationManager[testString]);
+			localizedString = new LocalizedString(() => resourceManager.GetString(testString, localizationManager.CurrentCulture));
 
 			string? responceOnCultureChanged = null;
 			localizedString.PropertyChanged += (sender, args) => responceOnCultureChanged = localizedString.Localized;
@@ -71,12 +63,10 @@ public void LocalizedStringTests_ImplicitConversion_ValidImplementation()
 		[Test]
 		public void LocalizedStringTests_WeekSubscribe_ValidImplementation()
 		{
-			_ = localizationManager ?? throw new NullReferenceException();
-
 			// Arrange
 			var isTrigered = false;
 			var culture2 = new CultureInfo("en");
-			localizedString = new LocalizedString(localizationManager, () => string.Empty);
+			localizedString = new LocalizedString(() => string.Empty);
 			localizedString.PropertyChanged += (_, __) => isTrigered = true;
 
 			// Act
@@ -93,10 +83,6 @@ public void LocalizedStringTests_WeekSubscribe_ValidImplementation()
 		[Test]
 		public void LocalizedStringTests_Disposed_IfNoReferences()
 		{
-			_ = initialCulture ?? throw new NullReferenceException();
-			_ = resourceManager ?? throw new NullReferenceException();
-			_ = localizationManager ?? throw new NullReferenceException();
-
 			// Arrange
 			var testString = "test";
 			SetLocalizedString();
@@ -111,7 +97,7 @@ public void LocalizedStringTests_Disposed_IfNoReferences()
 
 			void SetLocalizedString()
 			{
-				localizedString = new LocalizedString(localizationManager, () => localizationManager[testString]);
+				localizedString = new LocalizedString(() => resourceManager.GetString(testString, localizationManager.CurrentCulture));
 			}
 		}
 #endif

src/CommunityToolkit/Xamarin.CommunityToolkit/Extensions/TranslateExtension.shared.cs

@@ -1,6 +1,9 @@
 using System;
+using System.Resources;
 using Xamarin.CommunityToolkit.Helpers;
+using Xamarin.CommunityToolkit.ObjectModel;
 using Xamarin.Forms;
+using Xamarin.Forms.Internals;
 using Xamarin.Forms.Xaml;
 
 namespace Xamarin.CommunityToolkit.Extensions
@@ -12,27 +15,48 @@ public class TranslateExtension : IMarkupExtension<BindingBase>
 
 		public string? StringFormat { get; set; }
 
+		public ResourceManager? ResourceManager { get; set; }
+
 		object IMarkupExtension.ProvideValue(IServiceProvider serviceProvider) => ProvideValue(serviceProvider);
 
 		public BindingBase ProvideValue(IServiceProvider serviceProvider)
 		{
 #if NETSTANDARD1_0
 			throw new NotSupportedException("Translate XAML MarkupExtension is not supported on .NET Standard 1.0");
 #else
-			#region Required work-around to prevent linker from removing the implementation
-			if (DateTime.Now.Ticks < 0)
-				_ = LocalizationResourceManager.Current[Text];
-			#endregion
+			ResourceManager ??= LocalizationResourceManager.Current.DefaultResourceManager;
+
+			if (ResourceManager == null)
+			{
+				throw new ArgumentNullException(nameof(ResourceManager), $"Call LocalizationResourceManager.Current.Init(defaultResourceManager) first or provide {nameof(ResourceManager)} argument. Text: {Text}");
+			}
 
 			var binding = new Binding
 			{
 				Mode = BindingMode.OneWay,
 				Path = $"[{Text}]",
-				Source = LocalizationResourceManager.Current,
+				Source = new ObservableResourceManager(ResourceManager),
 				StringFormat = StringFormat
 			};
 			return binding;
 #endif
 		}
+
+#if !NETSTANDARD1_0
+		class ObservableResourceManager : ObservableObject
+		{
+			readonly ResourceManager resourceManager;
+
+			public ObservableResourceManager(ResourceManager resourceManager)
+			{
+				this.resourceManager = resourceManager;
+				LocalizationResourceManager.Current.PropertyChanged += (sender, e) => OnPropertyChanged(null);
+			}
+
+			[Preserve(Conditional = true)]
+			public string? this[string name] =>
+				resourceManager.GetString(name, LocalizationResourceManager.Current.CurrentCulture);
+		}
+#endif
 	}
 }

src/CommunityToolkit/Xamarin.CommunityToolkit/Helpers/LocalizationResourceManager.shared.cs

@@ -14,44 +14,32 @@ public class LocalizationResourceManager : ObservableObject
 
 		public static LocalizationResourceManager Current => currentHolder.Value;
 
-		ResourceManager? resourceManager;
-		CultureInfo currentCulture = Thread.CurrentThread.CurrentUICulture;
+		CultureInfo currentCulture =
+			CultureInfo.DefaultThreadCurrentUICulture ??
+			CultureInfo.DefaultThreadCurrentCulture ??
+			Thread.CurrentThread.CurrentUICulture;
 
 		LocalizationResourceManager()
 		{
 		}
 
-		public void Init(ResourceManager resource) => resourceManager = resource;
+		public void Init(ResourceManager defaultResourceManager) => DefaultResourceManager = defaultResourceManager;
 
-		public void Init(ResourceManager resource, CultureInfo initialCulture)
-		{
-			CurrentCulture = initialCulture;
-			Init(resource);
-		}
+		public void Init(CultureInfo initialCulture) => CurrentCulture = initialCulture;
 
-		public string GetValue(string text)
+		public void Init(ResourceManager defaultResourceManager, CultureInfo initialCulture)
 		{
-			if (resourceManager == null)
-				throw new InvalidOperationException($"Must call {nameof(LocalizationResourceManager)}.{nameof(Init)} first");
-
-			return resourceManager.GetString(text, CurrentCulture) ?? throw new NullReferenceException($"{nameof(text)}: {text} not found");
+			Init(defaultResourceManager);
+			Init(initialCulture);
 		}
 
-		public string this[string text] => GetValue(text);
-
-		[Obsolete("Please, use " + nameof(CurrentCulture) + " to set culture")]
-		[EditorBrowsable(EditorBrowsableState.Never)]
-		public void SetCulture(CultureInfo language) => CurrentCulture = language;
-
 		public CultureInfo CurrentCulture
 		{
 			get => currentCulture;
-			set => SetProperty(ref currentCulture, value, null);
+			set => SetProperty(ref currentCulture, value);
 		}
 
-		[Obsolete("This method is no longer needed with new implementation of " + nameof(LocalizationResourceManager) + ". Please, remove all references to it.")]
-		[EditorBrowsable(EditorBrowsableState.Never)]
-		public void Invalidate() => OnPropertyChanged(null);
+		internal ResourceManager? DefaultResourceManager { get; private set; }
 	}
 #endif
-}
+}

src/CommunityToolkit/Xamarin.CommunityToolkit/Helpers/LocalizedString.shared.cs

@@ -7,27 +7,28 @@ namespace Xamarin.CommunityToolkit.Helpers
 #if !NETSTANDARD1_0
 	public class LocalizedString : ObservableObject
 	{
-		readonly Func<string> generator;
+		readonly Func<string?> generator;
 
-		public LocalizedString(Func<string> generator)
-			: this(LocalizationResourceManager.Current, generator)
-		{
-		}
-
-		public LocalizedString(LocalizationResourceManager localizationManager, Func<string> generator)
+		public LocalizedString(Func<string?> generator)
 		{
 			this.generator = generator;
 
 			// This instance will be unsubscribed and GCed if no one references it
 			// since LocalizationResourceManager uses WeekEventManger
-			localizationManager.PropertyChanged += (sender, e) => OnPropertyChanged(null);
+			LocalizationResourceManager.Current.PropertyChanged += (sender, e) => OnPropertyChanged(nameof(Localized));
+		}
+
+		[Obsolete("Use `LocalizedString(Func<string?> generator)` instead")]
+		public LocalizedString(LocalizationResourceManager localizationManager, Func<string> generator)
+			: this(generator)
+		{
 		}
 
 		[Preserve(Conditional = true)]
-		public string Localized => generator();
+		public string? Localized => generator();
 
 		[Preserve(Conditional = true)]
-		public static implicit operator LocalizedString(Func<string> func) => new LocalizedString(func);
+		public static implicit operator LocalizedString(Func<string?> func) => new LocalizedString(func);
 	}
 #endif
 }

src/CommunityToolkit/Xamarin.CommunityToolkit/ObjectModel/Grouping.shared.cs

@@ -1,7 +1,5 @@
 using System.Collections.Generic;
 
-#nullable enable
-
 namespace Xamarin.CommunityToolkit.ObjectModel
 {
 	/// <summary>

src/CommunityToolkit/Xamarin.CommunityToolkit/ObjectModel/ObservableObject.shared.cs

@@ -4,8 +4,6 @@
 using System.Runtime.CompilerServices;
 using Xamarin.CommunityToolkit.Helpers;
 
-#nullable enable
-
 namespace Xamarin.CommunityToolkit.ObjectModel
 {
 	/// <summary>

src/CommunityToolkit/Xamarin.CommunityToolkit/ObjectModel/ObservableRangeCollection.shared.cs

@@ -4,8 +4,6 @@
 using System.Collections.Specialized;
 using System.ComponentModel;
 
-#nullable enable
-
 namespace Xamarin.CommunityToolkit.ObjectModel
 {
 	/// <summary>