Changing Row/Column Background Color

[Dean]

How can we change the TreeListView populated area background ?

WhenTreeListView background is set to Transparent or some color it does become transparent or changes color but as soon as we populate some rows they all have white background which cannot be changed by changing the background of any of the internal TreeListView elements.

I tried changing background of GridViewCell, GridViewRow, GridViewDataColumn, GridViewRowItem, TreeListViewRow, TreeListCellsPanel and pretty much every other element but the background of populated rows remains white.

Thanks.

[Dilyan Traykov]

Hello,

In order to change the background color of the individual rows, you should create the appropriate style targeting the TreeListViewRow element. You will probably also need to modify the control template of the element in order to achieve the desired look. Here's an example for the Office_Black theme:

<SolidColorBrush x:Key="CustomBackgroundColor" Color="Red" />
<Style TargetType="telerik:TreeListViewRow" BasedOn="{StaticResource TreeListViewRowStyle}">
    <Setter Property="Background" Value="{StaticResource CustomBackgroundColor}" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="telerik:TreeListViewRow">
                <Border BorderThickness="{TemplateBinding BorderThickness}" BorderBrush="{TemplateBinding BorderBrush}">
                    <VisualStateManager.VisualStateGroups>
                        <VisualStateGroup x:Name="FocusStates">
                            <VisualState x:Name="Unfocused"/>
                            <VisualState x:Name="Focused">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="NavigatorIndicator" Storyboard.TargetProperty="Visibility">
                                        <DiscreteObjectKeyFrame KeyTime="00:00:00">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup x:Name="SelectionStates">
                            <VisualState x:Name="Unselected"/>
                            <VisualState x:Name="SelectedUnfocused">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetName="Background_Over" Storyboard.TargetProperty="(UIElement.Visibility)">
                                        <DiscreteObjectKeyFrame KeyTime="0">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background_Over" Storyboard.TargetProperty="BorderBrush">
                                        <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{StaticResource ItemOuterBorder_SelectedUnfocused}"/>
                                    </ObjectAnimationUsingKeyFrames>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="BackgroundInner_Over" Storyboard.TargetProperty="Background">
                                        <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{StaticResource CustomBackgroundColor}"/>
                                    </ObjectAnimationUsingKeyFrames>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="BackgroundInner_Over" Storyboard.TargetProperty="BorderBrush">
                                        <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{StaticResource ItemInnerBorder_SelectedUnfocused}"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup x:Name="CommonStates">
                            <VisualState x:Name="Normal"/>
                            <VisualState x:Name="MouseOver">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetName="Background_Over" Storyboard.TargetProperty="(UIElement.Visibility)">
                                        <DiscreteObjectKeyFrame KeyTime="00:00:00">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                            <VisualState x:Name="Selected">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Duration="0" Storyboard.TargetName="Background_Selected" Storyboard.TargetProperty="(UIElement.Visibility)">
                                        <DiscreteObjectKeyFrame KeyTime="00:00:00">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="NavigatorIndicatorBackground" Storyboard.TargetProperty="Background">
                                        <DiscreteObjectKeyFrame KeyTime="0:0:0" Value="{StaticResource GridView_RowIndicatorCellBackground_Selected}"/>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup x:Name="ValueStates">
                            <VisualState x:Name="RowValid"/>
                            <VisualState x:Name="RowInvalid">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background_Invalid" Storyboard.TargetProperty="(UIElement.Visibility)">
                                        <DiscreteObjectKeyFrame KeyTime="00:00:00">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="ErrorIndicator" Storyboard.TargetProperty="Visibility">
                                        <DiscreteObjectKeyFrame KeyTime="00:00:00">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                        <VisualStateGroup x:Name="EditStates">
                            <VisualState x:Name="ReadOnlyMode"/>
                            <VisualState x:Name="EditMode">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="EditIndicator" Storyboard.TargetProperty="Visibility">
                                        <DiscreteObjectKeyFrame KeyTime="0">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                            <VisualState x:Name="InvalidEditMode">
                                <Storyboard>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="Background_Invalid" Storyboard.TargetProperty="(UIElement.Visibility)">
                                        <DiscreteObjectKeyFrame KeyTime="0">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                    <ObjectAnimationUsingKeyFrames Storyboard.TargetName="InvalidEditableIndicator" Storyboard.TargetProperty="Visibility">
                                        <DiscreteObjectKeyFrame KeyTime="0">
                                            <DiscreteObjectKeyFrame.Value>
                                                <Visibility>Visible</Visibility>
                                            </DiscreteObjectKeyFrame.Value>
                                        </DiscreteObjectKeyFrame>
                                    </ObjectAnimationUsingKeyFrames>
                                </Storyboard>
                            </VisualState>
                        </VisualStateGroup>
                    </VisualStateManager.VisualStateGroups>
                    <telerik:SelectiveScrollingGrid x:Name="grid" Background="Transparent">
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="Auto"/>
                            <ColumnDefinition Width="Auto"/>
                            <ColumnDefinition Width="*"/>
                        </Grid.ColumnDefinitions>
                        <Grid.RowDefinitions>
                            <RowDefinition Height="*"/>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition Height="Auto"/>
                        </Grid.RowDefinitions>
                        <Grid Grid.Column="2" x:Name="PART_SelectiveScrollingElements">
                            <Grid.ColumnDefinitions>
                                <ColumnDefinition Width="Auto"/>
                                <ColumnDefinition Width="*"/>
                            </Grid.ColumnDefinitions>
                            <Border x:Name="SelectionBackground"
                Background="{TemplateBinding Background}"
                Margin="{TemplateBinding Margin}"
                VerticalAlignment="{TemplateBinding VerticalContentAlignment}"
                HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                Padding="{TemplateBinding Padding}"
                Grid.Column="1"/>
                            <Border x:Name="Background_Over"
                Margin="1 1 1 2"
                BorderThickness="1"
                CornerRadius="1"
                BorderBrush="{StaticResource ItemOuterBorder_Over}"
                Visibility="Collapsed"
                Grid.Column="1">
                                <Border x:Name="BackgroundInner_Over" BorderThickness="1" BorderBrush="{StaticResource ItemInnerBorder_Over}" Background="{StaticResource ItemBackground_Over}"/>
                            </Border>
                            <Border x:Name="Background_Selected"
                Margin="1 1 1 2"
                BorderThickness="1"
                CornerRadius="1"
                BorderBrush="{StaticResource ItemOuterBorder_Selected}"
                Visibility="Collapsed"
                Grid.Column="1">
                                <Border BorderThickness="1" BorderBrush="{StaticResource ItemInnerBorder_Selected}" Background="{StaticResource ItemBackground_Selected}"/>
                            </Border>
                            <Border x:Name="Background_Invalid"
                Margin="1 1 1 2"
                BorderThickness="1"
                CornerRadius="1"
                BorderBrush="{StaticResource ItemOuterBorder_Invalid}"
                Visibility="Collapsed"
                Grid.Column="1">
                                <Border BorderThickness="1" BorderBrush="{StaticResource ItemInnerBorder_Invalid}" Background="{StaticResource ItemBackground_Invalid}"/>
                            </Border>
                        </Grid>
                        <telerik:GridViewToggleButton x:Name="PART_ExpandButton"
            HorizontalAlignment="Left"
            HorizontalContentAlignment="Center"
            Width="20"
            Grid.Column="1"
            Grid.ColumnSpan="2"
            IsTabStop="False"
            IsChecked="{Binding IsExpanded, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}">
                            <telerik:GridViewToggleButton.Style>
                                <Style TargetType="telerik:GridViewToggleButton" BasedOn="{StaticResource GridViewToggleButtonStyle}">
                                    <Setter Property="PresentationMode" Value="Arrow"/>
                                </Style>
                            </telerik:GridViewToggleButton.Style>
                        </telerik:GridViewToggleButton>
                        <telerik:DataCellsPresenter Grid.ColumnSpan="2" Grid.Column="1" x:Name="PART_DataCellsPresenter">
                            <telerik:DataCellsPresenter.ItemsPanel>
                                <ItemsPanelTemplate>
                                    <telerik:TreeListCellsPanel/>
                                </ItemsPanelTemplate>
                            </telerik:DataCellsPresenter.ItemsPanel>
                        </telerik:DataCellsPresenter>
                        <Border x:Name="PART_RowBorder"
            BorderBrush="{TemplateBinding HorizontalGridLinesBrush}"
            BorderThickness="{Binding HorizontalGridLinesWidth, RelativeSource={RelativeSource TemplatedParent}, Converter={StaticResource GridLineWidthToThicknessConverter}, ConverterParameter=Bottom}"
            Grid.ColumnSpan="3"
            Grid.Column="1"
            Grid.RowSpan="4"
            VerticalAlignment="Bottom"/>
                        <telerik:DetailsPresenter x:Name="PART_DetailsPresenter" Grid.Column="2" Grid.ColumnSpan="2" Grid.Row="1" Visibility="Collapsed" DetailsProvider="{TemplateBinding DetailsProvider}"/>
                        <Border x:Name="PART_IndicatorPresenter"
            Width="25"
            VerticalAlignment="Stretch"
            Grid.Column="0"
            Visibility="{TemplateBinding RowIndicatorVisibility}"
            telerik:SelectiveScrollingGrid.SelectiveScrollingOrientation="Vertical"
            Grid.RowSpan="3"
            BorderBrush="{StaticResource ControlOuterBorder}"
            BorderThickness="0 0 1 1">
                            <Border x:Name="NavigatorIndicatorBackground"
                Background="{StaticResource GridView_RowIndicatorCellBackground}"
                BorderBrush="{StaticResource ControlInnerBorder}"
                BorderThickness="1">
                                <Grid>
                                    <Grid x:Name="NavigatorIndicator" HorizontalAlignment="Center" VerticalAlignment="Center" Width="11" Height="11" Visibility="Collapsed">
                                        <Path
                            Stretch="Fill"
                            Data="F1 M 32.0234,6.66669L 24.2923,0.0248413L 28.3697,0.0248413L 32,3.14362L 36.1492,6.70819L 32,10.2728L 28.4664,13.3085L 24.2923,13.3085L 32.0234,6.66669 Z"
                            Margin="0"
                            HorizontalAlignment="Center"
                            VerticalAlignment="Center"
                            Width="8"
                            Height="8"
                            Fill="{StaticResource GridView_NavigatorIndicatorBackground}"/>
                                    </Grid>
                                    <Grid x:Name="EditIndicator" HorizontalAlignment="Center" VerticalAlignment="Center" Width="16" Height="10" Visibility="Collapsed">
                                        <Path Fill="{StaticResource GridView_EditIndicatorBackground1}" Stretch="Fill" Data="M14,9 L15,9 15,10 14,10 z M1,9 L2,9 2,10 1,10 z M15,8 L16,8 16,9 15,9 z M0,8 L1,8 1,9 0,9 z M15,1 L16,1 16,2 15,2 z M0,1 L1,1 1,2 0,2 z M14,0 L15,0 15,1 14,1 z M1,0 L2,0 2,1 1,1 z"/>
                                        <Path
                            Fill="{StaticResource GridView_EditIndicatorBackground2}"
                            Stretch="Fill"
                            Margin="1"
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                                        <Path Fill="{StaticResource GridView_EditIndicatorBackground3}" Stretch="Fill" Data="M2,9 L3,9 4,9 5,9 6,9 7,9 8,9 9,9 10,9 11,9 12,9 13,9 14,9 14,10 13,10 12,10 11,10 10,10 9,10 8,10 7,10 6,10 5,10 4,10 3,10 2,10 z M14,8 L15,8 15,9 14,9 z M1,8 L2,8 2,9 1,9 z M15,2 L16,2 16,3 16,4 16,5 16,6 16,7 16,8 15,8 15,7 15,6 15,5 15,4 15,3 z M3,2 L4,2 5,2 6,2 6,3 5,3 5,4 5,5 5,6 5,7 6,7 6,8 5,8 4,8 3,8 3,7 4,7 4,6 4,5 4,4 4,3 3,3 z M0,2 L1,2 1,3 1,4 1,5 1,6 1,7 1,8 0,8 0,7 0,6 0,5 0,4 0,3 z M14,1 L15,1 15,2 14,2 z M1,1 L2,1 2,2 1,2 z M2,0 L3,0 4,0 5,0 6,0 7,0 8,0 9,0 10,0 11,0 12,0 13,0 14,0 14,1 13,1 12,1 11,1 10,1 9,1 8,1 7,1 6,1 5,1 4,1 3,1 2,1 z"/>
                                        <Path
                            Fill="{StaticResource GridView_EditIndicatorBackground4}"
                            Stretch="Fill"
                            Margin="2"
                            Data="M4,0 L5,0 6,0 7,0 8,0 9,0 10,0 11,0 12,0 12,1 12,2 12,3 12,4 12,5.0000001 12,6 11,6 10,6 9,6 8,6 7,6 6,6 5,6 4,6 4,5.0000001 3,5.0000001 3,4 3,3 3,2 3,1 4,1 z M0,0 L1,0 1,1 2,1 2,2 2,3 2,4 2,5.0000001 1,5.0000001 1,6 0,6 0,5.0000001 0,4 0,3 0,2 0,1 z"/>
                                    </Grid>
                                    <Grid x:Name="InvalidEditableIndicator" Visibility="Collapsed" Background="Transparent">
                                        <Grid HorizontalAlignment="Center" VerticalAlignment="Center" Width="16" Height="10">
                                            <Path Fill="{StaticResource GridView_InvalidEditIndicatorBackground1}" Stretch="Fill" Data="M14,9 L15,9 15,10 14,10 z M1,9 L2,9 2,10 1,10 z M15,8 L16,8 16,9 15,9 z M0,8 L1,8 1,9 0,9 z M15,1 L16,1 16,2 15,2 z M0,1 L1,1 1,2 0,2 z M14,0 L15,0 15,1 14,1 z M1,0 L2,0 2,1 1,1 z"/>
                                            <Path
                                Fill="{StaticResource GridView_InvalidEditIndicatorBackground2}"
                                Stretch="Fill"
                                Margin="1"
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                                Fill="{StaticResource GridView_InvalidEditIndicatorBackground4}"
                                Stretch="Fill"
                                Margin="2"
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                                        </Grid>
                                        <ToolTipService.ToolTip>
                                            <ToolTip Placement="Bottom" Content="{TemplateBinding Errors}" Template="{StaticResource TreeListViewRow_ValidationToolTipTemplate}"/>
                                        </ToolTipService.ToolTip>
                                    </Grid>
                                    <Grid x:Name="ErrorIndicator" HorizontalAlignment="Center" VerticalAlignment="Center" Width="16" Height="16" Visibility="Collapsed">
                                        <Path
                            Fill="{StaticResource GridView_ErrorIndicatorBackground1}"
                            Stretch="Fill"
                            Margin="1"
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                            Fill="{StaticResource GridView_ErrorIndicatorBackground2}"
                            Stretch="Fill"
                            Margin="7 3"
                            Data="M1.4901161E-07,8 L1.0000001,8 2.0000002,8 2.0000002,9 2.0000002,10 1.0000003,10 1.0000003,9 1.0000001,10 1.4901161E-07,10 1.4901161E-07,9 z M1.4901161E-07,0 L1.0000001,0 2.0000002,0 2.0000002,1 2.0000002,2 2.0000002,3 2.0000002,4.0000001 2.0000002,5 2.0000002,5.9999999 2.0000002,7 1.0000001,7 1.4901161E-07,7 1.4901161E-07,5.9999999 1.4901161E-07,5 1.4901161E-07,4.0000001 1.4901161E-07,3 1.4901161E-07,2 0,1 z"/>
                                        <Path Fill="{StaticResource GridView_ErrorIndicatorBackground3}" Stretch="Fill" Data="M4,15 L5,15 6,15 7,15 8,15 9,15 10,15 11,15 12,15 12,16 11,16 10,16 9,16 8,16 7,16 6,16 5,16 4,16 z M12,14 L13,14 13,15 12,15 z M3,14 L4,14 4,15 3,15 z M13,13 L14,13 14,14 13,14 z M2,13 L3,13 3,14 2,14 z M14,12 L15,12 15,13 14,13 z M1,12 L2,12 2,13 1,13 z M7,11 L7,12 7,13 8,13 9,13 9,12 9,11 8,11 z M15,4 L16,4 16,5 16,6 16,7 16,8 16,9 16,10 16,11 16,12 15,12 15,11 15,10 15,9 15,8 15,7 15,6 15,5 z M0,4 L1,4 1,5 1,6 1,7 1,8 1,9 1,10 1,11 1,12 0,12 0,11 0,10 0,9 0,8 0,7 0,6 0,5 z M14,3 L15,3 15,4 14,4 z M7,3 L7,4 7,5 7,6 7,7 7,8 7,9 7,10 8,10 9,10 9,9 9,8 9,7 9,6 9,5 9,4 9,3 8,3 z M1,3 L2,3 2,4 1,4 z M13,2 L14,2 14,3 13,3 z M4,2 L5,2 6,2 7,2 8,2 9,2 10,2 11,2 12,2 12,3 13,3 13,4 14,4 14,5 14,6 14,7 14,8 14,9 14,10 14,11 14,12 13,12 13,13 12,13 12,14 11,14 10,14 9,14 8,14 7,14 6,14 5,14 4,14 4,13 3,13 3,12 2,12 2,11 2,10 2,9 2,8 2,7 2,6 2,5 2,4 3,4 3,3 4,3 z M2,2 L3,2 3,3 2,3 z M12,1 L13,1 13,2 12,2 z M3,1 L4,1 4,2 3,2 z M4,0 L5,0 6,0 7,0 8,0 9,0 10,0 11,0 12,0 12,1 11,1 10,1 9,1 8,1 7,1 6,1 5,1 4,1 z"/>
                                        <ToolTipService.ToolTip>
                                            <ToolTip x:Name="validationTooltip" Placement="Bottom" Content="{TemplateBinding Errors}" Template="{StaticResource TreeListViewRow_ValidationToolTipTemplate}"/>
                                        </ToolTipService.ToolTip>
                                    </Grid>
                                    <Border x:Name="PART_RowResizer" Background="Transparent" Height="2" VerticalAlignment="Bottom" Cursor="SizeNS"/>
                                </Grid>
                            </Border>
                        </Border>
                    </telerik:SelectiveScrollingGrid>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

For your convenience, I'm also attaching a sample project with the implementation. Bear in mind that if you're using a different theme, you should modify it accordingly.

Do let me know if you manage to achieve the desired result.

Regards,
Dilyan Traykov
Telerik by Progress

[Dean]

Thanks Dilyan, applying the custom TreeListViewRow style based on TreeListViewRowStyle and setting the Background property value to Transparent worked for me with or without the included control template.

Regards,

Dean