wpf 将 DataGridColumn 的 Width 属性绑定到父 DataGrid 的 ActualWidth

Binding the Width Property of a DataGridColumn to the ActualWidth of the parent DataGrid

提问by Julius

I tried to solve my previous questionwith manually binding the Widthproperty of the DataGridTextColumnhere is the first Version of my XAML Code.

我试图通过手动绑定这里的属性来解决我之前的问题，这是我的 XAML 代码的第一个版本。WidthDataGridTextColumn

   <DataGrid AutoGenerateColumns="False" Background="White" ItemsSource="{Binding Items, Mode=OneWay}" 
              HorizontalGridLinesBrush="Silver" VerticalGridLinesBrush="Silver"
              Margin="332,10,10,10" CanUserAddRows="False" CanUserDeleteRows="False"
              x:Name="myDataGrid" ColumnWidth="*">
        <DataGrid.Columns>
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, RelativeSource={RelativeSource AncestorType=DataGrid}}" IsReadOnly="True" Header="Column1" Binding="{Binding Value1, Mode=OneWay}" />
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, RelativeSource={RelativeSource AncestorType=DataGrid}}" IsReadOnly="True" Header="Column2" Binding="{Binding Value2, Mode=OneWay}"/>
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, RelativeSource={RelativeSource AncestorType=DataGrid}}" IsReadOnly="True" Header="Column3" Binding="{Binding Value3, Mode=OneWay}"/>
        </DataGrid.Columns>
    </DataGrid>

After a little research i found this postthat seems to provide the answer to my problem and i updated my DataGridcode.

经过一些研究，我发现这篇文章似乎为我的问题提供了答案，我更新了我的DataGrid代码。

   <DataGrid AutoGenerateColumns="False" Background="White" ItemsSource="{Binding Items, Mode=OneWay}" 
              HorizontalGridLinesBrush="Silver" VerticalGridLinesBrush="Silver"
              Margin="332,10,10,10" CanUserAddRows="False" CanUserDeleteRows="False"
              x:Name="myDataGrid" ColumnWidth="*">
        <DataGrid.Columns>
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, Source={x:Reference Name=myDataGrid}}" IsReadOnly="True" Header="Column1" Binding="{Binding Value1, Mode=OneWay}" />
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, Source={x:Reference Name=myDataGrid}}" IsReadOnly="True" Header="Column2" Binding="{Binding Value2, Mode=OneWay}"/>
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, Source={x:Reference Name=myDataGrid}}" IsReadOnly="True" Header="Column3" Binding="{Binding Value3, Mode=OneWay}"/>
        </DataGrid.Columns>
    </DataGrid>

but now im getting this XamlParseException

但现在我得到这个 XamlParseException

Cannot call MarkupExtension.ProvideValue because of a cyclical dependency. Properties inside a 
MarkupExtension cannot reference objects that reference the result of the MarkupExtension. 
The affected MarkupExtensions are:
'System.Windows.Data.Binding' Line number '37' and line position '37'.
'System.Windows.Data.Binding' Line number '38' and line position '37'.
'System.Windows.Data.Binding' Line number '39' and line position '37'.

So how can i bind the Widthproperty of a DataGridColumnto the ActualWidthproperty of its parent DataGrid

那么如何将 a 的Width属性绑定DataGridColumn到ActualWidth其父级的属性DataGrid

回答by Paul Ramsperger

Had the same issue and found out that using x:Reference you cannot refer to any container of the object you are using it from. Nasty hack, but I'd imagine if you created some other control (TextBlock) and bound it's width to the DataGridActualWidthand THEN used x:Reference on that TextBlockit would avoid the cyclical reference

遇到了同样的问题，发现使用 x:Reference 不能引用您正在使用它的对象的任何容器。讨厌的黑客，但我想如果你创建了一些其他控件（TextBlock）并将它的宽度绑定到DataGridActualWidth然后使用 x:Reference 上TextBlock它会避免循环引用

<TextBlock x:Name="TextBlock1" Width="{Binding ElementName=myDataGrid, Path=ActualWidth}" />
<DataGrid AutoGenerateColumns="False" Background="White" ItemsSource="{Binding Items, Mode=OneWay}" 
          HorizontalGridLinesBrush="Silver" VerticalGridLinesBrush="Silver"
          Margin="332,10,10,10" CanUserAddRows="False" CanUserDeleteRows="False"
          x:Name="myDataGrid" ColumnWidth="*">
        <DataGrid.Columns>
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, Source={x:Reference Name=TextBlock1}}" IsReadOnly="True" Header="Column1" Binding="{Binding Value1, Mode=OneWay}" />
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, Source={x:Reference Name=TextBlock1}}" IsReadOnly="True" Header="Column2" Binding="{Binding Value2, Mode=OneWay}"/>
            <DataGridTextColumn Width="{Binding Path=ActualWidth, Converter={StaticResource ResourceKey=WidthValueConverter}, Source={x:Reference Name=TextBlock1}}" IsReadOnly="True" Header="Column3" Binding="{Binding Value3, Mode=OneWay}"/>
        </DataGrid.Columns>
</DataGrid>