c# - WPF - TreeView 隐藏展开图标(箭头)

Question

有没有办法隐藏所有 TreeView 的展开/折叠图标？我发现如果没有节点的项目，图标应该隐藏。但我想把它藏在树的任何地方。我只想在选择节点文本时伸展树(Splay Tree)(我已经实现了这个)。

Answer 1

您可以将这些样式添加到 Window 或 UserControl 资源:

<Window.Resources>               
    <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 Width="10"/>
                            <ColumnDefinition Width="Auto"/>
                            <ColumnDefinition Width="*"/>
                        </Grid.ColumnDefinitions>                            
                        <Grid.RowDefinitions>
                            <RowDefinition Height="Auto"/>
                            <RowDefinition/>
                        </Grid.RowDefinitions>                                                   
                        <Border 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"/>
                    </Grid>

                    <ControlTemplate.Triggers>
                        <Trigger Property="IsExpanded" Value="false">
                            <Setter TargetName="ItemsHost" Property="Visibility" Value="Collapsed"/>
                        </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>
                        <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>
</Window.Resources>