ProcessEvents CPU Using

[umtkyck]

Hi,

Using QApplication::processEvents() in console applications uses lots of CPU , is there an other way to use handle timer isActive state? When I delete processEvents() routine it doesnt goes out from the loop.

@
timer_responseControl.setSingleShot(true);
timer_responseControl.start(1000);
while(timer_responseControl.isActive()){
if(baudratedetectioncame){
timer_responseControl.stop();
baudratedetectionIsOk=1;
}
QApplication::processEvents();
}
@

[dheerendra]

CPU utilisation may be coming from while loop rather than ProcessEvents. Did you try commenting the processEvents and checked CPU utilisation. Why do you want while loop here ?

[umtkyck]

I solved problem with QEventLoop:
just connect the packetcame signal to q quit slot.

QEventloop q;
timer_responseControl.setSingleShot(true);
timer_responseControl.start(1000);
q.exec();
if(timer_responseControl.isActive()){
    if(rfresetcame){
        timer_responseControl.stop();
        rfresetIsOk=1;
        q.quit();
    }
}

[dheerendra]

Another way you can look at is use two timers one with zero timer. Something like follows.

@Widget::Widget(QWidget *parent)
: QWidget(parent)
{
timer = new QTimer;
timer->setInterval(1000);
timer->setSingleShot(true);
timer->start();
connect(timer,SIGNAL(timeout()),this,SLOT(callme()));

timer2 = new QTimer;
timer2->setInterval(0);
timer2->start();
connect(timer2,SIGNAL(timeout()),this,SLOT(callme2()));

}

void Widget::callme() {
qDebug() << " Call me" <<endl;
timer->stop();
}

void Widget::callme2() {
qDebug() << " Call me-2" <<endl;

if (timer->isActive()){
    qDebug() << "Timer is still active" <<endl;
}else {
    qDebug() << "Timer not active now" << endl;
}

}
@