How to change part of the datatemplate background - wpf

Question

I have a ListBox, its DateTemplate like this:
<Grid Margin="30,0,0,0" HorizontalAlignment="Left">
<Grid.ColumnDefinitions>
<ColumnDefinition />
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Image Source="{Binding Path=IconSource}"/>
<TextBlock Grid.Column="1" Background="{x:Null}" Text="{Binding Path=DisplayText, Mode=Default}" Foreground="Black"/>
</Grid>
and this is the ItemContainerStyle:
<Style x:Key="Test" TargetType="ListBoxItem">
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListBoxItem">
<Border Name="Border" SnapsToDevicePixels="True">
<ContentPresenter/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="true">
<Setter TargetName="Border" Property="Background" Value="Blue" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
When one ListBoxItem is selected, is it possible not to set the image's background?
Like in Intellisense of VS, the icon of the API doens't have background.

Answer 1

The simplest thing is to put your image inside another Grid, and set the Grid's Background to the background color you would like the image to have - then when you change the Background of the parent Border, the image's parent grid will protect it from the background color change.

Answer 2

I am not completely sure if this is what you meant, but I would recommend to use no data template but instead do all the necessary data binding with the elements of the item container control template. This is possible as the item container and the data template actually share the same data context. In case of a ListBoxItem, this would look like this:
<ControlTemplate x:Key="ListBoxItemTemplate" TargetType="ListBoxItem">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<Image Source="{Binding IconSource}" Height="50" Margin="0,0,5,0"/>
<Border x:Name="Border" VerticalAlignment="Center" Grid.Column="1">
<TextBlock Text="{Binding Name}" />
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="true">
<Setter TargetName="Border" Property="Background" Value="Blue" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
You would reference this template in the ItemsContainerStyle that is set on your ListBox.
In summary: do not use a data template but incorporate it in the ItemContainerStyle. Thus you can leave the background of the Image element untouched.
Hope this helps.