I'm stuck with one very stupid problem - need to style selected row in WPF DataGrid.
I want to show a rectangle with blue border instead of just filling entire row with some color.
Any ideas how to implement this? It just must be some way to make it pretty easy.
Use CellStyle and RowStyle on DataGrid. DataGridCell and DataGridRow both have IsSelected property that can be used in a Trigger to find out if they are selected.
Something like following should do the trick:
<DataGrid.CellStyle>
<Style TargetType="DataGridCell">
<Style.Triggers>
<Trigger Property="IsSelected"
Value="True">
<Setter Property="Background"
Value="White" />
<Setter Property="Foreground"
Value="Black" />
</Trigger>
</Style.Triggers>
</Style>
</DataGrid.CellStyle>
<DataGrid.RowStyle>
<Style TargetType="DataGridRow">
<Style.Triggers>
<Trigger Property="IsSelected"
Value="True">
<Setter Property="BorderBrush"
Value="Blue" />
<Setter Property="BorderThickness"
Value="2" />
</Trigger>
</Style.Triggers>
</Style>
</DataGrid.RowStyle>
Just play around until you get it right.
I like this one:
<Style TargetType="{x:Type DataGridRow}">
<Setter Property="BorderBrush" Value="LightGray" />
<Setter Property="BorderThickness" Value="1" />
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="BorderBrush" Value="Blue" />
</Trigger>
</Style.Triggers>
<Style.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="Transparent" />
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightTextBrushKey}" Color="Black" />
</Style.Resources>
</Style>
try this
<DataGrid.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" Color="Transparent"/>
<Style TargetType="{x:Type DataGridRow}">
<Setter Property="HeaderStyle">
<Setter.Value>
<Style TargetType="{x:Type DataGridRowHeader}">
<Setter Property="Visibility" Value="Collapsed"/>
<Setter Property="Width" Value="0"/>
</Style>
</Setter.Value>
</Setter>
<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.WindowBrushKey}}"/>
<Setter Property="SnapsToDevicePixels" Value="true"/>
<Setter Property="Validation.ErrorTemplate" Value="{x:Null}"/>
<Setter Property="ValidationErrorTemplate">
<Setter.Value>
<ControlTemplate>
<TextBlock Foreground="Red" Margin="2,0,0,0" Text="!" VerticalAlignment="Center"/>
</ControlTemplate>
</Setter.Value>
</Setter>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type DataGridRow}">
<Border x:Name="DGR_Border" BorderThickness="1" CornerRadius="5" Background="{TemplateBinding Background}" SnapsToDevicePixels="True">
<SelectiveScrollingGrid>
<SelectiveScrollingGrid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</SelectiveScrollingGrid.ColumnDefinitions>
<Grid Grid.Column="1">
<Grid.RowDefinitions>
<RowDefinition Height="*"/>
<RowDefinition Height="Auto"/>
</Grid.RowDefinitions>
<DataGridCellsPresenter ItemsPanel="{TemplateBinding ItemsPanel}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
<DataGridDetailsPresenter Margin="4" Grid.Row="1" SelectiveScrollingGrid.SelectiveScrollingOrientation="{Binding AreRowDetailsFrozen, ConverterParameter={x:Static SelectiveScrollingOrientation.Vertical}, Converter={x:Static DataGrid.RowDetailsScrollingConverter}, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}" Visibility="{TemplateBinding DetailsVisibility}"/>
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Grid.RowSpan="2"/>
</Grid>
<DataGridRowHeader SelectiveScrollingGrid.SelectiveScrollingOrientation="Vertical" Visibility="{Binding HeadersVisibility, ConverterParameter={x:Static DataGridHeadersVisibility.Row}, Converter={x:Static DataGrid.HeadersVisibilityConverter}, RelativeSource={RelativeSource AncestorType={x:Type DataGrid}}}"/>
</SelectiveScrollingGrid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter TargetName="DGR_Border" Property="BorderBrush" Value="Blue"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="DetailsVisibility" Value="Visible">
<Setter Property="BorderThickness" Value="4,1,4,4"/>
<Setter Property="BorderBrush" Value="#FF3886B9"/>
</Trigger>
<!--<Trigger Property="IsSelected" Value="True">
<Setter Property="BorderBrush" Value="Blue"/>
</Trigger>-->
</Style.Triggers>
</Style>
</DataGrid.Resources>
Related
I'm using WPF 4.5.2
My basic structure looks like this
<UserControl>
<Grid>
<ContentPresenter />
</Grid>
</UserControl>
At runtime the ContentPresenter hosts a TreeView, for example
<TreeView>
<TreeViewItem Header="Node 1">
<TreeViewItem Header="Leaf 1" />
<TreeViewItem Header="Leaf 2" />
</TreeViewItem>
<TreeViewItem Header="Node 2" />
</TreeView>
I want the TreeViewItems which header says Node sth. to be stretched to the width of the parent UserControl.
Unfortunately, the TreeView itself is strechted to width of the application window.
How do I have to set width in the style for the node items?
Thanks in advance!
If you want to strech a TreeViewItem, you will have to copy its default ControlTemplate into your XAML and edit it as per your requirements.
It's a bunch of XAML but I am afraid there is no property or anything that you can set to accomplish this without defining a custom template:
<TreeView>
<TreeView.Resources>
<Style x:Key="TreeViewItemFocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Checked.Fill" Color="#FF595959"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Checked.Stroke" Color="#FF262626"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Stroke" Color="#FF27C7F7"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Fill" Color="#FFCCEEFB"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Checked.Stroke" Color="#FF1CC4F7"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.MouseOver.Checked.Fill" Color="#FF82DFFB"/>
<PathGeometry x:Key="TreeArrow" Figures="M0,0 L0,6 L6,0 z"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Fill" Color="#FFFFFFFF"/>
<SolidColorBrush x:Key="TreeViewItem.TreeArrow.Static.Stroke" Color="#FF818181"/>
<Style x:Key="ExpandCollapseToggleStyle" TargetType="{x:Type ToggleButton}">
<Setter Property="Focusable" Value="False"/>
<Setter Property="Width" Value="16"/>
<Setter Property="Height" Value="16"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Background="Transparent" Height="16" Padding="5,5,5,5" Width="16">
<Path x:Name="ExpandPath" Data="{StaticResource TreeArrow}" Fill="{StaticResource TreeViewItem.TreeArrow.Static.Fill}" Stroke="{StaticResource TreeViewItem.TreeArrow.Static.Stroke}">
<Path.RenderTransform>
<RotateTransform Angle="135" CenterY="3" CenterX="3"/>
</Path.RenderTransform>
</Path>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="RenderTransform" TargetName="ExpandPath">
<Setter.Value>
<RotateTransform Angle="180" CenterY="3" CenterX="3"/>
</Setter.Value>
</Setter>
<Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.Static.Checked.Fill}"/>
<Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.Static.Checked.Stroke}"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Stroke}"/>
<Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Fill}"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsMouseOver" Value="True"/>
<Condition Property="IsChecked" Value="True"/>
</MultiTrigger.Conditions>
<Setter Property="Stroke" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Checked.Stroke}"/>
<Setter Property="Fill" TargetName="ExpandPath" Value="{StaticResource TreeViewItem.TreeArrow.MouseOver.Checked.Fill}"/>
</MultiTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="StretchingTreeViewItemStyle" TargetType="{x:Type TreeViewItem}">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="HorizontalContentAlignment" Value="{Binding HorizontalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
<Setter Property="VerticalContentAlignment" Value="{Binding VerticalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
<Setter Property="Padding" Value="1,0,0,0"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
<Setter Property="FocusVisualStyle" Value="{StaticResource TreeViewItemFocusVisual}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition MinWidth="19" Width="Auto"/>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
</Grid.RowDefinitions>
<ToggleButton x:Name="Expander" ClickMode="Press" IsChecked="{Binding IsExpanded, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ExpandCollapseToggleStyle}"/>
<Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.Column="1" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="true"
Grid.ColumnSpan="2">
<ContentPresenter x:Name="PART_Header" ContentSource="Header" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Border>
<ItemsPresenter x:Name="ItemsHost" Grid.ColumnSpan="2" Grid.Column="1" Grid.Row="1"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="false">
<Setter Property="Visibility" TargetName="ItemsHost" Value="Collapsed"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Visibility" TargetName="Expander" Value="Hidden"/>
</Trigger>
<Trigger Property="IsSelected" Value="true">
<Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected" Value="true"/>
<Condition Property="IsSelectionActive" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.InactiveSelectionHighlightBrushKey}}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.InactiveSelectionHighlightTextBrushKey}}"/>
</MultiTrigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="VirtualizingPanel.IsVirtualizing" Value="true">
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<VirtualizingStackPanel/>
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
</TreeView.Resources>
<TreeViewItem Header="Node 1" Style="{StaticResource StretchingTreeViewItemStyle}">
<TreeViewItem Header="Leaf 1" />
<TreeViewItem Header="Leaf 2" />
</TreeViewItem>
<TreeViewItem Header="Node 2" Style="{StaticResource StretchingTreeViewItemStyle}" />
</TreeView>
I have a listview bound to a vm collection. The listview contains buttons, and what I'm trying to achieve is that when the user presses a button, it simply changes color. However, I can't figure out how to do this. Any help would be greatly appreciated.
<ListView
x:Name="GridControlOrders"
SelectionMode="Single"
ItemsSource="{Binding Orders}"
SelectedItem="{Binding Sale}"
ScrollViewer.HorizontalScrollBarVisibility="Disabled"
ScrollViewer.VerticalScrollBarVisibility="Auto">
<ListView.ItemsPanel>
<ItemsPanelTemplate>
<WrapPanel Orientation="Horizontal" />
</ItemsPanelTemplate>
</ListView.ItemsPanel>
<ListView.ItemTemplate>
<DataTemplate>
<Button Style="{StaticResource StyleButtonOrders}">
<Grid>
<TextBlock Text="{Binding DisplayData}"
HorizontalAlignment="Center"
VerticalAlignment="Center"
TextAlignment="Center"
TextWrapping="Wrap" />
</Grid>
</Button>
</DataTemplate>
</ListView.ItemTemplate>
<ListView.ItemContainerStyle>
<Style TargetType="{x:Type ListViewItem}">
<EventSetter Event="PreviewMouseDown" Handler="ItemOnPreviewMouseDown" />
<EventSetter Event="PreviewMouseUp" Handler="ItemOnPreviewMouseUp" />
<Setter Property="Width" Value="{Binding Source={x:Static p:Settings.Default}, Path=CardViewCardWidthItem, Mode=TwoWay}" />
<Setter Property="Height" Value="{Binding Source={x:Static p:Settings.Default}, Path=CardViewCardHeightItem, Mode=TwoWay}" />
</Style>
</ListView.ItemContainerStyle>
<ListView.Resources>
<Style TargetType="{x:Type ScrollBar}" BasedOn="{StaticResource StyleScrollBarTouchscreenNarrow}"/>
</ListView.Resources>
</ListView>
<Style TargetType="{x:Type Button}" x:Key="StyleButtonTouchscreen" BasedOn="{StaticResource {x:Type Button}}">
<Setter Property="Width" Value="Auto"/>
<Setter Property="Height" Value="Auto"/>
<Setter Property="Margin" Value="0"/>
<Setter Property="Template" Value="{StaticResource ButtonTouchControlTemplate}"/>
</Style>
<ControlTemplate x:Key="ButtonTouchControlTemplate" TargetType="{x:Type ButtonBase}">
<Border x:Name="border"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Background="{TemplateBinding Background}"
SnapsToDevicePixels="True">
<ContentPresenter x:Name="contentPresenter"
ContentTemplate="{TemplateBinding ContentTemplate}"
Content="{TemplateBinding Content}"
ContentStringFormat="{TemplateBinding ContentStringFormat}"
Focusable="False"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
Margin="{TemplateBinding Padding}"
RecognizesAccessKey="True"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"
VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="ToggleButton.IsChecked" Value="True">
<Setter Property="Background" TargetName="border" Value="Red"/>
<Setter Property="BorderBrush" TargetName="border" Value="Red"/>
</Trigger>
<Trigger Property="Button.IsDefaulted" Value="True">
<Setter Property="BorderBrush" TargetName="border" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Background" TargetName="border" Value="Orange"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Background" TargetName="border" Value="#FFF4F4F4"/>
<Setter Property="BorderBrush" TargetName="border" Value="#FFADB2B5"/>
<Setter Property="TextElement.Foreground" TargetName="contentPresenter" Value="#FF838383"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
Did you just want to create a listview with buttons that change color when the item (or button) is clicked? You can take advantage of the IsSelected property of the ListViewItem
<ListView.ItemContainerStyle>
<Style TargetType="ListViewItem">
<Setter Property="DataContext" Value="{Binding}" />
<Setter Property="Height" Value="30" />
<Setter Property="HorizontalAlignment" Value="Stretch" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ListViewItem">
<Border Background="Transparent" >
<Button x:Name="button" HorizontalAlignment="Left" Width="150" Content="{Binding DisplayData}" IsHitTestVisible="False"/>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter TargetName="button" Property="Background" Value="Red"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ListView.ItemContainerStyle>
Also, set SelectionMode="Single" on the ListView if you want only one button at a time to change background or SelectionMode="Multiple" if you want buttons at a time to change background when clicked.
I want to change the foregournd color for the selected value to White in my Combobox. Is there any way to perform the desire action.
Cheers
Whynottshirt
Style of my ComboBox:
<ResourceDictionary x:Class="Kororder.ApplicationDesign.Styles.MyCombo"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
<Color x:Key="GrayColor_">#FF928B81</Color>
<Color x:Key="LightGrayColor_">#FFC3C3C3</Color>
<Color x:Key="LightLightGrayColor_">#FFF1F1F1</Color>
<SolidColorBrush x:Key="GrayColor" Color="{StaticResource GrayColor_}"/>
<SolidColorBrush x:Key="LightGrayColor" Color="{StaticResource LightGrayColor_}"/>
<SolidColorBrush x:Key="LightLightGrayColor" Color="{StaticResource LightLightGrayColor_}"/>
<Color x:Key="BlueColor_">#0073b0</Color>
<Color x:Key="DarkBlueColor_">#FF004165</Color>
<Color x:Key="LightBlueColor_">#FFa4ddfa</Color>
<SolidColorBrush x:Key="BlueColor" Color="{StaticResource BlueColor_}" />
<SolidColorBrush x:Key="DarkBlueColor" Color="{StaticResource DarkBlueColor_}" />
<SolidColorBrush x:Key="LightBlueColor" Color="{StaticResource LightBlueColor_}" />
<SolidColorBrush x:Key="Foreground" Color="Black"/>
<SolidColorBrush x:Key="ForegroundWhite" Color="White"/>
<Style x:Key="LightGrayBox" TargetType="{x:Type Border}">
<Setter Property="Background" Value="White"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="SnapsToDevicePixels" Value="True"/>
<Setter Property="BorderBrush" Value="{StaticResource LightGrayColor}" />
</Style>
<Style x:Key="ComboBoxToggleButton" TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition Width="20"/>
</Grid.ColumnDefinitions>
<Border x:Name="Border" Style="{DynamicResource LightGrayBox}" Grid.ColumnSpan="2" />
<Path x:Name="Arrow" Grid.Column="1" Opacity="0.6" Fill="{StaticResource GrayColor}" HorizontalAlignment="Center" VerticalAlignment="Center" Data="M 0 0 L 4 4 L 8 0 Z"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="ToggleButton.IsMouseOver" Value="true">
<Setter TargetName="Arrow" Property="Opacity" Value="1" />
<Setter TargetName="Arrow" Property="Fill" Value="{StaticResource BlueColor}" />
<Setter TargetName="Border" Property="BorderBrush" Value="{DynamicResource BlueColor}"/>
</Trigger>
<Trigger Property="ToggleButton.IsChecked" Value="true">
<Setter TargetName="Arrow" Property="Opacity" Value="1" />
<Setter TargetName="Arrow" Property="Fill" Value="{StaticResource BlueColor}" />
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter TargetName="Border" Property="Style" Value="{StaticResource LightGrayBox}" />
<Setter Property="Foreground" Value="{StaticResource GrayColor}"/>
<Setter TargetName="Arrow" Property="Fill" Value="{StaticResource GrayColor}" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="ComboBoxToggleButtonActive" TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition/>
<ColumnDefinition Width="20"/>
</Grid.ColumnDefinitions>
<Border x:Name="Border" Grid.ColumnSpan="2" Background="{DynamicResource BlueColor}" />
<Path x:Name="Arrow" Grid.Column="1" Opacity="1" Fill="White" HorizontalAlignment="Center" VerticalAlignment="Center" Data="M 0 0 L 4 4 L 8 0 Z"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsFocused" Value="true">
<Setter TargetName="Border" Property="Background" Value="{DynamicResource BlueColor}" />
<Setter TargetName="Border" Property="BorderBrush" Value="White"/>
<Setter Property="Foreground" Value="White" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<ControlTemplate x:Key="ComboBoxTextBox" TargetType="TextBox">
<Border x:Name="PART_ContentHost" Focusable="False" Background="{TemplateBinding Background}" />
</ControlTemplate>
<Style x:Key="StandardComboBox" TargetType="{x:Type ComboBox}">
<Setter Property="Foreground" Value="{StaticResource Foreground}"/>
<Setter Property="Height" Value="25"/>
<Setter Property="HorizontalAlignment" Value="Left"/>
<Setter Property="IsEditable" Value="True" />
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="SnapsToDevicePixels" Value="true"/>
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.VerticalScrollBarVisibility" Value="Auto"/>
<Setter Property="ScrollViewer.CanContentScroll" Value="true"/>
<Setter Property="VerticalAlignment" Value="Top"/>
<Setter Property="Width" Value="120"/>
<Setter Property="IsSelected" Value="{Binding IsKeyboardFocusWithin, RelativeSource={RelativeSource Self}, Mode=OneWay}" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ComboBox">
<Grid GotFocus="OnGotFocus">
<ToggleButton Name="ToggleButton" Style="{StaticResource ComboBoxToggleButton}" Grid.Column="2" Focusable="false" ClickMode="Press"
IsChecked="{Binding Path=IsDropDownOpen, Mode=TwoWay, RelativeSource={RelativeSource TemplatedParent}}" />
<ContentPresenter Name="ContentSite" IsHitTestVisible="False" Content="{TemplateBinding SelectionBoxItem}" ContentTemplate="{TemplateBinding SelectionBoxItemTemplate}"
ContentTemplateSelector="{TemplateBinding ItemTemplateSelector}" Margin="3,3,23,3" VerticalAlignment="Center" HorizontalAlignment="Left" />
<TextBox x:Name="PART_EditableTextBox"
CaretBrush="{DynamicResource ForegroundWhite}"
Style="{x:Null}"
Template="{StaticResource ComboBoxTextBox}"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Margin="3,3,23,3"
Focusable="True"
Background="Transparent"
Foreground="{StaticResource Foreground}"
Visibility="Hidden"
IsReadOnly="{TemplateBinding IsReadOnly}"/>
<Popup VerticalOffset="-1" SnapsToDevicePixels="True" Name="Popup" Placement="Bottom" IsOpen="{TemplateBinding IsDropDownOpen}" AllowsTransparency="True" Focusable="False" PopupAnimation="Fade">
<Grid Name="DropDown" SnapsToDevicePixels="True" MinWidth="{TemplateBinding ActualWidth}" MaxHeight="200">
<Border x:Name="DropDownBorder" Style="{DynamicResource LightGrayBox}"/>
<ScrollViewer SnapsToDevicePixels="True">
<StackPanel IsItemsHost="True" KeyboardNavigation.DirectionalNavigation="Contained" />
</ScrollViewer>
</Grid>
</Popup>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="HasItems" Value="false">
<Setter TargetName="DropDownBorder" Property="MinHeight" Value="20"/>
</Trigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="{StaticResource GrayColor}"/>
</Trigger>
<Trigger Property="IsGrouping" Value="true">
<Setter Property="ScrollViewer.CanContentScroll" Value="false"/>
</Trigger>
<Trigger Property="IsSelected" Value="True">
<Setter TargetName="ToggleButton" Property="Style" Value="{StaticResource ComboBoxToggleButtonActive}" />
</Trigger>
<Trigger Property="IsEditable" Value="true">
<Setter Property="IsTabStop" Value="false"/>
<Setter TargetName="PART_EditableTextBox" Property="Visibility" Value="Visible"/>
<Setter TargetName="ContentSite" Property="Visibility" Value="Hidden"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Resources>
<Style TargetType="ComboBoxItem">
<Setter Property="SnapsToDevicePixels" Value="true"/>
<Setter Property="OverridesDefaultStyle" Value="true"/>
<Setter Property="HorizontalContentAlignment" Value="Left" />
<Setter Property="VerticalContentAlignment" Value="Center" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ComboBoxItem">
<Border Name="Border" Padding="2" SnapsToDevicePixels="true" BorderThickness="1">
<ContentPresenter />
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsHighlighted" Value="true">
<Setter TargetName="Border" Property="Background" Value="{DynamicResource BlueColor}"/>
<Setter TargetName="Border" Property="Padding" Value="2,3,2,3" />
<Setter Property="Foreground" Value="White" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Style.Resources>
</Style>
You should go to the msdn site and get the default control template for the combobox. After that you use it in your project and change it depending on your needs. Here: ComboBox ControlTemplate Example
Either that or use Expression Blend
How can I change the Background of a selected TreeViewItem when the TreeView (or the Application) looses Focus. A selected item by default has in this situation a light grey background.
EDIT: A try after first answer: But element with TargetName="Bd" will not be found.
<TreeView>
<TreeView.Resources>
<Style x:Key="{x:Type TreeViewItem}" TargetType="{x:Type TreeViewItem}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<ControlTemplate.Triggers>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected" Value="True"/>
<Condition Property="IsSelectionActive" Value="False"/>
</MultiTrigger.Conditions>
<Setter TargetName="Bd" Property="Background" Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" />
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}" />
</MultiTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</TreeView.Resources>
<TreeViewItem Header="Test1" IsExpanded="True">
<TreeViewItem Header="Test2" />
<TreeViewItem Header="Test3" />
<TreeViewItem Header="Test4" />
<TreeViewItem Header="Test5" />
</TreeViewItem>
</TreeView>
You need to modify the default style for TreeViewItem. Particularly, you need to modify the following trigger:
<Style x:Key="{x:Type TreeViewItem}"
TargetType="{x:Type TreeViewItem}">
...
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
...
<ControlTemplate.Triggers>
...
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected"
Value="true"/>
<Condition Property="IsSelectionActive"
Value="false"/>
</MultiTrigger.Conditions>
<Setter TargetName="Bd"
Property="Background"
Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
<Setter Property="Foreground"
Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
</MultiTrigger>
...
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
...
</Style>
As you can see the trigger sets the background to {DynamicResource {x:Static SystemColors.ControlBrushKey}} if the item is focused and the selection is not active (focus is somewhere else).
Update:
The full style of TreeViewItem for Aero theme looks like this:
<Style x:Key="{x:Type TreeViewItem}"
TargetType="{x:Type TreeViewItem}">
<Setter Property="Background"
Value="Transparent"/>
<Setter Property="HorizontalContentAlignment"
Value="{Binding Path=HorizontalContentAlignment,RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
<Setter Property="VerticalContentAlignment"
Value="{Binding Path=VerticalContentAlignment,RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
<Setter Property="Padding"
Value="1,0,0,0"/>
<Setter Property="Foreground"
Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
<Setter Property="FocusVisualStyle"
Value="{StaticResource TreeViewItemFocusVisual}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition MinWidth="19"
Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
</Grid.RowDefinitions>
<ToggleButton x:Name="Expander"
Style="{StaticResource ExpandCollapseToggleStyle}"
IsChecked="{Binding Path=IsExpanded,RelativeSource={RelativeSource TemplatedParent}}"
ClickMode="Press"/>
<Border Name="Bd"
Grid.Column="1"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Padding="{TemplateBinding Padding}"
SnapsToDevicePixels="true">
<ContentPresenter x:Name="PART_Header"
ContentSource="Header"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Border>
<ItemsPresenter x:Name="ItemsHost"
Grid.Row="1"
Grid.Column="1"
Grid.ColumnSpan="2"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded"
Value="false">
<Setter TargetName="ItemsHost"
Property="Visibility"
Value="Collapsed"/>
</Trigger>
<Trigger Property="HasItems"
Value="false">
<Setter TargetName="Expander"
Property="Visibility"
Value="Hidden"/>
</Trigger>
<Trigger Property="IsSelected"
Value="true">
<Setter TargetName="Bd"
Property="Background"
Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"/>
<Setter Property="Foreground"
Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected"
Value="true"/>
<Condition Property="IsSelectionActive"
Value="false"/>
</MultiTrigger.Conditions>
<Setter TargetName="Bd"
Property="Background"
Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
<Setter Property="Foreground"
Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
</MultiTrigger>
<Trigger Property="IsEnabled"
Value="false">
<Setter Property="Foreground"
Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="VirtualizingStackPanel.IsVirtualizing"
Value="true">
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<VirtualizingStackPanel/>
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
For that you'll also need this:
<PathGeometry x:Key="TreeArrow">
<PathGeometry.Figures>
<PathFigureCollection>
<PathFigure IsFilled="True"
StartPoint="0 0"
IsClosed="True">
<PathFigure.Segments>
<PathSegmentCollection>
<LineSegment Point="0 6"/>
<LineSegment Point="6 0"/>
</PathSegmentCollection>
</PathFigure.Segments>
</PathFigure>
</PathFigureCollection>
</PathGeometry.Figures>
</PathGeometry>
<Style x:Key="ExpandCollapseToggleStyle"
TargetType="{x:Type ToggleButton}">
<Setter Property="Focusable"
Value="False"/>
<Setter Property="Width"
Value="16"/>
<Setter Property="Height"
Value="16"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Width="16"
Height="16"
Background="Transparent"
Padding="5,5,5,5">
<Path x:Name="ExpandPath"
Fill="Transparent"
Stroke="#FF989898"
Data="{StaticResource TreeArrow}">
<Path.RenderTransform>
<RotateTransform Angle="135"
CenterX="3"
CenterY="3"/>
</Path.RenderTransform>
</Path>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver"
Value="True">
<Setter TargetName="ExpandPath"
Property="Stroke"
Value="#FF1BBBFA"/>
<Setter TargetName="ExpandPath"
Property="Fill"
Value="Transparent"/>
</Trigger>
<Trigger Property="IsChecked"
Value="True">
<Setter TargetName="ExpandPath"
Property="RenderTransform">
<Setter.Value>
<RotateTransform Angle="180"
CenterX="3"
CenterY="3"/>
</Setter.Value>
</Setter>
<Setter TargetName="ExpandPath"
Property="Fill"
Value="#FF595959"/>
<Setter TargetName="ExpandPath"
Property="Stroke"
Value="#FF262626"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
In all of this you need to modify only the part you are interested in (the background color if selection is inactive) and place those styles in the resources section in App.xaml in your main window.
More easy way for your particular case exists. Like in ListBox, you can replace ControlBrush resource for TreeViewItem's using style:
<Style TargetType="TreeViewItem">
<Style.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.ControlBrushKey}" Color="{x:Static SystemColors.HighlightColor}" Opacity=".4" />
</Style.Resources>
</Style>
You can specify any other color. Opacity is suggested because if your have several TreeView/ListBox you can determine which one is focused. But of course, editing full style can bring you much more flexibility for future customizations.
Sample with gradients:
<Style TargetType="TreeViewItem">
<Style.Resources>
<LinearGradientBrush x:Key="{x:Static SystemColors.ControlBrushKey}" EndPoint='0 1'>
<GradientStop Color='#AA00FF00' />
<GradientStop Offset='1' Color='#AA007700' />
</LinearGradientBrush>
<LinearGradientBrush x:Key="{x:Static SystemColors.HighlightBrushKey}" EndPoint='0 1'>
<GradientStop Color='#AA00FF00' />
<GradientStop Offset='1' Color='#AA007700' />
</LinearGradientBrush>
</Style.Resources>
</Style>
If you don't want to override the default contol template, you can define your own template for the headers using textblock and apply the style in that template to the textblock itself (there's a small padding in the default control template of TreeViewItem, so you should also set it to zero to achieve pixel-perfection).
<TreeView.Resources>
<Style TargetType="TreeViewItem">
<Setter Property="Padding" Value="0"/>
<Setter Property="HeaderTemplate">
<Setter.Value>
<DataTemplate>
<DataTemplate.Resources>
<Style TargetType="TextBlock">
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding IsSelected, RelativeSource={RelativeSource AncestorType=TreeViewItem}}" Value="True"/>
<Condition Binding="{Binding IsSelectionActive, RelativeSource={RelativeSource AncestorType=TreeViewItem}}" Value="False"/>
</MultiDataTrigger.Conditions>
<Setter Property="Background" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}" />
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}" />
</MultiDataTrigger>
</Style.Triggers>
</Style>
</DataTemplate.Resources>
<TextBlock Text="{Binding}"></TextBlock>
</DataTemplate>
</Setter.Value>
</Setter>
</Style>
</TreeView.Resources>
<TreeViewItem Header="Test1" IsExpanded="True">
<TreeViewItem Header="Test2" />
<TreeViewItem Header="Test3" />
<TreeViewItem Header="Test4" />
<TreeViewItem Header="Test5" />
</TreeViewItem>
How to hide the expand/collpse sign for leaf nodes in a WPF TreeView?
In other words: how to make leaf nodes automatically expand?
Any way to achive this using XAML?
Thanks,
Similar to other answers, to Expand all nodes you can just use
<TreeView >
<TreeView.ItemContainerStyle>
<Style TargetType="{x:Type TreeViewItem}">
<Setter Property="IsExpanded" Value="True" />
</Style>
</TreeView.ItemContainerStyle>
This will make all TreeViewItems automatically Expand. However, you'll still see the Expand/Collapse ToggleButton. To get rid of that one you'll have to re-template TreeViewItem like this
<TreeView ...
ItemContainerStyle="{StaticResource TreeViewItemExpandedStyle}">
And the Style (pretty much Xaml)
<Style x:Key="TreeViewItemExpandedStyle" TargetType="{x:Type TreeViewItem}">
<Setter Property="Background" Value="Transparent"/>
<Setter Property="IsExpanded" Value="True"/>
<Setter Property="HorizontalContentAlignment" Value="{Binding HorizontalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
<Setter Property="VerticalContentAlignment" Value="{Binding VerticalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
<Setter Property="Padding" Value="1,0,0,0"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
<Setter Property="FocusVisualStyle" Value="{StaticResource TreeViewItemFocusVisual}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition MinWidth="19" Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition/>
</Grid.RowDefinitions>
<ToggleButton x:Name="Expander" IsEnabled="False" Visibility="Hidden" ClickMode="Press" IsChecked="{Binding IsExpanded, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ExpandCollapseToggleStyle}"/>
<Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.Column="1" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="true">
<ContentPresenter x:Name="PART_Header" ContentSource="Header" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Border>
<ItemsPresenter x:Name="ItemsHost" Grid.ColumnSpan="2" Grid.Column="1" Grid.Row="1"/>
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="false">
<Setter Property="Visibility" TargetName="ItemsHost" Value="Collapsed"/>
</Trigger>
<Trigger Property="HasItems" Value="false">
<Setter Property="Visibility" TargetName="Expander" Value="Hidden"/>
</Trigger>
<Trigger Property="IsSelected" Value="true">
<Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}"/>
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="IsSelected" Value="true"/>
<Condition Property="IsSelectionActive" Value="false"/>
</MultiTrigger.Conditions>
<Setter Property="Background" TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.ControlBrushKey}}"/>
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.ControlTextBrushKey}}"/>
</MultiTrigger>
<Trigger Property="IsEnabled" Value="false">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="VirtualizingStackPanel.IsVirtualizing" Value="true">
<Setter Property="ItemsPanel">
<Setter.Value>
<ItemsPanelTemplate>
<VirtualizingStackPanel/>
</ItemsPanelTemplate>
</Setter.Value>
</Setter>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="TreeViewItemFocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Rectangle/>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<PathGeometry x:Key="TreeArrow" Figures="M0,0 L0,6 L6,0 z"/>
<Style x:Key="ExpandCollapseToggleStyle" TargetType="{x:Type ToggleButton}">
<Setter Property="Focusable" Value="False"/>
<Setter Property="Width" Value="16"/>
<Setter Property="Height" Value="16"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Background="Transparent" Height="16" Padding="5,5,5,5" Width="16">
<Path x:Name="ExpandPath" Data="{StaticResource TreeArrow}" Fill="Transparent" Stroke="#FF989898">
<Path.RenderTransform>
<RotateTransform Angle="135" CenterY="3" CenterX="3"/>
</Path.RenderTransform>
</Path>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="ExpandPath" Value="#FF1BBBFA"/>
<Setter Property="Fill" TargetName="ExpandPath" Value="Transparent"/>
</Trigger>
<Trigger Property="IsChecked" Value="True">
<Setter Property="RenderTransform" TargetName="ExpandPath">
<Setter.Value>
<RotateTransform Angle="180" CenterY="3" CenterX="3"/>
</Setter.Value>
</Setter>
<Setter Property="Fill" TargetName="ExpandPath" Value="#FF595959"/>
<Setter Property="Stroke" TargetName="ExpandPath" Value="#FF262626"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Bind the TreeViewItems to an ObservableCollection and leave the ObservableCollection empty. That way the expand/collapse sign is not shown since the UI knows there is nothing to expand. Here is the relevant part from some of my code:
XAML:
<TreeView x:Name="TreeView"
ItemsSource="{Binding TopLevelNodes}"
VirtualizingStackPanel.IsVirtualizing="True"
VirtualizingStackPanel.VirtualizationMode="Recycling">
<TreeView.Resources>
<HierarchicalDataTemplate
DataType="{x:Type local:ViewModel}" ItemsSource="{Binding Children}">
ViewModel:
ObservableCollection<ObjectBaseViewModel> _children;
public ObservableCollection<ObjectBaseViewModel> Children
{
get
{
if (_children == null)
_children = new ObservableCollection<ViewModel>();
return _children;
}
}
I don't know about a pure XAML solution but you could bind the IsExpanded property of the TreeviewItem and have this property on your leaf nodes set to true by default (you don't have to have this property at all on other nodes.
<Style TargetType="controls:TreeViewItem">
<Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay}"></Setter>
</Style>
Firstly set IsExpanded to true
<Style x:Key="{x:Type TreeViewItem}"
TargetType="{x:Type TreeViewItem}">
<Setter Property="IsExpanded"
Value="True" />
Then hide the Expander
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<ControlTemplate.Triggers>
<Trigger Property="HasItems"
Value="false">
<Setter TargetName="Expander"
Property="Visibility"
Value="Hidden" />
</Trigger>
<Trigger Property="HasItems"
Value="true">
<Setter TargetName="Expander"
Property="Visibility"
Value="Hidden" />
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
A very good reason to use a treeview rather than a datagrid with rowdetails is that the up and down arrow keys traverse from expanded details to header details seamlessly.