QApplication a(argc, argv);

// create a scene

QGraphicsScene * scene = new QGraphicsScene();

// create an item to add to the scene

MyRect * player = new MyRect();

player->setRect(0,0,100,100); // change the rect from 0x0 (default) to 100x100 pixels

// add the item to the scene

scene->addItem(player);

// make rect focusable

player->setFlag(QGraphicsItem::ItemIsFocusable);

player->setFocus();

// create a view to visualize the scene

QGraphicsView * view = new QGraphicsView(scene);

view->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);

view->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);

// show the view

view->show();

view->setFixedSize(800,600);

scene->setSceneRect(0,0,800,600);

player->setPos(view->width()/2,view->height() - player->rect().height());

return a.exec();