Get Header name - wpf

Question

Hello I am a bit lost with the control Templates, I have an expander and some control-styles that apply onto the Expander.
So the idea is to let the User insert the header
<Expander Name="MyExpanderExpander" Style="{StaticResource MyExpanderNewGeneration}" Header="UserChoice" OverridesDefaultStyle="True" VerticalAlignment="Top" Margin="0,0,0,0" Height="210">
So now the Style : MyExpanderNewGeneration should get the header Name : UserChoic
The ToggleButton has to get the Header Name : UserChoice and here is my problem ..but how to do it?
my Style applying is
<Style TargetType="Expander" x:Key="MyExpanderNewGeneration" BasedOn="{StaticResource BaseControlStyle}" >
<!--x:Key="GroupBoxStyle"-->
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="Expander">
<Grid>
<!--Grid Rows split the GroupBox into two areas -->
<Grid.RowDefinitions>
<RowDefinition Height="30"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!--Header area-->
<Border Name="HeaderArea"
Grid.Row="0"
Background="Transparent"
BorderBrush="Transparent"
BorderThickness="1"
CornerRadius="2,2,0,0" >
<ToggleButton x:Name="ExpanderButton"
Grid.Row="0"
Grid.Column="0"
Margin="0,0,0,0"
VerticalAlignment="Top"
Template="{StaticResource TestToggleButton}"
Content="{TemplateBinding Header}"
IsChecked="{Binding Path=IsExpanded, RelativeSource={RelativeSource TemplatedParent}}"
OverridesDefaultStyle="True">
</ToggleButton>
Herer I want to get the UserChoice Name.
<ControlTemplate x:Key="TestToggleButton" TargetType="{x:Type ToggleButton}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="300"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Label Foreground="White" Width="300" Grid.Column="0" FontSize="15"
HorizontalAlignment="Left" FontWeight="Normal" Something={HEADER???}
How to solve this?

Answer 1

Since you are setting Content="{TemplateBinding Header}" in your ExpanderButton, you will need to bind to the Content property inside your TestToggleButton style's control template:
<ControlTemplate x:Key="TestToggleButton" TargetType="{x:Type ToggleButton}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="300"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Label
...
Content={TemplateBinding Content} />
...
</Grid>
</ControlTemplate>