TreeView Styles and Templates
This topic describes the styles and templates for the TreeView control. You can modify the default ControlTemplate to give the control a unique appearance. For more information, see Create a template for a control.
TreeView Parts
The TreeView control does not have any named parts.
When you create a ControlTemplate for an TreeView, your template might contain a ItemsPresenter within a ScrollViewer. (The ItemsPresenter displays each item in the TreeView; the ScrollViewer enables scrolling within the control). If the ItemsPresenter is not the direct child of the ScrollViewer, you must give the ItemsPresenter the name, ItemsPresenter
.
TreeView States
The following table lists the visual states for the TreeView control.
VisualState Name | VisualStateGroup Name | Description |
---|---|---|
Valid | ValidationStates | The control uses the Validation class and the Validation.HasError attached property is false . |
InvalidFocused | ValidationStates | The Validation.HasError attached property is true has the control has focus. |
InvalidUnfocused | ValidationStates | The Validation.HasError attached property is true has the control does not have focus. |
TreeViewItem Parts
The following table lists the named parts for the TreeViewItem control.
Part | Type | Description |
---|---|---|
PART_Header | FrameworkElement | A visual element that contains that header content of the TreeView control. |
TreeViewItem States
The following table lists the visual states for TreeViewItem control.
VisualState Name | VisualStateGroup Name | Description |
---|---|---|
Normal | CommonStates | The default state. |
MouseOver | CommonStates | The mouse pointer is positioned over the TreeViewItem. |
Disabled | CommonStates | The TreeViewItem is disabled. |
Focused | FocusStates | The TreeViewItem has focus. |
Unfocused | FocusStates | The TreeViewItem does not have focus. |
Expanded | ExpansionStates | The TreeViewItem control is expanded. |
Collapsed | ExpansionStates | The TreeViewItem control is collapsed. |
HasItems | HasItemsStates | The TreeViewItem has items. |
NoItems | HasItemsStates | The TreeViewItem does not have items. |
Selected | SelectionStates | The TreeViewItem is selected. |
SelectedInactive | SelectionStates | The TreeViewItem is selected but not active. |
Unselected | SelectionStates | The TreeViewItem is not selected. |
Valid | ValidationStates | The control uses the Validation class and the Validation.HasError attached property is false . |
InvalidFocused | ValidationStates | The Validation.HasError attached property is true has the control has focus. |
InvalidUnfocused | ValidationStates | The Validation.HasError attached property is true has the control does not have focus. |
TreeView ControlTemplate Example
The following example shows how to define a ControlTemplate for the TreeView control and its associated types.
<Style x:Key="{x:Type TreeView}"
TargetType="TreeView">
<Setter Property="OverridesDefaultStyle"
Value="True" />
<Setter Property="SnapsToDevicePixels"
Value="True" />
<Setter Property="ScrollViewer.HorizontalScrollBarVisibility"
Value="Auto" />
<Setter Property="ScrollViewer.VerticalScrollBarVisibility"
Value="Auto" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="TreeView">
<Border Name="Border"
CornerRadius="1"
BorderThickness="1">
<Border.BorderBrush>
<SolidColorBrush Color="{DynamicResource BorderMediumColor}" />
</Border.BorderBrush>
<Border.Background>
<SolidColorBrush Color="{DynamicResource ControlLightColor}" />
</Border.Background>
<ScrollViewer Focusable="False"
CanContentScroll="False"
Padding="4">
<ItemsPresenter />
</ScrollViewer>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="ExpandCollapseToggleStyle"
TargetType="ToggleButton">
<Setter Property="Focusable"
Value="False" />
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="ToggleButton">
<Grid Width="15"
Height="13"
Background="Transparent">
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CheckStates">
<VisualState x:Name="Checked">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)"
Storyboard.TargetName="Collapsed">
<DiscreteObjectKeyFrame KeyTime="0"
Value="{x:Static Visibility.Hidden}" />
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)"
Storyboard.TargetName="Expanded">
<DiscreteObjectKeyFrame KeyTime="0"
Value="{x:Static Visibility.Visible}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unchecked" />
<VisualState x:Name="Indeterminate" />
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Path x:Name="Collapsed"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Margin="1,1,1,1"
Data="M 4 0 L 8 4 L 4 8 Z">
<Path.Fill>
<SolidColorBrush Color="{DynamicResource GlyphColor}" />
</Path.Fill>
</Path>
<Path x:Name="Expanded"
HorizontalAlignment="Left"
VerticalAlignment="Center"
Margin="1,1,1,1"
Data="M 0 4 L 8 4 L 4 8 Z"
Visibility="Hidden">
<Path.Fill>
<SolidColorBrush Color="{DynamicResource GlyphColor}" />
</Path.Fill>
</Path>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style x:Key="TreeViewItemFocusVisual">
<Setter Property="Control.Template">
<Setter.Value>
<ControlTemplate>
<Border>
<Rectangle Margin="0,0,0,0"
StrokeThickness="5"
Stroke="Black"
StrokeDashArray="1 2"
Opacity="0" />
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<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>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="SelectionStates">
<VisualState x:Name="Selected">
<Storyboard>
<ColorAnimationUsingKeyFrames Storyboard.TargetName="Bd"
Storyboard.TargetProperty="(Panel.Background).
(SolidColorBrush.Color)"
>
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource SelectedBackgroundColor}" />
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Unselected" />
<VisualState x:Name="SelectedInactive">
<Storyboard>
<ColorAnimationUsingKeyFrames Storyboard.TargetName="Bd"
Storyboard.TargetProperty="(Panel.Background).
(SolidColorBrush.Color)">
<EasingColorKeyFrame KeyTime="0"
Value="{StaticResource SelectedUnfocusedColor}" />
</ColorAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
<VisualStateGroup x:Name="ExpansionStates">
<VisualState x:Name="Expanded">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="(UIElement.Visibility)"
Storyboard.TargetName="ItemsHost">
<DiscreteObjectKeyFrame KeyTime="0"
Value="{x:Static Visibility.Visible}" />
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="Collapsed" />
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<ToggleButton x:Name="Expander"
Style="{StaticResource ExpandCollapseToggleStyle}"
ClickMode="Press"
IsChecked="{Binding IsExpanded,
RelativeSource={RelativeSource TemplatedParent}}"/>
<Border x:Name="Bd"
Grid.Column="1"
Background="{TemplateBinding Background}"
BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}"
Padding="{TemplateBinding Padding}">
<ContentPresenter x:Name="PART_Header"
ContentSource="Header"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"/>
</Border>
<ItemsPresenter x:Name="ItemsHost"
Grid.Row="1"
Grid.Column="1"
Grid.ColumnSpan="2"
Visibility="Collapsed" />
</Grid>
<ControlTemplate.Triggers>
<Trigger Property="HasItems"
Value="false">
<Setter TargetName="Expander"
Property="Visibility"
Value="Hidden" />
</Trigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="HasHeader"
Value="false" />
<Condition Property="Width"
Value="Auto" />
</MultiTrigger.Conditions>
<Setter TargetName="PART_Header"
Property="MinWidth"
Value="75" />
</MultiTrigger>
<MultiTrigger>
<MultiTrigger.Conditions>
<Condition Property="HasHeader"
Value="false" />
<Condition Property="Height"
Value="Auto" />
</MultiTrigger.Conditions>
<Setter TargetName="PART_Header"
Property="MinHeight"
Value="19" />
</MultiTrigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
The preceding example uses one or more of the following resources.
<!--Control colors.-->
<Color x:Key="WindowColor">#FFE8EDF9</Color>
<Color x:Key="ContentAreaColorLight">#FFC5CBF9</Color>
<Color x:Key="ContentAreaColorDark">#FF7381F9</Color>
<Color x:Key="DisabledControlLightColor">#FFE8EDF9</Color>
<Color x:Key="DisabledControlDarkColor">#FFC5CBF9</Color>
<Color x:Key="DisabledForegroundColor">#FF888888</Color>
<Color x:Key="SelectedBackgroundColor">#FFC5CBF9</Color>
<Color x:Key="SelectedUnfocusedColor">#FFDDDDDD</Color>
<Color x:Key="ControlLightColor">White</Color>
<Color x:Key="ControlMediumColor">#FF7381F9</Color>
<Color x:Key="ControlDarkColor">#FF211AA9</Color>
<Color x:Key="ControlMouseOverColor">#FF3843C4</Color>
<Color x:Key="ControlPressedColor">#FF211AA9</Color>
<Color x:Key="GlyphColor">#FF444444</Color>
<Color x:Key="GlyphMouseOver">sc#1, 0.004391443, 0.002428215, 0.242281124</Color>
<!--Border colors-->
<Color x:Key="BorderLightColor">#FFCCCCCC</Color>
<Color x:Key="BorderMediumColor">#FF888888</Color>
<Color x:Key="BorderDarkColor">#FF444444</Color>
<Color x:Key="PressedBorderLightColor">#FF888888</Color>
<Color x:Key="PressedBorderDarkColor">#FF444444</Color>
<Color x:Key="DisabledBorderLightColor">#FFAAAAAA</Color>
<Color x:Key="DisabledBorderDarkColor">#FF888888</Color>
<Color x:Key="DefaultBorderBrushDarkColor">Black</Color>
<!--Control-specific resources.-->
<Color x:Key="HeaderTopColor">#FFC5CBF9</Color>
<Color x:Key="DatagridCurrentCellBorderColor">Black</Color>
<Color x:Key="SliderTrackDarkColor">#FFC5CBF9</Color>
<Color x:Key="NavButtonFrameColor">#FF3843C4</Color>
<LinearGradientBrush x:Key="MenuPopupBrush"
EndPoint="0.5,1"
StartPoint="0.5,0">
<GradientStop Color="{DynamicResource ControlLightColor}"
Offset="0" />
<GradientStop Color="{DynamicResource ControlMediumColor}"
Offset="0.5" />
<GradientStop Color="{DynamicResource ControlLightColor}"
Offset="1" />
</LinearGradientBrush>
<LinearGradientBrush x:Key="ProgressBarIndicatorAnimatedFill"
StartPoint="0,0"
EndPoint="1,0">
<LinearGradientBrush.GradientStops>
<GradientStopCollection>
<GradientStop Color="#000000FF"
Offset="0" />
<GradientStop Color="#600000FF"
Offset="0.4" />
<GradientStop Color="#600000FF"
Offset="0.6" />
<GradientStop Color="#000000FF"
Offset="1" />
</GradientStopCollection>
</LinearGradientBrush.GradientStops>
</LinearGradientBrush>
For the complete sample, see Styling with ControlTemplates Sample.
See also
.NET Desktop feedback