用cmake编译qt库

我为我愚蠢的问题感到抱歉。我正试图用cmake从带有Qt对象的类编译dll。库包含使用其他文件中定义的类的函数。在链接过程中，我得到了对类成员的错误“未定义引用”。 CMakeList.txt中的错误在哪里

CMakeList.txt：

cmake_minimum_required(VERSION 2.8) 
project(foo)            
set(SOURCE_LIB foo.cpp window.cpp)          
find_package (Qt4 REQUIRED)
include (${QT_USE_FILE})
ADD_DEFINITIONS(-DFOO_LIBRARY)
add_library(foo SHARED ${SOURCE_LIB})   
target_link_libraries(foo ${QT_LIBRARIES})

foo.h:

#ifndef FOO_H
#define FOO_H

#include "foo_global.h"

void FOOSHARED_EXPORT hello_world();
#endif // FOO_H

foo.cpp：

#include <QApplication>
#include <QMessageBox>
#include "window.h"

void hello_world()
{
    int argc = 0;
    char ** argv = (char **) 0;
    QApplication a(argc, argv);
    Window *w = new Window();
    w->Msg();
}

---

包含

Q_OBJECT

宏的类的所有头都必须由元对象编译器处理。 因此，您的cmake文件应如下所示：

cmake_minimum_required(VERSION 2.8) 
project(foo)            
set(LIB_SOURCE foo.cpp window.cpp)          
set(LIB_HEADER foo.h)
find_package (Qt4 REQUIRED)
include (${QT_USE_FILE})
ADD_DEFINITIONS(-DFOO_LIBRARY)

QT4_WRAP_CPP(LIB_HEADER_MOC ${LIB_HEADER})

add_library(foo SHARED ${LIB_SOURCE} ${LIB_HEADER_MOC})   
target_link_libraries(foo ${QT_LIBRARIES})

#include <QMessageBox>
#include "window.h"

void Window :: Msg()
{
    QMessageBox *msg = new QMessageBox();
    msg->setText("hello");
    msg->exec();
}

#ifndef WINDOW_H
#define WINDOW_H

#include <QtGui>

class Window
{
    Q_OBJECT
public:
    void Msg();

};

#endif // WINDOW_H

Test\build>c:\MinGW\bin\mingw32-make.exe
Scanning dependencies of target foo
[ 50%] Building CXX object CMakeFiles/foo.dir/foo.cpp.obj
[100%] Building CXX object CMakeFiles/foo.dir/window.cpp.obj
Linking CXX shared library libfoo.dll
Creating library file: libfoo.dll.a
CMakeFiles\foo.dir/objects.a(foo.cpp.obj):foo.cpp:(.text$_ZN6WindowC1Ev[Window::
Window()]+0x8): undefined reference to `vtable for Window'
collect2: ld returned 1 exit status
mingw32-make[2]: *** [libfoo.dll] Error 1
mingw32-make[1]: *** [CMakeFiles/foo.dir/all] Error 2
mingw32-make: *** [all] Error 2

cmake_minimum_required(VERSION 2.8) 
project(foo)            
set(LIB_SOURCE foo.cpp window.cpp)          
set(LIB_HEADER foo.h)
find_package (Qt4 REQUIRED)
include (${QT_USE_FILE})
ADD_DEFINITIONS(-DFOO_LIBRARY)

QT4_WRAP_CPP(LIB_HEADER_MOC ${LIB_HEADER})

add_library(foo SHARED ${LIB_SOURCE} ${LIB_HEADER_MOC})   
target_link_libraries(foo ${QT_LIBRARIES})