UIView.animateWithDuration(1, animations: { [unowned self] in self.box.center = self.boxTopRightPosition }, completion: { [unowned self] completed in self.box.hidden = true })
有必要避免内存泄漏吗?
不,在这种情况下不需要。animations并且completion不会被保留,self因此没有强大的保留周期的风险。
animations
completion
self