WPF TreeView虚拟化问题

Question

我创建了一个支持虚拟化的MultiSelection树视图。 当我尝试扩展它并添加列时，虚拟化就会停止工作。

使用Snoop，并依赖以前的帖子，我尝试设置VirtualizingStackPanel.IsVirtualizing =＆＃34; True＆＃34;和ScrollViewer.CanContentScroll =＆＃34; True＆＃34;在树和卷轴上。不好......

工作树的xaml非常简单 - 没有样式（除了扩展所有项目）我将新树（有列）放在旧树（同一主网格）旁边。它的格式如下：

   <window:TreeListView Grid.Row="0" ItemsSource="{Binding Path=Coverages}" x:Name="MainTree" Margin="4,0,0,0" GridViewColumnHeader.Click="TreeListView_ColumnHeaderClicked" Loaded="MainTree_OnLoaded" Unloaded="MainTree_OnUnloaded" PreviewMouseRightButtonUp="ShowContextMenu" VirtualizingStackPanel.IsVirtualizing="True" VirtualizingStackPanel.VirtualizationMode="Recycling"  >
                <window:TreeListView.Resources>
                    <HierarchicalDataTemplate DataType="{x:Type window:CoverageSummary}" ItemsSource="{Binding CoveredProjects}" />
                    <HierarchicalDataTemplate DataType="{x:Type window:ProjectCoverageSummary}" ItemsSource="{Binding CoveredPrograms}" />
                    <HierarchicalDataTemplate DataType="{x:Type window:ProgramCoverageSummary}" ItemsSource="{Binding ElementsSummaryList}" />
                </window:TreeListView.Resources>              
                    <window:TreeListView.Columns>
                    <GridViewColumn>
                        <GridViewColumnHeader Style="{StaticResource ColumnHeaderStyle}" Content="{x:Static codeCoverageNs:Resources.HierarchyColumnTitle}" Name="Hierarchy"/>
                        <GridViewColumn.CellTemplate>
                            <DataTemplate>
                                <StackPanel Orientation="Horizontal" Tag="{Binding}" Margin="0,2,0,2">
                                    <window:TreeListViewExpander/>
                                    <Image Style="{StaticResource TreeEntryImageStyle}" />
                                    <TextBlock Text="{Binding SummaryType, Converter={StaticResource EnumToStringConverter}}" Tag="{Binding}" VerticalAlignment="Center" Visibility="{Binding SummaryType, Converter={StaticResource SummaryBlockTypeVisibilityConverter}}" />
                                    <TextBlock Text=":__ " Tag="{Binding}" VerticalAlignment="Center" Visibility="{Binding SummaryType, Converter={StaticResource SummaryBlockTypeVisibilityConverter}}"/>
                                    <TextBlock Text="{Binding SummaryName}" VerticalAlignment="Center"/>
                                </StackPanel>
                            </DataTemplate>
                        </GridViewColumn.CellTemplate>
                    </GridViewColumn>
                </window:TreeListView.Columns>

            </window:TreeListView>

它的风格如下：

 <Style TargetType="{x:Type window:TreeListView}">
            <!--Set the control template.-->
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="{x:Type window:TreeListView}">
                        <ControlTemplate.Resources>
                            <!--Apply this style to all 'TreeViewItem's.-->
                            <Style TargetType="TreeViewItem" BasedOn="{StaticResource VSTreeViewItem}">
                                <Setter Property="Template" Value="{StaticResource TreeListViewItem}"/>
                                <Setter Property="ScrollViewer.CanContentScroll" Value="True"/>
                                <Setter Property="IsExpanded" Value="True"/>
                                <Setter Property="Foreground" Value="{DynamicResource {x:Static mfcolors:Environment.ToolWindowTextBrushKey}}"/>
                                <Setter Property="Background" Value="{DynamicResource {x:Static mfcolors:Environment.ToolWindowBackgroundBrushKey}}" />
                                <Setter Property="BorderBrush" Value="{DynamicResource {x:Static mfcolors:Environment.ToolWindowBackgroundBrushKey}}" />
                                <EventSetter Event="PreviewMouseDoubleClick" Handler="MainTree_OnPreviewItemDoubleClicked"/>
                                <EventSetter Event="KeyDown" Handler="MainTree_OnItemKeyDown"/>
                                <EventSetter Event="MouseRightButtonDown" Handler="MainTree_OnItemRightButtonDown"/>
                            </Style>
                            <!--Apply this style to all 'TreeListViewExpander's.-->
                            <Style TargetType="window:TreeListViewExpander">
                                <Setter Property="Template" Value="{StaticResource TreeListViewExpander}"/>
                            </Style>
                        </ControlTemplate.Resources>
                        <!--Create a standard border around the 'TreeListView'.-->
                        <Border Background="{TemplateBinding Background}"
                        BorderBrush="{TemplateBinding BorderBrush}"
                        BorderThickness="{TemplateBinding BorderThickness}">
                            <!--ScrollViewer providing horizontal scrolling functionality for both, content and headers.-->
                            <ScrollViewer HorizontalScrollBarVisibility="Auto"
                                  VerticalScrollBarVisibility="Auto"  ScrollViewer.CanContentScroll="True">
                                <!--Grid containing the header row and all the content rows.-->
                                <Grid ScrollViewer.CanContentScroll="True">
                                    <Grid.RowDefinitions>
                                        <!--The header row.-->
                                        <RowDefinition Height="Auto"/>
                                        <!--The content row.-->
                                        <RowDefinition Height="*"/>
                                    </Grid.RowDefinitions>
                                    <!--The header row.-->
                                    <GridViewHeaderRowPresenter Columns="{TemplateBinding Columns}" AllowsColumnReorder="{TemplateBinding AllowsColumnReorder}">
                                    </GridViewHeaderRowPresenter>
                                    <!--ScrollViewer providing vertical scrolling functionality for the content.-->
                                    <ScrollViewer HorizontalScrollBarVisibility="Disabled"
                                          VerticalScrollBarVisibility="Auto"
                                          Grid.Row="1"  ScrollViewer.CanContentScroll="True">
                                        <!--ItemsPresenter containing the content.-->
                                        <ItemsPresenter/>
                                    </ScrollViewer>
                                </Grid>
                            </ScrollViewer>
                        </Border>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>

有人能发现我失踪的东西吗？例如，是否有必要将滚动条/网格包裹起来？ 谢谢！