keyPressedEvent error Qt when implementing function

Question

I'm getting an error in a qt program where im trying to capture keystrokes. In the keyPressedEvent function in my qt program but i'm geting a weird error:

frenzywindow.cpp:16:50: error: no 'void FrenzyWindow::keyPressEvent(QKeyEvent*)' member function declared in class 'FrenzyWindow'
make: *** [frenzywindow.o] Error 1

The class extends qmainwindow

heres my header file:

#ifndef FRENZYWINDOW_H
#define FRENZYWINDOW_H

#include <QMainWindow>
#include "frenzy.h"

namespace Ui {
class FrenzyWindow;
}

class FrenzyWindow : public QMainWindow
{
    Q_OBJECT

public:
    explicit FrenzyWindow(QWidget *parent = 0);
    ~FrenzyWindow();

signals:
    void moveUp();
    void moveDown();
    void moveLeft();
    void moveRight();


private:
    Ui::FrenzyWindow *ui;
    Frenzy f;
};

#endif // FRENZYWINDOW_H

here is my cpp file:

#include "frenzywindow.h"
#include "ui_frenzywindow.h"

FrenzyWindow::FrenzyWindow(QWidget *parent) :
    QMainWindow(parent),
    ui(new Ui::FrenzyWindow)
{
    ui->setupUi(this);
}

FrenzyWindow::~FrenzyWindow()
{
    delete ui;
}

void FrenzyWindow::keyPressEvent(QKeyEvent *event)
{

    switch(event->key())
    {
    case Qt::UpArrow:
        emit moveUp();
        break;
    case Qt::DownArrow:
        emit moveDown();
        break;
    case Qt::LeftArrow:
        emit moveLeft();
        break;
    case Qt::RightArrow:
        emit moveRight();
        break;
    default:
            event->ignore();
            break;

    }
}

Answer 1

Did you read the compiler error? That's exactly what the problem is. You need to define keyPressEvent in your header file.

protected:
    void keyPressEvent(QKeyEvent *event);