Busy Cursor in window started by QProcess

SamurayH

Hi,
I'm wondering what could make the cursor of a widget busy for while, if it started using QProcess. For example, let's say that I have a showWidget.exe executable that shows a simple widget like this:

#include <QApplication>
#include <QtWidgets/QWidget>

int main(int argc, char *argv[])
{
   QApplication a(argc, argv);

   QWidget w;
   w.show();

   return a.exec();
}

And in an other process I do :

 QProcess p;
 p.start(".../showWidget.exe"); 
 p.waitForFinished(-1);

The shown widget gets a busy cursor for a while. That's it.
It's not a big issue, but I just want to know if that can be fixed, because if I use the CreateProcess and WaitForSingleObject, win apis, there's no busy cursor.
Thanks for your help.

SGaist

Hi,

What do you mean by "in another process" ?

SamurayH

I mean from an other program. I'm not running that code in showWidget.exe.

aha_1980

@SamurayH

p.waitForFinished(-1); should only be used in threads. connect a slot to the finished() signal if you don't use threads instead.

SamurayH

Solved.
I didn't know about this. The first time I checked the docs about waitForFinished, it says :
"This function can operate without an event loop. It is useful when writing non-GUI applications and when performing I/O operations in a non-GUI thread."
And then I used to do like this :

int main(int argc, char *argv[])
{
    QProcess p;
    p.start(".../showWidget.exe"); 
    p.waitForFinished(-1);
    
   if(p.exitCode() != ...)
//...

  return 0;
}

Thank you very much @aha_1980.