diff --git a/ModernWpf.Controls/ModernWpf.Controls.csproj b/ModernWpf.Controls/ModernWpf.Controls.csproj
index 79ce1c6c..ba1e10fe 100644
--- a/ModernWpf.Controls/ModernWpf.Controls.csproj
+++ b/ModernWpf.Controls/ModernWpf.Controls.csproj
@@ -19,7 +19,7 @@
 
   <PropertyGroup>
     <PackageId>ModernWpfUI</PackageId>
-    <Version>0.1.191022003</Version>
+    <Version>0.1.191022005</Version>
     <AssemblyVersion>0.1.0.0</AssemblyVersion>
     <FileVersion>0.1.0.0</FileVersion>
     <Authors>Yimeng Wu</Authors>
diff --git a/ModernWpf/ThemeManager.cs b/ModernWpf/ThemeManager.cs
index c1e4bab9..e50a3edd 100644
--- a/ModernWpf/ThemeManager.cs
+++ b/ModernWpf/ThemeManager.cs
@@ -22,6 +22,7 @@ public class ThemeManager : DependencyObject
 
         private static readonly Dictionary<string, ResourceDictionary> _defaultThemeDictionaries = new Dictionary<string, ResourceDictionary>();
 
+        private bool _isInitialized;
         private bool _applicationStarted;
 
         #region ApplicationTheme
@@ -85,18 +86,16 @@ private void OnActualApplicationThemeChanged(DependencyPropertyChangedEventArgs
 
         private void UpdateActualApplicationTheme()
         {
-            if (!ColorsHelper.IsInitialized)
-            {
-                return;
-            }
-
-            if (UsingSystemTheme)
-            {
-                ActualApplicationTheme = GetDefaultAppTheme();
-            }
-            else
+            if (_applicationStarted)
             {
-                ActualApplicationTheme = ApplicationTheme ?? ModernWpf.ApplicationTheme.Light;
+                if (UsingSystemTheme)
+                {
+                    ActualApplicationTheme = GetDefaultAppTheme();
+                }
+                else
+                {
+                    ActualApplicationTheme = ApplicationTheme ?? ModernWpf.ApplicationTheme.Light;
+                }
             }
         }
 
@@ -168,18 +167,16 @@ private void ApplyAccentColor()
 
         private void UpdateActualAccentColor()
         {
-            if (!ColorsHelper.IsInitialized)
-            {
-                return;
-            }
-
-            if (UsingSystemAccentColor)
-            {
-                ActualAccentColor = ColorsHelper.GetSystemAccentColor();
-            }
-            else
+            if (ColorsHelper.IsInitialized)
             {
-                ActualAccentColor = AccentColor ?? ColorsHelper.DefaultAccentColor;
+                if (UsingSystemAccentColor)
+                {
+                    ActualAccentColor = ColorsHelper.GetSystemAccentColor();
+                }
+                else
+                {
+                    ActualAccentColor = AccentColor ?? ColorsHelper.DefaultAccentColor;
+                }
             }
         }
 
@@ -572,11 +569,11 @@ private ThemeManager()
 
         public static ThemeManager Current { get; } = new ThemeManager();
 
-        internal static Uri DefaultLightSource { get; } = GetDefaultSource(LightKey);
+        //internal static Uri DefaultLightSource { get; } = GetDefaultSource(LightKey);
 
-        internal static Uri DefaultDarkSource { get; } = GetDefaultSource(DarkKey);
+        //internal static Uri DefaultDarkSource { get; } = GetDefaultSource(DarkKey);
 
-        internal static Uri DefaultHighContrastSource { get; } = GetDefaultSource(HighContrastKey);
+        //internal static Uri DefaultHighContrastSource { get; } = GetDefaultSource(HighContrastKey);
 
         //internal static ResourceDictionary DefaultLightThemeDictionary => GetDefaultThemeDictionary(LightKey);
 
@@ -588,7 +585,7 @@ private ThemeManager()
 
         internal bool UsingSystemAccentColor => ColorsHelper.SystemColorsSupported && AccentColor == null;
 
-        internal static Uri GetDefaultSource(string theme)
+        private static Uri GetDefaultSource(string theme)
         {
             return PackUriHelper.GetAbsoluteUri($"ThemeResources/{theme}.xaml");
         }
@@ -657,17 +654,12 @@ private static ResourceDictionary FindDictionary(ResourceDictionary parent, Uri
         
         internal void Initialize()
         {
-            Debug.Assert(ThemeResources.Current != null);
-
-            if (ReadLocalValue(ApplicationThemeProperty) == DependencyProperty.UnsetValue)
+            if (_isInitialized)
             {
-                ApplicationTheme = ThemeResources.Current.RequestedTheme;
+                return;
             }
 
-            if (ReadLocalValue(AccentColorProperty) == DependencyProperty.UnsetValue)
-            {
-                AccentColor = ThemeResources.Current.AccentColor;
-            }
+            Debug.Assert(ThemeResources.Current != null);
 
             SystemParameters.StaticPropertyChanged += OnSystemParametersChanged;
 
@@ -675,16 +667,13 @@ internal void Initialize()
             {
                 Application.Current.Startup += OnApplicationStartup;
             }
+
+            _isInitialized = true;
         }
 
         private void OnApplicationStartup(object sender, StartupEventArgs e)
         {
             _applicationStarted = true;
-            InitializeThemeResources();
-        }
-
-        private void InitializeThemeResources()
-        {
             ColorsHelper.BackgroundColorChanged += OnSystemBackgroundColorChanged;
             ColorsHelper.AccentColorChanged += OnSystemAccentColorChanged;
             ColorsHelper.Initialize();
diff --git a/ModernWpf/ThemeResources.cs b/ModernWpf/ThemeResources.cs
index b1d45e4e..13869df2 100644
--- a/ModernWpf/ThemeResources.cs
+++ b/ModernWpf/ThemeResources.cs
@@ -37,7 +37,6 @@ internal static ThemeResources Current
             }
         }
 
-        private ApplicationTheme? _requestedTheme;
         /// <summary>
         /// Gets or sets a value that determines the light-dark preference for the overall
         /// theme of an app.
@@ -48,31 +47,34 @@ internal static ThemeResources Current
         /// </returns>
         public ApplicationTheme? RequestedTheme
         {
-            get => _requestedTheme;
+            get => ThemeManager.Current.ApplicationTheme;
             set
             {
-                if (_requestedTheme != value)
+                if (ThemeManager.Current.ApplicationTheme != value)
                 {
-                    _requestedTheme = value;
-                    OnThemePropertyChanged();
+                    ThemeManager.Current.SetCurrentValue(ThemeManager.ApplicationThemeProperty, value);
+
+                    if (!IsInitializePending && DesignMode.DesignModeEnabled)
+                    {
+                        UpdateDesignTimeThemeDictionary();
+                    }
                 }
             }
         }
 
-        private Color? _accentColor;
         /// <summary>
         /// Gets or sets the accent color of the app.
         /// </summary>
         public Color? AccentColor
         {
-            get => _accentColor;
+            get => ThemeManager.Current.AccentColor;
             set
             {
-                if (_accentColor != value)
+                if (ThemeManager.Current.AccentColor != value)
                 {
-                    _accentColor = value;
+                    ThemeManager.Current.SetCurrentValue(ThemeManager.AccentColorProperty, value);
 
-                    if (!IsInitializePending)
+                    if (!IsInitializePending && DesignMode.DesignModeEnabled)
                     {
                         UpdateDesignTimeSystemColors();
                     }
@@ -95,6 +97,7 @@ public Color? AccentColor
 
         private void DesignTimeInit()
         {
+            Debug.Assert(DesignMode.DesignModeEnabled);
             UpdateDesignTimeSystemColors();
             UpdateDesignTimeThemeDictionary();
             SystemParameters.StaticPropertyChanged += OnSystemParametersPropertyChanged;
@@ -102,35 +105,27 @@ private void DesignTimeInit()
 
         private void UpdateDesignTimeSystemColors()
         {
-            if (DesignMode.DesignModeEnabled)
+            Debug.Assert(DesignMode.DesignModeEnabled);
+            var rd = GetDesignTimeSystemColors();
+            if (MergedDictionaries.Count == 0)
             {
-                var rd = GetDesignTimeSystemColors();
-                if (MergedDictionaries.Count == 0)
-                {
-                    MergedDictionaries.Add(rd);
-                }
-                else
-                {
-                    MergedDictionaries[0] = rd;
-                }
+                MergedDictionaries.Add(rd);
             }
-        }
-
-        private void OnThemePropertyChanged()
-        {
-            if (!IsInitializePending && DesignMode.DesignModeEnabled)
+            else
             {
-                UpdateDesignTimeThemeDictionary();
+                MergedDictionaries[0] = rd;
             }
         }
 
         private void UpdateDesignTimeThemeDictionary()
         {
+            Debug.Assert(DesignMode.DesignModeEnabled);
             ApplyApplicationTheme(RequestedTheme ?? ApplicationTheme.Light);
         }
 
         private ResourceDictionary GetDesignTimeSystemColors()
         {
+            Debug.Assert(DesignMode.DesignModeEnabled);
             if (AccentColor.HasValue)
             {
                 return new ColorPaletteResources { Accent = AccentColor };