base.py 文件源码

def __init__(self, model):
        pg.GraphicsWidget.__init__(self)
        pg.GraphicsWidgetAnchor.__init__(self)

        self.model = model

        self.arrow = pg.ArrowItem(
            parent=self,
            angle=0.,
            brush=(0, 0, 0, 180),
            pen=(255, 255, 255),
            pxMode=True)
        self.orientArrow()

        self.model.sigSceneChanged.connect(self.orientArrow)
        self.setFlag(self.ItemIgnoresTransformations)