How can I add watermark on SyntaxEditor? ( using JavaScriptSyntaxLanguage )

Hi, I am using SyntaxEditor with JavaScriptSyntaxLanguage, and also want to add watermark on it.

Delightly I found a watermark sample code in the installed samples "Adornment 7 - watermark".

So I applied on my project but it didn't work. :(

I wonder that the watermark function is only worked on custom language not JavaScriptSyntaxLanguage.

Is my wondering right?

My sample codes follows,

this.SyntaxEditorObj.Document.Language = new JavaScriptSyntaxLanguage();
this.SyntaxEditorObj.Document.Language.RegisterService(new AdornmentManagerProvider<VictoriaWatermarkAdornmentManager>(typeof(VictoriaWatermarkAdornmentManager)));

VictoriaWatermarkAdornmentManager class is almost same as the installed sample.

public class VictoriaWatermarkAdornmentManager : AdornmentManagerBase<IEditorView>
{
	private static AdornmentLayerDefinition layerDefinition = new AdornmentLayerDefinition("Watermark", new Ordering(AdornmentLayerDefinitions.Selection.Key, OrderPlacement.After));
	private IAdornment watermarkAdornment;

	/////////////////////////////////////////////////////////////////////////////////////////////////////
	// OBJECT
	/////////////////////////////////////////////////////////////////////////////////////////////////////

	/// <summary>
	/// Initializes a new instance of the <c>WatermarkAdornmentManager</c> class.
	/// </summary>
	/// <param name="view">The view to which this manager is attached.</param>
	public VictoriaWatermarkAdornmentManager(IEditorView view)
		: base(view, layerDefinition)
	{
		// Only let this manager be active when the view has focus
		this.IsActive = view.HasFocus;

		// Create the watermark adornment
		this.watermarkAdornment = this.CreateWatermarkAdornment();

		// Attach to events
		view.TextAreaLayout += OnViewTextAreaLayout;
	}

	/////////////////////////////////////////////////////////////////////////////////////////////////////
	// NON-PUBLIC PROCEDURES
	/////////////////////////////////////////////////////////////////////////////////////////////////////

	/// <summary>
	/// Called when the <c>ViewTextAreaLayout</c> event occurs.
	/// </summary>
	/// <param name="sender">The sender of the event.</param>
	/// <param name="e">The <see cref="ActiproSoftware.Windows.Controls.SyntaxEditor.TextViewTextAreaLayoutEventArgs"/> 
	/// instance containing the event data.</param>
	private void OnViewTextAreaLayout(object sender, TextViewTextAreaLayoutEventArgs e)
	{
		// Determine the center of the text area viewport
		Rect textAreaViewportBounds = e.View.TextAreaViewportBounds;
		Point center = new Point(textAreaViewportBounds.Width / 2, textAreaViewportBounds.Height / 2);

		// Determine the center of the watermark element
		UIElement element = this.watermarkAdornment.VisualElement;
		TextBlock textBlock = element as TextBlock;
		if (textBlock == null)
			return;
		Point textBlockCenter = new Point(textBlock.ActualWidth / 2, textBlock.ActualHeight / 2);

		// Determine the watermark location
		Point watermarkLocation = new Point(center.X - textBlockCenter.X, center.Y - textBlockCenter.Y);

		// Set the watermark location
		watermarkAdornment.Location = watermarkLocation;
	}

	/// <summary>
	/// Creates the watermark adornment.
	/// </summary>
	/// <returns>The watermark adornment.</returns>
	private IAdornment CreateWatermarkAdornment()
	{
		// Create a UIElement for the watermark
		TextBlock textBlock = new TextBlock()
		{
			Text = "powered by TradeJs™",
			FontSize = 72,
			Foreground = new SolidColorBrush(Color.FromArgb(0x20, 0xff, 0x0, 0x0)),
		};

		// Add the UIElement to the adornment layer as an adornment
		return this.AdornmentLayer.AddAdornment(textBlock, new Point(), null, null);
	}

	/////////////////////////////////////////////////////////////////////////////////////////////////////
	// PUBLIC PROCEDURES
	/////////////////////////////////////////////////////////////////////////////////////////////////////

	/// <summary>
	/// Occurs when the manager is closed and detached from the view.
	/// </summary>
	/// <remarks>
	/// Overrides should release any event handlers set up in the manager's constructor.
	/// </remarks>
	protected override void OnClosed()
	{
		// Detach from events
		this.View.TextAreaLayout -= OnViewTextAreaLayout;

		// Remove any remaining adornments
		this.AdornmentLayer.RemoveAllAdornments();

		// Call the base method
		base.OnClosed();
	}
}