Hi,

You could set them from Xaml if you redefine both DiagramView and ScrollViewer template. Otherwise you could access them by overriding OnApplyTemplate in child class:

public class DiagramViewEx : DiagramView
{
    public override void OnApplyTemplate()
    {
        base.OnApplyTemplate();

        var scrollViewer = GetTemplateChild("PART_ScrollViewer") as ScrollViewer;
        if (scrollViewer != null)
        {
            scrollViewer.ApplyTemplate();

            var horizontal = scrollViewer.Template.FindName(
                "PART_HorizontalScrollBar", scrollViewer) as ScrollBar;
            var vertical = scrollViewer.Template.FindName(
                "PART_VerticalScrollBar", scrollViewer) as ScrollBar;

            if (horizontal != null)
                AutomationProperties.SetAutomationId(horizontal, "HorizontalScroll");
            if (vertical != null)
                AutomationProperties.SetAutomationId(vertical, "VerticalScroll");
        }
    }
} 

If you prefer Xaml and redefining templates, here's DiagramView's one:

<!-- DiagramView -->
<Style TargetType="{x:Type local:DiagramView}">
    <Setter Property="SnapsToDevicePixels" Value="True" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type local:DiagramView}">
                <ScrollViewer
                    x:Name="PART_ScrollViewer"
                    CanContentScroll="True"
                    HorizontalScrollBarVisibility="Auto"
                    Focusable="False">

                    <local:DiagramPresenter x:Name="PART_Presenter"
                        HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
                        VerticalAlignment="{TemplateBinding VerticalContentAlignment}"/>

                </ScrollViewer>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style> 

I'm seeing this as ScrollViewer template after selecting Edit Template command in VS designer:

<ControlTemplate x:Key="ScrollViewerTemplate1" TargetType="{x:Type ScrollViewer}">
    <Grid x:Name="Grid" Background="{TemplateBinding Background}">
        <Grid.ColumnDefinitions>
            <ColumnDefinition Width="*"/>
            <ColumnDefinition Width="Auto"/>
        </Grid.ColumnDefinitions>
        <Grid.RowDefinitions>
            <RowDefinition Height="*"/>
            <RowDefinition Height="Auto"/>
        </Grid.RowDefinitions>
        <Rectangle x:Name="Corner" Grid.Column="1" Fill="{DynamicResource {x:Static SystemColors.ControlBrushKey}}" Grid.Row="1"/>
        <ScrollContentPresenter x:Name="PART_ScrollContentPresenter" CanHorizontallyScroll="False" ContentTemplate="{TemplateBinding ContentTemplate}" CanVerticallyScroll="False" Grid.Column="0" Content="{TemplateBinding Content}" CanContentScroll="{TemplateBinding CanContentScroll}" Margin="{TemplateBinding Padding}" Grid.Row="0"/>
        <ScrollBar x:Name="PART_VerticalScrollBar" AutomationProperties.AutomationId="VerticalScrollBar" Cursor="Arrow" Grid.Column="1" Maximum="{TemplateBinding ScrollableHeight}" Minimum="0" Grid.Row="0" Value="{Binding VerticalOffset, Mode=OneWay, RelativeSource={RelativeSource Mode=TemplatedParent}}" ViewportSize="{TemplateBinding ViewportHeight}" Visibility="{TemplateBinding ComputedVerticalScrollBarVisibility}"/>
        <ScrollBar x:Name="PART_HorizontalScrollBar" AutomationProperties.AutomationId="HorizontalScrollBar" Cursor="Arrow" Grid.Column="0" Maximum="{TemplateBinding ScrollableWidth}" Minimum="0" Orientation="Horizontal" Grid.Row="1" Value="{Binding HorizontalOffset, Mode=OneWay, RelativeSource={RelativeSource Mode=TemplatedParent}}" ViewportSize="{TemplateBinding ViewportWidth}" Visibility="{TemplateBinding ComputedHorizontalScrollBarVisibility}"/>
    </Grid>
</ControlTemplate>
 

Regards,
Slavcho
Mindfusion

Hi,

Maybe you were seeing it from external ScrollViewer in older version.

DiagramView overrides OnCreateAutomationPeer since v4.1.6, to allow enumerating non-realized items. If you don't care about that, try overriding OnCreateAutomationPeer yourself to return the base FrameworkElementAutomationPeer, and hopefully it could find ScrollViewer from template and return its peer.

Our DiagramViewAutomationPeer returns ScrollViewer's peer too when requested via Scroll patternInterface:

override public object GetPattern(PatternInterface patternInterface)
{
	if (patternInterface == PatternInterface.Scroll)
	{
		if (View.ScrollViewer != null)
		{
			var scrollPeer = CreatePeerForElement(View.ScrollViewer);
			if (scrollPeer != null && scrollPeer is IScrollProvider)
			{
				scrollPeer.EventsSource = this;
				return (IScrollProvider)scrollPeer;
			}
		}
	}
... 

so maybe check if you can configure your tools to request that PatternInterface.

Let us know if still not working and our developer will debug using these tools.

Regards,
Slavcho
Mindfusion