Problems using qwt

[Guddleif]

Hello. I am trying to make a program showing a simple compass in Qt. I installed qwt 6.0.0 successfully (i think. did make and make install without any errors).

Now I started a new qt GUI project in qt creator. I added the following lines to the *.pro file:
INCLUDEPATH += C:\qwt-6.0.0\src
LIBS += -L"./libs" \
C:\qwt-6.0.0\lib\libqwt.a \
C:\qwt-6.0.0\lib\libqwtmathml.a

I then added #include <qwt_compass.h> to mainwindow.h
In the mainwindow constructor i added a compass:

QwtCompass *compass;
compass = new QwtCompass(this);

The program compiles fine (i use the release build), but it will not run. If i remove the "new compass"-line it runs just fine. Anyone knows what I did wrong?

Really appreciate any help!

[Uwe]

I added the following lines to the *.pro file: ...

Configure qmake so that it is aware of the Qwt feature files ( read the INSTALL file once more ) and then replace all what you have added to your project file by:

CONFIG += qwt

CONFIG += qwt

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Uwe

[Guddleif]

Thanks for the fast reply Uwe.

I copied the qwt.prf into C:\Qt\2010.05\qt\mkspecs\features\win32 and added CONFIG += qwt to my project file.

Now when I try to compile it does not find the qwt-header-files. How do i configure qmake?

[Uwe]

What is so difficult about doing what is written in the INSTALL advices ?

Don't copy files around ( your copying was incomplete ) - instead configure qmake to check the directory, where make install has installed the features files.

Uwe

[Guddleif]

Well, i still dont know how to configure qmake.

The reason i copied the file is that your INSTALL advices redirected me to http://doc.qt.nokia.com/4.7/qmake-ad...ation-features where it said that qmake automatically checks the features\win32-folder.

If you could tell me how to configure qmake to check the qwt folder, that would be of great help.

Thanks again for helping me out.

[Uwe]

The reason i copied the file is that your INSTALL advices redirected me to http://doc.qt.nokia.com/4.7/qmake-ad...ation-features where it said that qmake automatically checks the features\win32-folder.

This page explicitely documents how to configure qmake to look for features files. What else are you asking for ?

I'm using #2 setting QMAKEFEATURES as a property ( qmake -set QMAKEFEATURES ... ) but this one is not better or worse than the other solutions.

The problem with copying qwt.prf is, that it includes qwtconfig.pri that you didn't copy. But beside this: don't copy files around as long as you don't know what you are doing + don't mix up Qt and Qwt installations. Even if you believe this is easier - it isn't.

Uwe

[Guddleif]

Sorry for acting like an idiot, but I probably just lack some basic knowledge about variables.

If I want to use #2, like you did, how do I change the QMAKEFEATURES property variable? And where do I find it? From you answer above I guess I have to open a command window, go to a certain directory and then write "qmake -set QMAKEFEATURES ...something". Hope my ignorance doesn't make you too frustrated

[Uwe]

I guess I have to open a command window, ...

Yes.

...go to a certain directory

No ( when qmake can be found using the PATH environment variable ).

...then write "qmake -set QMAKEFEATURES ...something".

Yes, where "something" is the path, where you have installed the features file.

On my Linux box it is "/usr/local/qwt-6.0.0/features" on you box it depends on the path you have configured in qwtconfig.pri - maybe: "C:/Qwt-6.0.0/features".

Uwe

[Guddleif]

Okay. I added the path to QMAKEFEATURES. When I now type "qmake -query QMAKEFEATURES" the output is : "C:\qwt-6.0.0\features" which is the right directory. So I guess it has been added to the variable correctly.

I started a new project in Qt and added "CONFIG += qwt" to the .pro-file. I then added "#include <qwt_compass.h>" to mainwindow.h. When I try to compile I still get the error "qwt_compass.h: no such file or directory".

Any idea?

[Guddleif]

Little update. If I set "qmake -set QMAKEFEATURES C:\qwt-6.0.0" instead of C:\qwt-6.0.0\features I can compile again without errors. However, as soon as I try to use qwt in my program it crashes. So I'm kinda back to square one...

[Guddleif]

New update. I think I might have found the cause of the problems. I deleted qwt and unzipped the latest version (6.0.0) again. when I go to the folder and type mingw32-make it starts compiling, but after a while the following error appears:

.
.
.
compiling qwt_slider.cpp
compiling qwt_thermo.cpp
compiling qwt_wheel.cpp
moc qwt_dyngrid_layout.h
/usr/bin/sh: C:/Qt/2010.05/qt/bin/moc.exe: Invalid argument
mingw32-make[2]: *** [moc/moc_qwt_dyngrid_layout.cpp] Error 126
mingw32-make[2]: Leaving directory `c:/Qt/2010.05/qt/qwt-6.0.0/src'
mingw32-make[1]: *** [debug-all] Error 2
mingw32-make[1]: Leaving directory `c:/Qt/2010.05/qt/qwt-6.0.0/src'
mingw32-make: *** [sub-src-make_default-ordered] Error 2

Does anyone know what to do?