作为NumBox似乎有当控制被禁用（其它控件做，当然）不调光标签的错误，我尝试的风格它迫使这种行为：

  <Style TargetType="ux:NumberBox">
    <Setter Property="HeaderTemplate">
      <Setter.Value>
        <DataTemplate>
          <TextBlock x:Name="HeaderText" Text="{Binding}" Foreground="{ThemeResource TextControlHeaderForeground}">
            <VisualStateManager.VisualStateGroups>
              <VisualStateGroup x:Name="VisualStateGroup">
                <VisualState x:Name="Disabled">
                  <VisualState.Setters>
                    <Setter Target="HeaderText.Foreground" Value="{ThemeResource SystemControlDisabledBaseMediumLowBrush}" />
                  </VisualState.Setters>
                </VisualState>
              </VisualStateGroup>
            </VisualStateManager.VisualStateGroups>
          </TextBlock>
        </DataTemplate>
      </Setter.Value>
    </Setter>
  </Style>

虽然原件Foreground还可以，但它不会吸收视觉状态的变化，并且标签保持相同的颜色。我究竟做错了什么？