How to use separate threads for pushbuttons in QT (like SwingWorker in Java)

[anda_skoa]

Why do you state that I connect before the start of thread

No, I said you should connect before starting.

as it is obvious from that excerpt of code that R->start(); then connect(R,finished...)

Exactly.
Start before connect, i.e. the wrong way around.

Cheers,
_