[Interest] QObject::connect returns true, but the, connection does not work

[Roland Hughes]

Stupid question, but is this a console app?

I'm asking because this happens with console apps. It can happen with 
any app, but console apps tend to have the problem most often. Here is 
what I mean:

#include <QCoreApplication>
#include <QDebug>
#include <QTimer>

#include "consoleinput.h"

int main(int argc, char *argv[])
{
     QCoreApplication a(argc, argv);
     ConsoleInput console;
     bool b = a.connect(&console, &ConsoleInput::quit, &a, &QCoreApplication::quit);
     qDebug() << "result of connect " << b;

     QTimer::singleShot(0, &console, &ConsoleInput::run);

     return a.exec();

}

If you do not use a QTimer to launch the console input method so it runs 
from within the exec() loop, i.e. replace the QTimer line with

console.run();

Your connect call will return true but the signal will never trigger the 
slot because execution is occurring outside of an event loop.

-- 

Roland Hughes, President
Logikal Solutions

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