WPF中滚动条有关问题

<ListBox Name="listbox1" Style="{StaticResource MListBox_RD}">
            <ListBox.ItemTemplate>
                <DataTemplate>
                    <Expander ExpandDirection="Down" Width="405" MaxHeight="609" ScrollViewer.VerticalScrollBarVisibility="{Binding Panduan}" Style="{StaticResource MainExpander_Frame3_3_Content_RD}">
                        <Expander.Header>
                            <!--嵌套的textblock-->
                            <TextBlock Text="{Binding DataName}" FontWeight="Bold"/>
                            <!--嵌套的textblock-->
                        </Expander.Header>
                        <Expander.Content>
                            <!--嵌套的listbox-->
                            <!--<TextBlock Text="{Binding ShowList}"/>-->
                            <ListView  ItemsSource="{Binding ShowList}" ScrollViewer.CanContentScroll="True" MouseDoubleClick="ListView_MouseDoubleClick_1" >
                                <ListView.View >
                                    <GridView>
                                        <GridViewColumn>
                                            <GridViewColumn.CellTemplate>
                                                <DataTemplate>
                                                    <TextBlock Text="{Binding Path=DataName}" Style="{StaticResource MainTextBlock_MainListBox_Content_RD}" />
                                                </DataTemplate>
                                            </GridViewColumn.CellTemplate>
                                        </GridViewColumn>
                                    </GridView>
                                </ListView.View>
                            </ListView>
                            <!--嵌套的listbox-->