QT没有这样的插槽

我有这样一段代码:

przystanki.h

#ifndef PRZYSTANKI_H
#define PRZYSTANKI_H
#include "component.h"
class Przystanki : public Component
{
public:
    Przystanki(QWidget *parent = 0);
signals:
    void deletePosition(QString);
public slots:
    void deleteListItem();
    void addListItem(QString label);
    void createListItem(QString label, DodajPrzystanek* elem);
};
#endif // PRZYSTANKI_H

component.h

#ifndef COMPONENT_H
#define COMPONENT_H
#include <QListWidget>
#include <QGroupBox>
#include "dodajprzystanek.h"
class Component : public QGroupBox
{
    Q_OBJECT
public:
    explicit Component(QString name, QWidget *parent = 0);
    QListWidget* list;
};
#endif // COMPONENT_H

片段:

MyWindow::MyWindow(QWidget *parent) :
QMainWindow(parent)
{
webView = new MyWebView(this);
mainlayout = new QGridLayout();
mainlayout->addWidget(webView, 0,0);
Przystanki *stop = new Przystanki(this);
mainlayout->addWidget(stop, 0, 1);
QHBoxLayout* bottom = new QHBoxLayout();
//bottom->addWidget(new QLabel("Linie"));
bottom->addWidget(new Component("Autobusy"));
bottom->addWidget(new Component("Linie"));
QHBoxLayout* hrightCorner = new QHBoxLayout();
QVBoxLayout* rightCorner = new QVBoxLayout();
rightCorner->addStretch(1);
rightCorner->addWidget(new QPushButton("Start", this));
//QLabel* label = new QLabel("Labelka");
//rightCorner->addWidget(label);
rightCorner->addStretch(1);
hrightCorner->addLayout(rightCorner);
mainlayout->addLayout(bottom, 1, 0);
mainlayout->addLayout(hrightCorner, 1, 1);
hrightCorner->setAlignment(Qt::AlignCenter);
this->setCentralWidget(new QWidget);
this->centralWidget()->setLayout(mainlayout);
connect(webView, SIGNAL(getMapPosition(QString)), stop, SLOT(addListItem(QString)));
connect(stop, SIGNAL(deletePosition(QString)), webView, SLOT(deleteMarker(QString)));

}

我得到的是:

loaded the Generic plugin 
Object::connect: No such slot Component::addListItem(QString)
Object::connect: No such signal Component::deletePosition(QString)

它发生后，我移动槽和信号的定义从组件到它的派生类Przystanki。我已经删除了整个构建目录，运行clean，运行qmake和构建一次，它没有帮助。有人能告诉我我哪里做错了吗?