Question

我有一个datagrid，它有几个静态和更动态生成的coloumns。使用多值转换器成功调整动态添加的coloumns单元的背景图像。现在我需要向这些单元格添加内容，而不仅仅是改变它们的背景。我希望使用多值转换器来实现这种目的，但它没有。在调试器中运行MultiValueConverter，它返回一个字符串，但单元格保持为空。

请参阅代码，其中背景设置正在运行但内容设置没有。除了gridCellBgConverter返回Brush之外，它们必须是相同的代码，gridCellContentConverter返回字符串。

<DataGrid DockPanel.Dock="Top" Name="main_dg" HorizontalAlignment="Stretch" HorizontalScrollBarVisibility="Hidden" Margin="3"
AutoGenerateColumns="False" SelectionMode="Single" SelectionUnit="Cell" 
SelectedCellsChanged="main_dg_SelectedCellsChanged" CanUserReorderColumns="False" 
CanUserAddRows="False" CellEditEnding="main_dg_CellEditEnding" KeyUp="main_dg_KeyUp" 
FontSize="14" FontWeight="Normal" FontStretch="Normal" SnapsToDevicePixels="True" TextOptions.TextFormattingMode="Display" RenderOptions.EdgeMode="Aliased">
<DataGrid.Resources>
    <Style x:Key="errorStyle" TargetType="{x:Type TextBox}">
        <Setter Property="Padding" Value="-2"/>
        <Style.Triggers>
            <Trigger Property="Validation.HasError" Value="True">
                <Setter Property="Background" Value="Red"/>
                <Setter Property="ToolTip" Value="{Binding RelativeSource={RelativeSource Self}, Path=(Validation.Errors)[0].ErrorContent}"/>
            </Trigger>
        </Style.Triggers>
    </Style>
</DataGrid.Resources>
    <DataGrid.CellStyle>
        <Style TargetType="DataGridCell">
            <Setter Property="Background">
                <Setter.Value>
                    <MultiBinding Converter="{StaticResource gridCellBgConverter}" UpdateSourceTrigger="PropertyChanged">
                        <MultiBinding.Bindings>
                            <Binding RelativeSource="{RelativeSource Self}"></Binding>
                            <Binding Path="." UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.SelectedStationIndex" UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.TrainOnTrackElementId" UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.LastStationCountDownChanged" UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.SelectedStationDelay" UpdateSourceTrigger="PropertyChanged"></Binding>
                        </MultiBinding.Bindings>
                    </MultiBinding>
                </Setter.Value>
            </Setter>
            <Setter Property="Content">
                <Setter.Value>
                    <MultiBinding Converter="{StaticResource gridCellContentConverter}" UpdateSourceTrigger="PropertyChanged">
                        <MultiBinding.Bindings>
                            <Binding RelativeSource="{RelativeSource Self}"></Binding>
                            <Binding Path="." UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.SelectedStationIndex" UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.TrainOnTrackElementId" UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.LastStationCountDownChanged" UpdateSourceTrigger="PropertyChanged"></Binding>
                            <Binding Path="TrainToAnnounceViewModel.SelectedStationDelay" UpdateSourceTrigger="PropertyChanged"></Binding>
                        </MultiBinding.Bindings>
                    </MultiBinding>
                </Setter.Value>
            </Setter>                                            
        </Style>
    </DataGrid.CellStyle>

WPF的固有属性是否无法通过Style和ValueConverter设置内容？你知道如何解决这个问题吗？

提前致谢： Ferenc的

解决方案

在AngelWPF的帮助下，我能够解决我的问题：

动态创建的coloumns类型是DataGridTemplateColoumn

样式设定器是：

<Setter Property="ContentTemplate">
<Setter.Value>
    <DataTemplate>
        <StackPanel Orientation="Horizontal">
            <TextBlock>
                <TextBlock.Text>                                                   
                <MultiBinding Converter="{StaticResource gridCellContentConverter}" UpdateSourceTrigger="PropertyChanged">
                    <MultiBinding.Bindings>
                        <Binding RelativeSource="{RelativeSource Self}"></Binding>
                        <Binding Path="." UpdateSourceTrigger="PropertyChanged"></Binding>
                        <Binding Path="TrainToAnnounceViewModel.SelectedStationIndex" UpdateSourceTrigger="PropertyChanged"></Binding>
                        <Binding Path="TrainToAnnounceViewModel.TrainOnTrackElementId" UpdateSourceTrigger="PropertyChanged"></Binding>
                        <Binding Path="TrainToAnnounceViewModel.LastStationCountDownChanged" UpdateSourceTrigger="PropertyChanged"></Binding>
                        <Binding Path="TrainToAnnounceViewModel.SelectedStationDelay" UpdateSourceTrigger="PropertyChanged"></Binding>
                    </MultiBinding.Bindings>
                </MultiBinding>
            </TextBlock.Text>
            </TextBlock>
        </StackPanel>
    </DataTemplate>
</Setter.Value>

并在MultiValueConverter而不是

public object Convert(object[] values,
       Type targetType, object parameter,
       CultureInfo culture) {
         var cell = (DataGridCell)values[0];

我必须使用

public object Convert(object[] values,
       Type targetType, object parameter,
       CultureInfo culture) {
          var textBlock = (TextBlock)values[0];
          var cell = (DataGridCell)((ContentPresenter)textBlock.TemplatedParent).TemplatedParent

访问原始单元格。我毫不怀疑有更好的方法可以做到这一点，但似乎有效：）

Answer 1

假设您的数据网格是只读的（不可编辑），可以按照以下方式实现。

（以下代码未经过测试）

      <Style TargetType="{x:Type DataGridCell}">
          <Setter Property="Template">
              <Setter.Value>
                  <ControlTemplate TargetType="{x:Type DataGridCell}">
                      <Border Background="Transparent" 
                    BorderBrush="{TemplateBinding BorderBrush}"  
                    BorderThickness="0" 
                    SnapsToDevicePixels="True">
                          <TextBlock>
                              <TextBlock.Text>
                                <!-- Your MultiBinding Here -->
                              </TextBlock.Text>
                          </TextBlock> 
                      </Border>
                  </ControlTemplate>
              </Setter.Value>
          </Setter>
      </Style>

关于这种方法的注意事项是你在这方面失去了许多单元级功能，例如验证，编辑模式，背景颜色，鼠标悬停，选择颜色等......

我仍然建议使用DataGridTemplate列和CellTemplate属性。

WPF：可以通过MultiValueConverter设置DataGridCell的内容吗？

1 个答案: