[ToDo] fix: Wrong value for default theme & Opening Settings Flyout Changes App

reference/ToDo/src/ToDo/Presentation/SettingsViewModel.cs

@@ -10,8 +10,8 @@ public partial class SettingsViewModel
     private readonly INavigator _sourceNavigator;
     private readonly INavigator _navigator;
     private readonly IThemeService _themeService;
-
     private bool _isDark;
+    private readonly IDispatcher _dispatcher;
 
     public ILocalizationService LocalizationSettings { get; }
 
@@ -36,12 +36,11 @@ public SettingsViewModel(
         _userSvc = userSvc;
         LocalizationSettings = localizationSettings;
         _themeService = themeService;
+        _dispatcher = dispatcher;
 
         AppThemes = new string[] { localizer["SettingsFlyout_ThemeLight"], localizer["SettingsFlyout_ThemeDark"] };
-
-        _ = dispatcher.TryEnqueue(() => {
-            _isDark = _themeService.IsDark;
-        });
+
+        _ = dispatcher.TryEnqueue(() => { _isDark = _themeService.IsDark; });
 
         Cultures = localizationConfiguration.Value!.Cultures!.Select(c => new DisplayCulture(localizer[$"SettingsFlyout_LanguageLabel_{c}"], c)).ToArray();
         SelectedCulture = State.Value(this, () => Cultures.FirstOrDefault(c => c.Culture == LocalizationSettings.CurrentCulture.ToString()) ?? Cultures.First());
@@ -56,9 +55,13 @@ public SettingsViewModel(
 
     [Value]
     public IState<DisplayCulture> SelectedCulture { get; }
-
+    
     [Value]
-    public IState<string> SelectedAppTheme => State.Value(this, () => AppThemes[_isDark ? 1 : 0]);
+    public IState<string> SelectedAppTheme => State.Async(this, async ct =>
+    {
+        var isDark = await _dispatcher.ExecuteAsync(async _ => await Task.FromResult(_themeService.IsDark), ct);
+        return AppThemes[isDark ? 1 : 0];
+    });
 
     public async ValueTask SignOut(CancellationToken ct)
     {
@@ -70,11 +73,10 @@ public async ValueTask SignOut(CancellationToken ct)
             await _sourceNavigator.NavigateViewModelAsync<HomeViewModel>(this);
         }
     }
-
-    public async ValueTask ChangeAppTheme(CancellationToken ct)
+    
+    public async ValueTask ChangeAppTheme(string selectedTheme, CancellationToken ct)
     {
-        var currentTheme = _themeService.Theme;
-        var newTheme = currentTheme == AppTheme.Dark ? AppTheme.Light : AppTheme.Dark;
+        var newTheme = selectedTheme == AppThemes[1] ? AppTheme.Dark : AppTheme.Light;
         await _themeService.SetThemeAsync(newTheme);
         WeakReferenceMessenger.Default.Send(new ThemeChangedMessage(newTheme));
     }

reference/ToDo/src/ToDo/Views/Dialogs/SettingsFlyout.xaml

@@ -103,7 +103,7 @@
               <utu:ChipGroup x:Name="ThemeChipGroup"
                              SelectionMode="Single"
                              ItemsSource="{Binding AppThemes}"
-                             SelectedItem="{Binding SelectedAppTheme, Mode=TwoWay}"
+                             SelectedItem="{Binding SelectedAppTheme}"
                              ItemChecked="ThemeChipGroup_ItemChecked"
                              Style="{StaticResource FilterChipGroupStyle}">
                 <utu:ChipGroup.ItemTemplate>

reference/ToDo/src/ToDo/Views/Dialogs/SettingsFlyout.xaml.cs

@@ -23,11 +23,11 @@ private void ThemeChipGroup_ItemChecked(object sender, ChipItemEventArgs e)
 #if ANDROID
             if (_isThemeInitialized)
             {
-                viewModel.ChangeAppTheme.Execute(null);
+                viewModel.ChangeAppTheme.Execute(e.Item);
             }
             _isThemeInitialized = true;
 #else
-            viewModel.ChangeAppTheme.Execute(null);
+            viewModel.ChangeAppTheme.Execute(e.Item);
 #endif
         }
     }