start list box assist for quick unselect

Author: ButchersBoy

MainDemo.Wpf/ProvingGround.xaml

@@ -128,6 +128,7 @@
                 <Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
                 <Setter Property="ScrollViewer.PanningMode" Value="Both"/>
                 <Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
+                <Setter Property="materialDesign:ListBoxAssist.IsQuickUnselectEnabled" Value="True" />
                 <Setter Property="VerticalContentAlignment" Value="Center"/>
                 <Setter Property="ItemContainerStyle" Value="{StaticResource MaterialDesignToggleListBoxItem}"/>
                 <Setter Property="ItemsPanel">

MaterialDesignThemes.Wpf/ListBoxAssist.cs

@@ -0,0 +1,41 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+using System.Windows;
+using System.Windows.Controls;
+using System.Windows.Input;
+using System.Windows.Media;
+
+namespace MaterialDesignThemes.Wpf
+{
+    public static class ListBoxAssist
+    {
+        static ListBoxAssist()
+        {
+            EventManager.RegisterClassHandler(typeof (ListBox), UIElement.PreviewMouseLeftButtonDownEvent,
+                new MouseButtonEventHandler(Target));
+        }
+
+        private static void Target(object sender, MouseButtonEventArgs mouseButtonEventArgs)
+        {
+            Point pt = mouseButtonEventArgs.GetPosition((UIElement)sender);
+            //VisualTreeHelper.HitTest()
+            //mouseButtonEventArgs.
+        }
+
+        public static readonly DependencyProperty IsQuickUnselectEnabledProperty = DependencyProperty.RegisterAttached(
+            "IsQuickUnselectEnabled", typeof(bool), typeof(ListBoxAssist), new FrameworkPropertyMetadata(default(bool)));
+
+        public static void SetIsQuickUnselectEnabled(DependencyObject element, bool value)
+        {
+            element.SetValue(IsQuickUnselectEnabledProperty, value);
+        }
+
+        public static bool GetIsQuickUnselectEnabled(DependencyObject element)
+        {
+            return (bool)element.GetValue(IsQuickUnselectEnabledProperty);
+        }
+    }
+}

MaterialDesignThemes.Wpf/MaterialDesignThemes.Wpf.csproj

@@ -285,6 +285,7 @@
     <Compile Include="HintProxyFabric.cs" />
     <Compile Include="Icon.cs" />
     <Compile Include="IconType.cs" />
+    <Compile Include="ListBoxAssist.cs" />
     <Compile Include="Palette.cs" />
     <Compile Include="Transitions\CircleWipe.cs" />
     <Compile Include="IHintProxy.cs" />