QScene doesn't retrive topmost item ?

[AtlasS]

I tried to lock them, but it was no good. Each and every square is an QPixmapItem defined inside a class called square. Being Pixmap items, I guess they're movable at all times, especially when using the "itemAt(*mousePress)->setPos(point *x)..

[norobro]

Can you not set your board up like this?

#include <QtGui>
 
int main(int argc, char** argv)
{
    QApplication app(argc, argv);
    QGraphicsScene scene;
    for(int row=0; row<=7; ++row) {
        int x=0;
        int y= row*50;
        for(int col=0; col<=7;++ col) {
           QGraphicsRectItem *square = new QGraphicsRectItem(x, y, 50, 50); // not moveable by default
            if(!(row%2 ^ col%2)) square->setBrush(QBrush(Qt::white));
                    else square->setBrush(QBrush(Qt::black));
            scene.addItem(square);  
            x += 50;
        }
    }
    QGraphicsItem *piece = scene.addEllipse(7, 7, 35, 35, QPen(),QBrush(Qt::red)); // checker :) in lieu of chessman
    piece->setFlag(QGraphicsItem::ItemIsMovable); // make checker movable
    QGraphicsView view(&scene);
    view.show();
    return app.exec();
}

#include <QtGui>

int main(int argc, char** argv)
{
    QApplication app(argc, argv);
    QGraphicsScene scene;
    for(int row=0; row<=7; ++row) {
        int x=0;
        int y= row*50;
        for(int col=0; col<=7;++ col) {
           QGraphicsRectItem *square = new QGraphicsRectItem(x, y, 50, 50); // not moveable by default
            if(!(row%2 ^ col%2)) square->setBrush(QBrush(Qt::white));
                    else square->setBrush(QBrush(Qt::black));
            scene.addItem(square);  
            x += 50;
        }
    }
    QGraphicsItem *piece = scene.addEllipse(7, 7, 35, 35, QPen(),QBrush(Qt::red)); // checker :) in lieu of chessman
    piece->setFlag(QGraphicsItem::ItemIsMovable); // make checker movable
    QGraphicsView view(&scene);
    view.show();
    return app.exec();
}

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[AtlasS]

Pretty nice & effective piece of code : ) but in that way,I don't have total control over "the data" of the squares. For example, I won't be able to tell if the square is white,black, occupied or not.

Thank you very much for your effort, but I fixed the error finally by straight luck .
Problems were :

1-Dynamic cast : I didn't typecast the fetched element from the scene.
2-The painting : here's the code ,
looks like the items moved, but were invisible xD, because of the QRectF return value (which is nothing), so everything was getting re-drawn in small pixels (very small).

QRectF BoardSquare::boundingRect() const
{
 
    return QRectF(0,0,30,30); //Here was the error, QRectF ( ) was the return value, then I fixed it to QRectF(0,0,30,30)
 
}
 
void BoardSquare:: paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
                        QWidget *widget)
{
   QPoint s;
   painter->drawImage(s,*g);
 
 
 
 }

QRectF BoardSquare::boundingRect() const
{

    return QRectF(0,0,30,30); //Here was the error, QRectF ( ) was the return value, then I fixed it to QRectF(0,0,30,30)

}

void BoardSquare:: paint(QPainter *painter, const QStyleOptionGraphicsItem *option,
                        QWidget *widget)
{
   QPoint s;
   painter->drawImage(s,*g);



 }

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Conclusion of the error & debugging :

The fetched item was a copy, not the real one, fetched and redrawn in a very small size. After using the "Dynamic cast", I was capable of returning the original element.

Afrer fixing the returned value from BoundingRect () function, the item was redrawn perfectly .

Thanks norobro for you effort : ) I will sure put your help into use & consideration in the future.