Problem with Executing Example [SOLVED]

SidRama

I have installed QT from source and everything seems fine. This is the test code I am trying to run:

#include <QApplication>
#include <QTextEdit>

    int main(int argv, char **args)
    {
        QApplication app(argv, args);

        QTextEdit textEdit;
        textEdit.show();

        return app.exec();
   }

I saved this in a folder called QTCode. I then used qmake -project and qmake. However, when I finally call make I get the following error:

g++ -Wl,-O1 -Wl,-rpath,/usr/local/Qt-5.4.1/lib -o QTCode test.o -L/usr/local/Qt-5.4.1/lib -lQt5Gui -lQt5Core -lGL -lpthread
test.o: In function main': test.cpp:(.text.startup+0x27): undefined reference toQApplication::QApplication(int&, char**, int)'
test.cpp:(.text.startup+0x31): undefined reference to QTextEdit::QTextEdit(QWidget*)' test.cpp:(.text.startup+0x39): undefined reference toQWidget::show()'
test.cpp:(.text.startup+0x3e): undefined reference to QApplication::exec()' test.cpp:(.text.startup+0x49): undefined reference toQTextEdit::~QTextEdit()'
test.cpp:(.text.startup+0x51): undefined reference to QApplication::~QApplication()' test.cpp:(.text.startup+0x68): undefined reference toQApplication::~QApplication()'
test.cpp:(.text.startup+0x7b): undefined reference to `QTextEdit::~QTextEdit()'
collect2: error: ld returned 1 exit status
make: *** [QTCode] Error 1

I am not sure if this is a problem with installation. I would be grateful for any help! Thank you!

koahnig

@SidRama
Hi and welcome to devnet

There is actually an example for QTextEdit available.

What do you have in your .pro file?

SidRama

Hi!
Actually, the above program is from an example:
http://doc.qt.io/qt-4.8/gettingstartedqt.html

This is the contents of the .pro file:

TEMPLATE = app
TARGET = QTCode
INCLUDEPATH += .
#Input
SOURCES += test.cpp

In the folder I have a Makefile, a QTCode.pro file, test.cpp and test.o

Thank you!

koahnig

@SidRama
You should use the new example. There are only a couple of differences between Qt4 and Qt5. However, a major difference is probably in the .pro file. That may explain your problem.

SGaist

Hi and welcome to devnet,

@koahnig is right, with Qt 5, the widgets have now their own module separated from gui, so the pro files from Qt 4 won't have QT += widgets that is needed to compile with Qt 5.

SidRama

Hi!
Thank you so much! It turns out that I hadn't installed QT properly and the CLASSPATH was messed up.