I have an Expander with Expand Direction right. This works fine but I would like to have the content still appear under the Expander Button and Header. Also I would like to have these, the Button and Header, still appear on the same line. What would be the best way of doing this?
<Expander Header="Test" ExpandDirection="Right">
<ListBox VerticalAlignment="Top" MaxHeight="400" Name="lbxTest"/>
</Expander>
You need to re-template the entire Expander control. You can right-click on the Expander in design mode in Visual Studio or in Blend and select Edit Template->Edit a Copy to copy the default template into your XAML markup and then edit it as per your requirements:
<Expander Header="Test" ExpandDirection="Right">
<Expander.Resources>
<SolidColorBrush x:Key="Expander.MouseOver.Circle.Stroke" Color="#FF5593FF"/>
<SolidColorBrush x:Key="Expander.MouseOver.Circle.Fill" Color="#FFF3F9FF"/>
<SolidColorBrush x:Key="Expander.MouseOver.Arrow.Stroke" Color="#FF000000"/>
<SolidColorBrush x:Key="Expander.Pressed.Circle.Stroke" Color="#FF3C77DD"/>
<SolidColorBrush x:Key="Expander.Pressed.Circle.Fill" Color="#FFD9ECFF"/>
<SolidColorBrush x:Key="Expander.Pressed.Arrow.Stroke" Color="#FF000000"/>
<SolidColorBrush x:Key="Expander.Disabled.Circle.Stroke" Color="#FFBCBCBC"/>
<SolidColorBrush x:Key="Expander.Disabled.Circle.Fill" Color="#FFE6E6E6"/>
<SolidColorBrush x:Key="Expander.Disabled.Arrow.Stroke" Color="#FF707070"/>
<SolidColorBrush x:Key="Expander.Static.Circle.Fill" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="Expander.Static.Circle.Stroke" Color="#FF333333"/>
<SolidColorBrush x:Key="Expander.Static.Arrow.Stroke" Color="#FF333333"/>
<Style x:Key="ExpanderRightHeaderStyle" TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Padding="{TemplateBinding Padding}">
<Grid Background="Transparent" SnapsToDevicePixels="False">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Grid>
<Grid.LayoutTransform>
<TransformGroup>
<TransformGroup.Children>
<TransformCollection>
<RotateTransform Angle="-90"/>
</TransformCollection>
</TransformGroup.Children>
</TransformGroup>
</Grid.LayoutTransform>
<Ellipse x:Name="circle" Fill="{StaticResource Expander.Static.Circle.Fill}" HorizontalAlignment="Center" Height="19" Stroke="{StaticResource Expander.Static.Circle.Stroke}" VerticalAlignment="Center" Width="19"/>
<Path x:Name="arrow" Data="M 1,1.5 L 4.5,5 L 8,1.5" HorizontalAlignment="Center" SnapsToDevicePixels="false" Stroke="{StaticResource Expander.Static.Arrow.Stroke}" StrokeThickness="2" VerticalAlignment="Center"/>
</Grid>
<ContentPresenter HorizontalAlignment="Center" Margin="4,4,0,0" Grid.Column="1" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Center"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="true">
<Setter Property="Data" TargetName="arrow" Value="M 1,4.5 L 4.5,1 L 8,4.5"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="true">
<Setter Property="Stroke" TargetName="circle" Value="{StaticResource Expander.MouseOver.Circle.Stroke}"/>
<Setter Property="Fill" TargetName="circle" Value="{StaticResource Expander.MouseOver.Circle.Fill}"/>
<Setter Property="Stroke" TargetName="arrow" Value="{StaticResource Expander.MouseOver.Arrow.Stroke}"/>
</Trigger>
<Trigger Property="IsPressed" Value="true">
<Setter Property="Stroke" TargetName="circle" Value="{StaticResource Expander.Pressed.Circle.Stroke}"/>
<Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
<Setter Property="Fill" TargetName="circle" Value="{StaticResource Expander.Pressed.Circle.Fill}"/>
<Setter Property="Stroke" TargetName="arrow" Value="{StaticResource Expander.Pressed.Arrow.Stroke}"/>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Stroke" TargetName="circle" Value="{StaticResource Expander.Disabled.Circle.Stroke}"/>
<Setter Property="Fill" TargetName="circle" Value="{StaticResource Expander.Disabled.Circle.Fill}"/>
<Setter Property="Stroke" TargetName="arrow" Value="{StaticResource Expander.Disabled.Arrow.Stroke}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Expander.Resources>
<Expander.Template>
<ControlTemplate TargetType="{x:Type Expander}">
<Border BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Background="{TemplateBinding Background}"
CornerRadius="3" SnapsToDevicePixels="true">
<Grid>
<Grid.RowDefinitions>
<RowDefinition />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<ToggleButton x:Name="HeaderSite" ContentTemplate="{TemplateBinding HeaderTemplate}" ContentTemplateSelector="{TemplateBinding HeaderTemplateSelector}" Content="{TemplateBinding Header}" Foreground="{TemplateBinding Foreground}" FontWeight="{TemplateBinding FontWeight}"
FontStyle="{TemplateBinding FontStyle}" FontStretch="{TemplateBinding FontStretch}"
FontSize="{TemplateBinding FontSize}" FontFamily="{TemplateBinding FontFamily}"
HorizontalContentAlignment="{TemplateBinding HorizontalContentAlignment}"
IsChecked="{Binding IsExpanded, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}"
Margin="1" MinWidth="0" MinHeight="0" Padding="{TemplateBinding Padding}"
Style="{StaticResource ExpanderRightHeaderStyle}"
VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}"
HorizontalAlignment="Left">
<ToggleButton.FocusVisualStyle>
<Style>
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Border>
<Rectangle Margin="0" SnapsToDevicePixels="true" Stroke="Black" StrokeThickness="1" StrokeDashArray="1 2"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ToggleButton.FocusVisualStyle>
</ToggleButton>
<ContentPresenter x:Name="ExpandSite" Grid.Row="1" Focusable="false" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" Visibility="Collapsed" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="true">
<Setter Property="Visibility" TargetName="ExpandSite" Value="Visible"/>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Expander.Template>
<ListBox VerticalAlignment="Top" MaxHeight="400" Name="lbxTest"/>
</Expander>
And no, there is no easier way of doing this :)