Stair Support Parameter Binding

[csds360]

Hi

I wanted to see if anybody could shed some light on this.

I have been having a problem with parameter binding to a particular category through the API. This is the 'Support' category that is a child of 'Stairs'.

Through the UI, this simply is done by checking this box:

When you get the category from the element in Revit via RevitLookup it returns:

Category of BuiltInCategory.OST_StairsStringerCarriage with .AllowsBoundParameters = True

 

When you get the category via

Category.GetCategory(Doc, BuiltInCategory.OST_StairsStringerCarriage) it returns:

Category of BuiltInCategory.OST_StairsSupports with .AllowBoundParameters = False

This is preventing attaching parameters to the element via the API (as can be done in the UI).

Does anybody know if there is a way round this, or is this in the API by design or possibly a bug? 

Any help would be greatly appreciated?

Many thanks.

@Anonymous @naveen.kumar.t@RPTHOMAS108 

[naveen.kumar.t]

Hi @csds360 ,

The development team is aware of this issue and they are working on it.

[csds360]

Hi @naveen.kumar.t 

Many thanks for your prompt response and clarification. 

[dev]

Just a remark - I am also encountering this issue for my company's Revit plug-in.

[aignatovich · Accepted solution]

Hi guys. Yes, I understand this is an old post, but this issue also affects the latest Revit 2022 version.

So the workaround could be something like this:

var col = FilteredElementCollector(doc);

var filter = new LogicalAndFilter(new ElementCategoryFilter(BuiltInCategory.OST_StairsStringerCarriage), new ElementIsElementTypeFilter());

var element = col.WherePasses(filter).FirstElement(); // At least one type exists even in empty model. Revit prevents deletion of the last element type of this category

var category = element.Category; // correct OST_StairsStringerCarriage category

[csds360]

Thank you @aignatovich. That did the trick.