TabControl在背景的背景图象

Question

我有TabControl：

    <TabControl x:Name="tabControl" BorderThickness="0" Grid.Row="1" Grid.Column="1" Grid.ColumnSpan="1" Margin="0,5,0,0">
        <TabControl.Resources>
            <Style TargetType="local:ucTabItem">
                <Setter Property="Template">
                    <Setter.Value>
                        <ControlTemplate TargetType="local:ucTabItem">
                            <Grid Name="Panel" >
                                <ContentPresenter x:Name="ContentSite"
                                    VerticalAlignment="Center"
                                    HorizontalAlignment="Center"
                                    ContentSource="Header"
                                    Margin="1,2"/>
                                <Grid.Background>
                                    <ImageBrush ImageSource="/Images/Sudanese_Police.png" AlignmentX="Center" AlignmentY="Center" Stretch="None" />
                                </Grid.Background>
                            </Grid>
                            <ControlTemplate.Triggers>
                                <Trigger Property="IsSelected" Value="True">
                                    <Setter TargetName="Panel" Property="Background" Value="{StaticResource brushTabHeaderActive}" />
                                </Trigger>
                                <Trigger Property="IsSelected" Value="False">
                                    <Setter TargetName="Panel" Property="Background" Value="{StaticResource brushTabHeaderHover}" />
                                </Trigger>
                            </ControlTemplate.Triggers>
                        </ControlTemplate>
                    </Setter.Value>
                </Setter>
            </Style>
        </TabControl.Resources>
    </TabControl>

如何设置所有标签关闭时显示的背景图像我尝试使用

<TabControl.Background>
    <ImageBrush ImageSource="/Images/BGI.png" AlignmentX="Center" AlignmentY="Center" Stretch="None" />
</TabControl.Background>

但后来我没看到背景颜色......