如果 WPF 中没有子项，则隐藏扩展器切换按钮 [英] Hide Expander ToggleButton if no child items in WPF
本文介绍了如果 WPF 中没有子项，则隐藏扩展器切换按钮的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我在列表框中使用扩展器控件来显示项目的分层列表，并且我正确地获得了可见性.这是我在 xaml 中用来绑定数据的代码
I am using an expander control inside the Listbox to show a Hierarchical list of items and i am getting the visibility correctly. Here is the code i used in xaml to bind the data
<Window.Resources>
<ControlTemplate x:Key="WithoutToggleButton" TargetType="{x:Type Expander}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="3" SnapsToDevicePixels="True">
<ToggleButton x:Name="HeaderSite" ContentTemplate="{TemplateBinding HeaderTemplate}" Content="{TemplateBinding Header}" DockPanel.Dock="Top" 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}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}">
<ToggleButton.Template>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Padding="{TemplateBinding Padding}">
<ContentPresenter ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Grid.Column="1" ContentStringFormat="{TemplateBinding ContentStringFormat}" HorizontalAlignment="Left" Margin="4,0,0,0" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Center"/>
</Border>
</ControlTemplate>
</ToggleButton.Template>
</ToggleButton>
</Border>
</ControlTemplate>
<ControlTemplate x:Key="WithToggleButton" TargetType="{x:Type Expander}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="3" SnapsToDevicePixels="True">
<DockPanel>
<ToggleButton x:Name="HeaderSite" ContentTemplate="{TemplateBinding HeaderTemplate}" Content="{TemplateBinding Header}" DockPanel.Dock="Top" 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}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}">
<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.Style>
<Style 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="19"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Ellipse x:Name="circle" Fill="White" HorizontalAlignment="Center" Height="19" Stroke="#FF333333" VerticalAlignment="Center" Width="19"/>
<Path x:Name="arrow" Data="M1,1.5L4.5,5 8,1.5" HorizontalAlignment="Center" SnapsToDevicePixels="False" Stroke="#FF333333" StrokeThickness="2" VerticalAlignment="Center"/>
<ContentPresenter ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Grid.Column="1" ContentStringFormat="{TemplateBinding ContentStringFormat}" HorizontalAlignment="Left" Margin="4,0,0,0" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Center"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Data" TargetName="arrow" Value="M1,4.5L4.5,1 8,4.5"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF5593FF"/>
<Setter Property="Fill" TargetName="circle" Value="#FFF3F9FF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF3C77DD"/>
<Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
<Setter Property="Fill" TargetName="circle" Value="#FFD9ECFF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Stroke" TargetName="circle" Value="#FFBCBCBC"/>
<Setter Property="Fill" TargetName="circle" Value="#FFE6E6E6"/>
<Setter Property="Stroke" TargetName="arrow" Value="#FF707070"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ToggleButton.Style>
</ToggleButton>
<ContentPresenter x:Name="ExpandSite" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" ContentStringFormat="{TemplateBinding ContentStringFormat}" DockPanel.Dock="Bottom" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" Visibility="Collapsed" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</DockPanel>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="True">
<Setter Property="Visibility" TargetName="ExpandSite" Value="Visible"/>
</Trigger>
<Trigger Property="ExpandDirection" Value="Right">
<Setter Property="DockPanel.Dock" TargetName="ExpandSite" Value="Right"/>
<Setter Property="DockPanel.Dock" TargetName="HeaderSite" Value="Left"/>
<Setter Property="Style" TargetName="HeaderSite">
<Setter.Value>
<Style TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Padding="{TemplateBinding Padding}">
<Grid Background="Transparent" SnapsToDevicePixels="False">
<Grid.RowDefinitions>
<RowDefinition Height="19"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid>
<Grid.LayoutTransform>
<TransformGroup>
<RotateTransform Angle="-90"/>
</TransformGroup>
</Grid.LayoutTransform>
<Ellipse x:Name="circle" Fill="White" HorizontalAlignment="Center" Height="19" Stroke="#FF333333" VerticalAlignment="Center" Width="19"/>
<Path x:Name="arrow" Data="M1,1.5L4.5,5 8,1.5" HorizontalAlignment="Center" SnapsToDevicePixels="False" Stroke="#FF333333" StrokeThickness="2" VerticalAlignment="Center"/>
</Grid>
<ContentPresenter ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" ContentStringFormat="{TemplateBinding ContentStringFormat}" HorizontalAlignment="Center" Margin="0,4,0,0" Grid.Row="1" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Top"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Data" TargetName="arrow" Value="M1,4.5L4.5,1 8,4.5"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF5593FF"/>
<Setter Property="Fill" TargetName="circle" Value="#FFF3F9FF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF3C77DD"/>
<Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
<Setter Property="Fill" TargetName="circle" Value="#FFD9ECFF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Stroke" TargetName="circle" Value="#FFBCBCBC"/>
<Setter Property="Fill" TargetName="circle" Value="#FFE6E6E6"/>
<Setter Property="Stroke" TargetName="arrow" Value="#FF707070"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="ExpandDirection" Value="Up">
<Setter Property="DockPanel.Dock" TargetName="ExpandSite" Value="Top"/>
<Setter Property="DockPanel.Dock" TargetName="HeaderSite" Value="Bottom"/>
<Setter Property="Style" TargetName="HeaderSite">
<Setter.Value>
<Style 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="19"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Grid>
<Grid.LayoutTransform>
<TransformGroup>
<RotateTransform Angle="180"/>
</TransformGroup>
</Grid.LayoutTransform>
<Ellipse x:Name="circle" Fill="White" HorizontalAlignment="Center" Height="19" Stroke="#FF333333" VerticalAlignment="Center" Width="19"/>
<Path x:Name="arrow" Data="M1,1.5L4.5,5 8,1.5" HorizontalAlignment="Center" SnapsToDevicePixels="False" Stroke="#FF333333" StrokeThickness="2" VerticalAlignment="Center"/>
</Grid>
<ContentPresenter ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Grid.Column="1" ContentStringFormat="{TemplateBinding ContentStringFormat}" HorizontalAlignment="Left" Margin="4,0,0,0" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Center"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Data" TargetName="arrow" Value="M1,4.5L4.5,1 8,4.5"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF5593FF"/>
<Setter Property="Fill" TargetName="circle" Value="#FFF3F9FF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF3C77DD"/>
<Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
<Setter Property="Fill" TargetName="circle" Value="#FFD9ECFF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Stroke" TargetName="circle" Value="#FFBCBCBC"/>
<Setter Property="Fill" TargetName="circle" Value="#FFE6E6E6"/>
<Setter Property="Stroke" TargetName="arrow" Value="#FF707070"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="ExpandDirection" Value="Left">
<Setter Property="DockPanel.Dock" TargetName="ExpandSite" Value="Left"/>
<Setter Property="DockPanel.Dock" TargetName="HeaderSite" Value="Right"/>
<Setter Property="Style" TargetName="HeaderSite">
<Setter.Value>
<Style TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Padding="{TemplateBinding Padding}">
<Grid Background="Transparent" SnapsToDevicePixels="False">
<Grid.RowDefinitions>
<RowDefinition Height="19"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid>
<Grid.LayoutTransform>
<TransformGroup>
<RotateTransform Angle="90"/>
</TransformGroup>
</Grid.LayoutTransform>
<Ellipse x:Name="circle" Fill="White" HorizontalAlignment="Center" Height="19" Stroke="#FF333333" VerticalAlignment="Center" Width="19"/>
<Path x:Name="arrow" Data="M1,1.5L4.5,5 8,1.5" HorizontalAlignment="Center" SnapsToDevicePixels="False" Stroke="#FF333333" StrokeThickness="2" VerticalAlignment="Center"/>
</Grid>
<ContentPresenter ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" ContentStringFormat="{TemplateBinding ContentStringFormat}" HorizontalAlignment="Center" Margin="0,4,0,0" Grid.Row="1" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Top"/>
</Grid>
</Border>
<ControlTemplate.Triggers>
<Trigger Property="IsChecked" Value="True">
<Setter Property="Data" TargetName="arrow" Value="M1,4.5L4.5,1 8,4.5"/>
</Trigger>
<Trigger Property="IsMouseOver" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF5593FF"/>
<Setter Property="Fill" TargetName="circle" Value="#FFF3F9FF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsPressed" Value="True">
<Setter Property="Stroke" TargetName="circle" Value="#FF3C77DD"/>
<Setter Property="StrokeThickness" TargetName="circle" Value="1.5"/>
<Setter Property="Fill" TargetName="circle" Value="#FFD9ECFF"/>
<Setter Property="Stroke" TargetName="arrow" Value="Black"/>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Stroke" TargetName="circle" Value="#FFBCBCBC"/>
<Setter Property="Fill" TargetName="circle" Value="#FFE6E6E6"/>
<Setter Property="Stroke" TargetName="arrow" Value="#FF707070"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</Setter.Value>
</Setter>
</Trigger>
<Trigger Property="IsEnabled" Value="False">
<Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Window.Resources>
<ItemsControl.ItemTemplate>
<DataTemplate>
<Expander ExpandDirection="Down"
IsExpanded="{Binding Mode=TwoWay, Path=IsSelected, RelativeSource={RelativeSource AncestorType=ListBoxItem, Mode=FindAncestor}}" >
<Expander.Header>
<BulletDecorator>
<Button Tag="{Binding}" Style="{StaticResource ResourceKey=BookPageStyle}" Click="MainChapterButton_Click" Content="{Binding Path=name}" >
</Button>
</BulletDecorator>
</Expander.Header>
<StackPanel>
<ListBox x:Name="SubChapListBox" BorderThickness="0" Margin="20,0" ItemsSource="{Binding Path=chapters}" >
<ListBox.ItemTemplate>
<DataTemplate>
<Expander ExpandDirection="Down" BorderThickness="0" >
<Expander.Header>
<BulletDecorator>
<Button Tag="{Binding}" Style="{StaticResource ResourceKey=BookPageStyle}" Click="SubchpaterButton_Click" Content="{Binding Path=name}" >
</Button>
</BulletDecorator>
</Expander.Header>
</Expander>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</Expander>
</DataTemplate>
</ItemsControl.ItemTemplate>
问题是我得到了 Expander Bullet ，即使 Expander 中没有子项.我怎样才能避免这种情况?
The problem is i am getting Expander Bullet , even if there is no child items in the Expander. How can i avoid that ?
这就是我想要做的.我可以通过 XAML 修改来实现吗??这是我尝试过的完整源代码的链接https://onedrive.live.com/redir?resid=529BE5C1D41B4A28%21347
Here is what i am trying to do . Can i did it via XAML modification?? Here is the link to complete source code i tried https://onedrive.live.com/redir?resid=529BE5C1D41B4A28%21347
推荐答案
我为扩展器WithToggleButton和WithoutToggleButton设计了两个模板.
I have designed Two template for expander WithToggleButton and WithoutToggleButton.
<Window.Resources>
<ControlTemplate x:Key="WithToggleButton" TargetType="{x:Type Expander}">
<!--Copy from msdn link as there is limitation to add code in stackoverflow-->
</ControlTemplate>
<ControlTemplate x:Key="WithoutToggleButton" TargetType="{x:Type Expander}">
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" CornerRadius="3" SnapsToDevicePixels="True">
<DockPanel>
<ToggleButton x:Name="HeaderSite" ContentTemplate="{TemplateBinding HeaderTemplate}" Content="{TemplateBinding Header}" DockPanel.Dock="Top" 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}" VerticalContentAlignment="{TemplateBinding VerticalContentAlignment}">
<ToggleButton.Style>
<Style TargetType="{x:Type ToggleButton}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type ToggleButton}">
<Border Padding="{TemplateBinding Padding}">
<ContentPresenter ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" Grid.Column="1" ContentStringFormat="{TemplateBinding ContentStringFormat}" HorizontalAlignment="Left" Margin="4,0,0,0" RecognizesAccessKey="True" SnapsToDevicePixels="True" VerticalAlignment="Center"/>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
</ToggleButton.Style>
</ToggleButton>
<ContentPresenter x:Name="ExpandSite" ContentTemplate="{TemplateBinding ContentTemplate}" Content="{TemplateBinding Content}" ContentStringFormat="{TemplateBinding ContentStringFormat}" DockPanel.Dock="Bottom" Focusable="False" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" Margin="{TemplateBinding Padding}" Visibility="Collapsed" VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>
</DockPanel>
</Border>
</ControlTemplate>
</Window.Resources>
<StackPanel>
<Expander Header="ExpanderWithoutContent" x:Name="Expander">
<Expander.Style>
<Style TargetType="Expander">
<Setter Property="Template" Value="{StaticResource WithToggleButton}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Content,ElementName=Expander}" Value="{x:Null}">
<Setter Property="Template" Value="{StaticResource WithoutToggleButton}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Expander.Style>
</Expander>
<Expander x:Name="Expander1" Header="ExpanderWithContent" >
<Expander.Style>
<Style TargetType="Expander">
<Setter Property="Template" Value="{StaticResource WithToggleButton}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Content,ElementName=Expander1}" Value="{x:Null}">
<Setter Property="Template" Value="{StaticResource WithoutToggleButton}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Expander.Style>
<Expander.Content>
<Grid Height="50" Background="Green">
<TextBlock Text="expander content" Foreground="White" FontSize="20" VerticalAlignment="Center"></TextBlock>
</Grid>
</Expander.Content>
</Expander>
</StackPanel>
结果
更新
请在您现有的窗口资源中添加上面的扩展器模板 WithToggleButton 和 WithoutToggleButton，并用下面的新 xaml 代码替换您的网格.
Plesae Add above expander template WithToggleButton and WithoutToggleButton in your existing window resource and replace your grid with below new xaml code.
<Grid >
<ScrollViewer ScrollViewer.VerticalScrollBarVisibility="Auto" Margin="10" Background="White">
<Grid>
<Label Name="lblstatus" HorizontalAlignment="center" VerticalAlignment="top" Margin="10" FontSize="14" FontWeight="bold" Foreground="Black" >Please wait...</Label>
<ListBox ItemsSource="{Binding}" Name="TOCView" ItemContainerStyle="{StaticResource ListBoxItemStyle}">
<ItemsControl.ItemTemplate>
<DataTemplate>
<Expander x:Name="Expander" ExpandDirection="Down" IsExpanded="{Binding Mode=TwoWay, Path=IsSelected, RelativeSource={RelativeSource AncestorType=ListBoxItem, Mode=FindAncestor}}" >
<Expander.Style>
<Style TargetType="Expander" BasedOn="{StaticResource ExpanderItemStyle}">
<Setter Property="Template" Value="{StaticResource WithToggleButton}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=chapters}" Value="{x:Null}">
<Setter Property="Template" Value="{StaticResource WithoutToggleButton}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Expander.Style>
<Expander.Header>
<BulletDecorator>
<Button Tag="{Binding}" Style="{StaticResource ResourceKey=BookPageStyle}" Click="MainChapterButton_Click" Content="{Binding Path=name}"/>
</BulletDecorator>
</Expander.Header>
<Expander.Content>
<StackPanel>
<ListBox x:Name="SubChapListBox" BorderThickness="0" Margin="20,0" ItemsSource="{Binding Path=chapters}" ItemContainerStyle="{StaticResource ListBoxItemStyle}">
<ListBox.ItemTemplate>
<DataTemplate>
<Expander Name="Expander1" ExpandDirection="Down" BorderThickness="0">
<Expander.Style>
<Style TargetType="Expander" BasedOn="{StaticResource ExpanderItemStyle}">
<Setter Property="Template" Value="{StaticResource WithToggleButton}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=chapters}" Value="{x:Null}">
<Setter Property="Template" Value="{StaticResource WithoutToggleButton}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Expander.Style>
<Expander.Header>
<BulletDecorator>
<Button Tag="{Binding}" Style="{StaticResource ResourceKey=BookPageStyle}" Click="SubchpaterButton_Click" Content="{Binding Path=name}"/>
</BulletDecorator>
</Expander.Header>
<StackPanel>
<ListBox x:Name="SubChapListBox" BorderThickness="0" Margin="20,0" ItemsSource="{Binding Path=chapters}" ItemContainerStyle="{StaticResource ListBoxItemStyle}">
<ListBox.ItemTemplate>
<DataTemplate>
<Expander Name="expander2" ExpandDirection="Down" BorderThickness="0" >
<Expander.Style>
<Style TargetType="Expander">
<Setter Property="Template" Value="{StaticResource WithToggleButton}"/>
<Style.Triggers>
<DataTrigger Binding="{Binding Path=chapters}" Value="{x:Null}">
<Setter Property="Template" Value="{StaticResource WithoutToggleButton}"/>
</DataTrigger>
</Style.Triggers>
</Style>
</Expander.Style>
<Expander.Header>
<BulletDecorator>
<Button Tag="{Binding}" Style="{StaticResource ResourceKey=BookPageStyle}" Click="SubchpaterButton_Click" Content="{Binding Path=name}"/>
</BulletDecorator>
</Expander.Header>
</Expander>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</Expander>
</DataTemplate>
</ListBox.ItemTemplate>
</ListBox>
</StackPanel>
</Expander.Content>
</Expander>
</DataTemplate>
</ItemsControl.ItemTemplate>
</ListBox>
</Grid>
</ScrollViewer>
</Grid>
结果
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