TreeViewItem实现整行选中 (两种用法)

用法一

 <ResourceDictionary xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
                     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
     <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=""/>
         <Setter Property="Height" Value=""/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="{x:Type ToggleButton}">
                     <Border Background="Transparent" Height="" Padding="5,5,5,5" Width="">
                         <Path x:Name="ExpandPath" Data="{StaticResource TreeArrow}" Fill="Transparent" Stroke="#FF989898">
                             <Path.RenderTransform>
                                 <RotateTransform Angle="" CenterY="" CenterX=""/>
                             </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="" CenterY="" CenterX=""/>
                                 </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 TargetType="{x:Type TreeViewItem}">
         <Setter Property="Background" Value="Transparent"/>
         <Setter Property="HorizontalContentAlignment" Value="{Binding HorizontalContentAlignment, RelativeSource={RelativeSource AncestorType={x:Type ItemsControl}}}"/>
         <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="{x:Null}"/>
         <Setter Property="Template">
             <Setter.Value>
                 <ControlTemplate TargetType="{x:Type TreeViewItem}">
                     <Grid>
                         <Grid.ColumnDefinitions>
                             <ColumnDefinition  Width=""/>
                             <ColumnDefinition/>
                         </Grid.ColumnDefinitions>
                         <Grid.RowDefinitions>
                             <RowDefinition/>
                             <RowDefinition/>
                         </Grid.RowDefinitions>
                         <Border Grid.ColumnSpan="" Margin="-1600,0,0,0"  x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}"  SnapsToDevicePixels="true"/>
                         <ToggleButton  x:Name="Expander" ClickMode="Press" IsChecked="{Binding IsExpanded, RelativeSource={RelativeSource TemplatedParent}}" Style="{StaticResource ExpandCollapseToggleStyle}"/>
                         <ContentPresenter Grid.Column="" x:Name="PART_Header" ContentSource="Header" HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                         <ItemsPresenter  x:Name="ItemsHost" Grid.ColumnSpan="" Grid.Column="" Grid.Row=""/>

                     </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="#FF404040" />
                             <Setter Property="Background" TargetName="Expander" Value="#FF404040"/>
                         </Trigger>
                         <MultiTrigger>
                             <MultiTrigger.Conditions>
                                 <Condition Property="IsSelected" Value="true"/>
                                 <Condition Property="IsSelectionActive" Value="false"/>
                             </MultiTrigger.Conditions>
                             <Setter Property="Background" TargetName="Bd" Value="#FF404040"/>

                             <Setter Property="Background" TargetName="Expander" Value="#FF404040"/>
                         </MultiTrigger>
                         <Trigger Property="IsEnabled" Value="false">
                             <Setter Property="Foreground" Value="{DynamicResource {x:Static SystemColors.GrayTextBrushKey}}"/>
                         </Trigger>
                     </ControlTemplate.Triggers>
                 </ControlTemplate>
             </Setter.Value>
         </Setter>
     </Style>

 </ResourceDictionary>

这种用法只能显示背景，无法显边框 ，原因在于：

<Border Grid.ColumnSpan="2" Margin="-1600,0,0,0"  x:Name="Bd" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}"  SnapsToDevicePixels="true"/>  中的margin设置成-1600;无法精确的设置margin

方法二（转截没有确正可行性）

方法更可行，但操作困难些

记得原来做Winfrom通过Item的Bounds可以获得整行的区域，但是在WPF中进行了几个布局方式都没能成功！
VS中的解决方案效果布局如下：

这样在第一行第二列方式Border控件，此为选中区域。而如果要实现右侧系统的效果，必须要在选中区域的时候补齐第二行第一列的宽度，但是如果在TreeViewItem的Template不设置子节点列表缩进的话，将无法定位子节点列表缩进！
对比了Winform的TreeNode类型有两个关键的属性：FullPath和Level。只要知道一个就可以根据Indent算出相应的缩进宽度，从这样的思路上，这个Item布局结构就要更改如下了：
 
代码结构如下：

<StackPanel>

<Border x:Name=”itemBorder”>

<Grid>

<Grid.ColumnDefinitions>

<ColumnDefinitions Width=”19” />

<ColumnDefinitions Width=”*” />

</Grid.ColumnDefinitions>

<Path x:Name=”TreeArrow” Grid.Column=”0” />

<ContentPresenter ContentSource=”Header” Grid.Column=”1”  />

</Grid>

</Border>

<ItemsPresenter x:Name="ItemsHost" />

</StackPanel>

可是此时的子节点列表没有缩进怎么办？
做几个预备动作，在TreeViewItem里面有一个TreeNode的特殊特性，叫做Level，获得节点所在的层级，在这里我做了个Extensions类：

用来获得TreeViewItem在TreeView里面的层级深度。然后就是怎么将缩进的绑定到它该在的地方了！

在上面那段TreeViewItem的Template代码里面的itemBorder就是节点项的整体范围了，如果我们想让选中边框始终保持Aero样式中满行选中的状态就只能在itemBorder中的Grid上做手脚了，上面扩展了TreeViewItem对象，可以获取的到层级深度，而缩进值则等于节点层级和缩进值的乘积，而应用缩进值需要实现一个缩进的转换类型方法：

 namespace WJ.Controls.Functions
 {
     public class IndentConverte : IValueConverter
     {
         public int Indent { get; set; }
         public object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
         {
             var item = value as TreeViewItem;
             if (null == item)
                 return new Thickness();
             int i = Indent * this.GetLevels(item);
             return new Thickness(Indent *( this.GetLevels(item) * - ), , , );
         }

         public object ConvertBack(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
         {
             throw new NotImplementedException();
         }

         public  int GetLevels(TreeViewItem item)
         {
             FrameworkElement elem = item;
             while (elem.Parent != null)
             {

                 var tvi = elem.Parent as TreeViewItem;
                 if (null != tvi)
                     return this.GetLevels(tvi) + ;

                 elem = elem.Parent as FrameworkElement;

             }
             return ;
         }
     }
 }

然后就是改造上一段模板内容。完整代码如下：

<Style TargetType="{x:Type TreeViewItem}" x:Key="aaa">
       <Setter Property="FocusVisualStyle" Value="{StaticResource TreeViewItemFocusVisual}"/>
       <Setter Property="Template">
           <Setter.Value>
               <ControlTemplate TargetType="{x:Type TreeViewItem}">
                   <ControlTemplate.Resources>
                      <o2ds:IndentConverter Indent="19" x:Key="indentConverter" />
                   </ControlTemplate.Resources>
                   <StackPanel>
                       <Border Name="itemBackground" Background="{TemplateBinding Background}"
                                BorderBrush="{TemplateBinding BorderBrush}"
                                BorderThickness="{TemplateBinding BorderThickness}"
                                Padding="{TemplateBinding Padding}">
                           <Grid Margin="{Binding Converter={StaticResource indentConverter},RelativeSource={RelativeSource TemplatedParent}}">
                               <Grid.ColumnDefinitions>
                                   <ColumnDefinition Width="19" />
                                   <ColumnDefinition />
                               </Grid.ColumnDefinitions>
                               <ToggleButton Grid.Column="0" x:Name="ArrowButton" Style="{StaticResource TreeViewArrowButtonStyle}"
                                             IsChecked="{Binding Path=IsExpanded, RelativeSource={RelativeSource TemplatedParent}}"
                                             ClickMode="Press" />
                               <ContentPresenter Grid.Column="1" x:Name="PART_Header" ContentSource="Header"
                                                 HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}" />
                           </Grid>
                       </Border>
                       <ItemsPresenter x:Name="ItemsHost" />
                   </StackPanel>

<ControlTemplate.Triggers>

Trigger something…
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>