Unsolved Undefined reference to signal

[AlvaroS]

Hello everyone:

Thanks for reading this post and being able to help.

I would like to create a signal to call a slot in another class.

My code looks like:

header:

class scene_mouse_event : public QGraphicsScene
{

    Q_OBJECT

public:
        scene_mouse_event(QObject* parent = 0);

        void mousePressEvent(QGraphicsSceneMouseEvent *event);
        QPointF pt;


signals:
        void emit_mouse_pressed();


};

#endif // SCENE_MOUSE_EVENT_H

.cpp

#include "mainwindow.h"
#include "ui_mainwindow.h"
#include <QtGui>
#include <QApplication>
#include "scene_mouse_event.h"


scene_mouse_event::scene_mouse_event(QObject* parent): QGraphicsScene(parent){

}

void scene_mouse_event::mousePressEvent(QGraphicsSceneMouseEvent *event)
{
    this->pt = event->scenePos();
    emit emit_mouse_pressed();
    QGraphicsScene::mousePressEvent(event);
}

but it gives me an error in "emit emit_mouse_pressed();":
scene_mouse_event.cpp:15: error: undefined reference to `scene_mouse_event::emit_mouse_pressed()'

and this in the constructor:
scene_mouse_event.cpp:8: error: undefined reference to `vtable for scene_mouse_event'

What's happening?
Thanks!

[mrjj]

hi, you need to run qmake from the build menu.
if it still stupid, then clean the build folder and rebuild all :)