Question

I’m making the transition from Eclipse CDT (with Qt integration plugin) to QtCreator 2.0 but there is still one thing that bother me with QtCreator :

When I debug in QtCreator, I don’t see my qDebug messages inside the Application output tab until I stop the application I’m debugging… Then they are all displayed at once which is not very useful.

With Eclipse, I don’t have this problem : the qDebug messages are displayed correctly when encountered while stepping through the source code.

I’m using both Eclipse CDT and Qt Creator under Windows. I didn’t try under Linux (which is not an option right now).

Answer 1

While not a complete answer, you can install DebugView (If you’re on an XP machine) to view the qDebug output while you try to figure this out.

Another solution might be considered a hack, but works quite nicely, is to simply hijack debug messages yourself:

#include <QtCore/QCoreApplication>
#include <QDebug>
#include <iostream>

void msgHandler( QtMsgType type, const char* msg )
{
    const char symbols[] = { 'I', 'E', '!', 'X' };
    QString output = QString("[%1] %2").arg( symbols[type] ).arg( msg );
    std::cerr << output.toStdString() << std::endl;
    if( type == QtFatalMsg ) abort();
}

int main(int argc, char *argv[])
{
    qInstallMsgHandler( msgHandler );
    QCoreApplication a(argc, argv);

    qDebug() << "Hello world.";
    qWarning() << "Uh, oh...";
    qCritical() << "Oh, noes!";
    qFatal( "AAAAAAAAAH!" );

    return a.exec();
}

Which would output:

[I] Hello world. 
[E] Uh, oh... 
[!] Oh, noes! 
[X] AAAAAAAAAH!

This application has requested the Runtime to terminate it in an unusual way.
Please contact the application's support team for more information.

This is actually a modification of some code that I use myself to send qDebug, qWarning, etc., to a log file.