Datagrid: Can I set a tranparency level for column background color?

Question

Hi all,
I have a datagrid with background colors set using triggers. This works. I would like to set a column background color but I don't want to make the color solid because it will block the row color. Is there a way to set the column background color transparency
to 50% (or less) so that I can still see (or blend) with the row background color? I can set the "background" property of the column to a value of "transparent" but this makes no sense without a color.
Thanks
<DataGrid.RowStyle>
<Style TargetType="DataGridRow">
<Style.Triggers>
<DataTrigger Binding="{Binding col_oPutorCall}" Value="call">
<Setter Property="Background" Value="Cornsilk"/>
</DataTrigger>
<DataTrigger Binding="{Binding col_oPutorCall}" Value="put">
<Setter Property="Background" Value="BlanchedAlmond"/>
</DataTrigger>
<DataTrigger Binding="{Binding col_rowColor}" Value="false">
<Setter Property="Background" Value="LightGreen"/>
</DataTrigger>
</Style.Triggers>
</Style>
</DataGrid.RowStyle>
<DataGridTextColumn Binding="{Binding col_oBid, StringFormat=F2}" FontFamily="Arial" FontWeight="Bold" FontSize="12" Header="oB" >
<DataGridTextColumn.CellStyle>
<Style TargetType="DataGridCell">
<Setter Property="Background" Value= "Transparent" />
<Setter Property="Background" Value= "AliceBlue" />
</Style>
</DataGridTextColumn.CellStyle>
</DataGridTextColumn>

Answer 1

Background is a brush.
You can define a brush with an opacity in a resourcedictionary merged in app.xaml or in your window.resources ( etc ).
<Grid.Resources>
<SolidColorBrush x:Key="TransparentIshBrush" Color="Red" Opacity=".3" />
</Grid.Resources>
I should think you can then do:
<DataGridTextColumn Binding="{Binding col_oBid, StringFormat=F2}" FontFamily="Arial" FontWeight="Bold" FontSize="12" Header="oB" >
<DataGridTextColumn.CellStyle>
<Style TargetType="DataGridCell">
<Setter Property="Background" Value="{StaticResource TransparentIshBrush}" />
</Style>
</DataGridTextColumn.CellStyle>
</DataGridTextColumn>
The problem with your former piece of code is that setting an opacity on a datagridcell gets everything in it. You would have to do
<Setter Property="(BackGround.Opacity)"
And I'm rather doubtful that would work anyhow.
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