WPF Datagrid.Row AlternationIndex MultiTrigger属性和视图模型

Question

我想知道为什么这个不起作用：

<DataGrid AlternationCount="2"...

<DataGrid.RowStyle>
   <Style TargetType="{x:Type DataGridRow}">
      <Style.Triggers>
         <MultiTrigger>
           <MultiTrigger.Conditions>
              <Condition Binding="{Binding AlternationIndex, RelativeSource={RelativeSource Self}}" Value="0" />
              <Condition Binding="{Binding IsTicket}" Value="False" />
           </MultiTrigger.Conditions>
           <MultiTrigger.Setters>
              <Setter Property="Background" Value="White" />
            </MultiTrigger.Setters>
         </MultiTrigger>
      </Style.Triggers>
   </Style>
</DataGrid.RowStyle>

此代码抛出InvalidOperationException“必须具有‘Property’的非空值”。IsTiket是Datagrid绑定到的Datacontext的属性

这段代码可以工作，但我需要MultiTrigger：

<DataGrid.RowStyle>
    <Style TargetType="{x:Type DataGridRow}">
        <Style.Triggers>
            <Trigger Property="AlternationIndex" Value="0">
                <Setter Property="Background" Value="White" />
            </Trigger>
            <DataTrigger Binding="{Binding IsTicket}" Value="True">
               <DataTrigger.Setters>
                  <Setter Property="Background" Value="Gold" />
               </DataTrigger.Setters>
             </DataTrigger>
        </Style.Triggers>
    </Style>
 </DataGrid.RowStyle>

解决方案:语法错误，我必须使用MultiDataTrigger：

<DataGrid.RowStyle>
   <Style TargetType="{x:Type DataGridRow}">
      <Style.Triggers>
         <MultiDataTrigger>
           <MultiDataTrigger.Conditions>
              <Condition Binding="{Binding AlternationIndex, RelativeSource={RelativeSource Self}}" Value="0" />
              <Condition Binding="{Binding IsTicket}" Value="False" />
           </MultiDataTrigger.Conditions>
           <MultiDataTrigger.Setters>
              <Setter Property="Background" Value="White" />
            </MultiDataTrigger.Setters>
         </MultiDataTrigger>
      </Style.Triggers>
   </Style>
</DataGrid.RowStyle>

Answer 1

您使用的是多触发器，而不是多数据触发器。试一试

<Style TargetType="{x:Type DataGridRow}">
    <Style.Triggers>
        <MultiDataTrigger>
            <MultiDataTrigger.Conditions>
                <Condition Binding="{Binding Path=AlternationIndex, RelativeSource={RelativeSource Self}}" Value="0" />
                <Condition Binding="{Binding IsTicket}" Value="False" />
            </MultiDataTrigger.Conditions>
            <Setter Property="Background" Value="White" />
        </MultiDataTrigger>
    </Style.Triggers>
</Style>