我使用的是一个组合框样式，如here所示。
但是，当鼠标移到ComboBoxItem上时，这个示例似乎没有突出显示ComboBoxItem。我试图添加此功能，但我有一个困难的时间。高亮显示似乎起作用，但只有在用户单击后，下拉菜单消失，然后重新打开。我需要它突出显示，只要用户悬停在它的鼠标。
以下是我目前的风格：

<ControlTemplate x:Key="ComboBoxToggleButton"
                 TargetType="{x:Type ToggleButton}">
        <Grid>
            <Grid.ColumnDefinitions>
                <ColumnDefinition />
                <ColumnDefinition Width="20" />
            </Grid.ColumnDefinitions>
            <VisualStateManager.VisualStateGroups>
                <VisualStateGroup x:Name="CommonStates">
                    <VisualState x:Name="Normal" />
                    <VisualState x:Name="MouseOver">
                        <Storyboard>
                            <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Panel.Background).
                (GradientBrush.GradientStops)[1].(GradientStop.Color)"
                                          Storyboard.TargetName="Border">
                                <EasingColorKeyFrame KeyTime="0"
                                   Value="{DynamicResource MainButtonMouseOverLightEnd}" />
                            </ColorAnimationUsingKeyFrames>
                        </Storyboard>
                    </VisualState>
                    <VisualState x:Name="Pressed" />
                    <VisualState x:Name="Disabled">
                        <Storyboard>
                            <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Panel.Background).
                (GradientBrush.GradientStops)[1].(GradientStop.Color)"
                                          Storyboard.TargetName="Border">
                                <EasingColorKeyFrame KeyTime="0"
                                   Value="{StaticResource DisabledControlDarkColor}" />
                            </ColorAnimationUsingKeyFrames>
                            <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Shape.Fill).
                (SolidColorBrush.Color)"
                                          Storyboard.TargetName="Arrow">
                                <EasingColorKeyFrame KeyTime="0"
                                   Value="{StaticResource DisabledForegroundColor}" />
                            </ColorAnimationUsingKeyFrames>
                            <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Border.BorderBrush).
                (GradientBrush.GradientStops)[1].(GradientStop.Color)"
                                          Storyboard.TargetName="Border">
                                <EasingColorKeyFrame KeyTime="0"
                                   Value="{StaticResource DisabledBorderDarkColor}" />
                            </ColorAnimationUsingKeyFrames>
                        </Storyboard>
                    </VisualState>
                </VisualStateGroup>
                <VisualStateGroup x:Name="CheckStates">
                    <VisualState x:Name="Checked">
                        <Storyboard>
                            <ColorAnimationUsingKeyFrames Storyboard.TargetProperty="(Panel.Background).
                (GradientBrush.GradientStops)[1].(GradientStop.Color)"
                                          Storyboard.TargetName="Border">
                                <EasingColorKeyFrame KeyTime="0"
                                   Value="{DynamicResource MainButtonColorLightEnd}" />
                            </ColorAnimationUsingKeyFrames>
                        </Storyboard>
                    </VisualState>
                    <VisualState x:Name="Unchecked" />
                    <VisualState x:Name="Indeterminate" />
                </VisualStateGroup>
            </VisualStateManager.VisualStateGroups>
            <Border x:Name="Border"
            Grid.ColumnSpan="2"
            CornerRadius="2"
            BorderThickness="1">
                <Border.BorderBrush>
                    <LinearGradientBrush EndPoint="0,1"
                             StartPoint="0,0">
                        <GradientStop Color="{DynamicResource MainButtonMouseOverDarkStart}"
                        Offset="0" />
                        <GradientStop Color="{DynamicResource MainButtonMouseOverDarkEnd}"
                        Offset="1" />
                    </LinearGradientBrush>
                </Border.BorderBrush>
                <Border.Background>

                    <LinearGradientBrush StartPoint="0,0"
                             EndPoint="0,1">
                        <LinearGradientBrush.GradientStops>
                            <GradientStopCollection>
                                <GradientStop Color="{DynamicResource MainButtonMouseOverDarkStart}" />
                                <GradientStop Color="{DynamicResource MainButtonMouseOverDarkEnd}"
                            Offset="1.0" />
                            </GradientStopCollection>
                        </LinearGradientBrush.GradientStops>
                    </LinearGradientBrush>

                </Border.Background>
            </Border>
            <Border Grid.Column="0"
            CornerRadius="2,0,0,2"
            Margin="1" >
                <Border.Background>
                    <SolidColorBrush Color="{DynamicResource ControlLightColor}"/>
                </Border.Background>
            </Border>
            <Path x:Name="Arrow"
          Grid.Column="1"
          HorizontalAlignment="Center"
          VerticalAlignment="Center"
          Data="M 0 0 L 4 4 L 8 0 Z" >
                <Path.Fill>
                    <SolidColorBrush Color="White"/>
                </Path.Fill>
            </Path>
        </Grid>
    </ControlTemplate>

    <ControlTemplate x:Key="ComboBoxTextBox"
                 TargetType="{x:Type TextBox}">
        <Border x:Name="PART_ContentHost"
          Focusable="True"
          Background="{TemplateBinding Background}" />
    </ControlTemplate>

    <Style x:Key="{x:Type ComboBox}"
       TargetType="{x:Type ComboBox}">
        <Setter Property="SnapsToDevicePixels"
          Value="true" />
        <Setter Property="OverridesDefaultStyle"
          Value="true" />
        <Setter Property="ScrollViewer.HorizontalScrollBarVisibility"
          Value="Auto" />
        <Setter Property="ScrollViewer.VerticalScrollBarVisibility"
          Value="Auto" />
        <Setter Property="ScrollViewer.CanContentScroll"
          Value="true" />
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ComboBox}">
                    <Grid>
                        <VisualStateManager.VisualStateGroups>
                            <VisualStateGroup x:Name="CommonStates">
                                <VisualState x:Name="Normal" />
                                <VisualState x:Name="MouseOver" />
                                <VisualState x:Name="Disabled">
                                    <Storyboard>
                                        <ColorAnimationUsingKeyFrames Storyboard.TargetName="PART_EditableTextBox"
                                                Storyboard.TargetProperty="(TextElement.Foreground).
                      (SolidColorBrush.Color)">
                                            <EasingColorKeyFrame KeyTime="0"
                                         Value="{StaticResource DisabledForegroundColor}" />
                                        </ColorAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                            </VisualStateGroup>
                            <VisualStateGroup x:Name="EditStates">
                                <VisualState x:Name="Editable">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)"
                                                 Storyboard.TargetName="PART_EditableTextBox">
                                            <DiscreteObjectKeyFrame KeyTime="0"
                                            Value="{x:Static Visibility.Visible}" />
                                        </ObjectAnimationUsingKeyFrames>
                                        <ObjectAnimationUsingKeyFrames
                      Storyboard.TargetProperty="(UIElement.Visibility)"
                                                 Storyboard.TargetName="ContentSite">
                                            <DiscreteObjectKeyFrame KeyTime="0"
                                            Value="{x:Static Visibility.Hidden}" />
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="Uneditable" />
                            </VisualStateGroup>
                        </VisualStateManager.VisualStateGroups>
                        <ToggleButton x:Name="ToggleButton"
                        Template="{StaticResource ComboBoxToggleButton}"
                        Grid.Column="2"
                        Focusable="false"
                        ClickMode="Press"
                        IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, 
              RelativeSource={RelativeSource TemplatedParent}}"/>
                        <ContentPresenter x:Name="ContentSite"
                            IsHitTestVisible="False"
                            Content="{TemplateBinding SelectionBoxItem}"
                            ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
                            ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
                            Margin="3,3,23,3"
                            VerticalAlignment="Stretch"
                            HorizontalAlignment="Left">
                        </ContentPresenter>
                        <TextBox x:Name="PART_EditableTextBox"
                   Style="{x:Null}"
                   Template="{StaticResource ComboBoxTextBox}"
                   HorizontalAlignment="Left"
                   VerticalAlignment="Bottom"
                   Margin="3,3,23,3"
                   Focusable="True"
                   Background="Transparent"
                   Visibility="Hidden"
                   IsReadOnly="{TemplateBinding IsReadOnly}" />
                        <Popup x:Name="Popup"
                 Placement="Bottom"
                 IsOpen="{TemplateBinding IsDropDownOpen}"
                 AllowsTransparency="True"
                 Focusable="true"
                 PopupAnimation="Slide">
                            <Grid x:Name="DropDown"
                  SnapsToDevicePixels="True"
                  MinWidth="{TemplateBinding ActualWidth}"
                  MaxHeight="{TemplateBinding MaxDropDownHeight}">
                                <Border x:Name="DropDownBorder"
                      BorderThickness="1">
                                    <Border.BorderBrush>
                                        <SolidColorBrush Color="{DynamicResource BorderMediumColor}" />
                                    </Border.BorderBrush>
                                    <Border.Background>
                                        <SolidColorBrush Color="{DynamicResource ControlLightColor}" />
                                    </Border.Background>
                                </Border>
                                <ScrollViewer Margin="4,6,4,6"
                            SnapsToDevicePixels="True">
                                    <StackPanel IsItemsHost="True"
                            KeyboardNavigation.DirectionalNavigation="Contained" />
                                </ScrollViewer>
                            </Grid>
                        </Popup>
                    </Grid>
                    <ControlTemplate.Triggers>
                        <Trigger Property="HasItems"
                   Value="false">
                            <Setter TargetName="DropDownBorder"
                    Property="MinHeight"
                    Value="95" />
                        </Trigger>
                        <Trigger Property="IsGrouping"
                   Value="true">
                            <Setter Property="ScrollViewer.CanContentScroll"
                    Value="false" />
                        </Trigger>
                        <Trigger SourceName="Popup"
                   Property="AllowsTransparency"
                   Value="true">
                            <Setter TargetName="DropDownBorder"
                    Property="CornerRadius"
                    Value="4" />
                            <Setter TargetName="DropDownBorder"
                    Property="Margin"
                    Value="0,2,0,0" />
                        </Trigger>
                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

    <Style x:Key="{x:Type ComboBoxItem}"
       TargetType="{x:Type ComboBoxItem}">
        <Setter Property="SnapsToDevicePixels"
          Value="true" />
        <Setter Property="OverridesDefaultStyle"
          Value="true" />
        <Setter Property="Focusable" Value="True"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type ComboBoxItem}">
                    <Border x:Name="Border"
                        Padding="2"
                        SnapsToDevicePixels="true"
                        Background="Transparent">
                        <VisualStateManager.VisualStateGroups>
                            <VisualStateGroup x:Name="SelectionStates">
                                <VisualState x:Name="Unselected"/>
                                <VisualState x:Name="MouseOver">
                                    <Storyboard>
                                        <ColorAnimationUsingKeyFrames Storyboard.TargetName="Border"
                                                Storyboard.TargetProperty="(Panel.Background).
                    (SolidColorBrush.Color)">
                                            <EasingColorKeyFrame KeyTime="0"
                                         Value="Blue" />
                                        </ColorAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                            </VisualStateGroup>
                        </VisualStateManager.VisualStateGroups>
                        <ContentPresenter />
                    </Border>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>