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Hi! I'm creating a simple app in QT 4.7. I have a dialog with a pushbutton and a lcdnumber to display the result from the operation done when i click in the button. This operation can be very expensive and take many time, so i used QApplication::processevents() to avoid that the application become blocked during the process.

But if an user press the pushbutton any time more after to push it before, QApplication::processevents() stop the first execution and run a new thread. Finally, when the execution finished, the second result appears in the lcdnumber and in a few milisec appears the first one (from the first execution). I want only the second result appears in the lcdnumber and if the pushbutton is clicked any time before, the first process will terminate inmediatly. I write some code that works well with a global var, but I think maybe is possibly to do it in a smart way (with eventfilter or reimplement the function event), but i'm not sure how and the examples i don't give me a solution. Plase anybody knows how it would be done without global vars? If i do an event filter function is necesary to installeventfilter? Thanks a lot and regards

//global var stop
bool stop=false;

void conditionDialog::on_aplicarButton_clicked()
{
stop=true;

for (int i=0; i<(int)quini.size(); i++) {
ui->progressBar_calculo->setValue((i+1)*100/quini.size());
if (QApplication::hasPendingEvents()) {
QApplication::processEvents();
if (!stop) return;
}
//do it some heavy work
}
stop=false;

Sorry, maybe I'm wrong and is not a new thread. The execution of the first call is paused and start a second when the user push the button anytime, and when the second execution finishes, the first continues at the point after the processevent() call. I don't want to disable/enable the button during this process cause it can take many time. Another idea? Thanks a lot