TreeView标签导航

Question

我有一个带有Grid的UserControl，它包含一个简单的TreeView。我能够向前导航（Tab），而向后方向（Alt + Tab）不能正常工作。 （它关注我的项目模板中的最后一个按钮）。 你有什么建议吗？

    <TreeView ItemsSource="{Binding myList}"
          KeyboardNavigation.TabNavigation="Continue" TabIndex="4" IsTabStop="False">

  <TreeView.ItemContainerStyle>
    <Style TargetType="{x:Type TreeViewItem}">
      <Setter Property="IsExpanded" Value="True" />
      <Setter Property="KeyboardNavigation.TabNavigation" Value="Continue"/>
    </Style>
  </TreeView.ItemContainerStyle>

  <TreeView.ItemTemplate>
    <HierarchicalDataTemplate ItemsSource="{Binding MySubList}">
      <TextBlock Text="{Binding Name}" FontWeight="Bold"/>

      <HierarchicalDataTemplate.ItemTemplate>
        <HierarchicalDataTemplate>
          <Grid KeyboardNavigation.TabNavigation="Local">

            <Grid.ColumnDefinitions>
              <ColumnDefinition Width="Auto" SharedSizeGroup="Col1"/>
              <ColumnDefinition Width="5"    SharedSizeGroup="Col2"/>
              <ColumnDefinition Width="*"/>
              <ColumnDefinition Width="Auto"/>
            </Grid.ColumnDefinitions>

            <Grid.RowDefinitions>
              <RowDefinition Height="Auto"/>
              <RowDefinition Height="Auto"/>
              <RowDefinition Height="Auto"/>
            </Grid.RowDefinitions>

            <GridSplitter Grid.Column="1" Grid.RowSpan="2147483647" Width="5" HorizontalAlignment="Left" VerticalContentAlignment="Stretch" IsTabStop="False"/>

            <TextBlock Grid.Column="0" Grid.Row="0" Text="Text1"/>
            <TextBox   Grid.Column="2" Grid.Row="0" Text="{Binding Text1, UpdateSourceTrigger=LostFocus}" TabIndex="0"/>
            <Button    Grid.Column="3" Grid.Row="0" Content="..." TabIndex="1"/>
          </Grid>
        </HierarchicalDataTemplate>
      </HierarchicalDataTemplate.ItemTemplate>
    </HierarchicalDataTemplate>
  </TreeView.ItemTemplate>
</TreeView>