#include <QtGui>

static QGraphicsScene *myScene;
static QList<QGraphicsRectItem *> *myList;

class GraphicsView: public QGraphicsView
{
	Q_OBJECT

public:
	GraphicsView(QGraphicsScene *scene, QWidget *parent): 
		QGraphicsView(scene,parent) {}

public slots:
	void moveToBackground();
};

void GraphicsView::moveToBackground() 
{
	QGraphicsItem *item=myList->at(2);
	//myScene->removeItem(item);
	item->setZValue(0);
	//myScene->addItem(item);
}

#include "main.moc"

int main(int argc, char **argv)
{
	QApplication app(argc, argv);

	QGraphicsScene scene;
	myScene=&scene;
	scene.setSceneRect(0, 0, 800, 480);
	scene.setItemIndexMethod(QGraphicsScene::NoIndex);

	QList<QGraphicsRectItem *> list;
	myList=&list;
	list.append(new QGraphicsRectItem(10,15,20,25));
	list.append(new QGraphicsRectItem(20,17,20,25));
	list.append(new QGraphicsRectItem(14,24,20,25));

	QColor colors[3]={
		QColor(Qt::red),	//z==1
		QColor(Qt::green),	//z==2
		QColor(Qt::blue)	//z==3
	};

	for (int i=0; i < 3; ++i) {
		list[i]->setFlag(QGraphicsItem::ItemIsMovable);
		list[i]->setFlag(QGraphicsItem::ItemIsSelectable);
		list[i]->setZValue(i+1);
		list[i]->setPen(QPen(colors[i]));
		scene.addItem(list[i]);
	}
	scene.setBackgroundBrush(Qt::white);
	GraphicsView *view = new GraphicsView(&scene,NULL);
	QAction *pAct=new QAction(view);
	new QShortcut(QString::fromLatin1("A"),view,SLOT(moveToBackground()),SLOT(moveToBackground()));
	QObject::connect(pAct,SIGNAL(triggered()),view,SLOT(moveToBackground()));

	view->show();
	return app.exec();
}