Undefined Reference QwtPlot::QwtPlot(QWidget*)

Hi,

I am using Ubuntu 9.04 with the qt4, qt creator and installed qwt using the synaptic manager. Looked like everything worked fine for me. The Designer has the new plugins.

Started a new project and added a plot widget to a dialog, but when I am trying to compile it fails because it cannot include #include "qwt_plot.h"

I know how to add new include paths in visual studio but I have no idea how to do that in QTCreator or does somethin different went wrong ?

Thanks in advance for your help :)

kind regards


loco

EDIT:
Ok this is what I did:

copying the *.h files in src/ to /usr/local/include/:

Code:

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# cp src/*.h /usr/local/include

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copying those in lib/ to /usr/local/lib/.

Code:

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cd lib && tar -cf l.tar *
 # 
 # mv l.tar /usr/local/lib
 # cd /usr/local/lib
 # tar xf l.tar
 # rm l.tar

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running ldconfig:

Code:

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#ldconfig

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No more include error but another one appears:

Code:

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"undefined reference QwtPlot::QwtPlot(QWidget*)"

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Any suggestions ? Sounds like the libs are missing :(

Take a look at the examples shipped with Qwt (specifically their .pro files). You need to link to the Qwt library.

Can't compile samples with the QT Creator. I am getting a lot of

Code:

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undefined reference: QwtScaleMap::QwtScaleMap()

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Somethin' gone wrong. Any great installations guides ? Found nothin' helpful for now. :(

Thanks

Ok finally i managed to install Qwt on Ubuntu 9.04 and run the examples. It is really simple once you figured out how to install the whole thing. I will post it my step by step guide :)


1. Go to http://sourceforge.net/projects/qwt and download the tar.gz file
2. Extract the package into your home folder \home\YOU\Qwt-5.2.0
3. Open the Terminal and change into the Qwt directory

Code:

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cd 'home\YOU\Qwt-5.2.0'

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Then

Code:

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qmake

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Code:

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sudo make

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Code:

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sudo make install

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Okay. Now we have to link the shared libraries. Go to the following folder
\etc\ld.so.conf.d and open the file libc.conf

Something like

Code:

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# libc default configuration
/usr/local/lib

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should be in there. Add the line

Code:

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/usr/local/qwt-5.2.0/lib

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Save and close the file. Now lets go back to the terminal.
Simply enter

Code:

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sudo ldconfig

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To test everything change the path of the terminal to the examples path of qwt and run qmake and make again

Code:

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cd \home\YOU\Qwt-5.2.0\examples
qmake 
sudo make

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now open the examples.pro file with the qcreator and everything should work fine. :)

There's no need to compile with super user privileges. :)

I had to because the folder the files were created to was locked for the normal user ^^. But yes you are right :)

Great! Thanks!

I change only one step of your tutorial.

Instead of add the line /usr/local/qwt-5.2.0/lib in the libc.conf I create the new file qwt.conf in the same directory.

Just a question: what lines you need to use in the project.pro file?

I need to add this:

INCLUDEPATH += /usr/local/qwt-5.2.0-svn/include/
LIBS += /usr/local/qwt-5.2.0-svn/lib/libqwt.so.5

I also try to use CONFIG += Qwt but don't work.