How to Show GUI and work on background

[anda_skoa]

Then? How can I derive from both?

Didn't I just write that this is not possible?
How does asking how to do it make any sense?
Obviously there is no "how".

Do you mean that I have to make 2 projects and then unify them with a process??

That is an option.
You can also have a project that contains two exectuables.
The template for a multi target project is called "subdirs".

If yes can you put the code or the idea more or less of it? I can't understand how can the code be.

The idea is two have two programs:
1) a GUI that needs to be event driven to stay responive
2) a simple non-GUI worker program that can block until it is done

Then have the GUI program run the non-GUI program using QProcess.

Multi-Process is an alternative to multithreading with slightly different properties.

Depends a lot on what that parallel task is, how much it needs to share data with the UI and how often it needs to communicate.

Cheers,
_