Added DropDownItem.

So that drop down items can be highlighted as they're hovered.

samples/ControlCatalog/Pages/CarouselPage.paml

@@ -23,9 +23,9 @@
     <StackPanel Orientation="Horizontal" Gap="4">
       <TextBlock VerticalAlignment="Center">Transition</TextBlock>
       <DropDown Name="transition" SelectedIndex="1" VerticalAlignment="Center">
-        <ListBoxItem>None</ListBoxItem>
-        <ListBoxItem>Slide</ListBoxItem>
-        <ListBoxItem>Crossfade</ListBoxItem>
+        <DropDownItem>None</DropDownItem>
+        <DropDownItem>Slide</DropDownItem>
+        <DropDownItem>Crossfade</DropDownItem>
       </DropDown>
     </StackPanel>
     

src/Perspex.Controls/DropDown.cs

@@ -80,7 +80,7 @@ namespace Perspex.Controls
 
         protected override IItemContainerGenerator CreateItemContainerGenerator()
         {
-            return new ItemContainerGenerator<ListBoxItem>(this, ListBoxItem.ContentProperty);
+            return new ItemContainerGenerator<DropDownItem>(this, DropDownItem.ContentProperty);
         }
 
         protected override void OnAttachedToLogicalTree(LogicalTreeAttachmentEventArgs e)

src/Perspex.Controls/DropDownItem.cs

@@ -0,0 +1,12 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+namespace Perspex.Controls
+{
+    /// <summary>
+    /// A selectable item in a <see cref="DropDown"/>.
+    /// </summary>
+    public class DropDownItem : ListBoxItem
+    {
+    }
+}

src/Perspex.Controls/Perspex.Controls.csproj

@@ -50,6 +50,7 @@
     <Compile Include="HotkeyManager.cs" />
     <Compile Include="INameScope.cs" />
     <Compile Include="IPseudoClasses.cs" />
+    <Compile Include="DropDownItem.cs" />
     <Compile Include="Mixins\ContentControlMixin.cs" />
     <Compile Include="NameScope.cs" />
     <Compile Include="NameScopeEventArgs.cs" />

src/Perspex.Controls/Primitives/SelectingItemsControl.cs

@@ -245,8 +245,8 @@ namespace Perspex.Controls.Primitives
         protected IControl GetContainerFromEventSource(IInteractive eventSource)
         {
             var item = ((IVisual)eventSource).GetSelfAndVisualAncestors()
-                .OfType<ILogical>()
-                .FirstOrDefault(x => x.LogicalParent == this);
+                .OfType<IControl>()
+                .FirstOrDefault(x => x.LogicalParent == this && ItemContainerGenerator?.IndexFromContainer(x) != -1);
 
             return item as IControl;
         }

src/Perspex.Themes.Default/DefaultTheme.paml

@@ -5,6 +5,7 @@
   <StyleInclude Source="resm:Perspex.Themes.Default.CheckBox.paml?assembly=Perspex.Themes.Default"/>
   <StyleInclude Source="resm:Perspex.Themes.Default.ContentControl.paml?assembly=Perspex.Themes.Default"/>
   <StyleInclude Source="resm:Perspex.Themes.Default.DropDown.paml?assembly=Perspex.Themes.Default"/>
+  <StyleInclude Source="resm:Perspex.Themes.Default.DropDownItem.paml?assembly=Perspex.Themes.Default"/>
   <StyleInclude Source="resm:Perspex.Themes.Default.GridSplitter.paml?assembly=Perspex.Themes.Default"/>
   <StyleInclude Source="resm:Perspex.Themes.Default.ItemsControl.paml?assembly=Perspex.Themes.Default"/>
   <StyleInclude Source="resm:Perspex.Themes.Default.ListBox.paml?assembly=Perspex.Themes.Default"/>

src/Perspex.Themes.Default/DropDown.paml

@@ -35,8 +35,7 @@
                    PlacementTarget="{TemplateBinding}"
                    StaysOpen="False">
               <Border BorderBrush="Black"
-                      BorderThickness="1"
-                      Padding="4">
+                      BorderThickness="1">
                 <ItemsPresenter Name="PART_ItemsPresenter"
                                 Items="{TemplateBinding Items}" 
                                 MemberSelector="{TemplateBinding MemberSelector}"/>
@@ -46,7 +45,6 @@
         </Border>
       </ControlTemplate>
     </Setter>
-
   </Style>
   <Style Selector="CheckBox /template/ Path#checkMark">
     <Setter Property="IsVisible" Value="False"/>

src/Perspex.Themes.Default/DropDownItem.paml

@@ -0,0 +1,23 @@
+<Styles xmlns="https://github.com/perspex">
+  <Style Selector="DropDownItem">
+    <Setter Property="Padding" Value="2"/>
+    <Setter Property="Template">
+      <ControlTemplate>
+        <Border Name="border"
+                Background="{TemplateBinding Background}"
+                BorderBrush="{TemplateBinding BorderBrush}"
+                BorderThickness="{TemplateBinding BorderThickness}">
+          <ContentPresenter Name="PART_ContentPresenter"
+                            Content="{TemplateBinding Content}"
+                            Margin="{TemplateBinding Padding}"/>
+        </Border>
+      </ControlTemplate>
+    </Setter>
+  </Style>
+  <Style Selector="DropDownItem:selected /template/ Border#border">
+    <Setter Property="Background" Value="#ffe5f0fc"/>
+  </Style>
+  <Style Selector="DropDownItem:pointerover /template/ Border#border">
+    <Setter Property="Background" Value="#ffd0d0d0"/>
+  </Style>
+</Styles>

src/Perspex.Themes.Default/Perspex.Themes.Default.csproj

@@ -144,6 +144,9 @@
       <SubType>Designer</SubType>
     </EmbeddedResource>
     <EmbeddedResource Include="Expander.paml" />
+    <EmbeddedResource Include="DropDownItem.paml">
+      <SubType>Designer</SubType>
+    </EmbeddedResource>
     <None Include="packages.config" />
     <EmbeddedResource Include="PopupRoot.paml">
       <SubType>Designer</SubType>