Detecting whether a singleshot QTimer is currently being run

Dummie1138

Hi. I have a function that starts a singleshot QTimer for 5 seconds. During those 5 seconds, there are a series of functions that I want to behave differently.

The way I have it executed right now is like so:

bool isSingleShotActive;
void functionName(){
   //Some other function processes

        QTimer::singleShot(5000, this, SLOT(otherFunctionName())); //triggers the determineStability function after 5 seconds.
        isSingleShotActive = true;
}

void otherFunctionName(){
   //Some other function processes
        isSingleShotActive = false;
}

void evenOtherFunctionName(){
   if (isSingleShotActive == false)
     do_the_special_thing;
    else
      do_the_default_thing;
}

I was wondering whether there is a signal I can use on the oneshot to indicate that the oneshot is active.

JonB

@Dummie1138
static QTimer::singleShot() is really just a "convenience" function. It simply creates/uses a QTimer instance of its own, which you cannot see/access.

Yes, the code you show is indeed the correct/corresponding way to create your own QTimer instance and set it to single-shot mode. If you want to access that QTimer variable from elsewhere you will need to e.g. make it a class member variable, and an accessor method if you want it accessible outside the class.

mchinand

You could create your instance of QTimer on the heap and then use QTimer::isActive() in your other method.

Dummie1138

@mchinand Are you suggesting building a QTimer and changing singleShot to true instead of using QTimer::singleShot? My understanding of QTimer::singleShot is that it's just a function and not a QTimer object, is that correct?

Something like this:

    QTimer *timer = new QTimer(this);
    timer->setSingleShot(true);
    connect(timer, &QTimer::timeout, this, SLOT(otherFunctionName()));
    timer->start(5000);

In that case will I have to declare QTimer *timer outside of the function, given that I need it's existence to be detected by another function?

JonB

@Dummie1138
static QTimer::singleShot() is really just a "convenience" function. It simply creates/uses a QTimer instance of its own, which you cannot see/access.

Yes, the code you show is indeed the correct/corresponding way to create your own QTimer instance and set it to single-shot mode. If you want to access that QTimer variable from elsewhere you will need to e.g. make it a class member variable, and an accessor method if you want it accessible outside the class.