Hi. Check this code:
void centerItemInRect(QGraphicsItem *item, QRectF rect)
{
float x = rect.width() -
item->boundingRegion(item->transform()).boundingRect().width();
x /= 2;
float y = rect.height() -
item->boundingRegion(item->transform()).boundingRect().height();
y /= 2;
item->setPos(x + rect.x(), y + rect.y());
}
This code works if you use Transformation on QGItem. It does not work if
you set scale and rotation with setRotation and setScale.
On Wed, Nov 23, 2016 at 4:15 AM, Ch'Gans <chg...@gna.org> wrote:
> Hi there,
>
> I'm trying to add a QGraphicsSimpleTextItem as a child of another (shape)
> item.
> I want the text to not follow scaling of the view (I use
> QGraphicsItem::ItemIgnoreTransformations flag), *and* be always
> centered on it's parent shape.
> Ideally, i'm looking at a solution that doesn't require to create a
> custom QGItem.
>
> My problem is the centering of the text item itself, without
> centering, here is what i do:
> ------------------------------------------------------------
> ------------------------------
> auto item = new ...
> ...
> auto text = new QGraphicsSimpleTextItem(item);
> text->setText(...);
> text->setFlag(QGraphicsItem::ItemIgnoresTransformations);
> auto itemCenter = QPointF(item->boundingRect().width()/2.0,
> item->boundingRect().height()/
> 2.0);
> text->setPos(itemCenter);
> ------------------------------------------------------------
> ------------------------------
>
> This work fine, but (as expected) the top-left of the text is
> positioned on the center of the parent item.
> To center-align, I tried:
> ------------------------------------------------------------
> -------------------------------
> auto textCenter = QPointF(text->boundingRect().width()/2.0,
> text->boundingRect().height()/
> 2.0);
> text->setTransform(QTransform::fromTranslate(-textCenter.x, -textCenter));
> ------------------------------------------------------------
> -------------------------------
>
> But this doesn't work because textCenter is an offset in a coordinate
> system that doesn't follow view scaling... and the text transform
> seems to be applied in the "scaled space".
>
> Basically my problem is that it seems that I need a dynamic
> positioning wrt the parent that depends on the view transform...
>
> Does anyone know some tricks on how to achieve this?
>
> Thanks,
> Chris
> _______________________________________________
> Interest mailing list
> Interest@qt-project.org
> http://lists.qt-project.org/mailman/listinfo/interest
>
_______________________________________________
Interest mailing list
Interest@qt-project.org
http://lists.qt-project.org/mailman/listinfo/interest
