QTimer / QThread question

[Galen]

I have an application that sorts arrays of ints (6 at a time). There is a main QWidget that has 6 subclassed QWidgets that handle the drawing of the sort progress. There is also another thread that handles all the signals from buttons and sliders. This one creates the 6 sort threads and also a "ThreadWatcher" thread. This last one calls update() for the corrosponding QWidget while the sort threads are alive and updates QLabels after the sort threads exit. Originally I just had a loop that checked each one and called update() and then slept for 10ms (which worked), but I decided to try to do it all with slots.

The code below gives the following errors:

"QObject: Cannot create children for a parent that is in a different thread. (Parent is ThreadWatcher2(0x221b888), parent's thread is QThread(0x3f4ae0), current thread is ThreadWatcher2(0x221b888)" -- on start but this still works fine.

"QObject::killlTimer: timers cannot be stopped from another thread" -- when I try to pause, this doesn't work.

Attempting to kill (setting control[1]) doesn't work (here, on the loop-based method it did), but I can probably figure that one out.

I'll leave out everything before run(), so here's the revelant variables. I also left out the other 5 finished() handlers. If there's some way to create a single handler with an (int) to differentiate which I'd be interested in that as well, as they are all identical except the array index. I'm guessing QOBject::moveToThread() is the solution (if there is one) but I'm unclear on the specifics. updateTimer->moveToThread(this) after allocation in run() doesn't seem to help.

alive[6] = bool array, marked to false in finished() handler for each thread
window[6] = references to the QWidgets to call update() on
thread[6] = array of sort thread references
control[2] = volatile bool array, [0] for pause and [1] for kill, set in (ommitted) parent thread
threadsLeft = starts a 6, decremented in each finished() handler
lock / condition = QMutex / QWaitCondition set by parent to pause

void ThreadWatcher2::run() {
    updateTimer = new QTimer(this);
    connect(updateTimer, SIGNAL(timeout()), this, SLOT(timeoutHandler()));
    connect(thread[0], SIGNAL(finished()), this, SLOT(finishedHandler0()));
    connect(thread[1], SIGNAL(finished()), this, SLOT(finishedHandler1()));
    connect(thread[2], SIGNAL(finished()), this, SLOT(finishedHandler2()));
    connect(thread[3], SIGNAL(finished()), this, SLOT(finishedHandler3()));
    connect(thread[4], SIGNAL(finished()), this, SLOT(finishedHandler4()));
    connect(thread[5], SIGNAL(finished()), this, SLOT(finishedHandler5()));
    updateTimer->start(delay);
 
    QThread::exec();
    status->setText("Status: Done");
}
void ThreadWatcher2::timeoutHandler() {
    for (int i=0; i<6; i++) {
        if (alive[i])  
             window[i]->update(); }
 
    if (threadsLeft==0) {
         QThread::exit(0); }
 
    if (control[1]) 							
         QThread::exit(1); 
     else if (control[0]) {
         updateTimer->stop();
         lock->lock();
         condition->wait(lock); 
         lock->unlock();
         updateTimer->start(delay);}
}
void ThreadWatcher2::finishedHandler0() {
    disconnect(SIGNAL(finished()), this, SLOT(finishedHandler0()));
    alive[0] = false;								
    threadsLeft--;
    seconds[0] = (float)runTime[0] / 1000.0f; 
    time[0]->setText("Time: "+QString::number(seconds[0],'g',3));  
}
void ThreadWatcher2::finishedHandler1() {
.
.
.

void ThreadWatcher2::run() {
    updateTimer = new QTimer(this);
    connect(updateTimer, SIGNAL(timeout()), this, SLOT(timeoutHandler()));
    connect(thread[0], SIGNAL(finished()), this, SLOT(finishedHandler0()));
    connect(thread[1], SIGNAL(finished()), this, SLOT(finishedHandler1()));
    connect(thread[2], SIGNAL(finished()), this, SLOT(finishedHandler2()));
    connect(thread[3], SIGNAL(finished()), this, SLOT(finishedHandler3()));
    connect(thread[4], SIGNAL(finished()), this, SLOT(finishedHandler4()));
    connect(thread[5], SIGNAL(finished()), this, SLOT(finishedHandler5()));
    updateTimer->start(delay);

    QThread::exec();
    status->setText("Status: Done");
}
void ThreadWatcher2::timeoutHandler() {
    for (int i=0; i<6; i++) {
        if (alive[i])  
             window[i]->update(); }

    if (threadsLeft==0) {
         QThread::exit(0); }

    if (control[1]) 							
         QThread::exit(1); 
     else if (control[0]) {
         updateTimer->stop();
         lock->lock();
         condition->wait(lock); 
         lock->unlock();
         updateTimer->start(delay);}
}
void ThreadWatcher2::finishedHandler0() {
    disconnect(SIGNAL(finished()), this, SLOT(finishedHandler0()));
    alive[0] = false;								
    threadsLeft--;
    seconds[0] = (float)runTime[0] / 1000.0f; 
    time[0]->setText("Time: "+QString::number(seconds[0],'g',3));  
}
void ThreadWatcher2::finishedHandler1() {
.
.
.

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thanks