带拉伸的 TreeViewItem

Question

我想创建一个 WPF TreeView，其中包含可拉伸以填充可用空间的 TreeViewItems。我以此为指导修改了 TreeViewItem 模板：https://social.msdn.microsoft.com/Forums/vstudio/en-US/cabcb3ba-80c0-4367-85b7-9b55adc81e65/stretch-treeview-items ?forum=wpf这很有效，因为我希望右侧的一个字符网格组件右对齐，并且长 TextBlock 占用可用空间 - 请参阅下面的代码，其中我的 TreeViewItems 之一的标题是网格。

但是，当我通过将右侧拖动到左侧来调整窗口大小时，当没有足够的空间容纳所有网格组件时，我期望长的 TextBlock 内容为“长长的，... " 开始缩小宽度，但右侧的 TextBlock 却被右侧窗口边缘切断。

如果我创建一个具有网格的全新示例，并将上面提到的网格放入其中一个网格单元格中（本质上是模拟 TreeView 模板中使用的网格），那么它会按照我的预期调整大小：当我调整大小时，TextBlock 的宽度会缩小。

有什么想法可以对 TreeViewItem 模板或我指定的标题进行哪些更改以获得我想要的大小调整行为？

<Window x:Class="TreeViewSimple3.MainWindow"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    xmlns:local="clr-namespace:TreeViewSimple3"
    mc:Ignorable="d"
    Title="MainWindow" Height="350" Width="525">

<Window.Resources>
    <ControlTemplate x:Key="TreeViewItemStretchControlTemplate" 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" ClickMode="Press" IsChecked="{Binding IsExpanded, RelativeSource={RelativeSource TemplatedParent}}">
                <ToggleButton.Style>
                    <Style 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" Width="16">
                                        <Path x:Name="ExpandPath" Data="M0,0 L0,6 L6,0 z" Fill="Transparent" Stroke="#FF989898">
                                            <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="#FF595959"/>
                                            <Setter Property="Stroke" TargetName="ExpandPath" Value="#FF262626"/>
                                        </Trigger>
                                        <Trigger Property="IsMouseOver" Value="True">
                                            <Setter Property="Stroke" TargetName="ExpandPath" Value="#FF1BBBFA"/>
                                            <Setter Property="Fill" TargetName="ExpandPath" Value="Transparent"/>
                                        </Trigger>
                                        <MultiTrigger>
                                            <MultiTrigger.Conditions>
                                                <Condition Property="IsMouseOver" Value="True"/>
                                                <Condition Property="IsChecked" Value="True"/>
                                            </MultiTrigger.Conditions>
                                            <Setter Property="Stroke" TargetName="ExpandPath" Value="#FF262626"/>
                                            <Setter Property="Fill" TargetName="ExpandPath" Value="#FF595959"/>
                                        </MultiTrigger>
                                    </ControlTemplate.Triggers>
                                </ControlTemplate>
                            </Setter.Value>
                        </Setter>
                    </Style>
                </ToggleButton.Style>
            </ToggleButton>
            <Border x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Grid.Column="1" Grid.ColumnSpan="2" Padding="{TemplateBinding Padding}" SnapsToDevicePixels="True">
                <ContentPresenter x:Name="PART_Header" ContentSource="Header"
                HorizontalAlignment="{TemplateBinding Control.HorizontalContentAlignment}"
                SnapsToDevicePixels="{TemplateBinding UIElement.SnapsToDevicePixels}"/>

            </Border>
            <ItemsPresenter x:Name="ItemsHost" Grid.ColumnSpan="2" Grid.Column="1" Grid.Row="1"/>
        </Grid>
        <ControlTemplate.Triggers>
            <Trigger Property="TreeViewItem.IsExpanded" Value="false">
                <Setter TargetName="ItemsHost" Property="UIElement.Visibility" Value="Collapsed"/>
            </Trigger>
            <Trigger Property="ItemsControl.HasItems" Value="false">
                <Setter TargetName="Expander" Property="UIElement.Visibility" Value="Hidden"/>
            </Trigger>
            <Trigger Property="TreeViewItem.IsSelected" Value="true">
                <Setter TargetName="Bd" Value="{DynamicResource {x:Static SystemColors.HighlightBrushKey}}"
                    Property="Border.Background"/>
                <Setter Value="{DynamicResource {x:Static SystemColors.HighlightTextBrushKey}}"
                    Property="Control.Foreground"/>
            </Trigger>
            <MultiTrigger>
                <MultiTrigger.Conditions>
                    <Condition Property="TreeViewItem.IsSelected" Value="true"/>
                    <Condition Property="TreeViewItem.IsSelectionActive" Value="false"/>
                </MultiTrigger.Conditions>
                <Setter TargetName="Bd"
                    Value="{DynamicResource {x:Static SystemColors.InactiveSelectionHighlightBrushKey}}"
                    Property="Border.Background"/>
                <Setter Value="{DynamicResource {x:Static SystemColors.InactiveSelectionHighlightTextBrushKey}}"
                    Property="Control.Foreground"/>
            </MultiTrigger>
            <Trigger Property="UIElement.IsEnabled" Value="false">
                <Setter Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}" Property="Control.Foreground"/>
            </Trigger>
        </ControlTemplate.Triggers>
    </ControlTemplate>
</Window.Resources>

<TreeView>
    <TreeViewItem Header="Parent" Template="{StaticResource TreeViewItemStretchControlTemplate}" HorizontalContentAlignment="Stretch">
        <TreeViewItem Template="{StaticResource TreeViewItemStretchControlTemplate}" HorizontalContentAlignment="Stretch">
            <TreeViewItem.Header>
                <Grid>
                    <Grid.ColumnDefinitions>
                        <ColumnDefinition Width="*"/>
                        <ColumnDefinition Width="Auto"/>
                    </Grid.ColumnDefinitions>
                    <TextBlock Grid.Column="0" Text="A long, long, long, long, long, long, long label."/>
                    <StackPanel Grid.Column="1" Orientation="Horizontal">
                        <TextBlock Text="A"/>
                        <TextBlock Text="B"/>
                        <TextBlock Text="C"/>
                        <TextBlock Text="D"/>
                    </StackPanel>
                </Grid>
            </TreeViewItem.Header>
        </TreeViewItem>
    </TreeViewItem>
</TreeView>

Answer 1

当我尝试代码示例并减小窗口大小时，TreeView 显示水平滚动条（因为它的模板中不仅有 Grid，还有 ScrollViewer）

尝试以下设置：

<TreeView ScrollViewer.HorizontalScrollBarVisibility="Disabled"> 

禁用滚动

<TextBlock TextWrapping="Wrap" Grid.Column="0" ...> 

启用自动换行。