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I can't click combobox and change item.in wpf

I was trying to make a transparent combo box.
I found this article and followed.
WPF combobox transparent background not working with Windows 10
It was successful to make this combo box transparent. Like below.
But after that, I can't control the combo box. I can't click and change
items.
This is my style for combo box.
<Style x:Key="ComboBoxStyle_transparent" TargetType="{x:Type ComboBox}">
<Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}"/>
<Setter Property="Background" Value="{StaticResource ComboBox.Static.Background}"/>
<Setter Property="BorderBrush" Value="{StaticResource ComboBox.Static.Border}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
<Setter Property="BorderThickness" Value="0"/>
<Setter Property="VerticalAlignment" Value="Center" />
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<Setter Property="Padding" Value="6,3,5,3"/>
<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
<Setter Property="ScrollViewer.PanningMode" Value="Both"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template" Value="{StaticResource ComboBoxTemplate}"/>
<Style.Triggers>
<Trigger Property="IsEditable" Value="true">
<Setter Property="IsTabStop" Value="false"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="Template" Value="{StaticResource ComboBoxEditableTemplate}"/>
</Trigger>
</Style.Triggers>
</Style>
And this is setting I did to make background clear.
<SolidColorBrush x:Key="ComboBox.Static.Background" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Static.Border" Color="Transparent"/>
And this is Xaml code.
<ComboBox Name="ReferenceCombobox"
Grid.Column="1" Grid.ColumnSpan="3"
Grid.Row="1"
Height="30" MinWidth="120"
VerticalAlignment="Top"
HorizontalAlignment="Left"
ItemsSource ="{Binding Path=ReferenceNameList, Mode=TwoWay}"
SelectedItem="{Binding Path=SelectedReference, Mode=TwoWay}"
Text="Choose item to use." Style="{DynamicResource ComboBoxStyle_transparent}"
IsEditable="True"
IsEnabled="True"
SelectedIndex="0"
>
</ComboBox>
I have tried to change & add the properties I found. but it doesn't work at all.
Is there anything I missed?
Thanks for the help. here is ComboBoxEditableTemplate xaml code.
<ControlTemplate x:Key="ComboBoxEditableTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="shadow" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
<Border x:Name="dropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid" RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas" HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="opaqueRect" Fill="{Binding Background, ElementName=dropDownBorder}" Height="{Binding ActualHeight, ElementName=dropDownBorder}" Width="{Binding ActualWidth, ElementName=dropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxToggleButton}"/>
<Border x:Name="border" Background="{StaticResource TextBox.Static.Background}" Margin="{TemplateBinding BorderThickness}">
<TextBox x:Name="PART_EditableTextBox" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" IsReadOnly="{Binding IsReadOnly, RelativeSource={RelativeSource TemplatedParent}}" Margin="{TemplateBinding Padding}" Style="{StaticResource ComboBoxEditableTextBox}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Opacity" TargetName="border" Value="0.56"/>
</Trigger>
<Trigger Property="IsKeyboardFocusWithin" Value="true">
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="shadow" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="shadow" Value="#71000000"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="dropDownBorder" Value="95"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="opaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="opaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
And this is ComboBoxTemplate code.
<ControlTemplate x:Key="ComboBoxTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Margin="1" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="shadow" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
<Border x:Name="dropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid" RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas" HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="opaqueRect" Fill="{Binding Background, ElementName=dropDownBorder}" Height="{Binding ActualHeight, ElementName=dropDownBorder}" Width="{Binding ActualWidth, ElementName=dropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxToggleButton}"/>
<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}" ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" Content="{TemplateBinding SelectionBoxItem}" ContentStringFormat="{TemplateBinding SelectionBoxItemStringFormat}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" IsHitTestVisible="false" Margin="{TemplateBinding Padding}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="shadow" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="shadow" Value="#71000000"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="dropDownBorder" Value="95"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="opaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="opaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>

WPF combobox prevent selection update

I want to be able to select a value in a ComboBox but avoid the selected value updating.
In other words, for the picture above, I want the empty selection to remain empty when one of the items is selected.
I've tried a ton of different solutions - various bindings on SelectedIndex, SelectedValue, SelectionChanged, playing with IsEditable, IsReadonly, IsHitTestVisible, Text, etc, etc, etc.
How can I prevent the combobox from automatically updating the text on selection, but still have it able to select a choice?
Sample code:
<ComboBox
IsReadOnly="True"
IsEditable="False"
Text="..."
>
<ComboBoxItem>
<TextBlock>Close</TextBlock>
</ComboBoxItem>
<ComboBoxItem>
<TextBlock>Delete</TextBlock>
</ComboBoxItem>
</ComboBox>

As an experienced WPF developer, I'll put some light on this problem.
Basically, you have tried a ton of different solutions using the wrong instruments.
In WPF each control has a default style, which fully describes what you'll see on the screen (nothing hidden here). What is not that obvious, however, is how to take a look at the default style of a control.
(I work with VS 2013, but the steps described below should work in later versions as well)
Create a new project in 'Blend for Visual Studio 2013"
In the "Assets" tab search box type "ComboBox" and double click on it
Right click on the ComboBox you've just added in the "Objects and timeline" panel and select "Edit template -> Edit a copy..."
Switch to code view (the button is on the top right side)
Yeah, the default styles are quite lengthy!
Now, what we are interested in is the ControlTemplate. There must be some control in this tempplate responsible for displaying the selected item. If you are in a hurry, just find it and delete the appropriate binding.
Below is an example solution, which I would call "Couple hours before deadline solution". Read the comments in the XAML for the proper approach.
<Window x:Class="ComboBoxAdventures.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero2"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<Style x:Key="FocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle Margin="2" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<LinearGradientBrush x:Key="ComboBox.Static.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFF0F0F0" Offset="0.0"/>
<GradientStop Color="#FFE5E5E5" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.Static.Border" Color="#FFACACAC"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Border" Color="#FFABADB3"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Background" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Border" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.MouseOver.Glyph" Color="#FF000000"/>
<LinearGradientBrush x:Key="ComboBox.MouseOver.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFECF4FC" Offset="0.0"/>
<GradientStop Color="#FFDCECFC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.MouseOver.Border" Color="#FF7EB4EA"/>
<SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Border" Color="#FF7EB4EA"/>
<LinearGradientBrush x:Key="ComboBox.MouseOver.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFEBF4FC" Offset="0.0"/>
<GradientStop Color="#FFDCECFC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Button.Border" Color="#FF7EB4EA"/>
<SolidColorBrush x:Key="ComboBox.Pressed.Glyph" Color="#FF000000"/>
<LinearGradientBrush x:Key="ComboBox.Pressed.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFDAECFC" Offset="0.0"/>
<GradientStop Color="#FFC4E0FC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.Pressed.Border" Color="#FF569DE5"/>
<SolidColorBrush x:Key="ComboBox.Pressed.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.Pressed.Editable.Border" Color="#FF569DE5"/>
<LinearGradientBrush x:Key="ComboBox.Pressed.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFDAEBFC" Offset="0.0"/>
<GradientStop Color="#FFC4E0FC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.Pressed.Editable.Button.Border" Color="#FF569DE5"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Glyph" Color="#FFBFBFBF"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Background" Color="#FFF0F0F0"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Border" Color="#FFD9D9D9"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Border" Color="#FFBFBFBF"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Background" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Border" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Static.Glyph" Color="#FF606060"/>
<Style x:Key="ComboBoxToggleButton" TargetType="{x:Type ToggleButton}">
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="IsTabStop" Value="false"/>
<Setter Property="Focusable" Value="false"/>
<Setter Property="ClickMode" Value="Press"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border x:Name="templateRoot" BorderBrush="{StaticResource ComboBox.Static.Border}" BorderThickness="{TemplateBinding BorderThickness}" Background="{StaticResource ComboBox.Static.Background}" SnapsToDevicePixels="true">
<Border x:Name="splitBorder" BorderBrush="Transparent" BorderThickness="1" HorizontalAlignment="Right" Margin="0" SnapsToDevicePixels="true" Width="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}">
<Path x:Name="arrow" Data="F1 M 0,0 L 2.667,2.66665 L 5.3334,0 L 5.3334,-1.78168 L 2.6667,0.88501 L0,-1.78168 L0,0 Z" Fill="{StaticResource ComboBox.Static.Glyph}" HorizontalAlignment="Center" Margin="0" VerticalAlignment="Center"/>
</Border>
</Border>
<ControlTemplate.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
<Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsPressed, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsEnabled, RelativeSource={RelativeSource Self}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Static.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Static.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.Static.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.Static.Editable.Button.Border}"/>
</MultiDataTrigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Fill" TargetName="arrow" Value="{StaticResource ComboBox.MouseOver.Glyph}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Border}"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.MouseOver.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.MouseOver.Editable.Button.Border}"/>
</MultiDataTrigger>
<Trigger Property="IsPressed" Value="true">
<Setter Property="Fill" TargetName="arrow" Value="{StaticResource ComboBox.Pressed.Glyph}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsPressed, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Border}"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsPressed, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.Pressed.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.Pressed.Editable.Button.Border}"/>
</MultiDataTrigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Fill" TargetName="arrow" Value="{StaticResource ComboBox.Disabled.Glyph}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsEnabled, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Border}"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsEnabled, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.Disabled.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.Disabled.Editable.Button.Border}"/>
</MultiDataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<ControlTemplate x:Key="ComboBoxTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Margin="1" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="shadow" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
<Border x:Name="dropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid" RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas" HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="opaqueRect" Fill="{Binding Background, ElementName=dropDownBorder}" Height="{Binding ActualHeight, ElementName=dropDownBorder}" Width="{Binding ActualWidth, ElementName=dropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxToggleButton}"/>
<!-- This content presenter displays the selected item.
The easiest way is just to remove the Content binding as shown below.
The proper way to do those kind of things, however, is to inherit from ComboBox,
define a dependency property ShowSelectedItem and then add a trigger for the ContentPreseneter below,
which changes the Content based on the value of the ShowSelectedItem.
You'll also need a custom IValueConverter for mapping bool to Hidden/Visible and some
googling about Generic.xaml and how to overwrite the DefaultStyle dependency property in the static constructor.
You may also wonder why I didn't just comment out the whole ContentPresenter.
Well, lets say it just keeps the 'backbone' of the control :)
-->
<ContentPresenter x:Name="contentPresenter" Tag="I have removed only this part: Content='{TemplateBinding SelectionBoxItem}'"
ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}"
Content="" ContentStringFormat="{TemplateBinding SelectionBoxItemStringFormat}"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
IsHitTestVisible="false" Margin="{TemplateBinding Padding}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}">
</ContentPresenter>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="shadow" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="shadow" Value="#71000000"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="dropDownBorder" Value="95"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="opaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="opaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
<SolidColorBrush x:Key="TextBox.Static.Background" Color="#FFFFFFFF"/>
<Style x:Key="ComboBoxEditableTextBox" TargetType="{x:Type TextBox}">
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="AllowDrop" Value="true"/>
<Setter Property="MinWidth" Value="0"/>
<Setter Property="MinHeight" Value="0"/>
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer x:Name="PART_ContentHost" Background="Transparent" Focusable="false" HorizontalScrollBarVisibility="Hidden" VerticalScrollBarVisibility="Hidden"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<ControlTemplate x:Key="ComboBoxEditableTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="shadow" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
<Border x:Name="dropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid" RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas" HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="opaqueRect" Fill="{Binding Background, ElementName=dropDownBorder}" Height="{Binding ActualHeight, ElementName=dropDownBorder}" Width="{Binding ActualWidth, ElementName=dropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxToggleButton}"/>
<Border x:Name="border" Background="{StaticResource TextBox.Static.Background}" Margin="{TemplateBinding BorderThickness}">
<TextBox x:Name="PART_EditableTextBox" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" IsReadOnly="{Binding IsReadOnly, RelativeSource={RelativeSource TemplatedParent}}" Margin="{TemplateBinding Padding}" Style="{StaticResource ComboBoxEditableTextBox}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Opacity" TargetName="border" Value="0.56"/>
</Trigger>
<Trigger Property="IsKeyboardFocusWithin" Value="true">
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="shadow" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="shadow" Value="#71000000"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="dropDownBorder" Value="95"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="opaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="opaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
<Style x:Key="Style.ComboBox.Ghost" TargetType="{x:Type ComboBox}">
<Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}"/>
<Setter Property="Background" Value="{StaticResource ComboBox.Static.Background}"/>
<Setter Property="BorderBrush" Value="{StaticResource ComboBox.Static.Border}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<Setter Property="Padding" Value="6,3,5,3"/>
<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
<Setter Property="ScrollViewer.PanningMode" Value="Both"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template" Value="{StaticResource ComboBoxTemplate}"/>
<Style.Triggers>
<Trigger Property="IsEditable" Value="true">
<Setter Property="IsTabStop" Value="false"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="Template" Value="{StaticResource ComboBoxEditableTemplate}"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<StackPanel>
<ComboBox Style="{StaticResource Style.ComboBox.Ghost}" ItemsSource="{Binding SelectedDummyModel}" SelectedItem="{Binding DummyModels}"/>
</StackPanel>
</Window>

Here's something I came up with based on adding buttons to the combobox.
This is just two buttons added to the combobox.
<ComboBox x:Name="cboBox" HorizontalAlignment="Left" VerticalAlignment="Top" Width="151" Margin="182,132,0,0" SelectionChanged="cboBox_SelectionChanged" Grid.Column="1" Height="22">
<Button Content="Close" Width="141" Click="Button_Close" Height="51"/>
<Button Content="Delete" Width="141" Click="Button_Delete" Height="51"/>
</ComboBox>
I then went into the code behind and added code to handle the click event for each button.
As you will see we aren't even dealing with the combobox other than using it to show the buttons and then closing the dropdown upon clicking one of the buttons.
private void Button_Close(object sender, RoutedEventArgs e)
{
lbl1.Content = "Close Clicked";
cboBox.IsDropDownOpen = false;
}
private void Button_Delete(object sender, RoutedEventArgs e)
{
lbl1.Content = "Delete Clicked";
cboBox.IsDropDownOpen = false;
}
I really need to get better versed with WPF. I actually enjoyed messing with this.

How to change the color of a selected item of a ComboboxItem which includes a TextBlock?

I have the following XAML of a Combobox:
<ComboBox>
<ComboBoxItem>
<TextBlock FontWeight="Bold" Background="PaleGreen">1</TextBlock>
</ComboBoxItem>
<ComboBoxItem>
<TextBlock FontWeight="Bold" Background="Salmon">2</TextBlock>
</ComboBoxItem>
<ComboBoxItem>
<TextBlock FontWeight="Bold" Background="PaleTurquoise">3</TextBlock>
</ComboBoxItem>
<ComboBoxItem>
<TextBlock FontWeight="Bold" Background="Gold">4</TextBlock>
</ComboBoxItem>
<ComboBoxItem>
<TextBlock FontWeight="Bold" Background="Black" Foreground="White">5</TextBlock>
</ComboBoxItem>
<ComboBoxItem>
<TextBlock FontWeight="Bold" Background="Gray">6</TextBlock>
</ComboBoxItem>
</ComboBox>
The following pictures shows my problem:
Combobox open
Combobox closed
So you can see in the picture "Combobox closed" that the number "4" has no color, but I want that the text "4" is yellow. Can you help me?

#janonimus: When I add a template as you said it has following code:
<Window.Resources>
<ControlTemplate x:Key="ComboBoxControlTemplate1" TargetType="{x:Type ComboBox}">
<Grid x:Name="Placement" SnapsToDevicePixels="True">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="True" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="Shdw" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=Placement}">
<Border x:Name="DropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid RenderOptions.ClearTypeHint="Enabled">
<Canvas HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="OpaqueRect" Fill="{Binding Background, ElementName=DropDownBorder}" Height="{Binding ActualHeight, ElementName=DropDownBorder}" Width="{Binding ActualWidth, ElementName=DropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<Themes:ListBoxChrome x:Name="Border" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" RenderMouseOver="{TemplateBinding IsMouseOver}" RenderFocused="{TemplateBinding IsKeyboardFocusWithin}"/>
<TextBox x:Name="PART_EditableTextBox" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" IsReadOnly="{Binding IsReadOnly, RelativeSource={RelativeSource TemplatedParent}}" Margin="{TemplateBinding Padding}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}">
<TextBox.Style>
<Style TargetType="{x:Type TextBox}">
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="AllowDrop" Value="True"/>
<Setter Property="MinWidth" Value="0"/>
<Setter Property="MinHeight" Value="0"/>
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer x:Name="PART_ContentHost" Background="Transparent" Focusable="False" HorizontalScrollBarVisibility="Hidden" VerticalScrollBarVisibility="Hidden"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</TextBox.Style>
</TextBox>
<ToggleButton Grid.Column="1" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}">
<ToggleButton.Style>
<Style TargetType="{x:Type ToggleButton}">
<Setter Property="OverridesDefaultStyle" Value="True"/>
<Setter Property="IsTabStop" Value="False"/>
<Setter Property="Focusable" Value="False"/>
<Setter Property="ClickMode" Value="Press"/>
<Setter Property="Background" Value="Transparent"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Themes:ButtonChrome x:Name="Chrome" BorderBrush="{TemplateBinding BorderBrush}" Background="{TemplateBinding Background}" RenderMouseOver="{TemplateBinding IsMouseOver}" RenderPressed="{TemplateBinding IsPressed}" RoundCorners="False" SnapsToDevicePixels="True" Width="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}">
<Path x:Name="Arrow" Data="M0,0L3.5,4 7,0z" Fill="Black" HorizontalAlignment="Center" Margin="0,1,0,0" VerticalAlignment="Center"/>
</Themes:ButtonChrome>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="RenderPressed" TargetName="Chrome" Value="True"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Fill" TargetName="Arrow" Value="#FFAFAFAF"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ToggleButton.Style>
</ToggleButton>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsKeyboardFocusWithin" Value="True">
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="IsDropDownOpen" Value="True">
<Setter Property="RenderFocused" TargetName="Border" Value="True"/>
</Trigger>
<Trigger Property="HasItems" Value="False">
<Setter Property="Height" TargetName="DropDownBorder" Value="95"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
<Setter Property="Background" Value="#FFF4F4F4"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="True"/>
<Condition>
<Condition.Value>
<System:Boolean>False</System:Boolean>
</Condition.Value>
</Condition>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="False"/>
</MultiTrigger>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="True">
<Setter Property="Margin" TargetName="Shdw" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="Shdw" Value="#71000000"/>
</Trigger>
<Trigger Property="CanContentScroll" SourceName="DropDownScrollViewer" Value="False">
<Setter Property="Canvas.Top" TargetName="OpaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="OpaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Window.Resources>
In addition, an error is thrown as soon as I have inserted the template:
InvalidOperationException: Nicht-NULL-Wert für "Property" erforderlich.
EDIT:
I have the solution. It was quite easy :D I don't need a template. I just added triggers:
<Style TargetType="ComboBox">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="FontSize" Value="10"/>
<Setter Property="HorizontalAlignment" Value="Center"/>
<Setter Property="VerticalAlignment" Value="Center"/>
<Setter Property="Width" Value="115"/>
<Setter Property="Foreground" Value="Black"/>
<Setter Property="BorderBrush" Value="White"/>
<Setter Property="SelectedIndex" Value="0"/>
<Setter Property="HorizontalContentAlignment" Value="Center"/>
<Setter Property="IsEditable" Value="True"/>
<EventSetter Event="SelectionChanged" Handler="SelectionChanged"/>
<Style.Triggers>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Opacity" Value="0.4"/>
</Trigger>
<Trigger Property="SelectedIndex" Value="0">
<Setter Property="Background" Value="PaleGreen"/>
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="SelectedIndex" Value="1">
<Setter Property="Background" Value="Salmon"/>
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="SelectedIndex" Value="2">
<Setter Property="Background" Value="PaleTurquoise"/>
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="SelectedIndex" Value="3">
<Setter Property="Background" Value="Gold"/>
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="SelectedIndex" Value="4">
<Setter Property="Background" Value="Black"/>
<Setter Property="Foreground" Value="White"/>
</Trigger>
<Trigger Property="SelectedIndex" Value="5">
<Setter Property="Background" Value="Gray"/>
<Setter Property="Foreground" Value="Black"/>
</Trigger>
</Style.Triggers>
</Style>

You need to edit the template of the ComboBox.
Go to [Document Outline], right-click the ComboBox, Edit Template->Edit a Copy.
Then find the "ComboBoxEditableTemplate" and edit the Border the contains the "PART_EditableTextBox". Here's the specific part of the generated code::
...
<ControlTemplate x:Key="ComboBoxEditableTemplate"
TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot"
SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="0"
MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" />
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup"
Grid.ColumnSpan="2"
AllowsTransparency="true"
IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}"
Placement="Bottom"
PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}">
<Themes:SystemDropShadowChrome x:Name="shadow"
MinWidth="{Binding ActualWidth, ElementName=templateRoot}"
MaxHeight="{TemplateBinding MaxDropDownHeight}"
Color="Transparent">
<Border x:Name="dropDownBorder"
Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"
BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}"
BorderThickness="1">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid"
RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas"
Width="0"
Height="0"
HorizontalAlignment="Left"
VerticalAlignment="Top">
<Rectangle x:Name="opaqueRect"
Width="{Binding ActualWidth, ElementName=dropDownBorder}"
Height="{Binding ActualHeight, ElementName=dropDownBorder}"
Fill="{Binding Background, ElementName=dropDownBorder}" />
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter"
KeyboardNavigation.DirectionalNavigation="Contained"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" />
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton"
Grid.ColumnSpan="2"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
Style="{StaticResource ComboBoxToggleButton}" />
<!-- EDIT THIS PART LIKE SO -->
<Border x:Name="border"
Margin="{TemplateBinding BorderThickness}"
Background="{Binding SelectedItem.Background, RelativeSource={RelativeSource FindAncestor, AncestorType={x:Type ComboBox}}, FallbackValue=Transparent}">
<!-- Background="{StaticResource TextBox.Static.Background}"> -->
<!-- //////////////////////// -->
<TextBox x:Name="PART_EditableTextBox"
Margin="{TemplateBinding Padding}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
IsReadOnly="{Binding IsReadOnly, RelativeSource={RelativeSource TemplatedParent}}"
Style="{StaticResource ComboBoxEditableTextBox}" />
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter TargetName="border" Property="Opacity" Value="0.56" />
</Trigger>
<Trigger Property="IsKeyboardFocusWithin" Value="true">
<Setter Property="Foreground" Value="Black" />
</Trigger>
<Trigger SourceName="PART_Popup" Property="HasDropShadow" Value="true">
<Setter TargetName="shadow" Property="Margin" Value="0,0,5,5" />
<Setter TargetName="shadow" Property="Color" Value="#71000000" />
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter TargetName="dropDownBorder" Property="Height" Value="95" />
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true" />
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false" />
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false" />
</MultiTrigger>
<Trigger SourceName="DropDownScrollViewer" Property="ScrollViewer.CanContentScroll" Value="false">
<Setter TargetName="opaqueRect" Property="Canvas.Top" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}" />
<Setter TargetName="opaqueRect" Property="Canvas.Left" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
...
After that, you can use it like the following, without using TextBlocks:
<ComboBox IsEditable="True"
Style="{DynamicResource YourComboBoxStyleName}">
<ComboBoxItem Background="PaleGreen"
Content="1"
FontWeight="Bold" />
<ComboBoxItem Background="Salmon"
Content="2"
FontWeight="Bold" />
<ComboBoxItem Background="PaleTurquoise"
Content="3"
FontWeight="Bold" />
<ComboBoxItem Background="Gold"
Content="4"
FontWeight="Bold" />
<ComboBoxItem Background="Black"
Content="5"
FontWeight="Bold"
Foreground="White" />
<ComboBoxItem Background="Gray"
Content="6"
FontWeight="Bold" />
</ComboBox>

changing border of combo box in wpf c#

I want to change combo box border color if it is empty.
I tried with following code, which does not work. For text box, it was working fine.
in xaml
<ComboBox HorizontalAlignment="Left" Height="23" Margin="125,14,0,0" VerticalAlignment="Top" Width="151" Name="CountryName" ItemsSource="{Binding DpData}" DisplayMemberPath="CountryName" SelectedValuePath="CountryID" Grid.Column="1" Grid.ColumnSpan="2" BorderThickness="3" BorderBrush="{x:Null}" />
in C#
if (CountryName.Text == "")
{
CountryName.BorderBrush = Brushes.Red;
}

While Snooping i have found that, BorderBrush property not being set to InnerProperty. Here i've included VisualStudio generated ComboBox template with Modified codes.
<Window.Resources>
<Style x:Key="FocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle Margin="2" SnapsToDevicePixels="true" Stroke="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" StrokeThickness="1" StrokeDashArray="1 2"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<LinearGradientBrush x:Key="ComboBox.Static.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFF0F0F0" Offset="0.0"/>
<GradientStop Color="#FFE5E5E5" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.Static.Border" Color="#FFACACAC"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Border" Color="#FFABADB3"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Background" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Static.Editable.Button.Border" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.MouseOver.Glyph" Color="#FF000000"/>
<LinearGradientBrush x:Key="ComboBox.MouseOver.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFECF4FC" Offset="0.0"/>
<GradientStop Color="#FFDCECFC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.MouseOver.Border" Color="#FF7EB4EA"/>
<SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Border" Color="#FF7EB4EA"/>
<LinearGradientBrush x:Key="ComboBox.MouseOver.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFEBF4FC" Offset="0.0"/>
<GradientStop Color="#FFDCECFC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.MouseOver.Editable.Button.Border" Color="#FF7EB4EA"/>
<SolidColorBrush x:Key="ComboBox.Pressed.Glyph" Color="#FF000000"/>
<LinearGradientBrush x:Key="ComboBox.Pressed.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFDAECFC" Offset="0.0"/>
<GradientStop Color="#FFC4E0FC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.Pressed.Border" Color="#FF569DE5"/>
<SolidColorBrush x:Key="ComboBox.Pressed.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.Pressed.Editable.Border" Color="#FF569DE5"/>
<LinearGradientBrush x:Key="ComboBox.Pressed.Editable.Button.Background" EndPoint="0,1" StartPoint="0,0">
<GradientStop Color="#FFDAEBFC" Offset="0.0"/>
<GradientStop Color="#FFC4E0FC" Offset="1.0"/>
</LinearGradientBrush>
<SolidColorBrush x:Key="ComboBox.Pressed.Editable.Button.Border" Color="#FF569DE5"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Glyph" Color="#FFBFBFBF"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Background" Color="#FFF0F0F0"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Border" Color="#FFD9D9D9"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Border" Color="#FFBFBFBF"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Background" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Disabled.Editable.Button.Border" Color="Transparent"/>
<SolidColorBrush x:Key="ComboBox.Static.Glyph" Color="#FF606060"/>
<Style x:Key="ComboBoxToggleButton" TargetType="{x:Type ToggleButton}">
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="IsTabStop" Value="false"/>
<Setter Property="Focusable" Value="false"/>
<Setter Property="ClickMode" Value="Press"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border x:Name="templateRoot" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{StaticResource ComboBox.Static.Background}" SnapsToDevicePixels="true">
<Border x:Name="splitBorder" BorderBrush="Transparent" BorderThickness="1" HorizontalAlignment="Right" Margin="0" SnapsToDevicePixels="true" Width="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}">
<Path x:Name="arrow" Data="F1 M 0,0 L 2.667,2.66665 L 5.3334,0 L 5.3334,-1.78168 L 2.6667,0.88501 L0,-1.78168 L0,0 Z" Fill="{StaticResource ComboBox.Static.Glyph}" HorizontalAlignment="Center" Margin="0" VerticalAlignment="Center"/>
</Border>
</Border>
<ControlTemplate.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
<Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsPressed, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsEnabled, RelativeSource={RelativeSource Self}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Static.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Static.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.Static.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.Static.Editable.Button.Border}"/>
</MultiDataTrigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Fill" TargetName="arrow" Value="{StaticResource ComboBox.MouseOver.Glyph}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Border}"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.MouseOver.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.MouseOver.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.MouseOver.Editable.Button.Border}"/>
</MultiDataTrigger>
<Trigger Property="IsPressed" Value="true">
<Setter Property="Fill" TargetName="arrow" Value="{StaticResource ComboBox.Pressed.Glyph}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsPressed, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Border}"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsPressed, RelativeSource={RelativeSource Self}}" Value="true"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Pressed.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.Pressed.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.Pressed.Editable.Button.Border}"/>
</MultiDataTrigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Fill" TargetName="arrow" Value="{StaticResource ComboBox.Disabled.Glyph}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsEnabled, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="false"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Border}"/>
</MultiDataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsEnabled, RelativeSource={RelativeSource Self}}" Value="false"/>
<Condition Binding="{Binding IsEditable, RelativeSource={RelativeSource AncestorType={x:Type ComboBox}}}" Value="true"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Editable.Background}"/>
<Setter Property="BorderBrush" TargetName="templateRoot" Value="{StaticResource ComboBox.Disabled.Editable.Border}"/>
<Setter Property="Background" TargetName="splitBorder" Value="{StaticResource ComboBox.Disabled.Editable.Button.Background}"/>
<Setter Property="BorderBrush" TargetName="splitBorder" Value="{StaticResource ComboBox.Disabled.Editable.Button.Border}"/>
</MultiDataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<ControlTemplate x:Key="ComboBoxTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Margin="1" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="shadow" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
<Border x:Name="dropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid" RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas" HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="opaqueRect" Fill="{Binding Background, ElementName=dropDownBorder}" Height="{Binding ActualHeight, ElementName=dropDownBorder}" Width="{Binding ActualWidth, ElementName=dropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxToggleButton}"/>
<ContentPresenter x:Name="contentPresenter" ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}" ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" Content="{TemplateBinding SelectionBoxItem}" ContentStringFormat="{TemplateBinding SelectionBoxItemStringFormat}" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" IsHitTestVisible="false" Margin="{TemplateBinding Padding}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="shadow" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="shadow" Value="#71000000"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="dropDownBorder" Value="95"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="opaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="opaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
<SolidColorBrush x:Key="TextBox.Static.Background" Color="#FFFFFFFF"/>
<Style x:Key="ComboBoxEditableTextBox" TargetType="{x:Type TextBox}">
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="AllowDrop" Value="true"/>
<Setter Property="MinWidth" Value="0"/>
<Setter Property="MinHeight" Value="0"/>
<Setter Property="FocusVisualStyle" Value="{x:Null}"/>
<Setter Property="ScrollViewer.PanningMode" Value="VerticalFirst"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TextBox}">
<ScrollViewer x:Name="PART_ContentHost" Background="Transparent" Focusable="false" HorizontalScrollBarVisibility="Hidden" VerticalScrollBarVisibility="Hidden"/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<ControlTemplate x:Key="ComboBoxEditableTemplate" TargetType="{x:Type ComboBox}">
<Grid x:Name="templateRoot" SnapsToDevicePixels="true">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition MinWidth="{DynamicResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}" Width="0"/>
</Grid.ColumnDefinitions>
<Popup x:Name="PART_Popup" AllowsTransparency="true" Grid.ColumnSpan="2" IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}" PopupAnimation="{DynamicResource {x:Static SystemParameters.ComboBoxPopupAnimationKey}}" Placement="Bottom">
<Themes:SystemDropShadowChrome x:Name="shadow" Color="Transparent" MaxHeight="{TemplateBinding MaxDropDownHeight}" MinWidth="{Binding ActualWidth, ElementName=templateRoot}">
<Border x:Name="dropDownBorder" BorderBrush="{DynamicResource {x:Static SystemColors.WindowFrameBrushKey}}" BorderThickness="1" Background="{DynamicResource {x:Static SystemColors.WindowBrushKey}}">
<ScrollViewer x:Name="DropDownScrollViewer">
<Grid x:Name="grid" RenderOptions.ClearTypeHint="Enabled">
<Canvas x:Name="canvas" HorizontalAlignment="Left" Height="0" VerticalAlignment="Top" Width="0">
<Rectangle x:Name="opaqueRect" Fill="{Binding Background, ElementName=dropDownBorder}" Height="{Binding ActualHeight, ElementName=dropDownBorder}" Width="{Binding ActualWidth, ElementName=dropDownBorder}"/>
</Canvas>
<ItemsPresenter x:Name="ItemsPresenter" KeyboardNavigation.DirectionalNavigation="Contained" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Grid>
</ScrollViewer>
</Border>
</Themes:SystemDropShadowChrome>
</Popup>
<ToggleButton x:Name="toggleButton" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.ColumnSpan="2" IsChecked="{Binding IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ComboBoxToggleButton}"/>
<Border x:Name="border" Background="{StaticResource TextBox.Static.Background}" Margin="{TemplateBinding BorderThickness}">
<TextBox x:Name="PART_EditableTextBox" HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}" IsReadOnly="{Binding IsReadOnly, RelativeSource={RelativeSource TemplatedParent}}" Margin="{TemplateBinding Padding}" Style="{StaticResource ComboBoxEditableTextBox}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Opacity" TargetName="border" Value="0.56"/>
</Trigger>
<Trigger Property="IsKeyboardFocusWithin" Value="true">
<Setter Property="Foreground" Value="Black"/>
</Trigger>
<Trigger Property="HasDropShadow" SourceName="PART_Popup" Value="true">
<Setter Property="Margin" TargetName="shadow" Value="0,0,5,5"/>
<Setter Property="Color" TargetName="shadow" Value="#71000000"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Height" TargetName="dropDownBorder" Value="95"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
<Trigger Property="ScrollViewer.CanContentScroll" SourceName="DropDownScrollViewer" Value="false">
<Setter Property="Canvas.Top" TargetName="opaqueRect" Value="{Binding VerticalOffset, ElementName=DropDownScrollViewer}"/>
<Setter Property="Canvas.Left" TargetName="opaqueRect" Value="{Binding HorizontalOffset, ElementName=DropDownScrollViewer}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
<Style x:Key="ComboBoxStyle1" TargetType="{x:Type ComboBox}">
<Setter Property="FocusVisualStyle" Value="{StaticResource FocusVisual}"/>
<Setter Property="Background" Value="{StaticResource ComboBox.Static.Background}"/>
<Setter Property="BorderBrush" Value="{StaticResource ComboBox.Static.Border}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<Setter Property="Padding" Value="6,3,5,3"/>
<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
<Setter Property="ScrollViewer.PanningMode" Value="Both"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="Template" Value="{StaticResource ComboBoxTemplate}"/>
<Style.Triggers>
<Trigger Property="IsEditable" Value="true">
<Setter Property="IsTabStop" Value="false"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="Template" Value="{StaticResource ComboBoxEditableTemplate}"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
<ComboBox x:Name="Myc" Height="40" BorderThickness="3" BorderBrush="{x:Null}" Style="{DynamicResource ComboBoxStyle1}"/>
Previously Border named templateRoot's BorderBrush property set as
<Border x:Name="templateRoot" BorderBrush="{StaticResource ComboBox.Static.Border}".... />
now that was changed to TemplateBinding.

How to customize the WPF Ribbon 4.5 (styles, templates, etc.)

I try to customize System.Windows.Controls.Ribbon from the .Net Framework 4.5 so it can be used with the Expression Dark theme (dark colors like in default theme of the Blend).
I've tried following ideas, but until now without any progress:
change the Background of the ribbon: will change only the main
Color, but leaves all other glossy colors, highlight colos etc.
change the styles and templates: I couldn't find any default templates for the
Ribbon 4.5. I've tried to get them via Tools like ShowMeTheTemplate,
but it seems that they use some internal classes.
customizing the templates with Blend for VS2012: I get always an error "Copy Template failed."
use the .net 4 ribbon from the RibbonControlLibrary: the RibbonWindow
Looks ugly in the Windows 8 (see WPF RibbonWindow + Windows 8 -
control box looks bad), that I can't solve
Any help would be appreciated, all suggestions are welcome.

I was able to extract a fully working template using Show me the templates. To do that I modified it to extract templates from "System.Windows.Controls.Ribbon" (rather than the main framework assembly).
It gives me the following:
https://gist.github.com/drayde/75526b570a266f5f8f38 (too long to paste here)
Just add this to your resources and use it like this:
<Ribbon Template="{StaticResource ribbonTemplate}">
...
</Ribbon>
By modifying the template you should have full control over how your ribbon is displayed.

You can change a couple of colors by setting properties on the ribbon:
<ribbon:Ribbon x:Name="Ribbon"
Background="Khaki"
BorderBrush="Brown"
MouseOverBackground="LightCoral"
MouseOverBorderBrush="Coral"
PressedBackground="LightGreen"
PressedBorderBrush="Green"
CheckedBackground="LightBlue"
CheckedBorderBrush="Blue"
FocusedBackground="LightSlateGray"
FocusedBorderBrush="SlateBlue">
Not exactly a good-looking example, but shows how to do it.
Would be interested how to do a complete re-styling as well...

I followed this answer to get a template from VS.
It failed in a similar fashion as OP described.
Then I patched-in the missing parts {Binding (0)} using the gist from #Andreas.
To test, I set all the color properties to black in my view, and 50% magenta in the newly created template.
About this time I am ready to give up on System.Controls.Windows.Ribbon and try Fluent.Ribbon...
Template:
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:mwt="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Classic"
xmlns:swcrp="clr-namespace:System.Windows.Controls.Ribbon.Primitives;assembly=System.Windows.Controls.Ribbon"
xmlns:s="clr-namespace:System;assembly=mscorlib">
<!-- Template Colors -->
<SolidColorBrush x:Key="GroupsInnerBorderBrush" Color="#60FFFFFF"/>
<SolidColorBrush x:Key="QatTopHostBorderBrush1" Color="#66CCCCCC"/>
<SolidColorBrush x:Key="QatTopHostBorderBrush2" Color="#77222222"/>
<SolidColorBrush x:Key="QatTopHostBorderBrush3" Color="#81444444"/>
<SolidColorBrush x:Key="QatTopHostBorderBrush4" Color="#69EEEEEE"/>
<!-- #71000000 -->
<s:Byte x:Key="r">#00</s:Byte>
<s:Byte x:Key="g">#00</s:Byte>
<s:Byte x:Key="b">#00</s:Byte>
<s:Byte x:Key="a">#71</s:Byte>
<Color x:Key="DropShadowColor" R="{StaticResource r}" G="{StaticResource g}" B="{StaticResource b}" A="{StaticResource a}"/>
<LinearGradientBrush x:Key="GroupsBorderBackgroundBrush" EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#EEFFFFFF" Offset="0"/>
<GradientStop Color="#BBFFFFFF" Offset="0.1"/>
<GradientStop Color="#05FFFFFF" Offset="0.5"/>
<GradientStop Color="#20FFFFFF" Offset="1"/>
</LinearGradientBrush>
<LinearGradientBrush x:Key="TitleBarBackgroundBrush" EndPoint="0.5,1" StartPoint="0.5,0">
<GradientStop Color="#EEFFFFFF" Offset="0"/>
<GradientStop Color="#BBFFFFFF" Offset="0.1"/>
<GradientStop Color="#05FFFFFF" Offset="0.5"/>
<GradientStop Color="#20FFFFFF" Offset="1"/>
</LinearGradientBrush>
<!-- Template -->
<ControlTemplate x:Key="RibbonTemplate" TargetType="{x:Type Ribbon}">
<Grid SnapsToDevicePixels="True">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<Border x:Name="BackgroundBorder" Grid.ColumnSpan="3" Grid.Row="1" Grid.RowSpan="3"
BorderBrush="{TemplateBinding BorderBrush}"
Background="{TemplateBinding Background}"/>
<Border Grid.ColumnSpan="3" Grid.Row="1">
<Popup x:Name="PART_ITEMSPRESENTERPOPUP" AllowsTransparency="True"
IsOpen="{Binding IsDropDownOpen, RelativeSource={RelativeSource TemplatedParent}}"
PopupAnimation="{DynamicResource {x:Static SystemParameters.MenuPopupAnimationKey}}">
<mwt:SystemDropShadowChrome x:Name="Shdw" Color="Transparent" RenderOptions.ClearTypeHint="Enabled"
FocusVisualStyle="{x:Null}" Focusable="True" Margin="0,0,5,5">
<Border x:Name="CollapsedPopupBackgroundBorder" Background="{TemplateBinding Background}">
<ContentControl x:Name="popupItemsPresenterHost" KeyboardNavigation.DirectionalNavigation="Cycle"
Focusable="False" Margin="0,1,0,0" KeyboardNavigation.TabNavigation="Cycle"/>
</Border>
</mwt:SystemDropShadowChrome>
</Popup>
</Border>
<ContentControl x:Name="mainItemsPresenterHost" Grid.ColumnSpan="3" Focusable="False" Grid.Row="2">
<Border x:Name="groupsBorder" BorderThickness="1,0,1,1" Height="91" SnapsToDevicePixels="True"
BorderBrush="{TemplateBinding BorderBrush}"
Background="{StaticResource GroupsBorderBackgroundBrush}">
<Border BorderThickness="0,0,0,1" Margin="0,0,0,1" SnapsToDevicePixels="True"
BorderBrush="{StaticResource GroupsInnerBorderBrush}">
<ItemsPresenter x:Name="ItemsPresenter"/>
</Border>
</Border>
</ContentControl>
<Border x:Name="QatBottomHost" Grid.ColumnSpan="3" Grid.Row="3" BorderBrush="{TemplateBinding BorderBrush}">
<ContentPresenter x:Name="QatBottomHostContentPresenter" IsHitTestVisible="True"
HorizontalAlignment="Left" VerticalAlignment="Center"/>
</Border>
<Border x:Name="titleBarBackground" BorderThickness="0,0,0,1" Grid.ColumnSpan="3" Visibility="Collapsed"
BorderBrush="{TemplateBinding BorderBrush}"
Background="{StaticResource TitleBarBackgroundBrush}"/>
<DockPanel Grid.ColumnSpan="3" Grid.Column="0" Height="22" LastChildFill="True">
<ContentControl x:Name="windowButtonPlaceHolder" DockPanel.Dock="Right" Focusable="False"
IsHitTestVisible="False" Margin="3,0,0,0" Width="35">
<ContentControl.Visibility>
<TemplateBinding Property="IsHostedInRibbonWindow">
<TemplateBindingExtension.Converter>
<BooleanToVisibilityConverter />
</TemplateBindingExtension.Converter>
</TemplateBinding>
</ContentControl.Visibility>
</ContentControl>
<ContentControl x:Name="windowIconPadding" DockPanel.Dock="Left" Focusable="False"
IsHitTestVisible="False" Margin="0,0,3,0" Width="16"/>
<swcrp:RibbonTitlePanel x:Name="PART_TitlePanel">
<Grid x:Name="QatTopHost">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="Auto"/>
</Grid.ColumnDefinitions>
<Border x:Name="QatTopHostLeftBorder" BorderBrush="{StaticResource QatTopHostBorderBrush1}"
BorderThickness="1,0,1,0.9" Background="{StaticResource QatTopHostBorderBrush2}" Grid.Column="0"
CornerRadius="0,0,2,2" Margin="8,2,0,2" Width="3"/>
<ContentPresenter x:Name="QatTopHostContentPresenter" Grid.Column="1" IsHitTestVisible="True"
Content="{TemplateBinding QuickAccessToolBar}"/>
<Border x:Name="QatTopHostRightBorder" BorderBrush="{StaticResource QatTopHostBorderBrush1}"
BorderThickness="1,0,1,0.9" Background="{StaticResource QatTopHostBorderBrush2}" Grid.Column="2"
CornerRadius="0,0,2,2" Margin="0,2,1,2" Width="3"/>
</Grid>
<ContentPresenter x:Name="PART_TitleHost" ContentTemplate="{TemplateBinding TitleTemplate}"
Content="{TemplateBinding Title}" ContentSource="Title"
TextElement.Foreground="{DynamicResource {x:Static SystemColors.ActiveCaptionTextBrushKey}}"
TextElement.FontWeight="{DynamicResource {x:Static SystemFonts.CaptionFontWeightKey}}"
TextElement.FontSize="{DynamicResource {x:Static SystemFonts.CaptionFontSizeKey}}"
TextElement.FontFamily="{DynamicResource {x:Static SystemFonts.CaptionFontFamilyKey}}"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
IsHitTestVisible="False" Margin="3,0" MinWidth="75" MinHeight="22">
<ContentPresenter.Resources>
<DataTemplate x:Key="{DataTemplateKey DataType={x:Type s:String}}" DataType="{x:Type s:String}">
<TextBlock x:Name="titleTextBlock" HorizontalAlignment="{TemplateBinding HorizontalAlignment}"
Margin="0,-2,0,0" Text="{TemplateBinding Content}" TextTrimming="CharacterEllipsis"/>
<DataTemplate.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=(SystemParameters.IsGlassEnabled)}" Value="True"/>
<Condition Binding="{Binding IsHostedInRibbonWindow, RelativeSource={RelativeSource FindAncestor,
AncestorLevel=1, AncestorType={x:Type Ribbon}}}" Value="True"/>
</MultiDataTrigger.Conditions>
<Setter Property="Effect" TargetName="titleTextBlock">
<Setter.Value>
<DropShadowEffect BlurRadius="5" Color="White" ShadowDepth="0"/>
</Setter.Value>
</Setter>
</MultiDataTrigger>
<DataTrigger Binding="{Binding Path=(SystemParameters.IsGlassEnabled)}" Value="False">
<Setter Property="Margin" TargetName="titleTextBlock" Value="0"/>
<Setter Property="VerticalAlignment" TargetName="titleTextBlock" Value="Center"/>
</DataTrigger>
<DataTrigger Binding="{Binding Path=(SystemParameters.HighContrast)}" Value="True">
<Setter Property="Margin" TargetName="titleTextBlock" Value="0,1,0,0"/>
</DataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=(SystemParameters.UxThemeName)}" Value="AeroLite"/>
<Condition Binding="{Binding Path=(SystemParameters.IsGlassEnabled)}" Value="False"/>
<Condition Binding="{Binding IsHostedInRibbonWindow, RelativeSource={RelativeSource FindAncestor,
AncestorLevel=1, AncestorType={x:Type Ribbon}}}" Value="True"/>
<Condition Binding="{Binding WindowState, RelativeSource={RelativeSource FindAncestor,
AncestorLevel=1, AncestorType={x:Type RibbonWindow}}}" Value="Normal"/>
</MultiDataTrigger.Conditions>
<Setter Property="Margin" TargetName="titleTextBlock" Value="0,0,0,7"/>
</MultiDataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
</ContentPresenter.Resources>
</ContentPresenter>
<RibbonContextualTabGroupItemsControl x:Name="PART_ContextualTabGroupItemsControl"
HorizontalAlignment="Center" IsHitTestVisible="True"
WindowChrome.IsHitTestVisibleInChrome="True"/>
</swcrp:RibbonTitlePanel>
</DockPanel>
<ContentPresenter x:Name="applicationMenu" Content="{TemplateBinding ApplicationMenu}" Grid.Row="1" VerticalAlignment="Top"/>
<RibbonTabHeaderItemsControl x:Name="TabHeaderItemsControl" Grid.Column="1"
HorizontalAlignment="Left" Margin="1,1,1,0" Grid.Row="1" VerticalAlignment="Top"/>
<ContentPresenter x:Name="PART_HelpPane" ContentTemplate="{TemplateBinding HelpPaneContentTemplate}"
Content="{TemplateBinding HelpPaneContent}" Grid.Column="2" ContentSource="HelpPaneContent"
HorizontalAlignment="Right" Grid.Row="1" VerticalAlignment="Top"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsCollapsed" Value="True">
<Setter Property="Visibility" TargetName="applicationMenu" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="QatBottomHost" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="QatTopHost" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="mainItemsPresenterHost" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="TabHeaderItemsControl" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="PART_HelpPane" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="PART_ContextualTabGroupItemsControl" Value="Collapsed"/>
<Setter Property="MinWidth" TargetName="PART_TitleHost" Value="0"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsCollapsed" Value="True"/>
<Condition Property="IsHostedInRibbonWindow" Value="False"/>
</MultiTrigger.Conditions>
<Setter Property="Visibility" Value="Collapsed"/>
</MultiTrigger>
<Trigger Property="ShowQuickAccessToolBarOnTop" Value="False">
<Setter Property="Content" TargetName="QatTopHostContentPresenter" Value="{x:Null}"/>
<Setter Property="Visibility" TargetName="QatTopHost" Value="Collapsed"/>
<Setter Property="Content" TargetName="QatBottomHostContentPresenter"
Value="{Binding QuickAccessToolBar, RelativeSource={RelativeSource TemplatedParent}}"/>
<Setter Property="BorderThickness" TargetName="BackgroundBorder" Value="0,0,0,1"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding QuickAccessToolBar.HasItems, RelativeSource={RelativeSource Self}}" Value="False"/>
<Condition Binding="{Binding QuickAccessToolBar.CustomizeMenuButton, RelativeSource={RelativeSource Self}}" Value="{x:Null}"/>
</MultiDataTrigger.Conditions>
<Setter Property="Visibility" TargetName="QatTopHost" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="QatBottomHost" Value="Collapsed"/>
</MultiDataTrigger>
<Trigger Property="IsMinimized" Value="True">
<Setter Property="Content" TargetName="mainItemsPresenterHost" Value="{x:Null}"/>
<Setter Property="Visibility" TargetName="mainItemsPresenterHost" Value="Collapsed"/>
<Setter Property="Content" TargetName="popupItemsPresenterHost" Value="{Binding ElementName=groupsBorder}"/>
<Setter Property="BorderThickness" TargetName="BackgroundBorder" Value="0,0,0,1"/>
</Trigger>
<Trigger Property="WindowIconVisibility" Value="Collapsed">
<Setter Property="Visibility" TargetName="windowIconPadding" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="QatTopHostLeftBorder" Value="Collapsed"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsMinimized" Value="True"/>
<Condition Property="ShowQuickAccessToolBarOnTop" Value="False"/>
</MultiTrigger.Conditions>
<Setter Property="BorderThickness" TargetName="QatBottomHost" Value="0,1,0,0"/>
</MultiTrigger>
<Trigger Property="IsHostedInRibbonWindow" Value="False">
<Setter Property="Grid.Row" TargetName="BackgroundBorder" Value="0"/>
<Setter Property="Grid.RowSpan" TargetName="BackgroundBorder" Value="4"/>
<Setter Property="Visibility" TargetName="titleBarBackground" Value="Visible"/>
<Setter Property="Visibility" TargetName="windowIconPadding" Value="Collapsed"/>
<Setter Property="Visibility" TargetName="QatTopHostLeftBorder" Value="Collapsed"/>
</Trigger>
<Trigger Property="IsDropDownOpen" Value="True">
<Setter Property="BorderThickness" TargetName="BackgroundBorder" Value="0"/>
</Trigger>
<Trigger Property="HasDropShadow" SourceName="PART_ITEMSPRESENTERPOPUP" Value="True">
<Setter Property="Color" TargetName="Shdw" Value="{StaticResource DropShadowColor}"/>
</Trigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsActive, RelativeSource={RelativeSource FindAncestor,
AncestorLevel=1, AncestorType={x:Type RibbonWindow}}}" Value="False"/>
<Condition Binding="{Binding Path=(SystemParameters.IsGlassEnabled)}" Value="False"/>
<Condition Binding="{Binding IsHostedInRibbonWindow, RelativeSource={RelativeSource Self}}" Value="True"/>
</MultiDataTrigger.Conditions>
<Setter Property="TextElement.Foreground" TargetName="PART_TitleHost"
Value="{DynamicResource {x:Static SystemColors.InactiveCaptionTextBrushKey}}"/>
</MultiDataTrigger>
<DataTrigger Binding="{Binding Path=(SystemParameters.UxThemeName)}" Value="Aero">
<Setter Property="Margin" TargetName="QatTopHost" Value="0,-3,0,0"/>
<Setter Property="Margin" TargetName="QatTopHostLeftBorder" Value="3,3,0,5"/>
<Setter Property="Background" TargetName="QatTopHostLeftBorder" Value="{StaticResource QatTopHostBorderBrush3}"/>
<Setter Property="BorderBrush" TargetName="QatTopHostLeftBorder" Value="{StaticResource QatTopHostBorderBrush4}"/>
<Setter Property="Margin" TargetName="QatTopHostRightBorder" Value="0,3,1,5"/>
<Setter Property="Background" TargetName="QatTopHostRightBorder" Value="{StaticResource QatTopHostBorderBrush3}"/>
<Setter Property="BorderBrush" TargetName="QatTopHostRightBorder" Value="{StaticResource QatTopHostBorderBrush4}"/>
</DataTrigger>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=(SystemParameters.UxThemeName)}" Value="Aero"/>
<Condition Binding="{Binding WindowState, RelativeSource={RelativeSource FindAncestor,
AncestorLevel=1, AncestorType={x:Type RibbonWindow}}}" Value="Maximized"/>
</MultiDataTrigger.Conditions>
<Setter Property="Margin" TargetName="QatTopHost" Value="0"/>
</MultiDataTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>