I was trying to create a simple console application to try out Qt's XML parser. I started a project in VS2008 and got this template:
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
return a.exec();
}
Since I don't need event processing, I was wondering whether I may get into trouble if I neglect to create a QCoreApplication and running the event loop. The docs state that it's recommended in most cases.
For the sake of curiosity however, I am wondering how could I make some generic task execute on the event loop and then terminate the application. I was unable to google a relevant example.
Had the same problem. found some videos on Youtube. So here is an even simpler suggestion. This is all the code you need:
#include <QDebug>
int main(int argc, char *argv[])
{
qDebug() <<"Hello World"<< endl;
return 0;
}
The above code comes from Qt5 Tutorial: Building a simple Console application by
Dominique Thiebaut
You don't need the QCoreApplication
at all, just include your Qt objects as you would other objects, for example:
#include <QtCore>
int main()
{
QVector<int> a; // Qt object
for (int i=0; i<10; i++)
{
a.append(i);
}
/* manipulate a here */
return 0;
}
You can call QCoreApplication::exit(0) to exit with code 0
I managed to create a simple console "hello world" with QT Creator
used creator 2.4.1 and QT 4.8.0 on windows 7
two ways to do this
Plain C++
do the following
or
QT Console
example: for QT console "hello world"
file - new file project 'project name '
other projects - QT Console Application
Targets select 'Desktop'
project management - next
code:
#include <QtCore/QCoreApplication>
#include <iostream>
using namespace std;
int main(int argc, char *argv[])
{
QCoreApplication a(argc, argv);
cout<<" hello world";
return a.exec();
}
ctrl -R to run
compilers used for above MSVC 2010 (QT SDK) , and minGW(QT SDK)
hope this helps someone
As I have just started to use QT recently and also searched the Www for info and examples to get started with simple examples still searching...
Don't forget to add the
CONFIG += console
flag in the qmake .pro file.
For the rest is just using some of Qt classes. One way I use it is to spawn processes cross-platform.
You could fire an event into the quit() slot of your application even without connect(). This way, the event-loop does at least one turn and should process the events within your main()-logic:
#include <QCoreApplication>
#include <QTimer>
int main(int argc, char *argv[])
{
QCoreApplication app( argc, argv );
// do your thing, once
QTimer::singleShot( 0, &app, &QCoreApplication::quit );
return app.exec();
}
Don't forget to place CONFIG += console
in your .pro-file, or set consoleApplication: true
in your .qbs Project.CppApplication.
Source: Stackoverflow.com