'If set to `True` then the geometry will be adjusted whenever
the arrow is changed with `setLine`. Otherwise the geometry
of the item is only updated so the `line` lies within the
`geometry()` rect (i.e. it only grows). True by default'

def setAutoAdjustGeometry(self, autoAdjust):

    self.__autoAdjustGeometry = autoAdjust
    if autoAdjust:
        self.adjustGeometry()
