绑定到WPF中的嵌套控件

Question

我使用了一个自定义数据网格控件，该控件将TextBox添加到列标题中以进行过滤。不幸的是，当我尝试将DataGridRow的Visiblilty属性绑定到TextBox的Text属性（称为filterTextBox）时，我遇到了一个问题。参见下面的代码。在转换器方法“ SearchColumnToVisibilityConverter”中接收的对象的值为“ DependencyProperty.UnsetValue”。

<ControlTemplate TargetType="{x:Type local:SimpuDataGrid}">
                    <Border Background="{TemplateBinding Background}"
                            BorderBrush="{TemplateBinding BorderBrush}"
                            BorderThickness="{TemplateBinding BorderThickness}">                        
                        <StackPanel Orientation="Vertical" DataContext="{TemplateBinding DataContext}">
                            <TextBox Width="200" Margin="2" HorizontalAlignment="Left" x:Name="txtFullTextSearch" 
                                     Visibility="{TemplateBinding EnableFullTextSearch, 
                                Converter={StaticResource BooleanToVisibilityConverter}}" />
                            <DataGrid x:Name="simpuGrid" 
                                      ItemsSource="{TemplateBinding ItemsSource}" CanUserAddRows="{TemplateBinding CanUserAddRows}"
                                      CanUserDeleteRows="{TemplateBinding CanUserDeleteRows}" 
                                      AutoGenerateColumns="{TemplateBinding AutoGenerateColumns}">
                                <DataGrid.Resources>

                                    <!--Custom Column Header template to show extra elements in the header-->
                                    <Style TargetType="{x:Type DataGridColumnHeader}">
                                        <Setter Property="Template">
                                            <Setter.Value>
                                                <ControlTemplate TargetType="{x:Type DataGridColumnHeader}">
                                                    <!--Let's keep the top section grid to contain the DataGridHeaderBorder, and left+right thumbs.-->
                                                    <Grid x:Name="fullHeader" Background="{StaticResource normalBrushBack}">

                                                        <!--Here is the theme based DataGridHeaderBorder. I've used Aero here.-->
                                                        <aero:DataGridHeaderBorder x:Name='HeaderBorder' SortDirection="{TemplateBinding SortDirection}" IsHovered="{TemplateBinding IsMouseOver}" IsPressed="{TemplateBinding IsPressed}" IsClickable="{TemplateBinding CanUserSort}" BorderThickness="0,0,1,1" BorderBrush="{TemplateBinding Foreground}"  Background="Transparent" SeparatorVisibility="{TemplateBinding SeparatorVisibility}" SeparatorBrush="#FFC9CACA">
                                                            <!--We will put 3 elements inside the border: Content of header, a drop down button, and a sort order indicator.-->
                                                            <Grid Margin="0,0,0,0">
                                                                <Grid.RowDefinitions>
                                                                    <!--For ContentPresenter-->
                                                                    <RowDefinition Height="*" />
                                                                    <!--For drop down button-->
                                                                    <RowDefinition Height="*" />
                                                                </Grid.RowDefinitions>
                                                                <Grid.ColumnDefinitions>
                                                                    <!--For ContentPresenter-->
                                                                    <ColumnDefinition Width="*" />
                                                                    <!--For sort order indicator-->
                                                                    <ColumnDefinition Width="12" />
                                                                </Grid.ColumnDefinitions>
                                                                <!--Content of the header.-->
                                                                <ContentPresenter Grid.Row="0" Grid.Column="0" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"  HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"  Margin="{TemplateBinding Padding}" Cursor="{TemplateBinding Cursor}" >
                                                                    <ContentPresenter.Content>
                                                                        <MultiBinding Converter="{StaticResource headerConverter}">
                                                                            <MultiBinding.Bindings>
                                                                                <Binding ElementName="filterTextBox" Path="Text" />
                                                                                <Binding RelativeSource="{RelativeSource TemplatedParent}" Path="Content" />
                                                                            </MultiBinding.Bindings>
                                                                        </MultiBinding>
                                                                    </ContentPresenter.Content>
                                                                </ContentPresenter>
                                                                <!--A textbox filter-->
                                                                <TextBox x:Name="filterTextBox" Background="White" Grid.Row="1" Grid.ColumnSpan="2" />
                                                                <!--A sort order arrow icon.-->
                                                                <Path x:Name="SortArrow" Grid.Row="0" Grid.Column="1" HorizontalAlignment="Right" VerticalAlignment="Center"  Width="8" RenderTransformOrigin=".5,.5" Visibility="Visible" Fill="{TemplateBinding Foreground}" Stretch="Uniform"  Data="F1 M -5.215,6.099L 5.215,6.099L 0,0L -5.215,6.099 Z" />
                                                            </Grid>
                                                        </aero:DataGridHeaderBorder>
                                                        <Thumb x:Name="PART_LeftHeaderGripper" HorizontalAlignment="Left" Style="{StaticResource ColumnHeaderGripperStyle}" />
                                                        <Thumb x:Name="PART_RightHeaderGripper" HorizontalAlignment="Right" Style="{StaticResource ColumnHeaderGripperStyle}" />
                                                    </Grid>
                                                    <ControlTemplate.Triggers>
                                                        <Trigger Property="SortDirection" Value="Descending">
                                                            <Setter TargetName="SortArrow" Property="RenderTransform">
                                                                <Setter.Value>
                                                                    <RotateTransform Angle="180" />
                                                                </Setter.Value>
                                                            </Setter>
                                                        </Trigger>

                                                        <Trigger Property='IsMouseOver' SourceName="fullHeader" Value='True'>
                                                            <Trigger.EnterActions>
                                                                <BeginStoryboard>
                                                                    <Storyboard>
                                                                        <DoubleAnimation BeginTime="00:00:00" Duration="00:00:00.20000"
                                                                     Storyboard.TargetName="HoverRectangle"
                                                                     Storyboard.TargetProperty="(UIElement.Opacity)"
                                                                     To='1.0' />
                                                                    </Storyboard>
                                                                </BeginStoryboard>
                                                            </Trigger.EnterActions>
                                                            <Trigger.ExitActions>
                                                                <BeginStoryboard>
                                                                    <Storyboard>
                                                                        <DoubleAnimation BeginTime="00:00:00" Duration="00:00:00.20000"
                                                                     Storyboard.TargetName="HoverRectangle"
                                                                     Storyboard.TargetProperty="(UIElement.Opacity)"
                                                                     To='0' />
                                                                    </Storyboard>
                                                                </BeginStoryboard>
                                                            </Trigger.ExitActions>
                                                        </Trigger>
                                                    </ControlTemplate.Triggers>
                                                </ControlTemplate>
                                            </Setter.Value>
                                        </Setter>
                                    </Style>
                                    <!--End of custom DataGridColumnHeader template-->
                                </DataGrid.Resources>
                                <DataGrid.ItemContainerStyle>
                                    <Style TargetType="{x:Type DataGridRow}">
                                        <Setter Property="Visibility">
                                            <Setter.Value>
                                                <MultiBinding Converter="{StaticResource SearchColumnToVisibilityConverter}">
                                                    <Binding ElementName="filterTextBox" Path="Text"/>
                                                    <Binding BindsDirectlyToSource="True"/>
                                                </MultiBinding>
                                            </Setter.Value>
                                        </Setter>
                                    </Style>
                                </DataGrid.ItemContainerStyle>
                            </DataGrid>
                        </StackPanel>                        
                    </Border>
                </ControlTemplate>

我希望有人能帮助我！

谢谢