Executing slot on every application's event loop iteration

Question

How can I call my slot on every iteration of application's event loop? Only way I know is to use QTimer and on every timeout (every millisecond) signal I can call my slot. But I don't like this option, it looks like workaround.

Any suggestions how to do this more correctly?

Your QTimer can have a timeout of 0, which will run once per event loop instead of once per millisecond, which will only *probably* run once per event loop. :-) Still a bit of a workaround, though. — Daniel Gallagher, Feb 26 '11 at 00:53
Yes, I know this and I am using it now, but it is not what I want. — asmodan, Feb 26 '11 at 11:22

score 3 · Accepted Answer · answered Feb 26 '11 at 15:40

From the Qt 4.7 QCoreApplication::exec() documentation:

To make your application perform idle processing (i.e. executing a special function whenever there are no pending events), use a QTimer with 0 timeout. More advanced idle processing schemes can be achieved using processEvents().

So your approach is what is prescribed. Look at QCoreApplication::processEvents() for more control over the event loop.

score 0 · Answer 2 · answered May 10 '11 at 15:10

0

You could also take a look at using the installEventFilter method on QCoreApplication::instance() object. This would allow you access to ALL events before they were processed for all widgets in your application.

answered May 10 '11 at 15:10

jsherer

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Executing slot on every application's event loop iteration

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