Pfthb

I am creating object from QGraphicsRectItem and adding to the Qgraphicscene(scene).
I want to get every movement(pos) of object(qgraphicsrectitem) so that I subclassed Qgraphicsrectitem. But in this class I am getting some errors.
How can I get object position changed in scene ?

error:

'staticMetaObject' is not a member of 'QGraphicsRectItem'
{ &QGraphicsRectItem::staticMetaObject, qt_meta_stringdata_ItemHandler.data

ItemHandler.h

#include <QObject>
#include <QGraphicsRectItem>

class ItemHandler : public QGraphicsRectItem, public QObject

 Q_OBJECT

 public:
 ItemHandler(QGraphicsItem *parent = 0 );
 ~ItemHandler();

 protected:
 QVariant itemChange(GraphicsItemChange change, const QVariant &value);

 signals:
 void objectHandlePosChanged(QPointF value);
 ;

ItemHandler.cpp

 #include "itemhandler.h"

 ItemHandler::ItemHandler(QGraphicsItem *parent) : QGraphicsRectItem(parent)
 
 setFlag(QGraphicsItem::ItemSendsGeometryChanges);
 

 ItemHandler::~ItemHandler()
 

 

 QVariant ItemHandler::itemChange(QGraphicsItem::GraphicsItemChange change, 
 const QVariant &value)
 
 QPointF newPos = value.toPointF();
 emit objectHandlePosChanged(newPos);
 

In you header file, inherit first from QObject, as follows:

#include <QObject>
#include <QGraphicsRectItem>

class ItemHandler : public QObject, public QGraphicsRectItem

 Q_OBJECT

 public:
 ItemHandler(QGraphicsItem *parent = 0 );
 ~ItemHandler();

 protected:
 QVariant itemChange(GraphicsItemChange change, const QVariant &value);

 signals:
 void objectHandlePosChanged(QPointF value);
 ;

And this is my test main function (sorry it's just a sandbox):

int main(int argc, char *argv)



 QApplication app(argc, argv);

 MainWindow* mywindow = new MainWindow();

 QGraphicsScene scene;
 ItemHandler *item = new ItemHandler;
 item->setRect(10.0, 10.0, 10.0, 10.0);

 scene.addItem(item);

 QApplication::connect(item, SIGNAL(objectHandlePosChanged(QPointF)), mywindow, SLOT(moved(QPointF)));

 QGraphicsView view(&scene);
 view.setFixedSize(250, 250);
 view.setWindowTitle("QGraphicsItem Test");
 item->setPos(-100, -100);
 item->setPos(-200, -200);
 view.show();
 return app.exec();

I just used an empty MainWindow that is never displayed to have a slot to connect to the signal, there's no point in having a MainWindow: it was already there and I modified it instead of creating a new class. The example works, fires the signal and displays the rectangle.