Fixed clipping when an unloaded Marquee's size changes

Author: Avid29

components/Marquee/src/Marquee.Events.cs

@@ -56,6 +56,10 @@ private void Marquee_Loaded(object sender, RoutedEventArgs e)
             _marqueeStoryboard.Completed += StoryBoard_Completed;
         }
 
+        // The size may have channged while unloaded.
+        // Clip the marquee
+        ClipMarquee();
+
         // Setup the animation
         UpdateMarquee(false);
 
@@ -93,11 +97,8 @@ private void Container_SizeChanged(object sender, SizeChangedEventArgs e)
         if (_marqueeContainer is null)
             return;
 
-        // Clip the marquee within its bounds
-        _marqueeContainer.Clip = new RectangleGeometry
-        {
-            Rect = new Rect(0, 0, e.NewSize.Width, e.NewSize.Height)
-        };
+        // Clip the marquee
+        ClipMarquee(e.NewSize.Width, e.NewSize.Height);
 
         // Update animation on the fly
         UpdateMarquee(true);

components/Marquee/src/Marquee.cs

@@ -456,4 +456,19 @@ private Storyboard CreateMarqueeStoryboardAnimation(double start, double end, Ti
 
         return marqueeStoryboard;
     }
+
+    private void ClipMarquee(double width = default, double height = default)
+    {
+        if (_marqueeContainer is null)
+            return;
+
+        width = width is default(double) ? _marqueeContainer.ActualWidth : width;
+        height = height is default(double) ? _marqueeContainer.ActualHeight : height;
+
+        // Clip the marquee within the bounds of the container
+        _marqueeContainer.Clip = new RectangleGeometry
+        {
+            Rect = new Rect(0, 0, width, height)
+        };
+    }
 }