在Qt中创建C ++库

Question

I'm new in linux and Qt and I'm trying to create c++ library in Qt. I have library called imaglib with several classes in it. I have done this so far:

imaglib_global.h:

#ifndef IMAGLIB_GLOBAL_H
#define IMAGLIB_GLOBAL_H

#include <QtCore/qglobal.h>

#if defined(IMAGLIB_LIBRARY)
#  define IMAGLIBSHARED_EXPORT Q_DECL_EXPORT
#else
#  define IMAGLIBSHARED_EXPORT Q_DECL_IMPORT
#endif

#endif // IMAGLIB_GLOBAL_H

imaglib.h:

#ifndef IMAGLIB_H
#define IMAGLIB_H

#include "imaglib_global.h"
#include "imagClass.h"

class IMAGLIBSHARED_EXPORT IMaglib
{

public:
    IMaglib();
};

#endif // IMAGLIB_H

imagClass.h:

#include "imaglib_global.h"

class IMAGLIBSHARED_EXPORT imagClass
{

public:
    imagClass();

    void ImagOperation();

    // Other data goes here
};

// there are several imag classes

When I build this it works and creates, in a debug folder .o files and .so, .so.1, .so.1.0 and .so.1.0.0 but when I try to include this in a application it doesn't work. I've tried to copy these files in a folder called imagLib in my project and added this code in application.pro file:

TARGET = MyApp
TEMPLATE = app

DEPENDPATH += imagLib
INCLUDEPATH += imagLib
LIBS+=  -L imaglib/debug -llibiMaglib 
// It creates libiMaglib.so file so I thought I should use this one but it gives me error on compilation "cannot find -llibiiMaglib"

After that I've tried to build library from terminal:

ar crv imaglibrary.so imaglib.o imagClass.o

but it gives me same error when I try to build application with imaglibrary.so and it gives me the same error. How to fix this?

EDIT

I have also tried to create .lib file in terminal and include it in application.pro file like .so file shown above. It works but it gives me different error:

"undefined reference to imagClass::ImagOperation()" when I try to create object and call it from code.

Answer 1

If the name of the built library is "libimaglib", then you should use the -l switch like this

-limaglib

You could think of it as -l replaces "lib". Hope that helps!