source: branches/2893_BNLR/HeuristicLab.ExtLibs/HeuristicLab.AvalonEdit/5.0.1/AvalonEdit-5.0.1/Search/DropDownButton.xaml

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  xmlns:local="clr-namespace:ICSharpCode.AvalonEdit.Search"
>
  <!-- Colors for DropDownButton and SplitButton -->
  <SolidColorBrush x:Key="{ComponentResourceKey {x:Type local:DropDownButton}, ActiveBorder}" Color="#FF0A246A"/>
  <SolidColorBrush x:Key="{ComponentResourceKey {x:Type local:DropDownButton}, ActiveBackground}" Color="#FFB6BDD2"/>
  
  <!-- Style and Template for DropDownButton -->
  <Style TargetType="{x:Type local:DropDownButton}">
    <Setter Property="TextElement.Foreground" Value = "{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" />
    <Setter Property="Control.Padding" Value="2,2,2,2"/>
    <Setter Property="Border.BorderThickness" Value="1,1,1,1"/>
    <Setter Property="Panel.Background" Value="Transparent"/>
    <Setter Property="Border.BorderBrush" Value="Transparent"/>
    <Setter Property="FrameworkElement.HorizontalAlignment" Value="Center"/>
    <Setter Property="FrameworkElement.VerticalAlignment" Value="Center"/>
    <Setter Property="Control.HorizontalContentAlignment" Value="Center"/>
    <Setter Property="Control.VerticalContentAlignment" Value="Center"/>
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="local:DropDownButton"
                         xmlns:s="clr-namespace:System;assembly=mscorlib">
          <Border
            BorderThickness="{TemplateBinding Border.BorderThickness}"
            BorderBrush="{TemplateBinding Border.BorderBrush}"
            Background="{TemplateBinding Panel.Background}"
            Name="OuterBorder"
            SnapsToDevicePixels="True"
          >
            <StackPanel Orientation="Horizontal">
              <ContentPresenter
                Margin="{TemplateBinding Control.Padding}"
                Content="{TemplateBinding ContentControl.Content}"
                ContentTemplate="{TemplateBinding ContentControl.ContentTemplate}"
                ContentStringFormat="{TemplateBinding ContentControl.ContentStringFormat}"
                HorizontalAlignment="{TemplateBinding Control.HorizontalContentAlignment}"
                VerticalAlignment="{TemplateBinding Control.VerticalContentAlignment}"
                SnapsToDevicePixels="{TemplateBinding UIElement.SnapsToDevicePixels}" />
              <Path Margin="0,2,2,2"
                    Data = "M0,0 L1,0 0.5,1 z"
                    Fill = "{TemplateBinding TextElement.Foreground}"
                    Width = "7"
                    Height = "3.5"
                    Stretch = "Fill"/>
            </StackPanel>
          </Border>
          <ControlTemplate.Triggers>
            <Trigger Property="UIElement.IsMouseOver" Value="True">
              <Setter Property="Border.BorderBrush" TargetName="OuterBorder" Value="{DynamicResource {ComponentResourceKey {x:Type local:DropDownButton}, ActiveBorder}}" />
              <Setter Property="Panel.Background" TargetName="OuterBorder" Value="{DynamicResource {ComponentResourceKey {x:Type local:DropDownButton}, ActiveBackground}}"/>
            </Trigger>
            <Trigger Property="UIElement.IsKeyboardFocused" Value="True">
              <Setter Property="Border.BorderBrush" TargetName="OuterBorder" Value="{DynamicResource {ComponentResourceKey {x:Type local:DropDownButton}, ActiveBorder}}"/>
              <Setter Property="Panel.Background" TargetName="OuterBorder" Value="{DynamicResource {ComponentResourceKey {x:Type local:DropDownButton}, ActiveBackground}}"/>
            </Trigger>
            <Trigger Property="UIElement.IsEnabled" Value="False">
              <Setter Property="TextElement.Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
            </Trigger>
            <Trigger Property="local:DropDownButton.IsDropDownContentOpen" Value="True">
              <Setter Property="Border.BorderBrush" TargetName="OuterBorder" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}" />
              <Setter Property="Border.BorderThickness" TargetName="OuterBorder" Value="1,1,1,0" />
              <Setter Property="Border.Padding" TargetName="OuterBorder" Value="0,0,0,1" />
              <Setter Property="Panel.Background" TargetName="OuterBorder" Value="Transparent"/>
            </Trigger>
          </ControlTemplate.Triggers>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>
</ResourceDictionary>