Basic question: Including headers with INCLUDEPATH doesn't work

Binary91

By the way:
the problem really is Q_OBJECT...

I just wrote "Q_OBJECT" into the myQString class and look what happened: undefined reference vtable ... in myQString.cpp!

So Q_OBJECT makes the problems why I have to add all headers to the project! How can I avoid this?

mrjj

when u add Q_OBJECT, please run qmake!

Binary91

I already tried that.
Building, running
Building, qmake, running
qmake, running
qmake, building, running

None of the above ways succeded

mrjj

@Binary91
then please as last test
Complete delete the build folder.

Binary91

tried that, two.

Deleted everything but my project file and the sources/headers. Didn't work :-(

Is it possible that qmake ignores INCLUDEPATH?

mrjj

@Binary91
Well anything seems possible with your setup. :)
Q_OBJECT should not bork anything.

Im out of ideas :)

Binary91

Well, I'll post the whole project file, its headers and sources and maybe you can copy/paste it and try to run it with?

If it works, then it is a setting problem. If not, something with my include logic doesn't work.

project file:

#-------------------------------------------------
#
# Project created by QtCreator 2016-11-17T15:45:17
#
#-------------------------------------------------

QT       += core gui

greaterThan(QT_MAJOR_VERSION, 4): QT += widgets

TARGET = CourseCalculator
TEMPLATE = app

INCLUDEPATH += C:/Qt/lib/headers

HEADERS  += main.h

SOURCES += main.cpp
           C:/Qt/lib/sources/myQString.cpp \
           C:/Qt/lib/sources/myQLineEdit.cpp \
           C:/Qt/lib/sources/myQPushButton.cpp

main.cpp:

// main.cpp

#include "main.h"

int main(int argc, char *argv[])
{
  QApplication applicationApp(argc, argv);
  clsWindowMain windowMain;

  QTimer::singleShot(0, &windowMain, SLOT(slotStart()));
  int ret = applicationApp.exec();
  return ret;
}

main.h:

// main.h

#ifndef MAIN_H
#define MAIN_H

#include <QApplication>
#include <QTimer>
#include <QWidget>
#include <QDialog>

#endif // MAIN_H

myQLineEdit.h:

// myQLineEdit.h

#ifndef MYQLINEEDIT_H
#define MYQLINEEDIT_H

#include <QDebug>
#include <QLineEdit>
#include <QMessageBox>
#include <QDir>


// forward declaration

class myQLineEdit;


// declaration

class myQLineEdit : public QLineEdit
{
  Q_OBJECT

  // .. properties

  public:
    myQLineEdit(QWidget* widgetParent = 0);
    ~myQLineEdit();

    // .. more methods
};

#endif

myQLineEdit.cpp:

// myQLineEdit.cpp

#include <myQLineEdit.h> // absolute path or absolute path with whitespaces also doesn't work


// ----- constructors -----

myQLineEdit::myQLineEdit(QWidget* widgetParent) : QLineEdit(widgetParent)
{
   // stuff
}

Is that compilable for you?

mrjj

@Binary91
would be very much easier if you zipped folder and shared via dropbox or g drive as
copy paste to real files again is very error prone and time consuming :)

Binary91

Good idea. But my dropbox accout has no free memory left :-D

Have to create a new account first, maybe on g drive...

mrjj

@Binary91
well a zipped project is ultra small. so delete/remove something for a moment and it should have space :)

btw: G Drive is 15 GB but the client is nowhere near as nice as dropbox.

jsulm

@Binary91 If you derive from Qt classes which are derived from QObject then you need to include the generated moc_ files.
For example in myQLineEdit.cpp add

#include "moc_myQLineEdit.cpp"

Binary91

but from where do I get this moc file?
If I try to include, compiler gives me an error that it can not find such file or directory

btw:
https://www.dropbox.com/s/whqdkcat767224t/test.zip?dl=0

jsulm

@Binary91 You should read the Qt documentation. The moc_ files are generated for you using moc tool. Take a look at the build directory.

jsulm

@Binary91 Why do you have a main.h? This is quite unusual.

jsulm

@Binary91 For QApplication you need QT += gui, else you should use QCoreApplication.

Buckwheat

@jsulm , why would you include the MOC files? I "never" include the MOC files in my source because they get generated, compiled, and linked after the normal build. The only generated file I would include is the ui_NameOfForm.h file created when using the form designer. And, only in the CPP for the UI class.

@Binary91 , I am sure it was explained that INCLUDEPATH tells qmake where to find common include files. I use it for 3rd party libraries or pre-built packages I developed for Qt (I treat them like 3rd party libraries). And, as I know you know... always run qmake after changing a PRO file.

There is one curious item I have found about QtCreator though... if you are using static libraries (even if your dependencies are setup) and make a change to a CPP file in the library... Press build-all and it will build the library and NOT re-link the application or shared library that depends on that static library. Kind of annoying but I just get around it!

Binary91

I know what moc files are, but they were not permanently created by QtCreator (not in my build folder).
But can you tell me why I should have to generate them and manually include them when it works to simply add the headers to the project?
I mean, I wanted to reduce work by using INCLUDEPATH and NOT adding all the included headers.
Generating moc files and manually adding them is not reducing but increasing work.

Also I do not understand why I should include them when I don't need it if I add the headers directly...

jsulm

@Binary91 Where is myudp.cpp ?

jsulm

@jsulm With some fixes I can build your project.
pro file:

QT       += core network

QT       -= gui

TARGET = test
CONFIG   += console
CONFIG   -= app_bundle

TEMPLATE = app

INCLUDES += lib/headers/myQLineEdit.h

SOURCES += main.cpp \
    #myudp.cpp

#HEADERS += \
#    myudp.h

main.cpp

#include <QCoreApplication>

int main(int argc, char *argv[])
{
  QCoreApplication applicationApp(argc, argv);
  //clsWindowMain windowMain;

  //QTimer::singleShot(0, &windowMain, SLOT(slotStart()));
  int ret = applicationApp.exec();
  return ret;
}

jsulm

@Binary91 Where I did say you have to create moc_ files manually?
They are generated for you. And they are completely unrelated to your problem!