我基于最新的 WPF 扩展工具包样式创建了简单的 MahApps.Metro 自定义CheckComboBox样式。它可能并不完美，但对我有用™。
结果：
以下是主窗口资源标签中的样式：
<Window.Resources>
<xctk:InverseBoolConverter x:Key="InverseBoolConverter" />
<Style BasedOn="{StaticResource {x:Type xctk:SelectorItem}}" TargetType="{x:Type xctk:SelectorItem}">
<Setter Property="Foreground" Value="{DynamicResource TextBrush}" />
<Setter Property="Padding" Value="2" />
<Setter Property="RenderOptions.ClearTypeHint" Value="Enabled" />
<Setter Property="Background" Value="{DynamicResource WhiteBrush}" />
<Setter Property="BorderThickness" Value="0" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type xctk:SelectorItem}">
<Grid Margin="0,0.5" Background="{TemplateBinding Background}">
<Border x:Name="_background"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
<CheckBox Margin="0.5,0"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
Content="{TemplateBinding Content}"
ContentTemplate="{TemplateBinding ContentTemplate}"
ContentTemplateSelector="{TemplateBinding ContentTemplateSelector}"
Foreground="{TemplateBinding Foreground}"
IsChecked="{Binding IsSelected, RelativeSource={RelativeSource TemplatedParent}}"
Padding="{TemplateBinding Padding}" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="true">
<Setter TargetName="_background" Property="Background" Value="{DynamicResource AccentColorBrush}" />
<Setter Property="Foreground" Value="{DynamicResource AccentSelectedColorBrush}" />
</Trigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter TargetName="_background" Property="Background" Value="{DynamicResource AccentColorBrush2}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="CheckComboBoxToggleButton" TargetType="{x:Type ToggleButton}">
<Setter Property="OverridesDefaultStyle" Value="true" />
<Setter Property="IsTabStop" Value="false" />
<Setter Property="Focusable" Value="false" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Grid>
<Border x:Name="Background"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
<Grid Margin="1">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="0" MinWidth="{Binding RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type Grid}}, Path=ActualHeight, Mode=OneWay}" />
</Grid.ColumnDefinitions>
<TextBox Margin="1"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
Background="Transparent"
BorderThickness="0"
Cursor="Arrow"
Focusable="False"
HorizontalScrollBarVisibility="Hidden"
IsReadOnly="True"
Padding="{TemplateBinding Padding}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
Text="{TemplateBinding Content}"
VerticalScrollBarVisibility="Hidden" />
<Grid x:Name="ArrowBackground"
Grid.Column="1"
Background="Transparent">
<Path x:Name="Arrow"
Width="8"
Height="4"
HorizontalAlignment="Center"
VerticalAlignment="Center"
Data="F1 M 301.14,-189.041L 311.57,-189.041L 306.355,-182.942L 301.14,-189.041 Z "
Fill="{DynamicResource GrayBrush1}"
IsHitTestVisible="false"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
Stretch="Uniform" />
</Grid>
</Grid>
</Grid>
<ControlTemplate.Triggers>
<Trigger SourceName="ArrowBackground" Property="IsMouseOver" Value="True">
<Setter TargetName="ArrowBackground" Property="Background" Value="{DynamicResource GrayBrush5}" />
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="Background" Property="Background" Value="{DynamicResource GrayBrush8}" />
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter TargetName="Background" Property="Background" Value="{DynamicResource GrayBrush7}" />
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter TargetName="Arrow" Property="Fill" Value="#AFAFAF" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style BasedOn="{StaticResource {x:Type xctk:CheckComboBox}}" TargetType="{x:Type xctk:CheckComboBox}">
<Setter Property="MinHeight" Value="26" />
<Setter Property="Foreground" Value="{DynamicResource TextBrush}" />
<Setter Property="Background" Value="{DynamicResource ControlBackgroundBrush}" />
<Setter Property="BorderBrush" Value="{DynamicResource TextBoxBorderBrush}" />
<Setter Property="BorderThickness" Value="1" />
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto" />
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto" />
<Setter Property="Padding" Value="1" />
<Setter Property="ScrollViewer.PanningMode" Value="Both" />
<Setter Property="Stylus.IsFlicksEnabled" Value="False" />
<Setter Property="VerticalContentAlignment" Value="Center" />
<Setter Property="HorizontalContentAlignment" Value="Stretch" />
<Setter Property="FontFamily" Value="{DynamicResource ContentFontFamily}" />
<Setter Property="FontSize" Value="{DynamicResource ContentFontSize}" />
<Setter Property="SnapsToDevicePixels" Value="True" />
<Setter Property="Validation.ErrorTemplate" Value="{DynamicResource ValidationErrorTemplate}" />
<Setter Property="ScrollViewer.CanContentScroll" Value="False" />
<Setter Property="Controls:ControlsHelper.FocusBorderBrush" Value="{DynamicResource ComboBoxMouseOverInnerBorderBrush}" />
<Setter Property="Controls:ControlsHelper.MouseOverBorderBrush" Value="{DynamicResource TextBoxMouseOverBorderBrush}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type xctk:CheckComboBox}">
<Grid x:Name="MainGrid" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}">
<Popup x:Name="PART_Popup"
AllowsTransparency="true"
Focusable="False"
IsOpen="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
Placement="Bottom"
PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}"
StaysOpen="False">
<Grid MinWidth="{Binding ActualWidth, ElementName=MainGrid}" MaxHeight="{Binding MaxDropDownHeight, RelativeSource={RelativeSource TemplatedParent}}">
<Border x:Name="DropDownBorder"
Height="Auto"
Background="{DynamicResource WhiteBrush}"
BorderBrush="{DynamicResource ComboBoxPopupBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Effect="{DynamicResource DropShadowBrush}" />
<ScrollViewer x:Name="DropDownScrollViewer"
BorderThickness="0"
Padding="1">
<ItemsPresenter x:Name="PART_ItemsPresenter"
KeyboardNavigation.DirectionalNavigation="Contained"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
</ScrollViewer>
</Grid>
</Popup>
<Border Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
<ToggleButton x:Name="PART_DropDownButton"
Margin="0"
VerticalAlignment="Stretch"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Content="{TemplateBinding Text}"
Focusable="False"
Foreground="{TemplateBinding Foreground}"
IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
IsHitTestVisible="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource InverseBoolConverter}}"
Padding="{TemplateBinding Padding}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
Style="{DynamicResource CheckComboBoxToggleButton}" />
<Border x:Name="FocusBorder"
Background="{x:Null}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
Visibility="Collapsed" />
<Border x:Name="DisabledVisualElement"
Background="{DynamicResource ControlsDisabledBrush}"
BorderBrush="{DynamicResource ControlsDisabledBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
IsHitTestVisible="False"
Opacity="0.6"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
Visibility="Collapsed" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter TargetName="FocusBorder" Property="Visibility" Value="Visible" />
<Setter TargetName="FocusBorder" Property="BorderBrush" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(Controls:ControlsHelper.MouseOverBorderBrush)}" />
</Trigger>
<Trigger Property="IsFocused" Value="True">
<Setter TargetName="FocusBorder" Property="Visibility" Value="Visible" />
<Setter TargetName="FocusBorder" Property="BorderBrush" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(Controls:ControlsHelper.FocusBorderBrush)}" />
</Trigger>
<Trigger Property="IsKeyboardFocusWithin" Value="True">
<Setter TargetName="FocusBorder" Property="Visibility" Value="Visible" />
<Setter TargetName="FocusBorder" Property="BorderBrush" Value="{Binding RelativeSource={RelativeSource TemplatedParent}, Path=(Controls:ControlsHelper.FocusBorderBrush)}" />
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="DisabledVisualElement" Property="Visibility" Value="Visible" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
