在项目开发的时候我们可能会遇到这样的需求.将UISwipeGestureRecognizer和UIPanGestureRecognizer 加到同一View.然后还要区分出什么时候是Pan什么时候是Swipe.在再开发的时候突然遇到这样一个需求,查了一些资料这个问题算是解决了.希望能帮助有同样需求的人.话不多说直接上代码.
1.首先实例两个手势:
UISwipeGestureRecognizer *swipeGestureRight = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(swipeEvent:)];
swipeGestureRight.direction = UISwipeGestureRecognizerDirectionRight;
[self.view addGestureRecognizer:swipeGestureRight];
UIPanGestureRecognizer *panGesture = [[UIPanGestureRecognizer alloc] initWithTarget:self action:@selector(panEvent:)];
[self.view addGestureRecognizer:panGesture];
这个时候你运行发现只会走Pan手势完全不会走Swipe.
2.做这样一个设置就可以区分Pan和Swipe
[panGesture requireGestureRecognizerToFail:swipeGestureRight];
这个方法在文档中的描述是这样的:
- (void)requireGestureRecognizerToFail:(UIGestureRecognizer *)otherGestureRecognizer
This method creates a relationship with another gesture recognizer that delays the receiver’s transition out of UIGestureRecognizerStatePossible. The state that the receiver transitions to depends on what happens with otherGestureRecognizer:
If otherGestureRecognizer transitions to UIGestureRecognizerStateFailed, the receiver transitions to its normal next state.
if otherGestureRecognizer transitions to UIGestureRecognizerStateRecognized or UIGestureRecognizerStateBegan, the receiver transitions to UIGestureRecognizerStateFailed.
意思是后面的这个手势要是识别成功的话就不会执行前一个手势了.如果后一个手势的state是UIGestureRecognizerStateFailed 接收者转换到其正常的下一个状态。换句话说它会优先识别Swipe手势如果不是swipe再识别是否是Pan手势.如果识别是Swipe则就执行Swipe的方法.不走Pan方法了.
PS:要想识别为Pan手势滑动的时候一定要尽量慢一些,否则直接就识别为Swipe了.
3.如果这样还是不行的话你可以做一个这样的设置:
当前类遵循UIGestureRecognizerDelegate然后指定代理对象:
swipeGestureRight.delegate = self;
panGesture.delegate = self;
然后执行
- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer
shouldRecognizeSimultaneouslyWithGestureRecognizer:
(UIGestureRecognizer *)otherGestureRecognizer {
return YES;}
这个代理方法.
这个delegate的作用是否允许手势识别器同时识别两个手势.YES允许,NO不允许. 这样应该就可以了! 有什么问题的话希望大家指出,必虚心接受.
PS:这个同样适用其他的手势冲突.比如Tap手势设置为单击和双击两个,放在同一个View上也会有冲突,这个方法宜可解决.
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