Abstraction and doc fix

Author: niels9001

components/Shimmer/samples/Shimmer.md

@@ -12,6 +12,6 @@ issue-id: 390
 ---
 # Shimmer
 
-The Shimmer control can be used to communicate to the user a certain UI element is fetching data or is loading. The `Duration` can be set to change the time in between fades.
+The Shimmer control can be used to communicate to the user a certain UI element is fetching data or is loading. `Duration` can be set to set the length of the animation.
 
 > [!SAMPLE ShimmerSample]

components/Shimmer/src/Shimmer/Shimmer.Properties.cs

@@ -10,34 +10,20 @@ public partial class Shimmer : Control
     /// Identifies the <see cref="Duration"/> dependency property.
     /// </summary>
     public static readonly DependencyProperty DurationProperty = DependencyProperty.Register(
-        nameof(Duration), typeof(TimeSpan), typeof(Shimmer), new PropertyMetadata(TimeSpan.FromMilliseconds(1600), (s, e) =>
-        {
-            var self = (Shimmer)s;
-            if (self.IsActive)
-            {
-                self.TryStartAnimation();
-            }
-        }));
+       nameof(Duration),
+       typeof(object),
+       typeof(Shimmer),
+       new PropertyMetadata(defaultValue: TimeSpan.FromMilliseconds(1600), PropertyChanged));
 
     /// <summary>
     /// Identifies the <see cref="IsActive"/> dependency property.
     /// </summary>
     public static readonly DependencyProperty IsActiveProperty = DependencyProperty.Register(
-        nameof(IsActive), typeof(bool), typeof(Shimmer), new PropertyMetadata(true, (s, e) =>
-        {
-            var self = (Shimmer)s;
-            var isActive = (bool)e.NewValue;
+      nameof(IsActive),
+      typeof(bool),
+      typeof(Shimmer),
+      new PropertyMetadata(defaultValue: true, PropertyChanged));
 
-            if (isActive)
-            {
-                self.StopAnimation();
-                self.TryStartAnimation();
-            }
-            else
-            {
-                self.StopAnimation();
-            }
-        }));
 
     /// <summary>
     /// Gets or sets the animation duration
@@ -56,4 +42,18 @@ public bool IsActive
         get => (bool)GetValue(IsActiveProperty);
         set => SetValue(IsActiveProperty, value);
     }
+
+    private static void PropertyChanged(DependencyObject s, DependencyPropertyChangedEventArgs e)
+    {
+        var self = (Shimmer)s;
+        if (self.IsActive)
+        {
+            self.StopAnimation();
+            self.TryStartAnimation();
+        }
+        else
+        {
+            self.StopAnimation();
+        }
+    }
 }

components/Shimmer/src/Shimmer/Shimmer.cs

@@ -84,7 +84,6 @@ private void OnUnloaded(object sender, RoutedEventArgs e)
         {
             ElementCompositionPreview.SetElementChildVisual(_shape, null);
 
-            
             _rectangleGeometry!.Dispose();
             _shapeVisual!.Dispose();
             _shimmerMaskGradient!.Dispose();