[vtkusers] vtkXMLImageDataReader ProgressEvent

[Slobodan Miskovic]

Hallo folks,
I'm having troubles geting progress update from vtkXMLImageDataReader.
I've defined an observer class as

class ProgressObserver : public vtkCommand {
public:
	static ProgressObserver* New() {
		return new ProgressObserver;
	}

	virtual void Execute(vtkObject* caller, unsigned long, void *callData) {
		std::cout << "!" << std::endl;
	}
};

and have it connected to the reader as

reader->AddObserver(vtkCommand::ProgressEvent, ProgressObserver::New());

but i only get one call of the execute method, conciding with the end
of file loading. Is xml reader supposed to dispatch progress events?
And if so, how may i get the current progress in the Execute method
(presumably some trickery with callData). This is happening on VTK4.2

Thanks in advance, Slobodan