ContentTemplate绑定问题

本文关键字：问题 绑定 ContentTemplate | 更新日期: 2023-09-27 18:06:31

我在我的应用程序中有来自WPF工具包的DataGrid控件。我需要替换用于调优TextBlock的单元格的默认TextBlock。xml代码看起来像:

<Window.Resources>
    <Style x:Key="cellStyle" TargetType="{x:Type tk:DataGridCell}">
        <Setter Property="ContentTemplate">
            <Setter.Value>
                <DataTemplate>
                    <TextBlock Background="Yellow" />
                </DataTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</Window.Resources>
<Grid>
    <tk:DataGrid
        ItemsSource="{Binding Path=Products}"
        CellStyle="{StaticResource cellStyle}"
        AutoGenerateColumns="False">
        <tk:DataGrid.Columns>
            <tk:DataGridTextColumn
                Header="Id"
                Binding="{Binding Path=Id}"/>
            <tk:DataGridTextColumn
                Header="Product"
                Binding="{Binding Path=Name}"/>
        </tk:DataGrid.Columns>
    </tk:DataGrid>
</Grid>

TextBlock替换后，所有数据绑定丢失，所有单元格为空。添加属性Text="{Binding}"到新的TextBlock没有帮助。在这种情况下，所有单元格都包含DataGridTestApp.Product类型的名称。TextBlock的正确绑定表达式是什么?

注:以防万一:MainWindowViewModel

的代码
internal sealed class MainWindowViewModel
{
    public MainWindowViewModel()
    {
        _products = new ObservableCollection<Product>()
        {
            new Product(1, "ProductName1"),
            new Product(2, "ProductName2"),
            new Product(3, "ProductName3"),
            new Product(4, "ProductName4"),
            new Product(5, "ProductName5"),
        };
    }
    public ObservableCollection<Product> Products
    {
        get { return _products; }
    }
    private ObservableCollection<Product> _products;
}

ContentTemplate绑定问题

如果查看Toolkit的源代码，您将发现数据网格单元格的现有样式(它使用内容表示器来显示列)

  <Style x:Key="{x:Type dg:DataGridCell}" TargetType="{x:Type dg:DataGridCell}">
    <Setter Property="Background" Value="Transparent" />
    <Setter Property="BorderBrush" Value="Transparent" />
    <Setter Property="BorderThickness" Value="1" />
    <Setter Property="Template">
      <Setter.Value>
        <ControlTemplate TargetType="{x:Type dg:DataGridCell}">
          <Border Background="{TemplateBinding Background}" 
                  BorderBrush="{TemplateBinding BorderBrush}"  
                  BorderThickness="{TemplateBinding BorderThickness}" 
                  SnapsToDevicePixels="True">
            <ContentPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
          </Border>
        </ControlTemplate>
      </Setter.Value>
    </Setter>
    <Style.Triggers>
      <Trigger Property="IsSelected" Value="True">
        <Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
        <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}" />
        <Setter Property="BorderBrush" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
      </Trigger>
      <Trigger Property="IsKeyboardFocusWithin" Value="True">
        <Setter Property="BorderBrush" Value="{DynamicResource {x:Static dg:DataGrid.FocusBorderBrushKey}}" />
      </Trigger>
    </Style.Triggers>
  </Style>

要得到黄色背景，我只需替换

    <Setter Property="Background" Value="Transparent" />


    <Setter Property="Background" Value="Yellow" />

如果你急于覆盖TextBlock内部，那么使用上面的模板，但只在Border

<Border.Resources>
  <Style TargetType="{x:Type TextBlock}">
    <Setter Property="Margin" Value="0,5" />
    <Setter Property="Background" Value="Yellow" />
  </Style>
</Border.Resources>

TextBlock的数据上下文是一个Product。如果是要显示的产品名称，则使用以下命令:

<Window.Resources>
    <Style x:Key="cellStyle" TargetType="{x:Type tk:DataGridCell}">
        <Setter Property="ContentTemplate">
            <Setter.Value>
                <DataTemplate>
                    <TextBlock Background="Yellow" Text="{Binding Name}" />
                </DataTemplate>
            </Setter.Value>
        </Setter>
    </Style>
</Window.Resources>

不幸的是，如果您覆盖模板，您将丢失在DataGridTextColumn中设置的任何绑定。

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