wpf中treeview的滚动条显示问题

悬赏园豆：50 [已解决问题] 解决于 2014-09-25 14:45

<TabItem Header="目录查看" Margin="0,0,-4,-3">
                <TreeView x:Name="treeView"  Canvas.Top="71" Canvas.Left="10" BorderThickness="0" RenderTransformOrigin="0.516,0.512" Margin="10,11,7,-3" ScrollViewer.HorizontalScrollBarVisibility="Visible" ScrollViewer.VerticalScrollBarVisibility="Visible" VerticalContentAlignment="Stretch" HorizontalContentAlignment="Stretch" ScrollViewer.CanContentScroll="True"  >
                    <TreeView.ItemContainerStyle>
                        <Style TargetType="{x:Type TreeViewItem}">
                            <EventSetter Event="TreeViewItem.MouseDoubleClick" Handler="TreeViewItem_Preview"/>
                            <EventSetter Event="TreeViewItem.PreviewMouseRightButtonDown" Handler="TreeViewItem_PreviewMouseRightButtonDown"/>
                        </Style>
                    </TreeView.ItemContainerStyle>
                    <TreeView.ContextMenu>
                        <ContextMenu Name="popMenu" StaysOpen="True" >
                            <MenuItem  Header="移动到分类" Click="opencategory"></MenuItem>
                            <MenuItem Header="打开所在目录" Click="opendir"></MenuItem>
                            <MenuItem Header="删除目录/模型" Click="deletedir"></MenuItem>
                            <MenuItem Header="刷新" Click="refreshdir"></MenuItem>
                        </ContextMenu>
                    </TreeView.ContextMenu>
                </TreeView>
            </TabItem>