优化

Sample/HybridThemeManager.cs

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+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Media;
+using System.Windows.Media.Animation;
+
+namespace Sample
+{
+    public enum ThemeMode { Light, Dark }
+
+    /// <summary>
+    /// 一个优雅且绝对可靠的主题管理器。
+    /// 它通过一个明确的资源键列表，精确地对指定画刷进行平滑的过渡动画。
+    /// </summary>
+    public static class HybridThemeManager
+    {
+        // 【契约】我们回归到使用一个明确的、硬编码的列表。
+        // 这是最可靠的方式，它清晰地定义了哪些资源参与动画。
+        private static readonly List<string> AnimatableBrushKeys = new List<string>
+        {
+            //"AppBackgroundBrush",
+            //"AppTextBrush"
+        };
+        static HybridThemeManager()
+        {
+            var appResources = Application.Current.Resources;
+            foreach (var dict in appResources.MergedDictionaries)
+            {
+                var keys = dict.Keys;
+                //AnimatableBrushKeys.Clear();
+                AnimatableBrushKeys.AddRange(
+                    keys.OfType<string>()
+                        .Where(key => key.EndsWith("Brush") && dict[key] is SolidColorBrush)
+                );
+            }
+            //foreach (ResourceDictionary dict in appResources)
+            //{
+               
+            //}
+        }
+        private static ThemeMode _currentMode = ThemeMode.Light;
+        private static bool _isSwitching = false;
+
+        public static async Task SwitchThemeAsync()
+        {
+            if (_isSwitching) return;
+
+            _isSwitching = true;
+            try
+            {
+                var targetMode = _currentMode == ThemeMode.Light ? ThemeMode.Dark : ThemeMode.Light;
+                var appResources = Application.Current.Resources;
+
+                // 步骤 1: “快照” - 根据【明确的列表】，记录当前颜色
+                var fromColors = TakeColorSnapshot(appResources);
+
+                // 步骤 2: “交换” - 替换资源字典
+                SwapThemeDictionary(appResources, targetMode);
+
+                // 步骤 3: “动画” - 对【明确的列表】中的画刷启动动画
+                await AnimateToNewTheme(appResources, fromColors);
+
+                _currentMode = targetMode;
+            }
+            finally
+            {
+                _isSwitching = false;
+            }
+        }
+
+        private static Dictionary<string, Color> TakeColorSnapshot(ResourceDictionary resources)
+        {
+            return AnimatableBrushKeys
+                .Where(key => resources.Contains(key) && resources[key] is SolidColorBrush)
+                .ToDictionary(key => key, key => ((SolidColorBrush)resources[key]).Color);
+        }
+
+        private static void SwapThemeDictionary(ResourceDictionary resources, ThemeMode targetMode)
+        {
+            var newThemeUri = new Uri($"/Themes/{targetMode}.xaml", UriKind.Relative);
+            var newThemeDict = new ResourceDictionary { Source = newThemeUri };
+
+            var oldDict = resources.MergedDictionaries.FirstOrDefault(d => d.Source?.OriginalString.Contains("/Themes/") ?? false);
+            if (oldDict != null)
+            {
+                resources.MergedDictionaries.Remove(oldDict);
+            }
+            resources.MergedDictionaries.Add(newThemeDict);
+        }
+
+        private static Task AnimateToNewTheme(ResourceDictionary resources, IReadOnlyDictionary<string, Color> fromColors)
+        {
+            var animationTasks = new List<Task>();
+            foreach (var key in AnimatableBrushKeys)
+            {
+                if (resources.Contains(key) && resources[key] is SolidColorBrush newBrush && fromColors.TryGetValue(key, out var fromColor))
+                {
+                    // 【健壮性】依然保留对 StaticResource (冻结) 的处理
+                    if (newBrush.IsFrozen)
+                    {
+                        newBrush = newBrush.Clone();
+                        resources[key] = newBrush;
+                    }
+
+                    var toColor = newBrush.Color;
+                    newBrush.Color = fromColor; // 伪装
+
+                    animationTasks.Add(AnimateBrushColorAsync(newBrush, toColor));
+                }
+            }
+            return Task.WhenAll(animationTasks);
+        }
+
+        private static Task AnimateBrushColorAsync(SolidColorBrush brush, Color toColor)
+        {
+            var tcs = new TaskCompletionSource<bool>();
+            var animation = new ColorAnimation
+            {
+                From = brush.Color,
+                To = toColor,
+                Duration = TimeSpan.FromMilliseconds(400),
+                EasingFunction = new CubicEase { EasingMode = EasingMode.EaseOut }
+            };
+
+            animation.Completed += (s, e) =>
+            {
+                brush.BeginAnimation(SolidColorBrush.ColorProperty, null);
+                brush.Color = toColor;
+                tcs.TrySetResult(true);
+            };
+            brush.BeginAnimation(SolidColorBrush.ColorProperty, animation);
+            return tcs.Task;
+        }
+    }
+}