From 05b729edf848203aecac9514a26cf05727e2f5c0 Mon Sep 17 00:00:00 2001
From: Ben Wallis <atomyc+github@gmail.com>
Date: Mon, 3 Dec 2018 16:28:22 +0000
Subject: [PATCH] Fixed ScrollViewer in ItemFilterBlockView handling mouse
 wheel events (#105)

---
 Filtration/Views/ItemFilterBlockView.xaml    |  4 ++--
 Filtration/Views/ItemFilterBlockView.xaml.cs | 20 ++++++++++++++++++--
 2 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/Filtration/Views/ItemFilterBlockView.xaml b/Filtration/Views/ItemFilterBlockView.xaml
index f771ccc..02cadb6 100644
--- a/Filtration/Views/ItemFilterBlockView.xaml
+++ b/Filtration/Views/ItemFilterBlockView.xaml
@@ -277,7 +277,7 @@
                                         </CollectionViewSource.SortDescriptions>
                                     </CollectionViewSource>
                                 </Grid.Resources>
-                                <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled">
+                                <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled" PreviewMouseWheel="UIElement_OnPreviewMouseWheel">
                                     <ItemsControl ItemsSource="{Binding Source={StaticResource BlockItemsCollectionViewSource}}"
                                               ItemContainerStyle="{StaticResource BlockItemFadeInStyle}">
                                         <ItemsControl.ItemsPanel>
@@ -338,7 +338,7 @@
                                         </CollectionViewSource.SortDescriptions>
                                     </CollectionViewSource>
                                 </Grid.Resources>
-                                <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled">
+                                <ScrollViewer HorizontalScrollBarVisibility="Auto" VerticalScrollBarVisibility="Disabled" PreviewMouseWheel="UIElement_OnPreviewMouseWheel">
                                     <ItemsControl ItemsSource="{Binding Source={StaticResource BlockItemsCollectionViewSource}}"
                                               ItemContainerStyle="{StaticResource BlockItemFadeInStyle}">
                                         <ItemsControl.ItemsPanel>
diff --git a/Filtration/Views/ItemFilterBlockView.xaml.cs b/Filtration/Views/ItemFilterBlockView.xaml.cs
index 85c27d1..e02df92 100644
--- a/Filtration/Views/ItemFilterBlockView.xaml.cs
+++ b/Filtration/Views/ItemFilterBlockView.xaml.cs
@@ -1,4 +1,6 @@
-using System.Windows.Input;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
 using System.Windows.Media;
 
 namespace Filtration.Views
@@ -25,10 +27,24 @@ namespace Filtration.Views
         {
             if (e.Key == Key.Enter)
             {
-                System.Windows.Controls.AutoCompleteBox box = sender as System.Windows.Controls.AutoCompleteBox;
+                AutoCompleteBox box = sender as AutoCompleteBox;
                 dynamic viewModel = box.DataContext;
                 viewModel.AddBlockGroupCommand.Execute(null);
             }
         }
+        
+        private void UIElement_OnPreviewMouseWheel(object sender, MouseWheelEventArgs e)
+        {
+            if (sender is ScrollViewer viewer && !e.Handled)
+            {
+                e.Handled = true;
+
+                var eventArg = new MouseWheelEventArgs(e.MouseDevice, e.Timestamp, e.Delta) {RoutedEvent = MouseWheelEvent, Source = viewer};
+                if (viewer.Parent is UIElement parent)
+                {
+                    parent.RaiseEvent(eventArg);
+                }
+            }
+        }
     }
 }