• Is this the correct way to solve the problem?
• Should this connection type be used for any of the other signals?

We should double check it, but it's possible that progress is the only signal "normally" emitted by an AddJob.
Btw I thought we were already using some Qt::DirectConnection elsewhere, but it seems we don't anymore.

I also tried to add

connect(archiveInterface(), &ReadOnlyArchiveInterface::progress, this, &CreateJob::onProgress);

at the beginning of CreateJob::doWork(), without direct connection, but this only fixes the progress for libzip :/

In D21403#470265, @elvisangelaccio wrote:

I also tried to add

connect(archiveInterface(), &ReadOnlyArchiveInterface::progress, this, &CreateJob::onProgress);

at the beginning of CreateJob::doWork(), without direct connection, but this only fixes the progress for libzip :/

I checked your solution and it fixes both plugins for me. Please check again.

I'm not sure what is going on to be honest. What do you think is the more correct solution?

In D21403#473053, @rthomsen wrote:

I'm not sure what is going on to be honest. What do you think is the more correct solution?

I don't like either, to be honest, as they are both workarounds. The actual problem is that CreateJob starts two different threads, with two "nested" event loops.

This is wrong and should be fixed on master. For 19.04 I submitted D21686 as temporary fix...