Сделано применение локализации при загрузке окна (#7)

Author: dosymep

src/dosymep.WpfCore/Behaviors/WpfLocalizationBehavior.cs

@@ -11,30 +11,50 @@ namespace dosymep.WpfCore.Behaviors;
 /// Поведение применения языка.
 /// </summary>
 public sealed class WpfLocalizationBehavior : Behavior<FrameworkElement> {
+    private IHasLocalization? _localization;
     private ILocalizationService? _localizationService;
 
     /// <inheritdoc />
     protected override void OnAttached() {
-        Subscribe(AssociatedObject as IHasLocalization);
+        _localization = AssociatedObject as IHasLocalization;
+
+        // Если окно было уже загружено
+        // такое может быть, когда не используется behaviour в конструкторе
+        if(AssociatedObject.IsLoaded) {
+            Subscribe();
+        }
+
+        AssociatedObject.Loaded += AssociatedObjectOnLoaded;
+        AssociatedObject.Unloaded += AssociatedObjectOnUnloaded;
     }
 
     /// <inheritdoc />
     protected override void OnDetaching() {
-        Unsubscribe(AssociatedObject as IHasLocalization);
+        Unsubscribe();
+        AssociatedObject.Loaded -= AssociatedObjectOnLoaded;
+        AssociatedObject.Unloaded -= AssociatedObjectOnUnloaded;
+    }
+
+    private void AssociatedObjectOnLoaded(object sender, RoutedEventArgs e) {
+        Subscribe();
+    }
+
+    private void AssociatedObjectOnUnloaded(object sender, RoutedEventArgs e) {
+        Unsubscribe();
     }
 
-    private void Subscribe(IHasLocalization? localization) {
-        if(localization is not null) {
-            _localizationService = localization.LocalizationService;
-            _localizationService?.SetLocalization(localization.HostLanguage, AssociatedObject);
-            
-            localization.LanguageChanged += LanguageOnThemeChanged;
+    private void Subscribe() {
+        if(_localization is not null) {
+            _localizationService = _localization.LocalizationService;
+            _localizationService?.SetLocalization(_localization.HostLanguage, AssociatedObject);
+
+            _localization.LanguageChanged += LanguageOnThemeChanged;
         }
     }
 
-    private void Unsubscribe(IHasLocalization? localization) {
-        if(localization is not null) {
-            localization.LanguageChanged -= LanguageOnThemeChanged;
+    private void Unsubscribe() {
+        if(_localization is not null) {
+            _localization.LanguageChanged -= LanguageOnThemeChanged;
         }
     }