WPF中双向绑定修改TreeViewItem前景颜色与CheckBox交互

                <TreeView Grid.Row="1" Name="mnltree" SelectedItemChanged="SelectedItemChanged" IsEnabled="False">
                    <TreeView.ItemContainerStyle >
                        <Style TargetType="{x:Type TreeViewItem}" >
                            <Setter Property="IsExpanded" Value="true" />
                        </Style>
                    </TreeView.ItemContainerStyle>
                    <TreeView.Resources>
                        <HierarchicalDataTemplate DataType="{x:Type local:TreeItem}"  ItemsSource="{Binding Path=children}" >
                            <StackPanel Orientation="Horizontal" Margin="0,2,0,2" >
                                <CheckBox Focusable="False" IsEnabled="{Binding IsEnabled,Mode=TwoWay}" IsChecked="{Binding IsChecked,Mode=TwoWay}" VerticalAlignment="Center" Click="CheckBox_Click" Checked="CheckBox_Checked" Unchecked="CheckBox_Unchecked" />
                                <TextBlock VerticalAlignment="Center" Text="{Binding Path=ItemName, Mode=TwoWay}"  Foreground="{Binding Path=Foreground, Mode=TwoWay}" ></TextBlock> 
                            </StackPanel>
                        </HierarchicalDataTemplate>
                    </TreeView.Resources>
                </TreeView>