QGraphicsRectItem and QGraphicsTextItem.

[wagmare]

but how to obtain a text centered both vetically and horizontally in the rectangle?

thats what i am suggesting .. combine both the text and rectangle into single QGraphicsItem ..

paint such that
create a custom QGraphicsItem()

class CustomItem : public QGraphicsRectItem
{
        Q_OBJECT
 
public:
        CustomItem(const QRectF &rect);
        void paint(QPainter *painter, const  QStyleOptionGraphicsItem *, QWidget *);
        QRectF boundingRect();
 
};

class CustomItem : public QGraphicsRectItem
{
        Q_OBJECT

public:
        CustomItem(const QRectF &rect);
        void paint(QPainter *painter, const  QStyleOptionGraphicsItem *, QWidget *);
        QRectF boundingRect();
   
};

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CustomItem::CustomItem(const QRectF &rect)
            : QGraphicsRectItem(rect)
{
     textItem->setDefaultTextColor(QColor(255,255,255,255));
        textItem->setPos(x, y);              //here u set position of text 
   textItem->setPlainText(message);      //set your text here   
}
 
void CustomItem::paint(QPainter *painter, const  QStyleOptionGraphicsItem *o, QWidget *widget)
{
 painter->setBrush(QBrush(QColor(21, 155, 210, 255)));
        painter->drawRect(rect());
 
}

CustomItem::CustomItem(const QRectF &rect)
            : QGraphicsRectItem(rect)
{
     textItem->setDefaultTextColor(QColor(255,255,255,255));
        textItem->setPos(x, y);              //here u set position of text 
   textItem->setPlainText(message);      //set your text here   
}

void CustomItem::paint(QPainter *painter, const  QStyleOptionGraphicsItem *o, QWidget *widget)
{
 painter->setBrush(QBrush(QColor(21, 155, 210, 255)));
        painter->drawRect(rect());

}

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now the item is ready in horizontal ... now in parent graphicsView() rotate it using previous code ...