Getting Undefined Reference Error

[A.H.M. Mahfuzur Rahman]

I am getting the error:

mainwindow.cpp:44: undefined reference to `StartWindow::StartWindow(QWidget*)

What is the reason? The code is below:

mainwindow.h

#ifndef MAINWINDOW_H
#define MAINWINDOW_H
 
class MainArea;
class StartWindow;
 
class MainWindow : public QMainWindow
{
    Q_OBJECT
 
    public:
        MainWindow();
        ~MainWindow();
    private slots:
        void newGame();
 
    private:
 
        void setupActions();
 
        MainArea *m_graphicsViewArea;
        StartWindow *m_startWindow;
        KTextEdit *m_textArea;
 
};
 
#endif // MAINWINDOW_H

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

class MainArea;
class StartWindow;

class MainWindow : public QMainWindow
{
    Q_OBJECT

    public:
        MainWindow();
        ~MainWindow();
    private slots:
        void newGame();

    private:

        void setupActions();

        MainArea *m_graphicsViewArea;
        StartWindow *m_startWindow;
        KTextEdit *m_textArea;

};

#endif // MAINWINDOW_H

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mainwindow.cpp

#include "mainwindow.h"
#include "mainarea.h"
#include "startwindow.h"
 
 
//Constructor
MainWindow::MainWindow()
    : QMainWindow()
{
 
 
    m_graphicsViewArea = new MainArea(this);
    m_startWindow = new StartWindow(this); //Here is the error
    setCentralWidget(m_startWindow);
    setWindowTitle("Mancala");
 
    setupActions();
 
}

#include "mainwindow.h"
#include "mainarea.h"
#include "startwindow.h"


//Constructor
MainWindow::MainWindow()
    : QMainWindow()
{


    m_graphicsViewArea = new MainArea(this);
    m_startWindow = new StartWindow(this); //Here is the error
    setCentralWidget(m_startWindow);
    setWindowTitle("Mancala");

    setupActions();

}

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startwindow.h

#ifndef STARTWINDOW_H
#define STARTWINDOW_H
 
class StartWindow : public QGraphicsView{
 
    Q_OBJECT
 
    public:
        StartWindow(QWidget *parent);
 
    private:
 
        QGraphicsSimpleTextItem *m_start_text;
};
 
#endif // STARTWINDOW_H

#ifndef STARTWINDOW_H
#define STARTWINDOW_H

class StartWindow : public QGraphicsView{

    Q_OBJECT

    public:
        StartWindow(QWidget *parent);

    private:

        QGraphicsSimpleTextItem *m_start_text;
};

#endif // STARTWINDOW_H

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startwindow.cpp

#include "startwindow.h"
 
StartWindow::StartWindow(QWidget *parent)
    : QGraphicsView(parent)
{
 
    m_start_text = new QGraphicsSimpleTextItem("This is a collection of Mancala Games");
 
    m_start_text->setFont( QFont("Comic Sans MS", 24, QFont::Bold) );
 
   scene()->addItem(m_start_text);
 
}

#include "startwindow.h"

StartWindow::StartWindow(QWidget *parent)
    : QGraphicsView(parent)
{

    m_start_text = new QGraphicsSimpleTextItem("This is a collection of Mancala Games");

    m_start_text->setFont( QFont("Comic Sans MS", 24, QFont::Bold) );

   scene()->addItem(m_start_text);

}

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Mahfuz

[caduel]

make sure startwindow.cpp is added to your .pro file; maybe you need to run qmake again?

[nish]

#include <QGraphicsView> in startwindow