Qt timers cannot be stopped from another thread

Use QTimer for this purpose and make use of SIGNALS and SLOT for the purpose of starting and stopping the timer/s from different threads. You can emit the signal from any thread and catch it in the thread which created the timer to act on it.

Since you say you are new to Qt, I suggest you go through some tutorials before proceeding so that you will know what Qt has to offer and don't end up trying to reinvent the wheel. :)

VoidRealms is a good starting point.

You have this problem because the timers in the static array is created in Thread X, but started and stopped in Thread Y. This is not allowed, because Qt rely on thread affinity to timeout timers.

You can either create, start stop in the same thread or use signal and slots to trigger start and stop operations for timers. The signal and slot solution is a bit problematic Because you have n QTimer objects (Hint: how do you start the timer at position i?)

What you can do instead is create and initialize the timer at position tmrnbr in

TimerForFWUpgrade::set(unsigned char tmrnbr, unsigned int time){     singleTimer[tmrnbr] = new SingleTimer(0);     singleTimer[tmrnbr]->set(time);}

which is executed by the same thread.

Futhermore, you don't need a SingleTimer class. You are using Qt5, and you already have all you need at your disposal:

• SingleTimer::isElapsed is really QTimer::remainingTime() == 0;
• SingleTimer::set is really QTimer::setSingleShot(true); QTimer::start(time);
• SingleTimer::slot_setElapsed becomes useless
• ThusSingleTimer::SingleTimer becomes useless and you dont need a SingleTimer class anymore

I got the errors away after changing my timer concept. I'dont use anymore my SingleTimer module. Before the QTimer I won't let timeout and maybe because of that I run into problems. Now I have a cyclic QTimer that times out every 100ms in slot function I will then count the events. Below my working code:

TimerForFWUpgrade::TimerForFWUpgrade(QObject* parent) : QObject(parent),                                                        pTime(new QTimer(this)){    connect(pTime, SIGNAL(timeout()), this, SLOT(slot_handleTimer()));    pTime->setTimerType(Qt::PreciseTimer);    pTime->start(100);}void TimerForFWUpgrade::set(unsigned char tmrnbr, unsigned int time){    if(tmrnbr < NR_OF_TIMERS)    {        if(timeBase != 0)        {            myTimeout[tmrnbr] = time / timeBase;        }        else        {            myTimeout[tmrnbr] = 0;        }        myTimer[tmrnbr] = 0;        myElapsed[tmrnbr] = false;        myActive[tmrnbr] = true;    }}char TimerForFWUpgrade::isElapsed(unsigned char tmrnbr){    QCoreApplication::processEvents();    if(tmrnbr < NR_OF_TIMERS)    {        if(true == myElapsed[tmrnbr])        {            return 1;        }        else        {            return 0;        }    }    else    {        return 0; // NOK    }}void TimerForFWUpgrade::slot_handleTimer(){    for(UINT8 i = 0; i < NR_OF_TIMERS; i++)    {        if(myActive[i] == true)        {            myTimer[i]++;            if(myTimeout[i] < myTimer[i])            {                myTimer[i] = 0;                myElapsed[i] = true;                myActive[i] = false;            }         }    }}