Show progress of a time consuming operation

Hi,

i am writing a program which calculates the irradiation dose for cancer treatment. This can take some time, so my idea was, to show up a simple dialog with a progress-bar in it. I dont know really how to do it because when the dialog is started, the program stops as long it is opened.

I like to implement such an interface:

Code:

---

class ProgressDialog : public QWidget {
public:
   signalProgress(); //the bar should move a bit to right
   setTotalProgress(int); //maxValue of progress bar
}

---

My programm is a console program actually. I dont want to do all the calulation stuff in a window. So - how should i implement the main() function. My idea was like following, but this won't work:

Code:

---

void doComplicatedStuff(ProgressDialog& pd){
   while(calculating){
      someCalculation;
      pd.signalProgress();
   }
}
 
main(argc,argv){
    QApplication a(argc,argv);
    ProgressDialog pd;
    pd.show();
    doComplicatedStuff(pd);//no dialog visible
    return a.exec(); //here, the dialog pops up - swapping last lines is no solution
}

---

So what can i do instead? I hope, you can help me.
Thanks! Thanks! Thanks! ;)

Cheers

Hi, you might want to take a look at QProgressDialog. :)

And QCoreApplication::processEvents.

Thanks for your reply! I have found QProgressDialog already but it doesnt solve my problem, that the application is unresponsible.
What can I do with QCoreApplication::processEvents? I am really a newbie in qt programming.
I tried to do it with seperate threads - the main thread for the dialog, an extra thread for the calculation - but there the problem is, that you can't connect signal and slots from different threads (runtime exception).

With processEvents() you can.... process pending events thus making your application responsive.

I think I have to do more reading about this stuff. Thank you!

Okay... i read a bit about it. How should be now the semantic of the main function

like this?:

Code:

---

int main(argc,argv){
   QApplication app(argc,argv);
   QProgressDialog pd();
   pd.setrange(0,100);
 
   //now the calculation loop?
   for(int i = 0; i < 100, ++i){
      someCalculation;
      pd.setValue(i);
      app.processEvents();
   }
   return app.exec();
}

---

Is this right? I dont know really, where to place the app.exec - why i need it.
Is this the right order, or should the app.exec() be placed over the calculation loop?

You don't have to enter to the event loop of the application at all if showing a progress bar is all what your application does...