Infinite condition checking

[SGaist]

Hi,

Since foo checks the condition on each call, in fact, you want something that calls regularly foo ?

[hbatalha]

@SGaist something that calls condition regularly and if condition returns true then foo will be called

[SGaist]

Sounds like a simple QTimer that calls foo regularly should do the job.

[hbatalha]

@SGaist That did solve my problem, thanks

void SomeClass::foo()
{
    if( ! condition)
    {
        QTimer::singleShot(5000, this, &SomeClass::foo);

        return;
    }
...

}

[SGaist]

You might want to consider making a QTimer member variable to be able to stop it for example when your application ends.

[hbatalha]

@SGaist didn't quite understand what you meant, when my application won't everything be stopped?

Also, I need to call foo only once when the timeout is emitted, took that example from the documentation.

[SGaist]

I don't know how long foo will take so you might not want for it to triggered when you end your application. Ending an application does not mean everything is destroyed instantly.

[hbatalha]

@SGaist foo is not from the mainwindow, is part of another class, should I call stop in the destructor?

[jsulm]

@hbatalha said in Infinite condition checking:

is part of another class

Then put it there as member variable and stop it in destructor (or whenever needed).

[hbatalha]

@jsulm ok thanks

[hbatalha]

@SGaist @jsulm

Ending an application does not mean everything is destroyed instantly.

I have followed your suggestion, and now I am wondering, is this something that I have to always watch out for, is there a name for this kind of situation, a reference I can search?

And also, why is everything not destroyed instantly? What are the steps being taken? What is happening under the hood there? Any reference?

[SGaist]

Order of destruction, code run during destruction, etc

Think of a database, you likely appreciate the fact that all operations are finalised before it stops so you don't have corrupted data when you restart it.