iphone - 是否可以同时使用 UIPanGesture 和 UISwipeGesture？

Question

我有一个 UIIMageView 子类，并且添加了 UIPanGestureRecognizer 和 UISwipeGestureRecognizer，如下所示:

self.userInteractionEnabled = YES;

UIPanGestureRecognizer * panGesture = [[UIPanGestureRecognizer alloc]initWithTarget:self action:@selector(handlePan:)];
[self addGestureRecognizer:panGesture];

UISwipeGestureRecognizer * swipeUp = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipeUp:)];
swipeUp.direction = UISwipeGestureRecognizerDirectionUp;
[self addGestureRecognizer:swipeUp];

UISwipeGestureRecognizer * swipeDown = [[UISwipeGestureRecognizer alloc]initWithTarget:self action:@selector(handleSwipeDown:)];
swipeDown.direction = UISwipeGestureRecognizerDirectionDown;
[self addGestureRecognizer:swipeDown];

但是当我向上或向下滑动时，我的选择器不会被调用，但平移总是会被调用。

任何澄清都会有帮助。

谢谢

Answer 1

问题是滑动手势也会被识别为 panGesture。

您需要做的是将委托(delegate)设置为实现该方法的类:

- (BOOL) gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
    return YES;
}

这将允许您同时识别两个手势，但需要清楚的是，当您的滑动被调用时，您的平移也会被调用。

From apple documentation :

This method is called when recognition of a gesture by either gestureRecognizer or otherGestureRecognizer would block the other gesture recognizer from recognizing its gesture. Note that returning YES is guaranteed to allow simultaneous recognition; returning NO, on the other hand, is not guaranteed to prevent simultaneous recognition because the other gesture recognizer's delegate may return YES.