How to draw only focus rectangle when selecting multiple nodes without displaying highlighting colors in WinForms TreeViewAdv?

this.treeViewAdv1.SelectedNodeBackground = new Syncfusion.Drawing.BrushInfo(Color.Transparent);
void treeViewAdv1_NodeBackgroundPaint(object sender, TreeNodeAdvPaintBackgroundEventArgs e)
{
   if(this.treeViewAdv1.SelectedNodes.Count!=0)
   {
      foreach(TreeNodeAdv treenode in treeViewAdv1.SelectedNodes)
      {
         using (Pen focusPen = new Pen(Color.Black))
         {
             focusPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dot;
             Rectangle focusBounds = treenode.DragCueBounds;
             focusBounds.Size = new Size(focusBounds.Width - 1, focusBounds.Height-1);
             e.Graphics.DrawRectangle(focusPen, focusBounds);
         }
      }
   }
}

Me.treeViewAdv1.SelectedNodeBackground = New Syncfusion.Drawing.BrushInfo(Color.Transparent)
Private Sub treeViewAdv1_NodeBackgroundPaint(ByVal sender As Object, ByVal e As TreeNodeAdvPaintBackgroundEventArgs)
   If Me.treeViewAdv1.SelectedNodes.Count<>0 Then
      For Each treenode As TreeNodeAdv In treeViewAdv1.SelectedNodes
          Using focusPen As Pen = New Pen(Color.Black)
              focusPen.DashStyle = System.Drawing.Drawing2D.DashStyle.Dot
              Dim focusBounds As Rectangle = treenode.DragCueBounds
              focusBounds.Size = New Size(focusBounds.Width - 1, focusBounds.Height-1)
              e.Graphics.DrawRectangle(focusPen, focusBounds)
          End Using
      Next treenode
   End If
End Sub