WPF

public class CDSceneSelectorEditor : DialogPropertyValueEditor
{
    public CDSceneSelectorEditor()
    {

        string template = 
            @"<DataTemplate xmlns='http://schemas.microsoft.com/winfx/2006/xaml/presentation'
                            xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'
//                          xmlns:pe='clr-namespace:System.Activities.Presentation.PropertyEditing;assembly=System.Activities.Presentation'>
                <DockPanel LastChildFill='True'>
                <pe:EditModeSwitchButton TargetEditMode='Dialog' Name='EditButton' 
                                         DockPanel.Dock='Right' Content='...' />
                <TextBlock Text='Picture' Margin='2,0,0,0' 
                           VerticalAlignment='Center'/>
            </DockPanel>
        </DataTemplate>";

        try
        {
            using (var sr = new MemoryStream(Encoding.UTF8.GetBytes(template)))
            {
                this.InlineEditorTemplate = (DataTemplate)(XamlReader.Load(sr));
            }
        }
        catch (Exception ex)
        {
            if (ex != null) {}
        }
    }
}

public class CDSceneSelectorEditor : DialogPropertyValueEditor
{
    public CDSceneSelectorEditor()
    {
        var button = new FrameworkElementFactory(typeof(EditModeSwitchButton))
                         { Name = "EditButton"     };
        button.SetValue(DockPanel.DockProperty, Dock.Right);
        button.SetValue(EditModeSwitchButton.TargetEditModeProperty, 
                        PropertyContainerEditMode.Dialog);
        button.SetValue(EditModeSwitchButton.ContentProperty, " ... ");
        button.SetValue(TextBlock.MarginProperty, new Thickness(0,0,3,0));

        var image  = new FrameworkElementFactory(typeof(Image))
                         { Name = "ThumbnailImage" };
        image.SetValue(Image.StretchProperty, 
                       System.Windows.Media.Stretch.Uniform);

        var panel  = new FrameworkElementFactory(typeof(DockPanel));
        panel.AppendChild(button);
        panel.AppendChild(image);

        DataTemplate template = new DataTemplate();
        template.VisualTree = panel;
        this.InlineEditorTemplate = template;
    }
}

<?xml version="1.0" encoding="utf-8"?>
<ArrayOfFolderEntity xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <FolderEntity Id="0" FolderName="Projects" Description="">
    <Folders>
      <FolderEntity Id="3" FolderName="Folder 1" Description="Folder 1 Desc ">
        <Folders />
        <Files>
          <FileEntity Id="1" FileName="File A" Description="File A Desc " />
          <FileEntity Id="2" FileName="File B" Description="File B Desc " />
        </Files>
      </FolderEntity>
      <FolderEntity Id="6" FolderName="Folder 2" Description="Folder 2 Desc ">
        <Folders />
        <Files>
          <FileEntity Id="4" FileName="File C" Description="File C Desc " />
          <FileEntity Id="2" FileName="File B" Description="File B Desc " />
        </Files>
      </FolderEntity>
    </Folders>
    <Files />
  </FolderEntity>
</ArrayOfFolderEntity>

<TreeView x:Name="tvwItems"
            BorderThickness="0"
            Background="Transparent"
            Grid.Row="1"
            Grid.Column="0"
            Margin="0,2,0,2"
            ItemsSource="{Binding Folders}">
            
    <TreeView.Resources>
        <HierarchicalDataTemplate DataType="{x:Type entities:FolderEntity}" 
                                    ItemsSource="{Binding Folders}">
            <TextBlock Text="{Binding Path=FolderName}" />
        </HierarchicalDataTemplate>
        <DataTemplate DataType="{x:Type entities:FileEntity}" >
            <TextBlock Text="{Binding Path=FileName}" />
        </DataTemplate>
    </TreeView.Resources>
            
</TreeView>

Projects
  Folder 1
  Folder 2

<!--Context Menu Style-->


<LinearGradientBrush x:Key="MenuItemSelectionFill" EndPoint="0,1" StartPoint="0,0">
    <GradientStop Color="#34C5EBFF" Offset="0"/>
    <GradientStop Color="#3481D8FF" Offset="1"/>
</LinearGradientBrush>

<!--Sub Menu Item-->

<Style>
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate x:Key="{ComponentResourceKey ResourceId=SubmenuItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}" TargetType="{x:Type MenuItem}">
                <Grid>
                    <Rectangle x:Name="Bg" Fill="{TemplateBinding Background}" RadiusY="2" RadiusX="2" Stroke="{TemplateBinding BorderBrush}" StrokeThickness="1"/>
                    <Rectangle x:Name="InnerBorder" Margin="5" RadiusY="2" RadiusX="2"/>
                    <Grid>
                        <Grid.ColumnDefinitions>
                            <ColumnDefinition Width="32" SharedSizeGroup="MenuItemIconColumnGroup"/>
                            <ColumnDefinition Width="*" />

                        </Grid.ColumnDefinitions>

                        <ContentPresenter Grid.Column="0" x:Name="Icon" Margin="0"  VerticalAlignment="Center" ContentSource="Icon"/>
                        <ContentPresenter Grid.Column="1" Margin="10" ContentSource="Header" VerticalAlignment="Center" RecognizesAccessKey="True"/>

                    </Grid>
                </Grid>

                <ControlTemplate.Triggers>
                    <Trigger Property="Icon" Value="{x:Null}">
                        <Setter Property="Visibility" TargetName="Icon" Value="Collapsed"/>
                    </Trigger>
                    <Trigger Property="IsHighlighted" Value="true">
                        <Setter Property="Fill" TargetName="Bg" Value="{StaticResource MenuItemSelectionFill}"/>
                        <Setter Property="Stroke" TargetName="Bg" Value="#8071CBF1"/>
                        <Setter Property="Stroke" TargetName="InnerBorder" Value="#40FFFFFF"/>
                    </Trigger>
                </ControlTemplate.Triggers>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>


<!--Menu Item Style-->

<Style x:Key="{x:Type MenuItem}" TargetType="MenuItem" BasedOn="{StaticResource BaseControlStyle}">
    <Style.Triggers>

        <Trigger Property="Role" Value="SubmenuItem">
            <Setter Property="Padding" Value="5"/>
            <Setter Property="Background" Value="#F0F0F0"/>
            <Setter Property="Template" Value="{DynamicResource {ComponentResourceKey ResourceId=SubmenuItemTemplateKey, TypeInTargetAssembly={x:Type MenuItem}}}"/>
        </Trigger>

    </Style.Triggers>
</Style>