[Solved] QMessageLogContext does not name a type with Qt SDK 5.0.2 - Ubuntu

code_fodder

Hi Guys,

Sorry for the long post, I think the question is relatively simple, but I feel the need to explain the situation I got myself into, however you can probably jump straight to the "Questions" section at the end :) ...

I have been using Qt SDK 5.0.2 on Windows and Linux with much success :)

However, I am now expanding my operation and trying to make a sound build environment and a repeatable process to make it. I have almost got there but I have a couple of little niggles left.

Problem Description
Using virtual box to keep testing my installations I am creating systems with Ubuntu 12.04 + all updates. This was my process:

install QtCreator from the Ubuntu software centre (this was a mistake I think)
Uninstall Qt Creator from the Ubuntu software centre.
Download Qt SDK 5.0.2 from "qt-project.org/downloads", then cd to the download directory and do:
@sudo chmod +x qt-linux-opensource-5.0.2-x86-offline.run
sudo ./qt-linux-opensource-5.0.2-x86-offline.run@

Other then installing Qt Creator and un-installing it, everything is the same as my working Linux version (on real PC, i.e. non-Virtual box)

But I get the following issue:
@main.cpp:60:45: error: 'QMessageLogContext' does not name a type
main.cpp:60:65: error: ISO C++ forbids declaration of 'context' with no type [-fpermissive]
main.cpp: In function 'void qDebugMsgHandler(QtMsgType, const int&, const QString&)':@

Here is my code (which works very well on my Qt 5.0.2 on windows and my other linux installation:
@// Message handler for qDebug(), qWarning(), qCritical(), qFatal().
// Note: For qDebug() there are no automatic end-of-lines for maximum
// flexibility this means that you need to put a "\n" or << endl; at
// the end of your message.

void qDebugMsgHandler(QtMsgType type, const QMessageLogContext &context, const QString &msg)
{
QByteArray localMsg = msg.toLocal8Bit();
switch (type) {
case QtDebugMsg:
myprintf(OUT_ALL, "%s", localMsg.constData());
break;
case QtWarningMsg:
myprintf(OUT_ALL, "\nWarning: %s \t%s (line %u) in %s\n\n", localMsg.constData(), context.file, context.line, context.function);
break;
case QtCriticalMsg:
myprintf(OUT_ALL, "\nCritical: %s \t%s (line %u) in %s\n\n", localMsg.constData(), context.file, context.line, context.function);
break;
case QtFatalMsg:
myprintf(OUT_ALL, "\nFatal: %s \t%s (line %u) in %s\n\n", localMsg.constData(), context.file, context.line, context.function);
abort();
}
}@

Questions

QMessageLogContext is a Qt 5 addition. It looks like I don't have that library. When I add the line '#include <QMessageLogContext>', the tool tip even says "can't find file". So how do I install this library?
Also my include paths during the build are suspect, for example:
@g++ -c -pipe -Wall -O2 -Wall -W -D_REENTRANT -DQT_WEBKIT -DQT_NO_DEBUG -DQT_XML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED -I/usr/share/qt4/mkspecs/linux-g++ -I. -I/usr/include/qt4/QtCore -I/usr/include/qt4/QtNetwork -I/usr/include/qt4/QtXml -I/usr/include/qt4 -Icommsnet -Icommsnet/device -Icommsnet/vocoder -Iconfig -Iif -Irpe -Irtp -ItacChat -Iutils -I../_out -o ../_out/main.o main.cpp@
You can see there are not Qt5 paths whereas on my other linux build there are many more paths like "usr/share/Qt5.0.2/5.0.2/gcc/include/QtCore, etc.... does this mean that I don't have Qt 5 properly installed?
What can I do about this to update it?

I have the feeling when I installed Qt Creator on its own I screwed up :( , but I am not sure if that is the issue or not

EDIT: forgot to add: When I remove this code (i.e. comment it out) my project builds and runs great :). I figure that most of the stuff I use is pre Qt5 stuff .. so at least I have some sort of working version of Qt :o

Max Krause

[deleted]

SGaist

Hi,

It seems you are using a Qt 4 qmake which probably is the one installed with your system's Qt development package.

Did you take a look into your QtCreator Qt versions ?

code_fodder

This is from the "about" in my Qt Creator GUI:

@Qt Creator 2.7.0
Based on Qt 5.0.2 (32 bit)

Built on Apr 9 2013 at 09:31:06

From revision b6257ef735

The program is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.@

Is that what you mean?
Is there another place I can see the versions?

SGaist

No it's not, the version of Qt used to build QtCreator and the one you use to build your application are not related.

Go to Options/Preferences -> Build & Run -> Qt Versions

code_fodder

Ahh.... I see... this makes sense now!, here is what it says:

Auto Detect:
Qt 5.0.2 GCC 32bit /opt/Qt5.0.2/5.0.2/gcc/bin/qmake

Manual:
Qt 4.8.1 in PATH (System) /usr/bin/qmake-qt4

I think you are right, so what do I need to change to make that Qt5?, just point it to the Qt5 path? (where would that be?)

code_fodder

But... I just looked at my working Linux and that is exactly the same :(, except it has a different "manual" version 4.6.2...

SGaist

Go in the Kits tab and either add a new kit using your Qt 5 or change the current kit to use your Qt 5

code_fodder

Right... so, I have no idea exactly what happened, but this has fixed my issue! :)

What I did was:
Attempted to "Add..." and kit in the build and run menu. Saw loads of options that I did not understand. Then cancelled it. Went back in and saw a new "Desktop" entry under "Manual:". I clicked on new entry again, click auto-detect a few times... Then finally I deleted my new entry.

After that I could not build my project (option was greyed out).

Then I closed and opened Qt Creator and tried again, it came up with the "you need to configure your project" page (like when you get the project with no .pro.user file). I had two options, I check the one that had 5.0.2 in it and un-checked the other.

Then... it all just works! - I have the same kits and versions in my build & run options...
I guess this allowed Qt to update itself or something?

Anyway, here is my build output:
@g++ -c -pipe -Wall -g -Wall -W -D_REENTRANT -fPIE -DQT_QML_DEBUG -DQT_DECLARATIVE_DEBUG -DQT_XML_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -I/opt/Qt5.0.2/5.0.2/gcc/mkspecs/linux-g++ -I. -Icommsnet -Icommsnet/device -Icommsnet/vocoder -Iconfig -Iif -Irpe -Irtp -ItacChat -Iutils -I/opt/Qt5.0.2/5.0.2/gcc/include -I/opt/Qt5.0.2/5.0.2/gcc/include/QtXml -I/opt/Qt5.0.2/5.0.2/gcc/include/QtNetwork -I/opt/Qt5.0.2/5.0.2/gcc/include/QtCore -I../_out -o ../_out/main.o main.cpp
@

Thanks very much for your help SGaist :)

SGaist

Great !

You're welcome !

Don't forget to update the thread's title to solved so other forum users may know that a solution has been found :)

code_fodder

Ahhh.... I never knew how that happened!, I thought it was an admin guy doing that :o

I will update it now.
Thanks