I'm using a TreeStore with ajax proxy and XML reader to populate NestedList. It all works fine, but I need to modify the data that comes from the server before it is uploaded into the store model (cut out unneeded nodes, add/modify attributes etc).

Where is the best place to do that? I think I would need 'rawData' from XmlReader, modify it somewhere and put it back into processing? Can someone point me in the right direction on how to do that?