Hello Morgan, 

I am just checking if my last reply was helpful for you. 

If you require any further assistance, please do not hesitate to ask.

Just know I got the solution for same. Thanks for looking into it. 

But, Why is Visibility property binding not working, whereas IsExdpanded propertybinding is working

     <Style TargetType="{x:Type igDP:DataRecordPresenter}">
                    <Setter Property="HorizontalAlignment" Value="Left"/>
                    <Setter Property="BorderBrush" Value="Black"/>
                    <Setter Property="BorderThickness" Value="2"/>
                    <Setter Property="Visibility" Value="{Binding RelativeSource={RelativeSource Self}, NotifyOnSourceUpdated=True, NotifyOnTargetUpdated=True, UpdateSourceTrigger=PropertyChanged, Mode=OneWay, Path=Record.DataItem.Visible, Converter={StaticResource _visibilityConverter}}"/>
                    <Setter Property="IsExpanded" Value="{Binding RelativeSource={RelativeSource Self}, Path=Record.DataItem.Expanded, Mode=TwoWay, NotifyOnSourceUpdated=True, NotifyOnTargetUpdated=True, UpdateSourceTrigger=PropertyChanged}"/>
                    <!--<EventSetter Event="RequestBringIntoView" Handler="DRPloaded"/>-->
                </Style>

public class VisibilityConverter : ConverterBase
  {
    public VisibilityConverter() : base()
    {
    }
 
    public bool CollapsedWhenHidden
    {
      get
      {
        return _collapsedWhenHidden;
      }
      set
      {
        _collapsedWhenHidden = value;
      }
    }
 
    public override object Convert(object value, Type targetType, object parameter, CultureInfo culture)
    {
      if (value is bool && Object.Equals(targetType, typeof(Visibility)))
      {
        return ((bool)value ? Visibility.Visible : (_collapsedWhenHidden ? Visibility.Collapsed : Visibility.Hidden));
      }
      else
      {
        return null;
      }
    }
 
    public override object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture)
    {
      if (value is Visibility  && Object.Equals(targetType, typeof(bool)))
      {
        return ((Visibility)value == Visibility.Visible);
      }
      else
      {
        return null;
      }
    }
 
    private bool _collapsedWhenHidden = true;
  }

Code behind :

foreach (var treeNodeRole in ExceptionChecksModel.Items)
              {
                foreach (var treeNodeReviewItemType in treeNodeRole.ReviewItemTypes)
                {
                  foreach (var treeNodeCheckse in treeNodeReviewItemType.TreeNodeChecks)
                  {
                    bool isTreeNodeChecksOpen = // some logic (tru or false)
                    treeNodeCheckse.Expanded = isTreeNodeChecksOpen;
                    treeNodeCheckse.Visible = isTreeNodeChecksOpen;
 
                    treeNodeReviewItemType.Expanded = isTreeNodeChecksOpen;
                    treeNodeReviewItemType.Visible = isTreeNodeChecksOpen;
 
                    treeNodeRole.Expanded = isTreeNodeChecksOpen;
                    treeNodeRole.Visible = isTreeNodeChecksOpen;
                  }
                }
              }

Hello Anant,

Thank you for posting! 

I have been looking into your code but I am not completely sure I understood your scenario correctly. When do you use this _checksTree_AssigningFieldLayoutToItem method that you have provided as your code behind logic? Does this accumulation occur only when you are scrolling? Could you send me a sample project that is demonstrating the issue you are having? These will help me investigate it further and provide you with a better solution. Thank you in advance.

PLease attached the Xaml + Codebehind.

Pelase suggest some good solution. that Accumulation looks annoying.

Thanks