WPF меню - нежелательные границы

Question

Я сделал простое меню WPF и изменил фон и цвета переднего плана, но есть еще граница вокруг себя и вокруг каждого сепаратора, который я не в состоянии удалить подменю:

Xaml код:

<Menu Style="{DynamicResource MainMenu}" IsMainMenu="true"> 
    <MenuItem Header="_File"> 
     <MenuItem Header="_New" Command="New"/> 
      <Separator /> 
      <MenuItem Header="_Import"/> 
      <MenuItem Header="_Export"/> 
      <Separator /> 
      <MenuItem Header="_Print..." Command="Print"/> 
      <MenuItem Header="_Print Setup..."/> 
      <Separator /> 
      <MenuItem Header="_Sign Out" /> 
      <Separator /> 
      <MenuItem Header="_Exit"/> 
     <MenuItem Header="_Edit"/> 
     <MenuItem Header="_View"/> 
     <MenuItem Header="_Tools"/> 
     <MenuItem Header="_Help"/> 
</Menu> 

Стиль:

<Style TargetType="{x:Type Menu}" x:Key="MainMenu"> 
    <Setter Property="Background" Value="#2b2b2b"/> 
    <Setter Property="Foreground" Value="White"/> 
    <Setter Property="BorderBrush" Value="#3f3f46"/> 
    <Style.Resources> 
     <Style TargetType="{x:Type MenuItem}"> 
      <Setter Property="Background" Value="#3f3f46"/> 
      <Setter Property="Foreground" Value="White"/> 
      <Setter Property="BorderBrush" Value="#3f3f46"/> 
     </Style> 
     <Style TargetType="{x:Type Separator}"> 
      <Setter Property="Background" Value="White"/> 
     </Style> 
    </Style.Resources> 
</Style> 

Answer 1

Белые линии являются частью шаблона Popup, что и используется в шаблоне по умолчанию MenuItem. Вам придется переопределить его, чтобы удалить эти прокладки.

Если у вас есть Blend, вы можете легко изменить шаблон и скопировать-вставить код в свой проект. Если у вас нет Blend, дать этому выстрел:

1- Добавить ссылку на PresentationFramework.Aero

2- В файле XAML, импортировать пространство имен:

xmlns:Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero" 

Вставьте этот код внутри раздел Window.Resources. Это то, что смешаться генерируется на основе модифицированного шаблона:

<LinearGradientBrush x:Key="MenuItemSelectionFill" EndPoint="0,1" StartPoint="0,0"> 
     <GradientStop Color="#34C5EBFF" Offset="0"/> 
     <GradientStop Color="#3481D8FF" Offset="1"/> 
    </LinearGradientBrush> 
    <Geometry x:Key="Checkmark">M 0,5.1 L 1.7,5.2 L 3.4,7.1 L 8,0.4 L 9.2,0 L 3.3,10.8 Z</Geometry> 
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=SubmenuItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}"> 
     <Grid SnapsToDevicePixels="true"> 
      <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" RadiusY="2" RadiusX="2" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/> 
      <Rectangle x:Name="InnerBorder" Margin="1" RadiusY="2" RadiusX="2"/> 
      <Grid> 
       <Grid.ColumnDefinitions> 
        <ColumnDefinition MinWidth="24" SharedSizeGroup="MenuItemIconColumnGroup" Width="Auto"/> 
        <ColumnDefinition Width="4"/> 
        <ColumnDefinition Width="*"/> 
        <ColumnDefinition Width="37"/> 
        <ColumnDefinition SharedSizeGroup="MenuItemIGTColumnGroup" Width="Auto"/> 
        <ColumnDefinition Width="17"/> 
       </Grid.ColumnDefinitions> 
       <ContentPresenter x:Name="Icon" ContentSource="Icon" Margin="1" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/> 
       <Border x:Name="GlyphPanel" BorderBrush="#CDD3E6" BorderThickness="1" Background="#E6EFF4" CornerRadius="3" Height="22" Margin="1" Visibility="Hidden" Width="22"> 
        <Path x:Name="Glyph" Data="{StaticResource Checkmark}" Fill="#0C12A1" FlowDirection="LeftToRight" Height="11" Width="9"/> 
       </Border> 
       <ContentPresenter Grid.Column="2" ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/> 
       <TextBlock Grid.Column="4" Margin="{TemplateBinding Padding}" Text="{TemplateBinding InputGestureText}"/> 
      </Grid> 
     </Grid> 
     <ControlTemplate.Triggers> 
      <Trigger Property="Icon" Value="{x:Null}"> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="IsChecked" Value="true"> 
       <Setter Property="Visibility" TargetName="GlyphPanel" Value="Visible"/> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="IsHighlighted" Value="true"> 
       <Setter Property="Fill" TargetName="Bg" Value="{StaticResource MenuItemSelectionFill}"/> 
       <Setter Property="Stroke" TargetName="Bg" Value="#8071CBF1"/> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#40FFFFFF"/> 
      </Trigger> 
      <Trigger Property="IsEnabled" Value="false"> 
       <Setter Property="Foreground" Value="#FF9A9A9A"/> 
       <Setter Property="Background" TargetName="GlyphPanel" Value="#EEE9E9"/> 
       <Setter Property="BorderBrush" TargetName="GlyphPanel" Value="#DBD6D6"/> 
       <Setter Property="Fill" TargetName="Glyph" Value="#848589"/> 
      </Trigger> 
     </ControlTemplate.Triggers> 
    </ControlTemplate> 
    <LinearGradientBrush x:Key="MenuItemPressedFill" EndPoint="0,1" StartPoint="0,0"> 
     <GradientStop Color="#28717070" Offset="0"/> 
     <GradientStop Color="#50717070" Offset="0.75"/> 
     <GradientStop Color="#90717070" Offset="1"/> 
    </LinearGradientBrush> 
    <Geometry x:Key="UpArrow">M 0,4 L 3.5,0 L 7,4 Z</Geometry> 
    <Style x:Key="MenuScrollButton" BasedOn="{x:Null}" TargetType="{x:Type RepeatButton}"> 
     <Setter Property="ClickMode" Value="Hover"/> 
     <Setter Property="MinWidth" Value="0"/> 
     <Setter Property="MinHeight" Value="0"/> 
     <Setter Property="Template"> 
      <Setter.Value> 
       <ControlTemplate TargetType="{x:Type RepeatButton}"> 
        <DockPanel Background="Transparent" SnapsToDevicePixels="true"> 
         <Rectangle x:Name="R1" DockPanel.Dock="Right" Fill="Transparent" Width="1"/> 
         <Rectangle x:Name="B1" DockPanel.Dock="Bottom" Fill="Transparent" Height="1"/> 
         <Rectangle x:Name="L1" DockPanel.Dock="Left" Fill="Transparent" Width="1"/> 
         <Rectangle x:Name="T1" DockPanel.Dock="Top" Fill="Transparent" Height="1"/> 
         <ContentPresenter x:Name="ContentContainer" HorizontalAlignment="Center" Margin="2,2,2,2" VerticalAlignment="Center"/> 
        </DockPanel> 
        <ControlTemplate.Triggers> 
         <Trigger Property="IsPressed" Value="true"> 
          <Setter Property="Fill" TargetName="R1" Value="{DynamicResource {x:Static SystemColors.ControlLightLightBrushKey}}"/> 
          <Setter Property="Fill" TargetName="B1" Value="{DynamicResource {x:Static SystemColors.ControlLightLightBrushKey}}"/> 
          <Setter Property="Fill" TargetName="L1" Value="{DynamicResource {x:Static SystemColors.ControlDarkDarkBrushKey}}"/> 
          <Setter Property="Fill" TargetName="T1" Value="{DynamicResource {x:Static SystemColors.ControlDarkDarkBrushKey}}"/> 
          <Setter Property="Margin" TargetName="ContentContainer" Value="3,3,1,1"/> 
         </Trigger> 
        </ControlTemplate.Triggers> 
       </ControlTemplate> 
      </Setter.Value> 
     </Setter> 
    </Style> 
    <MenuScrollingVisibilityConverter x:Key="MenuScrollingVisibilityConverter"/> 
    <Geometry x:Key="DownArrow">M 0,0 L 3.5,4 L 7,0 Z</Geometry> 
    <Style x:Key="{ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}" BasedOn="{x:Null}" TargetType="{x:Type ScrollViewer}"> 
     <Setter Property="HorizontalScrollBarVisibility" Value="Hidden"/> 
     <Setter Property="VerticalScrollBarVisibility" Value="Auto"/> 
     <Setter Property="Template"> 
      <Setter.Value> 
       <ControlTemplate TargetType="{x:Type ScrollViewer}"> 
        <Grid SnapsToDevicePixels="true"> 
         <Grid.ColumnDefinitions> 
          <ColumnDefinition Width="*"/> 
         </Grid.ColumnDefinitions> 
         <Grid.RowDefinitions> 
          <RowDefinition Height="Auto"/> 
          <RowDefinition Height="*"/> 
          <RowDefinition Height="Auto"/> 
         </Grid.RowDefinitions> 
         <Border Grid.Column="0" Grid.Row="1"> 
          <ScrollContentPresenter Margin="{TemplateBinding Padding}"/> 
         </Border> 
         <RepeatButton Grid.Column="0" CommandTarget="{Binding RelativeSource={RelativeSource TemplatedParent}}" Command="{x:Static ScrollBar.LineUpCommand}" Focusable="false" Grid.Row="0" Style="{StaticResource MenuScrollButton}"> 
          <RepeatButton.Visibility> 
           <MultiBinding ConverterParameter="0" Converter="{StaticResource MenuScrollingVisibilityConverter}" FallbackValue="Visibility.Collapsed"> 
            <Binding Path="ComputedVerticalScrollBarVisibility" RelativeSource="{RelativeSource TemplatedParent}"/> 
            <Binding Path="VerticalOffset" RelativeSource="{RelativeSource TemplatedParent}"/> 
            <Binding Path="ExtentHeight" RelativeSource="{RelativeSource TemplatedParent}"/> 
            <Binding Path="ViewportHeight" RelativeSource="{RelativeSource TemplatedParent}"/> 
           </MultiBinding> 
          </RepeatButton.Visibility> 
          <Path Data="{StaticResource UpArrow}" Fill="{DynamicResource {x:Static SystemColors.MenuTextBrushKey}}"/> 
         </RepeatButton> 
         <RepeatButton Grid.Column="0" CommandTarget="{Binding RelativeSource={RelativeSource TemplatedParent}}" Command="{x:Static ScrollBar.LineDownCommand}" Focusable="false" Grid.Row="2" Style="{StaticResource MenuScrollButton}"> 
          <RepeatButton.Visibility> 
           <MultiBinding ConverterParameter="100" Converter="{StaticResource MenuScrollingVisibilityConverter}" FallbackValue="Visibility.Collapsed"> 
            <Binding Path="ComputedVerticalScrollBarVisibility" RelativeSource="{RelativeSource TemplatedParent}"/> 
            <Binding Path="VerticalOffset" RelativeSource="{RelativeSource TemplatedParent}"/> 
            <Binding Path="ExtentHeight" RelativeSource="{RelativeSource TemplatedParent}"/> 
            <Binding Path="ViewportHeight" RelativeSource="{RelativeSource TemplatedParent}"/> 
           </MultiBinding> 
          </RepeatButton.Visibility> 
          <Path Data="{StaticResource DownArrow}" Fill="{DynamicResource {x:Static SystemColors.MenuTextBrushKey}}"/> 
         </RepeatButton> 
        </Grid> 
       </ControlTemplate> 
      </Setter.Value> 
     </Setter> 
    </Style> 
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=SubmenuContent, TypeInTargetAssembly={x:Type FrameworkElement}}" TargetType="{x:Type ContentControl}"> 
     <Border BorderBrush="#FF959595" BorderThickness="1" Background="#3f3f46"> 
      <Grid> 
       <ContentPresenter Grid.ColumnSpan="2" Margin="1,0"/> 
      </Grid> 
     </Border> 
    </ControlTemplate> 
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=TopLevelHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}"> 
     <Grid SnapsToDevicePixels="true"> 
      <Rectangle x:Name="OuterBorder" RadiusY="2" RadiusX="2"/> 
      <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" Margin="1" RadiusY="1" RadiusX="1" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/> 
      <Rectangle x:Name="InnerBorder" Margin="2"/> 
      <DockPanel> 
       <ContentPresenter x:Name="Icon" ContentSource="Icon" Margin="4,0,6,0" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/> 
       <Path x:Name="GlyphPanel" Data="{StaticResource Checkmark}" Fill="{TemplateBinding Foreground}" FlowDirection="LeftToRight" Margin="7,0,0,0" Visibility="Collapsed" VerticalAlignment="Center"/> 
       <ContentPresenter ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/> 
      </DockPanel> 
      <Popup x:Name="PART_Popup" AllowsTransparency="true" Focusable="false" HorizontalOffset="1" IsOpen="{Binding IsSubmenuOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}" Placement="Bottom" VerticalOffset="-1"> 
       <Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent"> 
        <ContentControl x:Name="SubMenuBorder" IsTabStop="false" Template="{DynamicResource {ComponentResourceKey ResourceId=SubmenuContent, TypeInTargetAssembly={x:Type FrameworkElement}}}"> 
         <ScrollViewer CanContentScroll="true" Style="{DynamicResource {ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}}"> 
          <ItemsPresenter KeyboardNavigation.DirectionalNavigation="Cycle" Grid.IsSharedSizeScope="true" Margin="2" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" KeyboardNavigation.TabNavigation="Cycle"/> 
         </ScrollViewer> 
        </ContentControl> 
       </Themes:SystemDropShadowChrome> 
      </Popup> 
     </Grid> 
     <ControlTemplate.Triggers> 
      <Trigger Property="IsSuspendingPopupAnimation" Value="true"> 
       <Setter Property="PopupAnimation" TargetName="PART_Popup" Value="None"/> 
      </Trigger> 
      <Trigger Property="Icon" Value="{x:Null}"> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="IsChecked" Value="true"> 
       <Setter Property="Visibility" TargetName="GlyphPanel" Value="Visible"/> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true"> 
       <Setter Property="Margin" TargetName="Shdw" Value="0,0,5,5"/> 
       <Setter Property="Color" TargetName="Shdw" Value="#71000000"/> 
      </Trigger> 
      <Trigger Property="IsHighlighted" Value="true"> 
       <Setter Property="Stroke" TargetName="Bg" Value="#90717070"/> 
       <Setter Property="Stroke" TargetName="OuterBorder" Value="#50FFFFFF"/> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#50FFFFFF"/> 
      </Trigger> 
      <Trigger Property="IsKeyboardFocused" Value="true"> 
       <Setter Property="Stroke" TargetName="Bg" Value="#E0717070"/> 
       <Setter Property="Fill" TargetName="Bg" Value="{StaticResource MenuItemPressedFill}"/> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#50747272"/> 
      </Trigger> 
      <Trigger Property="IsSubmenuOpen" Value="true"> 
       <Setter Property="Stroke" TargetName="Bg" Value="#E0717070"/> 
       <Setter Property="Fill" TargetName="Bg" Value="{StaticResource MenuItemPressedFill}"/> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#50747272"/> 
      </Trigger> 
      <Trigger Property="IsEnabled" Value="false"> 
       <Setter Property="Foreground" Value="#FF9A9A9A"/> 
       <Setter Property="Fill" TargetName="GlyphPanel" Value="#848589"/> 
      </Trigger> 
     </ControlTemplate.Triggers> 
    </ControlTemplate> 
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=TopLevelItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}"> 
     <Grid SnapsToDevicePixels="true"> 
      <Rectangle x:Name="OuterBorder" RadiusY="2" RadiusX="2"/> 
      <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" Margin="1" RadiusY="1" RadiusX="1" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/> 
      <Rectangle x:Name="InnerBorder" Margin="2"/> 
      <DockPanel> 
       <ContentPresenter x:Name="Icon" ContentSource="Icon" Margin="4,0,6,0" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/> 
       <Path x:Name="GlyphPanel" Data="{StaticResource Checkmark}" Fill="{TemplateBinding Foreground}" FlowDirection="LeftToRight" Margin="7,0,0,0" Visibility="Collapsed" VerticalAlignment="Center"/> 
       <ContentPresenter ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/> 
      </DockPanel> 
     </Grid> 
     <ControlTemplate.Triggers> 
      <Trigger Property="Icon" Value="{x:Null}"> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="IsChecked" Value="true"> 
       <Setter Property="Visibility" TargetName="GlyphPanel" Value="Visible"/> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="IsHighlighted" Value="true"> 
       <Setter Property="Stroke" TargetName="Bg" Value="#90717070"/> 
       <Setter Property="Stroke" TargetName="OuterBorder" Value="#50FFFFFF"/> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#50FFFFFF"/> 
      </Trigger> 
      <Trigger Property="IsKeyboardFocused" Value="true"> 
       <Setter Property="Stroke" TargetName="Bg" Value="#E0717070"/> 
       <Setter Property="Fill" TargetName="Bg" Value="{StaticResource MenuItemPressedFill}"/> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#50747272"/> 
      </Trigger> 
      <Trigger Property="IsEnabled" Value="false"> 
       <Setter Property="Foreground" Value="#FF9A9A9A"/> 
       <Setter Property="Fill" TargetName="GlyphPanel" Value="#848589"/> 
      </Trigger> 
     </ControlTemplate.Triggers> 
    </ControlTemplate> 
    <Geometry x:Key="RightArrow">M 0,0 L 4,3.5 L 0,7 Z</Geometry> 
    <ControlTemplate x:Key="{ComponentResourceKey ResourceId=SubmenuHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}"> 
     <Grid SnapsToDevicePixels="true"> 
      <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" RadiusY="2" RadiusX="2" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/> 
      <Rectangle x:Name="InnerBorder" Margin="1" RadiusY="2" RadiusX="2" Stroke="Transparent" StrokeThickness="1"/> 
      <Grid> 
       <Grid.ColumnDefinitions> 
        <ColumnDefinition MinWidth="24" SharedSizeGroup="MenuItemIconColumnGroup" Width="Auto"/> 
        <ColumnDefinition Width="4"/> 
        <ColumnDefinition Width="*"/> 
        <ColumnDefinition Width="37"/> 
        <ColumnDefinition SharedSizeGroup="MenuItemIGTColumnGroup" Width="Auto"/> 
        <ColumnDefinition Width="17"/> 
       </Grid.ColumnDefinitions> 
       <ContentPresenter x:Name="Icon" ContentSource="Icon" Margin="1" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="Center"/> 
       <Border x:Name="GlyphPanel" BorderBrush="#CDD3E6" BorderThickness="1" Background="#E6EFF4" CornerRadius="3" Height="22" Margin="1" Visibility="Hidden" Width="22"> 
        <Path x:Name="Glyph" Data="{StaticResource Checkmark}" Fill="#0C12A1" FlowDirection="LeftToRight" Height="11" Width="9"/> 
       </Border> 
       <ContentPresenter Grid.Column="2" ContentSource="Header" Margin="{TemplateBinding Padding}" RecognizesAccessKey="True" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/> 
       <TextBlock Grid.Column="4" Margin="{TemplateBinding Padding}" Text="{TemplateBinding InputGestureText}" Visibility="Collapsed"/> 
       <Path Grid.Column="5" Data="{StaticResource RightArrow}" Fill="{TemplateBinding Foreground}" Margin="4,0,0,0" VerticalAlignment="Center"/> 
      </Grid> 
      <Popup x:Name="PART_Popup" AllowsTransparency="true" Focusable="false" HorizontalOffset="-2" IsOpen="{Binding IsSubmenuOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}" Placement="Right" VerticalOffset="-3"> 
       <Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent"> 
        <ContentControl x:Name="SubMenuBorder" IsTabStop="false" Template="{DynamicResource {ComponentResourceKey ResourceId=SubmenuContent, TypeInTargetAssembly={x:Type FrameworkElement}}}"> 
         <ScrollViewer CanContentScroll="true" Style="{DynamicResource {ComponentResourceKey ResourceId=MenuScrollViewer, TypeInTargetAssembly={x:Type FrameworkElement}}}"> 
          <ItemsPresenter KeyboardNavigation.DirectionalNavigation="Cycle" Grid.IsSharedSizeScope="true" Margin="2" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" KeyboardNavigation.TabNavigation="Cycle"/> 
         </ScrollViewer> 
        </ContentControl> 
       </Themes:SystemDropShadowChrome> 
      </Popup> 
     </Grid> 
     <ControlTemplate.Triggers> 
      <Trigger Property="IsSuspendingPopupAnimation" Value="true"> 
       <Setter Property="PopupAnimation" TargetName="PART_Popup" Value="None"/> 
      </Trigger> 
      <Trigger Property="IsHighlighted" Value="true"> 
       <Setter Property="Stroke" TargetName="InnerBorder" Value="#D1DBF4FF"/> 
      </Trigger> 
      <Trigger Property="Icon" Value="{x:Null}"> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="IsChecked" Value="true"> 
       <Setter Property="Visibility" TargetName="GlyphPanel" Value="Visible"/> 
       <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/> 
      </Trigger> 
      <Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true"> 
       <Setter Property="Margin" TargetName="Shdw" Value="0,0,5,5"/> 
       <Setter Property="Color" TargetName="Shdw" Value="#71000000"/> 
      </Trigger> 
      <Trigger Property="IsHighlighted" Value="true"> 
       <Setter Property="Fill" TargetName="Bg" Value="{StaticResource MenuItemSelectionFill}"/> 
       <Setter Property="Stroke" TargetName="Bg" Value="#8571CBF1"/> 
      </Trigger> 
      <Trigger Property="IsEnabled" Value="false"> 
       <Setter Property="Foreground" Value="#FF9A9A9A"/> 
       <Setter Property="Background" TargetName="GlyphPanel" Value="#EEE9E9"/> 
       <Setter Property="BorderBrush" TargetName="GlyphPanel" Value="#DBD6D6"/> 
       <Setter Property="Fill" TargetName="Glyph" Value="#848589"/> 
      </Trigger> 
     </ControlTemplate.Triggers> 
    </ControlTemplate> 
    <Style x:Key="MenuItemStyle1" TargetType="{x:Type MenuItem}"> 
     <Setter Property="HorizontalContentAlignment" Value="{Binding HorizontalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/> 
     <Setter Property="VerticalContentAlignment" Value="{Binding VerticalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/> 
     <Setter Property="Background" Value="Transparent"/> 
     <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=SubmenuItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/> 
     <Style.Triggers> 
      <Trigger Property="Role" Value="TopLevelHeader"> 
       <Setter Property="Padding" Value="7,2,8,3"/> 
       <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=TopLevelHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/> 
      </Trigger> 
      <Trigger Property="Role" Value="TopLevelItem"> 
       <Setter Property="Padding" Value="7,2,8,3"/> 
       <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=TopLevelItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/> 
      </Trigger> 
      <Trigger Property="Role" Value="SubmenuHeader"> 
       <Setter Property="Padding" Value="2,3,2,3"/> 
       <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=SubmenuHeaderTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/> 
      </Trigger> 
      <Trigger Property="Role" Value="SubmenuItem"> 
       <Setter Property="Padding" Value="2,3,2,3"/> 
      </Trigger> 
     </Style.Triggers> 
    </Style> 

Пусть ваш Menu еще использовать MainMenu стиль, но есть каждый суб MenuItem использовать Blend, стиль генерируемый. Например, попробуйте

<MenuItem Header="_File" Style="{DynamicResource MenuItemStyle1}"> 

Это будет выглядеть следующим образом:

Не уверен, насколько близко это к тому, что вы ищете, но следует надеяться поставить вас на правильном пути.