WPF CheckBox with flow direction

AttachedProperties.cs

using System.Collections.Generic;
using System.Windows;
using System.Windows.Controls;

namespace YourNamespace {

  public class Flow {
    public static readonly DependencyProperty DirectionProperty = DependencyProperty.RegisterAttached(
      "Direction", typeof (FlowDirection), typeof (Flow), new PropertyMetadata(default(FlowDirection)));

    public static void SetDirection(DependencyObject element, FlowDirection value) {
      element.SetValue(DirectionProperty, value);
    }

    public static FlowDirection GetDirection(DependencyObject element) {
      return (FlowDirection) element.GetValue(DirectionProperty);
    }
  }
}

Checkbox.xaml

          <Style x:Key="FocusVisual">
            <Setter Property="Control.Template">
              <Setter.Value>
                <ControlTemplate>
                  <Rectangle Margin="2" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
                </ControlTemplate>
              </Setter.Value>
            </Setter>
          </Style>
          <SolidColorBrush x:Key="OptionMark.Static.Background" Color="#FFFFFFFF"/>
          <SolidColorBrush x:Key="OptionMark.Static.Border" Color="#FF707070"/>
          <Style x:Key="OptionMarkFocusVisual">
            <Setter Property="Control.Template">
              <Setter.Value>
                <ControlTemplate>
                  <Rectangle Margin="14,0,0,0" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
                </ControlTemplate>
              </Setter.Value>
            </Setter>
          </Style>
          <SolidColorBrush x:Key="OptionMark.MouseOver.Background" Color="#FFF3F9FF"/>
          <SolidColorBrush x:Key="OptionMark.MouseOver.Border" Color="#FF5593FF"/>
          <SolidColorBrush x:Key="OptionMark.MouseOver.Glyph" Color="#FF212121"/>
          <SolidColorBrush x:Key="OptionMark.Disabled.Background" Color="#FFE6E6E6"/>
          <SolidColorBrush x:Key="OptionMark.Disabled.Border" Color="#FFBCBCBC"/>
          <SolidColorBrush x:Key="OptionMark.Disabled.Glyph" Color="#FF707070"/>
          <SolidColorBrush x:Key="OptionMark.Pressed.Background" Color="#FFD9ECFF"/>
          <SolidColorBrush x:Key="OptionMark.Pressed.Border" Color="#FF3C77DD"/>
          <SolidColorBrush x:Key="OptionMark.Pressed.Glyph" Color="#FF212121"/>
          <SolidColorBrush x:Key="OptionMark.Static.Glyph" Color="#FF212121"/>
          <Style TargetType="{x:Type CheckBox}">
            <Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}"/>
            <Setter Property="Background" Value="{StaticResource OptionMark.Static.Background}"/>
            <Setter Property="BorderBrush" Value="{StaticResource OptionMark.Static.Border}"/>
            <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
            <Setter Property="BorderThickness" Value="1"/>
            <Setter Property="Template">
              <Setter.Value>
                <ControlTemplate TargetType="{x:Type CheckBox}">
                  <Grid x:Name="templateRoot" Background="Transparent" SnapsToDevicePixels="True">
                    <Grid.ColumnDefinitions>
                      <ColumnDefinition Width="Auto"/>
                      <ColumnDefinition Width="*"/>
                    </Grid.ColumnDefinitions>
                    <Border x:Name="checkBoxBorder" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="1" VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
                      <Grid x:Name="markGrid">
                        <Path x:Name="optionMark" Data="F1 M 9.97498,1.22334L 4.6983,9.09834L 4.52164,9.09834L 0,5.19331L 1.27664,3.52165L 4.255,6.08833L 8.33331,1.52588e-005L 9.97498,1.22334 Z " Fill="{StaticResource OptionMark.Static.Glyph}" Margin="1" Opacity="0" Stretch="None"/>
                        <Rectangle x:Name="indeterminateMark" Fill="{StaticResource OptionMark.Static.Glyph}" Margin="2" Opacity="0"/>
                      </Grid>
                    </Border>
                    <ContentPresenter x:Name="contentPresenter" Grid.Column="1" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
                  </Grid>
                  <ControlTemplate.Triggers>
                    <Trigger Property="local:Flow.Direction" Value="RightToLeft">
                      <Setter Property="Grid.Column" TargetName="contentPresenter" Value="0"/>
                      <Setter Property="Grid.Column" TargetName="checkBoxBorder" Value="1"/>
                      <Setter Property="Grid.Column" TargetName="markGrid" Value="1"/>
                    </Trigger>
                    <Trigger Property="HasContent" Value="true">
                      <Setter Property="FocusVisualStyle" Value="{StaticResource OptionMarkFocusVisual}"/>
                      <Setter Property="Padding" Value="4,-1,0,0"/>
                    </Trigger>
                    <Trigger Property="IsMouseOver" Value="true">
                      <Setter Property="Background" TargetName="checkBoxBorder" Value="{StaticResource OptionMark.MouseOver.Background}"/>
                      <Setter Property="BorderBrush" TargetName="checkBoxBorder" Value="{StaticResource OptionMark.MouseOver.Border}"/>
                      <Setter Property="Fill" TargetName="optionMark" Value="{StaticResource OptionMark.MouseOver.Glyph}"/>
                      <Setter Property="Fill" TargetName="indeterminateMark" Value="{StaticResource OptionMark.MouseOver.Glyph}"/>
                    </Trigger>
                    <Trigger Property="IsEnabled" Value="false">
                      <Setter Property="Background" TargetName="checkBoxBorder" Value="{StaticResource OptionMark.Disabled.Background}"/>
                      <Setter Property="BorderBrush" TargetName="checkBoxBorder" Value="{StaticResource OptionMark.Disabled.Border}"/>
                      <Setter Property="Fill" TargetName="optionMark" Value="{StaticResource OptionMark.Disabled.Glyph}"/>
                      <Setter Property="Fill" TargetName="indeterminateMark" Value="{StaticResource OptionMark.Disabled.Glyph}"/>
                    </Trigger>
                    <Trigger Property="IsPressed" Value="true">
                      <Setter Property="Background" TargetName="checkBoxBorder" Value="{StaticResource OptionMark.Pressed.Background}"/>
                      <Setter Property="BorderBrush" TargetName="checkBoxBorder" Value="{StaticResource OptionMark.Pressed.Border}"/>
                      <Setter Property="Fill" TargetName="optionMark" Value="{StaticResource OptionMark.Pressed.Glyph}"/>
                      <Setter Property="Fill" TargetName="indeterminateMark" Value="{StaticResource OptionMark.Pressed.Glyph}"/>
                    </Trigger>
                    <Trigger Property="IsChecked" Value="true">
                      <Setter Property="Opacity" TargetName="optionMark" Value="1"/>
                      <Setter Property="Opacity" TargetName="indeterminateMark" Value="0"/>
                    </Trigger>
                    <Trigger Property="IsChecked" Value="{x:Null}">
                      <Setter Property="Opacity" TargetName="optionMark" Value="0"/>
                      <Setter Property="Opacity" TargetName="indeterminateMark" Value="1"/>
                    </Trigger>
                  </ControlTemplate.Triggers>
                </ControlTemplate>
              </Setter.Value>
            </Setter>
          </Style>

Implementation.xaml

<CheckBox Content="Do something" />
<CheckBox Content="...if this criteria is met." local:Flow.Direction="RightToLeft" />