我有一个重写的UIGestureRecogniser设计用于检测2次触摸，但不一定是一个接一个地检测。我有:-(BOOL)canBePreventedByGestureRecognizer:(UIGestureRecognizer*)preventingGestureRecognizer{if([preventingGestureRecognizerisKindOfClass:[UIRotationGestureRecognizerclass]]){self.state=UIGestureRecognizerStateCancelled;returnYES;}if([preventin