Common.Wpf/Toolbar/DropDownButton/DropDownButtonStyle.xaml

<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
                    xmlns:themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Luna"
                    xmlns:DropDownButton="clr-namespace:Common.Wpf.Toolbar.DropDownButton">

  <!-- Used for Checkmark, Radio button, TreeViewItem, Expander ToggleButton glyphs -->
  <SolidColorBrush x:Key="GlyphBrush" Color="#444"/>

  <!-- SelectedBackgroundBrush is used for the Selected item in ListBoxItem, ComboBoxItem-->
  <SolidColorBrush x:Key="SelectedBackgroundBrush" Color="#DDD"/>

  <!-- Disabled Brushes are used for the Disabled look of each control -->
  <SolidColorBrush x:Key="DisabledForegroundBrush" Color="#888"/>

  <!-- NormalBrush is used as the Background for SimpleButton, SimpleRepeatButton -->
  <LinearGradientBrush x:Key="NormalBrush" EndPoint="0,1" StartPoint="0,0">
    <GradientStop Color="#EEE" Offset="0.0"/>
    <GradientStop Color="#CCC" Offset="1.0"/>
  </LinearGradientBrush>
  <LinearGradientBrush x:Key="NormalBorderBrush" EndPoint="0,1" StartPoint="0,0">
    <GradientStop Color="#CCC" Offset="0.0"/>
    <GradientStop Color="#444" Offset="1.0"/>
  </LinearGradientBrush>

  <Style x:Key="ButtonFocusVisual">
    <Setter Property="Control.Template">
      <Setter.Value>
        <ControlTemplate>
          <Rectangle SnapsToDevicePixels="true" Margin="3" Stroke="Black" StrokeDashArray="1 2" StrokeThickness="1"/>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>

  <LinearGradientBrush x:Key="ButtonNormalBackgroundFill" EndPoint="0.5,1" StartPoint="0.5,0">
    <GradientStop Color="#FFFFFFFF" Offset="0"/>
    <GradientStop Color="#FFF0F0EA" Offset="0.9"/>
  </LinearGradientBrush>

  <SolidColorBrush x:Key="ButtonBorder" Color="#FF003C74"/>

  <Style x:Key="LabelStyle" TargetType="{x:Type Label}" BasedOn="{x:Null}">
    <Setter Property="HorizontalAlignment" Value="Stretch" />
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="{x:Type Label}">
          <Grid>
            <ContentPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" RecognizesAccessKey="True"/>
          </Grid>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>

  <Style TargetType="{x:Type DropDownButton:DropDownButton}">
    <Setter Property="FocusVisualStyle" Value="{StaticResource ButtonFocusVisual}"/>
    <Setter Property="Background" Value="{StaticResource ButtonNormalBackgroundFill}"/>
    <Setter Property="BorderBrush" Value="{StaticResource ButtonBorder}"/>
    <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
    <Setter Property="HorizontalAlignment" Value="Center"/>
    <Setter Property="VerticalAlignment" Value="Center"/>
    <Setter Property="MinHeight" Value="22" />
    <Setter Property="MinWidth" Value="80" />
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="{x:Type DropDownButton:DropDownButton}">
          <themes:ButtonChrome x:Name="Chrome" SnapsToDevicePixels="True" BorderBrush="{TemplateBinding BorderBrush}" Fill="{TemplateBinding Background}" RenderMouseOver="{TemplateBinding IsMouseOver}" RenderPressed="{TemplateBinding IsPressed}" ThemeColor="NormalColor">
            <Label Style="{StaticResource LabelStyle}">
              <Grid>
                <Grid.ColumnDefinitions>
                  <ColumnDefinition Width="Auto"/>
                  <ColumnDefinition Width="*"/>
                  <ColumnDefinition Width="Auto"/>
                </Grid.ColumnDefinitions>
                <Image x:Name="icon" Grid.Column="0" Margin="4,0,2,0" VerticalAlignment="Center" Width="16" Height="16" Source="{TemplateBinding Image}" />
                <Label Grid.Column="1" Content="{TemplateBinding Text}" Target="{TemplateBinding Target}" HorizontalAlignment="Center" VerticalAlignment="Center" Padding="0" Margin="0,0,3,0" Foreground="{TemplateBinding Foreground}"/>
                <Path Grid.Column="2" Fill="{DynamicResource GlyphBrush}" Data="M 0 0 L 4 4 L 8 0 Z"  Height="5" Margin="3,2,2,0"/>
              </Grid>
            </Label>
          </themes:ButtonChrome>
          <ControlTemplate.Triggers>
            <Trigger Property="IsKeyboardFocused" Value="True">
              <Setter Property="RenderDefaulted" TargetName="Chrome" Value="True"/>
            </Trigger>
            <Trigger Property="ToggleButton.IsChecked" Value="True">
              <Setter Property="RenderPressed" TargetName="Chrome" Value="True"/>
            </Trigger>
            <Trigger Property="IsEnabled" Value="False">
              <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
            </Trigger>
          </ControlTemplate.Triggers>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>

  <Style x:Key="ToolBarDropDownButtonStyle" TargetType="{x:Type DropDownButton:DropDownButton}">
    <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
    <Setter Property="BorderThickness" Value="1,1,1,1"/>
    <Setter Property="Background" Value="#00FFFFFF"/>
    <Setter Property="BorderBrush" Value="#00FFFFFF"/>
    <Setter Property="HorizontalAlignment" Value="Stretch"/>
    <Setter Property="VerticalAlignment" Value="Stretch"/>
    <Setter Property="HorizontalContentAlignment" Value="Stretch"/>
    <Setter Property="VerticalContentAlignment" Value="Stretch"/>
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="{x:Type DropDownButton:DropDownButton}">
          <Border SnapsToDevicePixels="True" Background="{TemplateBinding Background}" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}">
            <!--<Label>-->
            <StackPanel Orientation="Horizontal">
              <Image Margin="2,2,2,2" VerticalAlignment="Center" Width="16" Height="16" Source="{TemplateBinding Image}"/>
              <Label Content="{TemplateBinding Text}" Target="{TemplateBinding Target}" VerticalAlignment="Center" Padding="0" />
              <Path Fill="{DynamicResource GlyphBrush}" Data="M 0 0 L 4 4 L 8 0 Z"  Height="5" Margin="5,2,2,0"/>
            </StackPanel>
            <!--</Label>-->
          </Border>
          <ControlTemplate.Triggers>
            <Trigger Property="IsChecked" Value="True">
              <Setter Property="BorderBrush" Value="#FF316AC5"/>
              <Setter Property="Background" Value="#FFE1E6E8"/>
            </Trigger>
            <Trigger Property="IsMouseOver" Value="True">
              <Setter Property="BorderBrush" Value="#FF316AC5"/>
              <Setter Property="Background" Value="#FFC1D2EE"/>
            </Trigger>
            <Trigger Property="IsKeyboardFocused" Value="True">
              <Setter Property="BorderBrush" Value="#FF316AC5"/>
              <Setter Property="Background" Value="#FFC1D2EE"/>
            </Trigger>
            <MultiTrigger>
              <MultiTrigger.Conditions>
                <Condition Property="IsMouseOver" Value="True"/>
                <Condition Property="IsChecked" Value="True"/>
              </MultiTrigger.Conditions>
              <Setter Property="BorderBrush" Value="#FF4B4B6F"/>
              <Setter Property="Background" Value="#FF98B5E2"/>
            </MultiTrigger>
            <MultiTrigger>
              <MultiTrigger.Conditions>
                <Condition Property="IsKeyboardFocused" Value="True"/>
                <Condition Property="IsChecked" Value="True"/>
              </MultiTrigger.Conditions>
              <Setter Property="BorderBrush" Value="#FF4B4B6F"/>
              <Setter Property="Background" Value="#FF98B5E2"/>
            </MultiTrigger>
            <Trigger Property="IsPressed" Value="True">
              <Setter Property="BorderBrush" Value="#FF4B4B6F"/>
              <Setter Property="Background" Value="#FF98B5E2"/>
            </Trigger>
            <Trigger Property="IsEnabled" Value="False">
              <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
            </Trigger>
          </ControlTemplate.Triggers>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
  </Style>

  <DataTemplate x:Key="DropDownMenuIconStyle">
    <Image Source="{Binding XPath=.}"></Image>
  </DataTemplate>

  <ControlTemplate x:Key="DropDownMenuItemTemplate" TargetType="MenuItem">
    <Border Name="Border">
      <Grid>
        <Grid.ColumnDefinitions>
          <ColumnDefinition Width="Auto" SharedSizeGroup="Icon"/>
          <ColumnDefinition Width="*" />
          <ColumnDefinition Width="Auto" SharedSizeGroup="Shortcut"/>
          <ColumnDefinition Width="13"/>
        </Grid.ColumnDefinitions>
        <ContentPresenter x:Name="Icon"
                          ContentTemplate="{StaticResource DropDownMenuIconStyle}"
                          Margin="6,0,6,0"
                          VerticalAlignment="Center"
                          ContentSource="Icon"
                          Height="16" Width="16"/>
        <Border x:Name="Check"
                Width="13" Height="13"
                Visibility="Collapsed"
                Margin="6,0,6,0"
                Background="{StaticResource NormalBrush}"
                BorderThickness="1"
                BorderBrush="{StaticResource NormalBorderBrush}">
          <Path x:Name="CheckMark"
                Width="7" Height="7"
                Visibility="Hidden"
                SnapsToDevicePixels="False"
                Stroke="{StaticResource GlyphBrush}"
                StrokeThickness="2"
                Data="M 0 0 L 7 7 M 0 7 L 7 0" />
        </Border>
        <ContentPresenter x:Name="HeaderHost"
                          Grid.Column="1"
                          ContentSource="Header"
                          RecognizesAccessKey="True"
                          Margin="5,2,0,2"
                          VerticalAlignment="Center"/>
        <TextBlock x:Name="InputGestureText"
                   Grid.Column="2"
                   Text="{TemplateBinding InputGestureText}"
                   Margin="5,2,0,2"
                   DockPanel.Dock="Right" />
      </Grid>
    </Border>
    <ControlTemplate.Triggers>
      <Trigger Property="Icon" Value="{x:Null}">
        <Setter TargetName="Icon" Property="Visibility" Value="Hidden"/>
      </Trigger>
      <Trigger Property="IsChecked" Value="true">
        <Setter TargetName="CheckMark" Property="Visibility" Value="Visible"/>
      </Trigger>
      <Trigger Property="IsCheckable" Value="true">
        <Setter TargetName="Check" Property="Visibility" Value="Visible"/>
        <Setter TargetName="Icon" Property="Visibility" Value="Hidden"/>
      </Trigger>
      <Trigger Property="IsHighlighted" Value="true">
        <Setter TargetName="Border" Property="Background" Value="{StaticResource SelectedBackgroundBrush}"/>
      </Trigger>
      <Trigger Property="IsEnabled" Value="false">
        <Setter Property="Foreground" Value="{StaticResource DisabledForegroundBrush}"/>
      </Trigger>
    </ControlTemplate.Triggers>
  </ControlTemplate>
</ResourceDictionary>