I would simply make sure that you don’t emit your signal if it should not emit. Best place to stop such an overflow it as the source…

Is there some way for your process to know if the result is new or updated or something like that? If not, you could use a technique like this [developer.qt.nokia.com] to throttle your signal emissions, I guess.

Andre wrote:

I would simply make sure that you don’t emit your signal if it should not emit.

maybe this?

I don’t get it. With your finished boolean you just turn someLongProcessing() into a blocking call. But it is already blocking.

Sorry forgot the stop = true; line.

This will break the loop. I don’t want to break the loop when someLongProcessing() returns true. You obviously did not understood my problem.

It is generally only useful to update a text if it has actually changed, so assuming that some successive calls may produce the same text result:

I’m sorry but successive calls wont produce the same result.
There’s nothing to do with the event queue?

QApplication::processEvents() helps?

Hi neFast,

is this loop executed in a thread?
If yes, processEvents will never help.

Yes it is in a thread. What do you suggest?

From that thread you have no influence on the main thread directly by calling processEvents etc. If you fill up the queue of one thread by another one, you have to think, whether it is the correct way for doing so.

Perhaps you should change the logic to something like this:

thread —> setText on intermediatObject —> emit signal

intermediatObject is a thread save object, which stores the last text and stores, whether the text was already read. If a text is set, it emits the signal, if after the last read there came no new text.

But that changes the logic completely…

Another consideration is that the text might change quickly enough for the user not even to notice it. It would probably make sense to not let the longProcessThingy() control the text the user sees unless there’s an error of sorts. The current approach seems indeed too naive for successful operation.

Sorry to bump this thread, but are there any best practice that I could find to solve my problem?

• EDIT: I just found about Qt::BlockingQueuedConnection, could this be a good idea?

If your thread can wait, sure, try that.