- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer//Asks the delegate if a gesture recognizer should begin interpreting touches. - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldReceiveTouch:(UITouch *)touch//Ask the delegate if a gesture recognizer should receive an object representing a touch.
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRequireFailureOfGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer - (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldBeRequiredToFailByGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer
原文：http://www.cnblogs.com/zhongriqianqian/p/3986685.html