如何根据XAML中的窗口或屏幕大小设置网格列MaxWidth

<Grid>
    <Grid.ColumnDefinitions>
       <ColumnDefinition Width="*" />
       <ColumnDefinition Width="Auto" />
       <ColumnDefinition Width="*" />
    </Grid.ColumnDefinitions>
    <TextBlock Grid.Column="0" Text="Column 1" />
    <TextBlock Grid.Column="1" Text="Column 2" />
    <TextBlock Grid.Column="2" Text="Column 3" />
</Grid>

<Grid>
    <Grid.ColumnDefinitions>
       <ColumnDefinition Width="{Binding Source={x:Static SystemParameters.PrimaryScreenWidth}, Converter={StaticResource GridColumnWidthConverter}}" />
       <ColumnDefinition Width="Auto" />
       <ColumnDefinition Width="{Binding Source={x:Static SystemParameters.PrimaryScreenWidth}, Converter={StaticResource GridColumnWidthConverter}}" />
    </Grid.ColumnDefinitions>
    <TextBlock Grid.Column="0" Text="Column 1" />
    <TextBlock Grid.Column="1" Text="Column 2" />
    <TextBlock Grid.Column="2" Text="Column 3" />
</Grid>

public class GridColumnWidthConverter : IValueConverter
{
    public object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
        double screenWidth = (double)value;
        double maxWidth = screenWidth / 3;
        return new GridLength(maxWidth, GridUnitType.Pixel);
    }

    public object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
        throw new NotImplementedException();
    }
}