iTwin
Presentation: Advanced instance filtering
Need a way to pass an expression + additional information about the class and/or related instances so they could be used in the expression.
The relatedInstances attribute is used for describing the paths to related property instances.
The selectClassName attribute is used to filter select instances based on their class. This also helps us cover the case when a single properties field is created from multiple differently named properties from different classes. In that case we'd create two instance filter definitions for each select class, each with a different expression targeting different properties. I don't like this approach too much, because in case of complex expressions, there would be a lot of duplication just to cover those special property fields..
