WPF: How to set a Label style when the target TextBox has focus?

I would like to highlight a label when the associated textbox has focus. This works:

<Label Grid.Row="1" Grid.Column="0" Target="{Binding ElementName=CountryCode}">
   <Label.Style>
    <Style TargetType="{x:Type Label}">
      <Style.Triggers>
          <DataTrigger Binding="{Binding ElementName=CountryCode, Path=(IsFocused)}" Value="True">
              <Setter Property="Foreground" Value="Blue" />
          </DataTrigger>
      </Style.Triggers>
    </Style>
   </Label.Style>
   <AccessText Text="{Binding Path=CountryCodeLabel}" />
</Label>
<TextBox Grid.Row="1" Grid.Column="1" Name="CountryCode" Text="{Binding Path=CountryC开发者_运维知识库ode}" />

But I have a bunch of these textboxes, so I'd prefer to template the style. This works:

<Style x:Key="HighlightOnFocus" TargetType="{x:Type Label}">
<Style.Triggers>
   <DataTrigger Binding="{Binding ElementName=CountryCode, Path=(IsFocused)}" Value="True">
       <Setter Property="Foreground" Value="Blue" />
   </DataTrigger>
</Style.Triggers>
</Style>
...
<Label Grid.Row="1" Grid.Column="0" Style="{StaticResource HighlightOnFocus}">
   <AccessText Text="{Binding Path=CountryCodeLabel}" />
</Label>
<TextBox Grid.Row="1" Grid.Column="1" Name="CountryCode" Text="{Binding Path=CountryCode}" />

but of course I can't hard code the ElementName in there. So I tried this:

<Style x:Key="HighlightOnFocus" TargetType="{x:Type Label}">
<Style.Triggers>
   <DataTrigger Binding="{Binding Path=(IsFocused)}" Value="True">
       <Setter Property="Foreground" Value="Blue" />
   </DataTrigger>
</Style.Triggers>
</Style>
...
<Label Grid.Row="1" Grid.Column="0" Style="{StaticResource HighlightOnFocus}" DataContext="{Binding ElementName=CountryCode}">
   <AccessText Text="{Binding Path=CountryCodeLabel}" />
</Label>
<TextBox Grid.Row="1" Grid.Column="1" Name="CountryCode" Text="{Binding Path=CountryCode}" />

But setting the DataContext in the label messes up the binding in my AccessText element. So the question is - is there a way specify the element name for the style datatrigger in some way other than setting the datacontext? Is there a better way to accomplish what I'm trying to do?

There is a nice solution over here: https://social.msdn.microsoft.com/Forums/vstudio/en-US/627e4d27-351b-4e2d-86a3-9367af3f0edf/how-to-set-a-label-style-when-the-target-textbox-has-focus?forum=wpf

In general, it's fairly easy. Create a custom attached property like this:

public static class CustomAttached
{
    public static readonly DependencyProperty IsTargetFocusedProperty = DependencyProperty.RegisterAttached(
        "IsTargetFocused", typeof(bool), typeof(CustomAttached),
        new FrameworkPropertyMetadata(false, FrameworkPropertyMetadataOptions.AffectsRender)
    );
    public static void SetIsTargetFocused(UIElement element, bool value)
    {
        element.SetValue(IsTargetFocusedProperty, value);
    }
    public static bool GetIsTargetFocused(UIElement element)
    {
        return (bool)element.GetValue(IsTargetFocusedProperty);
    }
}

Then add a style for the highlighting:

<Window.Resources>
    <Style x:Key="HighlightOnFocus" TargetType="{x:Type Label}">
        <Style.Triggers>
            <Trigger Property="local:CustomAttached.IsTargetFocused" Value="True">
                <Setter Property="Background" Value="CadetBlue" />
            </Trigger>
        </Style.Triggers>
    </Style>
</Window.Resources>

And then simply use it like that:

<Label Content="Label" Style="{StaticResource HighlightOnFocus}"
    local:CustomAttached.IsTargetFocused="{Binding IsFocused, ElementName=textBox}">
</Label>
<TextBox x:Name="textBox" Text="TextBox" />