帶有右對齊值的WPF TreeView

Question

我的wpf treeview有問題。它的代碼是這樣的：

<TreeView ItemsSource="{Binding Path=Items}" Grid.RowSpan="2" Grid.ColumnSpan="2"> 
     <TreeView.Resources> 
      <HierarchicalDataTemplate DataType="{x:Type m:MyTreeItem}" ItemsSource="{Binding Items}"> 
       <DockPanel LastChildFill="True"> 
        <TextBlock Text="{Binding Path=Value}" DockPanel.Dock="Right"/> 
        <TextBlock Text="{Binding Path=Display}" DockPanel.Dock="Left"/> 
       </DockPanel> 
      </HierarchicalDataTemplate> 
     </TreeView.Resources> 
    </TreeView> 

哪裏MyTreeItem是2點String類型的屬性（顯示和值）和MyTreeItem列表的簡單的類稱爲項。

我需要樹視圖來顯示所有'值'對齊的權利，同時保持項目'顯示'的樹列表，基於它的深度。

我已經嘗試將dockPanel設置爲固定寬度，但沒有奏效。

我想這樣做沒有任何C＃代碼，只是XAML。

在此先感謝。

Answer 1

如果我正確理解您的問題，您希望拉伸TreeViewItem s並將Value對齊到右側。要獲得TreeViewItem以彈性橫向展開，您需要編輯TreeViewItem的模板。這裏解釋的問題是：http://leecampbell.blogspot.com/2009/01/horizontal-stretch-on-treeviewitems.html

這是TreeViewItem的編輯版本。請注意，您必須添加引用PresentationFramework.Aero這個工作

樣品

<TreeView ItemsSource="{Binding Path=Items}" 
      Grid.RowSpan="2" 
      Grid.ColumnSpan="2" 
      ItemContainerStyle="{StaticResource StretchTreeViewItemStyle}"> 
    <TreeView.Resources> 
     <HierarchicalDataTemplate DataType="{x:Type m:MyTreeItem}" ItemsSource="{Binding Items}"> 
      <DockPanel LastChildFill="True"> 
       <TextBlock Text="{Binding Path=Value}" DockPanel.Dock="Right"/> 
       <TextBlock Text="{Binding Path=Display}" DockPanel.Dock="Left"/> 
      </DockPanel> 
     </HierarchicalDataTemplate> 
    </TreeView.Resources> 
</TreeView> 

StretchTreeViewItemStyle

<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> 
<Style x:Key="StretchTreeViewItemStyle" 
    TargetType="{x:Type TreeViewItem}" 
    xmlns:Microsoft_Windows_Themes="clr-namespace:Microsoft.Windows.Themes;assembly=PresentationFramework.Aero"> 
    <Setter Property="Background" Value="Transparent"/> 
    <Setter Property="HorizontalContentAlignment" Value="Stretch"/> 
    <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="*"/> 
        </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"> 
         <ContentPresenter x:Name="PART_Header" ContentSource="Header" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/> 
        </Border> 
        <ItemsPresenter x:Name="ItemsHost" 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> 

Answer 2

class StretchedTreeView : TreeView { 
    protected override void OnItemContainerStyleChanged(Style oldItemContainerStyle, Style newItemContainerStyle) { 
     base.OnItemContainerStyleChanged(oldItemContainerStyle, newItemContainerStyle); 
     newItemContainerStyle.Setters 
      .Add(new EventSetter(LoadedEvent, new RoutedEventHandler(TreeViewItem_Loaded))); 
    } 
    void TreeViewItem_Loaded(object sender, RoutedEventArgs e) { 
     TreeViewItem item = sender as TreeViewItem; 
     if (item == null) { 
      return; 
     } 
     ContentPresenter cp = FindVisualChild<ContentPresenter>(item); 
     cp.HorizontalAlignment = HorizontalAlignment.Stretch; 
     Border border = FindVisualChild<Border>(item, "Bd"); 
     border.SetValue(Grid.ColumnSpanProperty, 2); 
    } 
    static T FindVisualChild<T>(DependencyObject obj, string name = null) where T : DependencyObject { 
     for (int i = 0 ; i < VisualTreeHelper.GetChildrenCount(obj) ; i++) { 
      DependencyObject child = VisualTreeHelper.GetChild(obj, i); 
      if (child != null && child is T 
       && (name == null || !(child is FrameworkElement) || name == ((FrameworkElement) child).Name)) { 
       return (T) child; 
      } 
      else { 
       T childOfChild = FindVisualChild<T>(child, name); 
       if (childOfChild != null) { 
        return childOfChild; 
       } 
      } 
     } 
     return null; 
    } 
}