QT 4.5 - Changing the selection marquee for QGraphicsItem

Question

Is it possible to define the style of the selection marquee when a QGraphicsItem is set selectd via setSelected(true)?

Zemstvo

Answer 1

There's a good solution at:

http://www.qtcentre.org/threads/15089-QGraphicsView-change-selected-rectangle-style

Barbarity

Note to anyone finding this: This new answer is what you want; a much better answer than the earlier accepted answer. – Domingadomingo

Answer 2

Technically no.

After a quick look into Qt's source code, it seems that the standard item types QGraphics*Item have the dashed outline as a default behavior. You can work around this by subclassing your own QGraphicsItem.

if (option->state & (QStyle::State_Selected | QStyle::State_HasFocus))
    qt_graphicsItem_highlightSelected(this, painter, option);

I guess you can not change the "style". This seems to be a very static feature of the standard QGraphicsItems.

Hope that helps!

Lanell

@Barbarity actually found a great workaround, see other answer. – Domingadomingo

Answer 3

Just adding to cesarbs' answer with a python example, it took me a bit to translate all the syntax so thought I'd provide some code:

class CustomItem(QtWidgets.QGraphicsPixmapItem):
    def paint(self, painter, option, widget):
        if option.state & QtWidgets.QStyle.State_Selected:
            option.state &= not QtWidgets.QStyle.State_Selected
            super().paint(painter, option, widget)
            
            # draw red outline for example
            pen = QtGui.QPen(QtGui.QColor("red"))
            painter.setPen(pen)
            painter.drawRect(option.rect)
        else:
            super().paint(painter, option, widget)

Alethiaaletta