Qt - moc file related error

Question

I am coding a project. I started to getting errors after I tried to make the static build. I made some changes, which I can't remember. But, I am sure that if this stub can be cleared, then the main project also can be get cleared.

This is header file.

#ifndef MYLABEL_H
#define MYLABEL_H

#include <QFileDialog>
#include <QLabel>
#include <QMouseEvent>
#include <QObject>
#include <QPaintEvent>

class MyLabel:public QWidget
{
private:
    QPixmap default_Pixmap;
    QPixmap pixmap;
    QFileDialog * fileDialog;
    Q_OBJECT
public:
    MyLabel();
    void setPixmap(QPixmap pixmap);
    void setDefault();
protected:
    void mousePressEvent(QMouseEvent *event);
    void paintEvent(QPaintEvent * event);
signals:
    void file_Selected(QString fileName);
private slots:
    void file_Got_Selected(QString fileName);

};

#endif // MYLABEL_H

Here is the source file

#include "MyLabel.h"
#include "MyMessageBox.h"
#include <QFileDialog>
#include <QPainter>

MyLabel::MyLabel():QWidget()
{
    default_Pixmap = QPixmap("select.gif").scaled(250,100);
    this->fileDialog=new QFileDialog(this);
    fileDialog->setNameFilter("Image Files (*.BMP *.GIF *.JPG *.JPEG *.PNG *.PBM *.PGM *.PPM *.XBM *.XPM)");
    connect(fileDialog,SIGNAL(fileSelected(QString)),this,SIGNAL(file_Selected(QString)));
    connect(fileDialog,SIGNAL(fileSelected(QString)),this,SLOT(file_Got_Selected(QString)));
}

void MyLabel::setPixmap(QPixmap pixmap)
{
    this->pixmap = pixmap;
}

void MyLabel::setDefault()
{
    this->pixmap = default_Pixmap;
}

void MyLabel::mousePressEvent(QMouseEvent *event)
{
    fileDialog->show();
    //QString file_Name = file_Dialog.getOpenFileName();
}

void MyLabel::paintEvent(QPaintEvent * event)
{
    QPainter painter(this);
    painter.drawPixmap(0,0,width(),height(),pixmap.scaled(QSize(width(),height())));
}

void MyLabel::file_Got_Selected(QString fileName)
{
    this->pixmap = QPixmap(fileName);
}

#include "myLabel.moc"

And this is the main file

#include <QLabel>
#include <QPixmap>
#include <QtGui/QApplication>
#include "myLabel.h"

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);

    MyLabel mm;
    //mm.setPixmap(QPixmap("dummy.jpg"));
    //mm.setPixmap(QPixmap());
    mm.setDefault();
    mm.show();

    return a.exec();
}

I created the moc file using qt command prompt and the command

moc myLabel.h -o myLabel.moc

After this I tried to compile the project through Qt-Editor. But I got multi definition error as follows,

debug/moc_myLabel.o:d:/TempInstallationFolder/Qt/Dynamic/qt/include/QtCore/../../src/corelib/global/qglobal.h:1381: multiple definition of `MyLabel::metaObject() const'

debug/myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/../CalendarNew//myLabel.moc:57: first defined here

debug/moc_myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/debug/moc_myLabel.cpp:62: multiple definition of `MyLabel::qt_metacast(char const*)'

debug/myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/../CalendarNew//myLabel.moc:62: first defined here

debug/moc_myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/debug/moc_myLabel.cpp:70: multiple definition of `MyLabel::qt_metacall(QMetaObject::Call, int, void**)'

debug/myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/../CalendarNew//myLabel.moc:70: first defined here

debug/moc_myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/debug/moc_myLabel.cpp:87: multiple definition of `MyLabel::file_Selected(QString)'

debug/myLabel.o:C:\Documents and Settings\prabhakaran\Desktop\CalendarNew-build-desktop/../CalendarNew//myLabel.moc:87: first defined here

debug/moc_myLabel.o:moc_myLabel.cpp:(.data+0x0): multiple definition of `MyLabel::staticMetaObject'

debug/myLabel.o:myLabel.cpp:(.data+0x0): first defined here

collect2: ld returned 1 exit status

mingw32-make[1]: * [debug\CalendarNew.exe] Error 1

mingw32-make: * [debug] Error 2

The process "D:/TempInstallationFolder/Qt/Dynamic/mingw/bin/mingw32-make.exe" exited with code %2. Error while building project CalendarNew (target: Desktop) When executing build step 'Make'

Anybody please hep me out of this problem.

Answer 1

Try to remove line include "MyLabel.moc" form you source file. You don't need to include it into cpp file.