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WPF Panel where only one item is visible at a time (alternative to QML's StackLayout)?

I have several controls and I want to show them only one at a time.
In QML there is a type StackLayout which does that. But I haven't found a similar control in WPF.
I want to achieve the following:
<controls:StackLayout ControlIndex="{Binding CurrentlyVisibleControlIndex}">
<controls:MyCustomControl1 />
<controls:MyCustomControl2 />
<TextBlock Text="Some text" />
<Grid/>
</controls:StackLayout>
Then, from my ViewModel I want to dynamically change which control is shown.
Answers:
Direct answer to my question
Better way of solving my problem

In this case, I would go with a ContentControl templated based on the type of content you give it in your view model (rather than based on index). As the property changes, the appropriate template will be selected and displayed.
XAML
Resources define data templates for each kind of content in the control
<Window.Resources>
<DataTemplate DataType="{x:Type local:ContentXyz}">
<controls:ControlXyz/>
</DataTemplate>
<DataTemplate DataType="{x:Type local:ContentAbc}">
<controls:ControlAbc/>
</DataTemplate>
</Window.Resources>
<ContentControl Content="{Binding Content}"/>
ViewModel
The Content property holds the view model for the active control. When user actions or data changes require to display a different control, set it to the appropriate view model.
public IContent Content
{
get => this.content;
set => this.SetProperty(ref this.content, value);
}
And viewmodel classes for your inner user controls need to implement IContent (which is just a marker interface to describe the view model can be used in this place).
More
Also, frameworks like Prism help you compose views in more complex ways, giving you tools like automatic view discovery - see their documentation for more.

But, I'm afraid that "abusing" ListBox for achieving my goal is not a good idea, because ListBox handles "Ctrl+LeftMouseCLick" which will deselect the item.
The ListBox needs to be hidden. It will not render.
Only its SelecteItem will be rendered.
Example for explanation:
<Window x:Class="StackLayout.StackLayoutWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:StackLayout"
mc:Ignorable="d"
Title="StackLayoutWindow" Height="450" Width="800">
<Grid >
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBlock Text="Enter the index:" Margin="5"/>
<TextBox x:Name="textBox" Grid.Column="1" Text="1" Margin="5"
HorizontalContentAlignment="Center"/>
<TextBlock Grid.Row="1" Text="Selected Item:" Margin="5" VerticalAlignment="Center"/>
<ListBox x:Name="listBox"
SelectedIndex="{Binding Text, ElementName=textBox, Mode=OneWay}"
Visibility="Collapsed">
<TextBlock Text="TextBlock" FontSize="20"/>
<Button Content="Click me!" Padding="15 5"/>
<Border Background="Blue" Width="100" Height="100"/>
<Label Content="Label" BorderBrush="SkyBlue" BorderThickness="5"/>
</ListBox>
<ContentPresenter Grid.Row="1" Grid.Column="1"
Content="{Binding SelectedItem, ElementName=listBox}"
VerticalAlignment="Center" HorizontalAlignment="Center" />
</Grid>
</Window>
Do you know if it is possible to create a custom user control which will contain the list and ContentPresenter so it can be used in the way I specified in my question?
In this case (as far as I understood the task), it makes no sense.
It is enough to override the default ListBox template.
In the example, to shorten the code, the template is specified in the Window resources.
But it is better to transfer it to the dictionary and connect it to the App.
<Window x:Class="StackLayout.StackLayoutTemplateWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:StackLayout"
mc:Ignorable="d"
Title="StackLayoutTemplateWindow" Height="450" Width="800">
<FrameworkElement.Resources>
<SolidColorBrush x:Key="ListBox.Static.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ListBox.Static.Border" Color="#FFABADB3"/>
<SolidColorBrush x:Key="ListBox.Disabled.Background" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="ListBox.Disabled.Border" Color="#FFD9D9D9"/>
<Style x:Key="ListBoxStyle.StackLayout" TargetType="{x:Type ListBox}">
<Setter Property="Background" Value="{StaticResource ListBox.Static.Background}"/>
<Setter Property="BorderBrush" Value="{StaticResource ListBox.Static.Border}"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
<Setter Property="ScrollViewer.PanningMode" Value="Both"/>
<Setter Property="Stylus.IsFlicksEnabled" Value="False"/>
<Setter Property="VerticalContentAlignment" Value="Center"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ListBox}">
<Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Padding="1" SnapsToDevicePixels="true">
<!--<ScrollViewer Focusable="false" Padding="{TemplateBinding Padding}">
<ItemsPresenter SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</ScrollViewer>-->
<ContentPresenter Content="{TemplateBinding SelectedItem}"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Background" TargetName="Bd" Value="{StaticResource ListBox.Disabled.Background}"/>
<Setter Property="BorderBrush" TargetName="Bd" Value="{StaticResource ListBox.Disabled.Border}"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsGrouping" Value="true"/>
<Condition Property="VirtualizingPanel.IsVirtualizingWhenGrouping" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</MultiTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</FrameworkElement.Resources>
<Grid >
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition/>
</Grid.ColumnDefinitions>
<TextBlock Text="Enter the index:" Margin="5"/>
<TextBox x:Name="textBox" Grid.Column="1" Text="1" Margin="5"
HorizontalContentAlignment="Center"/>
<TextBlock Grid.Row="1" Text="Selected Item:" Margin="5" VerticalAlignment="Center"/>
<ListBox x:Name="listBox"
SelectedIndex="{Binding Text, ElementName=textBox, Mode=OneWay}"
Style="{DynamicResource ListBoxStyle.StackLayout}"
Grid.Row="1" Grid.Column="1"
VerticalAlignment="Center" HorizontalAlignment="Center">
<TextBlock Text="TextBlock" FontSize="20"/>
<Button Content="Click me!" Padding="15 5"/>
<Border Background="Blue" Width="100" Height="100"/>
<Label Content="Label" BorderBrush="SkyBlue" BorderThickness="5"/>
</ListBox>
</Grid>
</Window>
Optionally, you can easily create a Custom Control from the ListBox with this template.
Although I do not see the point in this.

Thanks to #EldHasp's answer I have found a much simpler solution:
<ListBox x:Class="MyProject.StackLayout"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<ListBox.Template>
<ControlTemplate TargetType="{x:Type ListBox}">
<ContentPresenter Content="{TemplateBinding SelectedItem}"/>
</ControlTemplate>
</ListBox.Template>
</ListBox>
And it can be used in the following way:
<controls:StackLayout SelectedIndex="{Binding CurrentlyVisibleControlIndex}">
<controls:MyCustomControl1 />
<controls:MyCustomControl2 />
<TextBlock Text="Some text" />
<Grid/>
</controls:StackLayout>

By the way, using the way you have proposed I have found that it is possible to implement the StackLayout much simpler
You can think of many options for implementation.
WPF is a very flexible tool.
And the task itself is relatively simple.
Here's an example of a Sharpe implementation:
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Media;
namespace StackLayout
{
public class StackLayout : ListBox
{
public StackLayout()
=> Loaded += OnStackLayoutLoaded;
public static void OnStackLayoutLoaded(object sender, RoutedEventArgs e)
{
ListBox listBox = (ListBox)sender;
Border border = (Border)VisualTreeHelper.GetChild(listBox, 0);
ContentPresenter presenter = new ContentPresenter();
Binding snapsToDevicePixelsBinding = new Binding()
{
Path = new PropertyPath(SnapsToDevicePixelsProperty),
Source = listBox
};
Binding selectedItemBinding = new Binding()
{
Path = new PropertyPath(SelectedItemProperty),
Source = listBox
};
presenter.SetBinding(SnapsToDevicePixelsProperty, snapsToDevicePixelsBinding);
presenter.SetBinding(ContentPresenter.ContentProperty, selectedItemBinding);
border.Child = presenter;
}
}
}
In my example, the default ListBox border is preserved, but if desired, you can also remove it.
BUT once again I would like to draw your attention to the fact that you have most likely chosen the wrong path for the realization of your task as a whole.

Style grid layout cover controls

I'm trying set backcolor for all grid layout in my project using resource dictionary. This is code of file where i modify my grid.
<ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="clr-namespace:Theme">
<SolidColorBrush x:Key="GridBackColor" Color="Red"/>
<Style TargetType="Grid">
<Setter Property="Background" Value="{StaticResource GridBackColor}"/>
<Setter Property="Opacity" Value="0.5"/>
</Style>
</ResourceDictionary>
After set Background property all controls on grid were disappear, but when i set opacity i can only say that all controls are under grid layout and any mouse events not work.
Here how it's look like:
this is my window code.
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="10*"/>
<ColumnDefinition Width="125"/>
<ColumnDefinition Width="20"/>
<ColumnDefinition Width="125"/>
<ColumnDefinition Width="10*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="10*"/>
<RowDefinition Height="40"/>
<RowDefinition Height="40"/>
<RowDefinition Height="20"/>
<RowDefinition Height="30"/>
<RowDefinition Height="10*"/>
</Grid.RowDefinitions>
<Label Content="Name" Grid.Column="1" Grid.Row="1" Grid.ColumnSpan="3" FontSize="20"
HorizontalAlignment="Stretch" VerticalAlignment="Center"/>
<TextBox Name="TbName" Grid.Column="1" Grid.Row="2" Grid.ColumnSpan="3" FontSize="20"
HorizontalAlignment="Stretch" />
<Button Content="Add" Name="BtAdd" Grid.Column="1" Grid.Row="4" IsDefault="True"
HorizontalAlignment="Right" VerticalAlignment="Center" Width="100" Click="BtAdd_Click"/>
<Button Content="Close" Name="BtClose" Grid.Column="3" Grid.Row="4" IsCancel="True"
HorizontalAlignment="Left" Width="100" Click="BtClose_Click"/>
</Grid>

When you applied you style globally to all the Grids in your application, the ones used inside other controls will also be affected. For instance take a look at the Window control (from the vs designer, left click on the window > Edit Template > Edit a copy)
<Window.Resources>
<ControlTemplate x:Key="WindowTemplateKey" TargetType="{x:Type Window}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}">
<Grid>
<AdornerDecorator>
<ContentPresenter/>
</AdornerDecorator>
<ResizeGrip x:Name="WindowResizeGrip" HorizontalAlignment="Right" IsTabStop="false" Visibility="Collapsed" VerticalAlignment="Bottom"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="ResizeMode" Value="CanResizeWithGrip"/>
<Condition Property="WindowState" Value="Normal"/>
</MultiTrigger.Conditions>
<Setter Property="Visibility" TargetName="WindowResizeGrip" Value="Visible"/>
</MultiTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
<Style x:Key="WindowStyle1" TargetType="{x:Type Window}">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.WindowTextBrushKey}}"/>
<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type Window}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}">
<AdornerDecorator>
<ContentPresenter/>
</AdornerDecorator>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="ResizeMode" Value="CanResizeWithGrip">
<Setter Property="Template" Value="{StaticResource WindowTemplateKey}"/>
</Trigger>
</Style.Triggers>
</Style>
</Window.Resources>
Notice the Grid defined in the Border inside the ControlTemplate.
An easy fix to your issue is to assign a key to your style and assign it to the Grid manually:
<Style TargetType="Grid" x:Key="GridStyle">
<Setter Property="Background" Value="{StaticResource GridBackColor}"/>
<Setter Property="Opacity" Value="0.5"/>
</Style>
To use it:
<Grid Style="{StaticResource GridStyle}">
...
</Grid>

How to create a simple menu with labels on the left side with WPF?

I've been developing some simple apps (just for educational purposes) with Windows Forms and now I'm starting to learn WPF, but it seems a bit more complex to me.
I would like to create a simple menu like the one you can see in the pictures. I've been trying to find it on Google and YouTube, but I only found tutorials about "Hamburger menu", which isn't what I'm looking for.

This is really an area where WPF shines: the layout you describe can be implemented with nothing more than a restyled tab control.
Start with an unstyled tab control with TabStripPlacement of Left:
Then edit the TabControl style to add gradient and margins behind the TabPanel:
Add the image and override the TabItem style to set the font and remove the background. I used a chevron to indicate selection rather than bolding the text, but that would have been handled the same way.
Here is the full XAML used for the screenshots above:
<Window x:Class="StackOverflowTabControl.MainWindow"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
xmlns:local="clr-namespace:StackOverflowTabControl"
mc:Ignorable="d"
Title="MainWindow" Height="350" Width="525">
<Window.Resources>
<BooleanToVisibilityConverter x:Key="BooleanToVisibilityConverter"/>
<Style x:Key="ItemContainerStyle" TargetType="{x:Type TabItem}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TabItem}">
<Grid Margin="15,5">
<Path Width="10" Height="14" Margin="0,2,0,0" HorizontalAlignment="Left" VerticalAlignment="Center" Stretch="Fill" Fill="#FF000000" Data="F1 M 39.8307,37.6042L 36.6641,34.4375L 25.1849,23.3542L 35.4766,23.3542L 50.5182,37.6042L 35.4766,51.8542L 25.1849,51.8542L 36.6641,40.7708L 39.8307,37.6042 Z " Visibility="{Binding IsSelected, Converter={StaticResource BooleanToVisibilityConverter}, RelativeSource={RelativeSource TemplatedParent}}"/>
<ContentPresenter Content="{TemplateBinding Header}" Margin="20,5,10,5">
<ContentPresenter.Resources>
<Style TargetType="{x:Type TextBlock}">
<Setter Property="FontSize" Value="18" />
<Setter Property="FontWeight" Value="Light" />
</Style>
</ContentPresenter.Resources>
</ContentPresenter>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="TabControlStyle1" TargetType="{x:Type TabControl}">
<Setter Property="TabStripPlacement" Value="Left" />
<Setter Property="ItemContainerStyle" Value="{StaticResource ItemContainerStyle}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TabControl}">
<Grid x:Name="templateRoot" ClipToBounds="true" SnapsToDevicePixels="true" KeyboardNavigation.TabNavigation="Local">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="1*" />
</Grid.ColumnDefinitions>
<Border Grid.Column="0" Padding="5">
<Border.Background>
<LinearGradientBrush EndPoint="0,0" StartPoint="1,0">
<GradientStop Color="#FFC7C7C7" Offset="0"/>
<GradientStop Color="#FFECECEC" Offset="1"/>
</LinearGradientBrush>
</Border.Background>
<DockPanel>
<Image DockPanel.Dock="Bottom" HorizontalAlignment="Center" Margin="20" Source="pack://application:,,,/StackOverflowTabControl;component/twc.png" Width="200" />
<TabPanel x:Name="headerPanel" Background="Transparent" Grid.Column="0" IsItemsHost="true" Margin="2,2,2,0" Grid.Row="0" KeyboardNavigation.TabIndex="1" Panel.ZIndex="1"/>
</DockPanel>
</Border>
<Border x:Name="contentPanel" Grid.Column="1" Margin="5,0,0,0">
<ContentPresenter x:Name="PART_SelectedContentHost" ContentSource="SelectedContent" Margin="{TemplateBinding Padding}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<TabControl Style="{DynamicResource TabControlStyle1}">
<TabItem Header="System Information">
<TextBlock Text="Windows 10 pro" />
</TabItem>
<TabItem Header="Something else">
<TextBlock Text="Other page" />
</TabItem>
</TabControl>
</Grid>
</Window>

Base Expander Style, override header color

Is it possible to create some sort of base expander style and override the background color of the header in a derived style?
In my application I'm using expanders a lot and I would like to change the background color of the header. I know I could just copy&paste my style and edit the color, but it would be nicer to just create a new style based on the "base style" and setting the header's background color.
But I do not know how to access this color.
It's the color of this line: below I'd like to change (the border in the header): Border Name="border"... I cannot access "border" in the setter of the derived style...
This is my (base) style:
<Style TargetType="Expander" x:Key="ExpanderStyle">
<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextColor}}"/>
<Setter Property="Template">
<Setter.Value>
<!-- Control template for expander -->
<ControlTemplate TargetType="Expander" x:Name="exp">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Name="ContentRow" Height="0"/>
</Grid.RowDefinitions>
<Border Name="border" Grid.Row="0" Background="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}" BorderThickness="1" CornerRadius="4,4,0,0" >
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="20" />
</Grid.ColumnDefinitions>
<ToggleButton x:Name="tb" FontFamily="Marlett" FontSize="9.75" Background="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}" Foreground="Black" Grid.Column="1" Content="u" IsChecked="{Binding Path=IsExpanded,Mode=TwoWay,RelativeSource={RelativeSource TemplatedParent}}" />
<ContentPresenter x:Name="HeaderContent" Grid.Column="0" Margin="4" ContentSource="Header" RecognizesAccessKey="True" />
</Grid>
</Border>
<Border x:Name="Content" Grid.Row="1" BorderThickness="1,0,1,1" CornerRadius="0,0,4,4" >
<ContentPresenter Margin="4" />
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="True">
<Setter TargetName="ContentRow" Property="Height" Value="{Binding ElementName=Content,Path=Height}" />
<Setter Property="Content" TargetName="tb" Value="t"></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
I would like to do something like this:
<Style x:Key="ExpanderStyleRed" BasedOn="{StaticResource ExpanderStyle}" TargetType="Expander">
<Setter Property="???" Value="Red"/>
<Style>

Use TemplateBinding:
<Style TargetType="Expander" x:Key="ExpanderStyle">
<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextColor}}"/>
<Setter Property="Template">
<Setter.Value>
<!-- Control template for expander -->
<ControlTemplate TargetType="Expander" x:Name="exp">
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Name="ContentRow" Height="0"/>
</Grid.RowDefinitions>
<Border Name="border" Grid.Row="0" Background="{TemplateBinding Background}" BorderThickness="1" CornerRadius="4,4,0,0" >
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*" />
<ColumnDefinition Width="20" />
</Grid.ColumnDefinitions>
<ToggleButton x:Name="tb" FontFamily="Marlett" FontSize="9.75" Background="{DynamicResource {x:Static SystemColors.ControlDarkBrushKey}}" Foreground="Black" Grid.Column="1" Content="u" IsChecked="{Binding Path=IsExpanded,Mode=TwoWay,RelativeSource={RelativeSource TemplatedParent}}" />
<ContentPresenter x:Name="HeaderContent" Grid.Column="0" Margin="4" ContentSource="Header" RecognizesAccessKey="True" />
</Grid>
</Border>
<Border x:Name="Content" Grid.Row="1" BorderThickness="1,0,1,1" CornerRadius="0,0,4,4" >
<ContentPresenter Margin="4" />
</Border>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="True">
<Setter TargetName="ContentRow" Property="Height" Value="{Binding ElementName=Content,Path=Height}" />
<Setter Property="Content" TargetName="tb" Value="t"></Setter>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="ExpanderStyleRed" BasedOn="{StaticResource ExpanderStyle}" TargetType="Expander">
<Setter Property="Background" Value="#2fff0000"/>
</Style>
And then:
<Grid>
<Expander x:Name="expander1" Style="{DynamicResource ExpanderStyle}" Header="Expander" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="7,10,0,0" Height="108">
<TextBlock Width="250" Height="150" TextWrapping="Wrap">
asklsaklsa saaskklsaklas alsaklalkjd
asklsaklsaklsa saklsaklsakl jsajkjska
saklsaklsakl sasa
</TextBlock>
</Expander>
<Expander x:Name="expander2" Style="{DynamicResource ExpanderStyleRed}" Header="Expander" HorizontalAlignment="Left" VerticalAlignment="Top" Margin="12,126,0,0" Height="133">
<TextBlock Width="250" Height="150" TextWrapping="Wrap">
asklsaklsa saaskklsaklas alsaklalkjd
asklsaklsaklsa saklsaklsakl jsajkjska
saklsaklsakl sasa
</TextBlock>
</Expander>
</Grid>

DoubleUpDown custom style wpf

I want to make custom style for doubleupdown button like on example.
Example:
What i have
main problem is that <RepeatButton x:Name="PART_IncreaseButton" Grid.Row="0" IsTabStop="{TemplateBinding IsTabStop}" Style="{StaticResource CustomRepeatButtonStyle}"/> does not respond when i am clickin on it why?
Xaml code of me freak:
<Window.Resources>
<Style x:Key="CustomRepeatButtonStyle" TargetType="{x:Type RepeatButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type RepeatButton}">
<Grid x:Name="customgrid" Background="White">
<Polygon x:Name="custompolygon" Points="1,11 6,1 11,11" Fill="SkyBlue" VerticalAlignment="Center" HorizontalAlignment="Center">
</Polygon>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="true">
<Setter TargetName="custompolygon" Property="Fill" Value="black"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="CustomDoubleUpDownStyle" TargetType="{x:Type xctk:DoubleUpDown}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type xctk:DoubleUpDown}">
<Border BorderThickness="1" BorderBrush="Purple">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="0.3*"/>
<ColumnDefinition />
</Grid.ColumnDefinitions>
<Grid Grid.Column="0">
<Grid.RowDefinitions>
<RowDefinition/>
<RowDefinition/>
</Grid.RowDefinitions>
<RepeatButton x:Name="PART_IncreaseButton" Grid.Row="0" IsTabStop="{TemplateBinding IsTabStop}" Style="{StaticResource CustomRepeatButtonStyle}"/>
<RepeatButton x:Name="PART_DecreaseButton" Grid.Row="1" IsTabStop="{TemplateBinding IsTabStop}"/>
</Grid>
<ContentPresenter Grid.Column="1" Content="{TemplateBinding Property=Value}" HorizontalAlignment="Center" VerticalAlignment="Center"/>
</Grid>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Window.Resources>
<Grid>
<xctk:DoubleUpDown Width="180" Height="70" Style="{StaticResource CustomDoubleUpDownStyle}" Value="20"/>
</Grid>

In your XAML there are no functions bound to the click event (or any other event). In other words: From the programs point of view there is nothing to do, when any of your buttons get clicked. Is this your problem?
In this case add event handlers and modify the counter in your model accordingly.