Silverlight - Stop highlights on a listbox

Question

I've got a silverlight listbox and I want to remove the colour change highlight that occurs when the user selects an item in the listbox.

By default when an item is selected it highlights the item a sort of light blue color.

How can I stop this from occuring?

As an side question, how do I customise this to any arbitary colour?

Thanks.

Answer 1

You can do this by customizing the existing Control Template for a ListBox Item. The easy way to do this is to fire up Expression Blend, right click a ListBoxItem, go to Edit Control Parts (Template) and select Edit a Copy... then customize the Fill color of the fillColor and fillColor2 rectangles as required.

The Xaml below sets the ListBoxItem mouse-over color to be transparent and the selected color to be bright green but you can customize this to your needs:

<UserControl x:Class="SilverlightApplication2.Page"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:vsm="clr-namespace:System.Windows;assembly=System.Windows"
    Width="400" Height="300" Background="#FF000000">
  <UserControl.Resources>
    <Style x:Key="ListBoxItemStyleTransparent" TargetType="ListBoxItem">
      <Setter Property="Padding" Value="3"/>
      <Setter Property="HorizontalContentAlignment" Value="Left"/>
      <Setter Property="VerticalContentAlignment" Value="Top"/>
      <Setter Property="Background" Value="Transparent"/>
      <Setter Property="BorderThickness" Value="1"/>
      <Setter Property="TabNavigation" Value="Local"/>
      <Setter Property="Template">
        <Setter.Value>
          <ControlTemplate TargetType="ListBoxItem">
            <Grid Background="{TemplateBinding Background}">
              <vsm:VisualStateManager.VisualStateGroups>
                <vsm:VisualStateGroup x:Name="CommonStates">
                  <vsm:VisualState x:Name="Normal"/>
                  <vsm:VisualState x:Name="MouseOver">
                    <Storyboard>
                      <DoubleAnimationUsingKeyFrames Storyboard.TargetName="fillColor" Storyboard.TargetProperty="Opacity">
                        <SplineDoubleKeyFrame KeyTime="0" Value=".35"/>
                      </DoubleAnimationUsingKeyFrames>
                    </Storyboard>
                  </vsm:VisualState>
                  <vsm:VisualState x:Name="Disabled">
                    <Storyboard>
                      <DoubleAnimationUsingKeyFrames Storyboard.TargetName="contentPresenter" Storyboard.TargetProperty="Opacity">
                        <SplineDoubleKeyFrame KeyTime="0" Value=".55"/>
                      </DoubleAnimationUsingKeyFrames>
                    </Storyboard>
                  </vsm:VisualState>
                </vsm:VisualStateGroup>
                <vsm:VisualStateGroup x:Name="SelectionStates">
                  <vsm:VisualState x:Name="Unselected"/>
                  <vsm:VisualState x:Name="Selected">
                    <Storyboard>
                      <DoubleAnimationUsingKeyFrames Storyboard.TargetName="fillColor2" Storyboard.TargetProperty="Opacity">
                        <SplineDoubleKeyFrame KeyTime="0" Value=".75"/>
                      </DoubleAnimationUsingKeyFrames>
                    </Storyboard>
                  </vsm:VisualState>
                </vsm:VisualStateGroup>
                <vsm:VisualStateGroup x:Name="FocusStates">
                  <vsm:VisualState x:Name="Focused">
                    <Storyboard>
                      <ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetName="FocusVisualElement" Storyboard.TargetProperty="Visibility">
                        <DiscreteObjectKeyFrame KeyTime="0">
                          <DiscreteObjectKeyFrame.Value>
                            <Visibility>Visible</Visibility>
                          </DiscreteObjectKeyFrame.Value>
                        </DiscreteObjectKeyFrame>
                      </ObjectAnimationUsingKeyFrames>
                    </Storyboard>
                  </vsm:VisualState>
                  <vsm:VisualState x:Name="Unfocused"/>
                </vsm:VisualStateGroup>
              </vsm:VisualStateManager.VisualStateGroups>
              <Rectangle x:Name="fillColor" IsHitTestVisible="False" Opacity="0" RadiusX="1" RadiusY="1" Fill="Transparent"/>
              <Rectangle x:Name="fillColor2" IsHitTestVisible="False" Opacity="0" Fill="#FF00FF00" RadiusX="1" RadiusY="1"/>
              <ContentPresenter HorizontalAlignment="Left" Margin="{TemplateBinding Padding}" x:Name="contentPresenter" Content="{TemplateBinding Content}" ContentTemplate="{TemplateBinding ContentTemplate}"/>
              <Rectangle x:Name="FocusVisualElement" Visibility="Collapsed" Stroke="#FF6DBDD1" StrokeThickness="1" RadiusX="1" RadiusY="1"/>
            </Grid>
          </ControlTemplate>
        </Setter.Value>
      </Setter>
    </Style>
  </UserControl.Resources>
  <Grid x:Name="LayoutRoot" Background="White">
    <ListBox x:Name="ListBoxTest">
      <ListBoxItem Content="Some String" Style="{StaticResource ListBoxItemStyleTransparent}" />
    </ListBox>
  </Grid>
</UserControl>

The fillColor Rectangle specifies the color to use when the user mouses-over a ListBoxItem. In the code above I have set this to be Transparent so no color will appear when you mouse over the ListBoxItem.

The fillColor2 specifies the color to use when a ListBoxItem is selected. In the code above I've specified #FF00FF00 so the color will be bright green when a ListBoxItem is selected.

In your situation you would set the Fill property of the fillColor2 Rectangle to be Transparent to simulate no color when the user selects an item.