[SOLVED]Communication between QRunnable and main thread

musimbate

Hi,
I was looking into the ThreadPool threading option in Qt and just realized that QRunnable doesn't inherit QObject so you can't send signals with it .The only working option I have from "here":http://www.qtcentre.org/threads/37340-Communication-between-QRunnable-and-main-thread is embedding a QObject member and sending the signal with it .

Is there any other way you have guys of communicating with the GUI thread?

Thanks.

andreyc

They have another suggestion, a multiple inheritance. Have you tried it.
@
class MyRunnable : public QObject, public QRunnable
{
...
};
@

musimbate

Thanks for the quick reply,
I was trying using :
@

class MyRunnable : public QRunnable, public QObject
{
...
};

@

And it gave those metaobject errors and unresolved symbols.But inheriting QObject first is working .Any Idea why we have to inherit QObject first here?

Also I how does one go about the postEvent solution suggested at that link.

Thanks.

andreyc

[quote author="musimbate" date="1396759690"]Any Idea why we have to inherit QObject first here?
[/quote]

One of the "moc limitations":http://qt-project.org/doc/qt-5/moc.html#multiple-inheritance-requires-qobject-to-be-first

andreyc

[quote author="musimbate" date="1396759690"]
Also I how does one go about the postEvent solution suggested at that link.
[/quote]

You can create your own QEvent (or inherited from QEvent) event-object and send it to QObject based object using
@
QCoreApplication::postEvent()
@

You can postEvent from any object not only QObject based. The receiver of the object must be QObject based.

More "info":http://qt-project.org/doc/qt-5/eventsandfilters.html#sending-events
And here is a simple "example":http://qt-project.org/doc/qt-5/qtwidgets-statemachine-pingpong-example.html

gyll

If you're ready to use Qt only as an OS interface (GUI, sockets, whatever), and clearly separate your app from the Qt interface, i'll publish a multi-threading framework in a week or two. The code works, but i still have to finish the documentation, and i expect this to take me a couple of weeks or so. If you wanna check out what the lib does, the current state of the doc is here: http://www.itgroup.ro/libposif-app-brief.pdf

musimbate

@andreyc:

Thanks ,the info you provided just answered my questions.

@gyll :

Will certainly take the time to look into that lib.Keep it up.

gyll

@musimbate: ok, stay subscribed to this forum thread and i'll drop a line here with the details when i'll publish it (it'll prolly be on sourceforge, but ain't sure yet).

Cheers!

gyll

well, it took a while, but here it is: http://libagents.sourceforge.net/

musimbate

Looking good.