IFCAPI::PropertyAccessor::GetAttributes issue in custom add‑on

larsr — Tue, 28 Jul 2026 13:30:27 GMT

Hello!

Does the new IFCAPI have any prerequisites that need to be set in order to be used? The code provided below, if added to the example project IFC_Test, will print:

TestApi(): 1
TestApi(): 2
TestApi(): 3
Number of attributes: 6
Attribute Name0: GlobalId
Attribute Name0: Name
Attribute Name0: Tag
Attribute Name0: PredefinedType

However, the same code in my add‑on returns 0 attributes:

TestApi(): 1
TestApi(): 2
TestApi(): 3
Number of attributes: 0

Archicad version: 29.2.0 (5003)
SDK version: WIN.29.3100

Test function:

void TestApi() { GS::Array<API_Neig> aSelection; API_SelectionInfo rSelectionInfo = {}; ACAPI_Selection_Get(&rSelectionInfo, &aSelection, false); for (auto& rNeig : aSelection) { API_Elem_Head head{}; head.guid = rNeig.guid; auto objectID = IFCAPI::GetObjectAccessor().CreateElementObjectID(head); // DBPrintf("TestApi(): 1\n"); if (objectID.IsErr()) { ACAPI_WriteReport("TestApi(): CreateElementObjectID failed for element ", true); return; } // IFCAPI::PropertyAccessor propertyAccessor = IFCAPI::PropertyAccessor(objectID.Unwrap()); auto properties = propertyAccessor.GetAttributes(); if (properties.IsErr()) { ACAPI_WriteReport("TestApi(): GetAttributes failed for element", true); return; } DBPrintf("TestApi(): 2\n"); // auto oIfcAttributes = properties.Unwrap(); DBPrintf("TestApi(): 3\n"); DBPrintf("Number of attributes: %zu\n", oIfcAttributes.size()); // for (auto& rIfcAttribute : oIfcAttributes) { if (rIfcAttribute.GetName().IsEmpty()) continue; // if (!rIfcAttribute.GetValue().has_value()) continue; // DBPrintf("Attribute Name0: %s\n", rIfcAttribute.GetName().ToCStr().Get()); } } }

Operating system used: Windows 11 25H2

topic IFCAPI::PropertyAccessor::GetAttributes issue in custom add‑on in Archicad C++ API

IFCAPI::PropertyAccessor::GetAttributes issue in custom add‑on