Different "LcRevitId" Value for different extraction Methods of ModelItem

[johann.haak]

I have been experiencing following issue:
Depending on the way I extract ModelItems from NavisWorks I get different amount of Information and exspecially different "LcRevitId" Values for the same ModelItem. For me it happens if I use CableTrayFittings. When I use Seach class I get the actual Revit Id:

If I use 

ModelItemCollection selectionModelItems = new ModelItemCollection();
Autodesk.Navisworks.Api.Application.ActiveDocument.CurrentSelection.SelectedItems.CopyTo(selectionModelItems);

I get a different Id for the same Element

Two Questions:
1) What is the Reason for this and why does it on ly happen to certain Element Categories: For example it does not happen for CableTrays
2) What I have been doing so far is Quering all the Items with the Search class and then to mapping the two modelItems, the only thing I found that might works is to check if the bounding boxes are the same. Are their any better options on how to map the ModelItems?

[naveen.kumar.t]

Hi @johann.haak ,

Could you please send me the non-confidential Navisworks sample file and step-by-step approach to reproduce the issue?

[johann.haak]

Hi, @naveen.kumar.t
sorry for not answering so long.
But I have a non confidential Navisworks files now.

Reproduction to the Issue is the following way:
1. Step Use Search functionality in Navisworks to select following ModelItem by Revit Id: "1679205"
As you can see in the picture the Revit Id shown in the Properties has following Value.

2.Step select ModelItem by clicking it over the UI:

Now here the RevitId has a diffrent Value.

Important: This only applies for cabletrayFitttings not for cable trays. So for non system families.

[naveen.kumar.t]

Hi @johann.haak ,

Thank you for the sample file.

I have asked the Navisworks Engineering team.

I will come back to you as soon as I receive a response from the Navisworks Engineering team.

[naveen.kumar.t]

One suggestion is to look at the Selection Tree. You may probably be picking a different item.

[naveen.kumar.t · Accepted solution]

Hi @johann.haak ,

I checked the selection tree. 

Looks like a 2 different items to me.

[johann.haak]

@naveen.kumar.t 
Thanks for helping out with this. In the end I can still not tell 100 percent why the ModelItem Hirachie goes deeper with Non System Families, but I feel this is the way our Revit Models work.
But more important with your Feedback i am now able to find the Instance of the ModelItem that references to the Revit Id, by looking through the selected ModelItems Ancestors.