c++ - Qt:对`vtable 的 undefined reference

Question

当我尝试编译我的程序时出现错误

obj/backgroundWorker.o: In function `BackgroundWorker':
.../backgroundWorker.cpp:6: undefined reference to `vtable for BackgroundWorker'
obj/backgroundWorker.o: In function `~BackgroundWorker':
.../backgroundWorker.cpp:14: undefined reference to `vtable for BackgroundWorker'

我已经找到了这个错误的许多原因，但到目前为止，我找不到解决我的代码中的问题:

backgroundWorker.hpp

#include <QObject>
#include <QPushButton>

class BackgroundWorker : public QWidget{

    Q_OBJECT

    public:
        explicit BackgroundWorker();
        ~BackgroundWorker();

        private slots:
            void start();

    private:
        QPushButton* mStartButton;
};

backgroundWorker.cpp

#include <iostream>
#include "getInput.hpp"
#include "backgroundWorker.hpp"
#include "LIF_network.hpp"

BackgroundWorker::BackgroundWorker(){
    mStartButton = new QPushButton("Start",this);
    mStartButton->setGeometry(QRect(QPoint(100,100),QSize(200,50)));

    connect(mStartButton, SIGNAL(released()), this, SLOT(start()));
}

BackgroundWorker::~BackgroundWorker(){
    delete mStartButton;
}

void BackgroundWorker::start(){
    //stuff not related to qt
}

main.cpp

#include <QApplication>
#include "backgroundWorker.hpp"

int main(int argc, char *argv[]){
    QApplication a(argc, argv);
    BackgroundWorker bw;
    return a.exec();
}

** .pro 文件**

CONFIG += qt debug c++11
QT += widgets

QMAKE_CC = clang++
QMAKE_CXX = clang++
QMAKE_CXXFLAGS += -Wall -Werror -O3
Headers += image.hpp \
            getInput.hpp \
            LIF_network.hpp \
            backgroundWorker.hpp \

SOURCES += main.cpp \
            image.cpp \
            getInput.cpp \
            LIF_network.cpp \
            backgroundWorker.cpp \


OBJECTS_DIR = ./obj

Answer 1

正如 Frank Osterfeld 在评论中提到的，变量的专有名称是大写的 HEADERS。它应该包含所有包含 Q_OBJECT 宏的 header

这是必需的，因为 qmake 需要知道要提供给 moc 的头文件列表。