Formatted code.
<UserControl><UserControl.Resources><DataTemplatex:Key="AdvancedVariableTemplate"> <RadioButtonChecked="itemContainerRadio_Checked"Content="{Binding CustomName}"ToolTip="{Binding TooltipString}"/> </DataTemplate> <HierarchicalDataTemplatex:Key="AdvancedGroupSeriesRadioTemplate"ItemsSource="{Binding LstAppDataSeries}"> <TextBlockText="{Binding CustomName}"FontWeight="Bold"/> </HierarchicalDataTemplate> <HierarchicalDataTemplatex:Key="AdvancedGroupSideTemplate"ItemsSource="{Binding LstAppDataSeriesSides}"> <TextBlockText="{Binding CustomName}"FontWeight="Bold"/> </HierarchicalDataTemplate> <VariablesGroup:VariablesHierarchicalTemplatex:Key="AdvancedVariableItemTemplate" VariablesGroupsTemplate="{StaticResource AdvancedGroupSideTemplate}" VariableSideTemplate="{StaticResource AdvancedGroupSeriesRadioTemplate}" VariableTemplate="{StaticResource AdvancedVariableTemplate}"/> <VariablesGroup:AdvVariableContainerStyleSelectorx:Key="AdvancedVariableStyleSelector" DarkThemeStyle="{StaticResource AdvancedVariableItemContainerStyle}" LightThemeStyle="{StaticResource AdvancedVariableItemContainerStyle}"/> </UserControl.Resources><Grid><telerik:RadTreeViewx:Name="lstVariablesAdvanced"SelectedItem="{DynamicResource AdvancedVariableItemContainerStyle}"VerticalAlignment="Stretch"Grid.Row="1"Grid.ColumnSpan="2"BorderThickness="0,0,0,0"ScrollViewer.CanContentScroll="False"IsEditable="True"SelectionMode="Extended"ItemsSource="{Binding LstAppDataSeriesGrouping}"IsDropPreviewLineEnabled="False"IsDragPreviewEnabled="True"IsDragTooltipEnabled="False"MouseDown="lstVariablesAdvanced_MouseDown"IsSingleExpandPath="True"IsExpandOnSingleClickEnabled="False" IsDragDropEnabled="False"PreviewKeyDown="lstVariables_PreviewKeyDown"IsLineEnabled="True"ItemTemplateSelector="{StaticResource AdvancedVariableItemTemplate}"ItemContainerStyleSelector="{StaticResource AdvancedVariableStyleSelector}" Margin="10,0,6,0"></telerik:RadTreeView></Grid></UserControl><ResourceDictionary> <!-- ItemContainerStyleSelector --><Stylex:Key="AdvancedVariableItemContainerStyle"TargetType="telerik:RadTreeViewItem"BasedOn="{StaticResource RadTreeViewItemStyle}"> <SetterProperty="Background"Value="Red"/> <SetterProperty="Foreground"Value="Green"/></Style></ResourceDictionary>classAdvVariableContainerStyleSelector : StyleSelector { privateStyle darkThemeStyle; privateStyle lightThemeStyle; publicoverrideStyle SelectStyle(objectitem, DependencyObject container) { Configuration config = UserConfigurations.getConfig(); if(config.AppSettings.Settings["CurrentTheme"] != null) { switch(config.AppSettings.Settings["CurrentTheme"].Value.ToString().ToUpper()) { case"LIGHT": returnlightThemeStyle; case"STANDARD": returnlightThemeStyle; case"DARK": returndarkThemeStyle; default: returnnull; } } else returnnull; } publicStyle DarkThemeStyle { get { returnthis.darkThemeStyle; } set { this.darkThemeStyle = value; } } publicStyle LightThemeStyle { get { returnthis.lightThemeStyle; } set { this.lightThemeStyle = value; } } }