QGraphicsItem move parent instead of child...

[Dariusz]

Hey

When I select child&move it, I'd like that the movement would happen to parent and child moved in relation to parent as a result.

I'm trying to use itemChange function for it, but when I set pos on parrent the offset appear to be wrong... how can I adjust it ?

QVariant myItem::itemChange(QGraphicsItem::GraphicsItemChange change, const QVariant &value) {
    if (change == QGraphicsItem::ItemPositionChange) {
        qDebug() << value;
        mParentItem->setPos(value.toPointF()); // do I need some kind of offset between child pos & parent pos ? 
        return pos(); // cancel movement change on this item. 
    }
    return QGraphicsLineItem::itemChange(change, value);
}

[Bonnie]

Since QGraphicsItem::pos()

Returns the position of the item in parent coordinates.

So the item and its parent item are not in the same coordinate system.
I think you should calculate the offset between pos() and value, then calculate the new pos of mParentItem by adding offset to mParentItem->pos().