What does this error mean?

bootchk

Please be more specific.

I skimmed your post and do not see an error, only warnings (there is a difference.) I don't think most readers want to read 40 lines. Instead, please tell us exactly what error message you are concerned about.

amccarthy

You are using the QString::arg() function which does not modify the original string but returns a new modified string. You are not using the return value, hence your code is essentially a no-op.

IamInu

Hello, Thanks for replying. My previous message was the output I got when trying to compile an example of Qt. I got a very long warning/error message and the program did not work.

I tried a simpler code:
@
#include <QApplication>
#include <QPushButton>

int main(int argc, char *argv[])
{
QApplication app(argc, argv);

QPushButton bouton("Hello World!");
bouton.show();

return app.exec&#40;&#41;;

}
@

It does not work and the error message is:
@
../test/main.cpp:1:24: error: QApplication: No such file or directory
../test/main.cpp:2:23: error: QPushButton: No such file or directory
../test/main.cpp: In function 'int main(int, char**)':
../test/main.cpp:6: error: 'QApplication' was not declared in this scope
../test/main.cpp:6: error: expected ;' before 'app' ../test/main.cpp:8: error: 'QPushButton' was not declared in this scope ../test/main.cpp:8: error: expected ;' before 'bouton'
../test/main.cpp:9: error: 'bouton' was not declared in this scope
../test/main.cpp:11: error: 'app' was not declared in this scope
../test/main.cpp: At global scope:
../test/main.cpp:4: warning: unused parameter 'argc'
../test/main.cpp:4: warning: unused parameter 'argv'
make: *** [main.o] Error 1
@
Any hints? Thanks a lot :)

[Edit: Added @ tags for formatting -- mlong]

SGaist

Hi,

since you'r using Qt5 add QT += qtwidgets to you pro file

guziemic

Hi,

Looks like all Qt objects are missing (compiler does not see includes files). Can you post .pro file?

BR,

IamInu

Hello, this is all what was written automatically in the .pro file:

SOURCES +=
main.cpp

IamInu

@SGaist: I added QT += qtwidgets and here is the error message:

Project ERROR: Unknown module(s) in QT: qtwidgets
make: *** [Makefile] Error 3
make: Leaving directory `/Users/ines/test-build-Desktop_Qt_5_0_1_clang_64bit-Debug'
10:13:10: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project test (kit: Desktop Qt 5.0.1 clang 64bit)
When executing step 'Make'

SGaist

Your pro file does not contain the minimal stuff to build a Qt project. Since your trying things, delete that project and create a new Qt Gui Application with QtCreator. This will give you a starting point to test code

IamInu

I created a Qt Gui Application but again I have this huge list of warnings as output and then this

10:45:48: The process "/usr/bin/make" exited with code 2.
Error while building/deploying project test (kit: Desktop Qt 5.0.1 clang 64bit)
When executing step 'Make'

IamInu

A question, When I compile an example of Qt creator, it should normally work? I tried out different example and each time I have this huge list of warning and errors ...