在 UIWebView 中向上/向下滑动手势不起作用

Question

我在 UIViewController 中托管了一个 UIWebView， 我设法通过以下方式添加右/左手势：

var swipeRight = UISwipeGestureRecognizer(target: self, action: "swiped:")
swipeRight.direction = UISwipeGestureRecognizerDirection.Right
self.webView.addGestureRecognizer(swipeRight)

它不适用于上/下方向的问题：

var swipeDown = UISwipeGestureRecognizer(target: self, action: "swiped:")
swipeDown.direction = UISwipeGestureRecognizerDirection.Down
self.webView.addGestureRecognizer(swipeDown)

我认为这是因为滚动，我也尝试将其添加到滚动视图中，但它仍然无法识别上/下手势：

self.webView.scrollView.addGestureRecognizer(swipeDown)

更新：
我尝试了 Harry 的回答，但它覆盖了向上/向下滑动的默认操作，我无法滚动页面：

self.view.addGestureRecognizer(swipeUp)
self.view.addGestureRecognizer(swipeDown)

self.webView.scrollView.panGestureRecognizer.requireGestureRecognizerToFail(swipeUp)
self.webView.scrollView.panGestureRecognizer.requireGestureRecognizerToFail(swipeDown)

Answer 1

将手势识别器添加到 self.view 而不是 UIWebView 实例。

self.view.addGestureRecognizer(swipeUp)
self.view.addGestureRecognizer(swipeDown)

在将向上/向下手势识别器添加到 Web 视图后添加这两行。

self.webView.scrollView.panGestureRecognizer.requireGestureRecognizerToFail(swipeUp)
self.webView.scrollView.panGestureRecognizer.requireGestureRecognizerToFail(swipeDown)

Answer 2

如果有人还在研究它，这解决了我的问题：

webView.scrollView.panGestureRecognizer.cancelsTouchesInView = NO;

upGesture.direction = UISwipeGestureRecognizerDirectionUp;
upGesture.cancelsTouchesInView = NO;
upGesture.delegate = self;
[webView.scrollView addGestureRecognizer:upGesture];

downGesture.direction = UISwipeGestureRecognizerDirectionDown;
downGesture.cancelsTouchesInView = NO;
downGesture.delegate = self;
[webView.scrollView addGestureRecognizer:downGesture];



- (BOOL)gestureRecognizer:(UIGestureRecognizer *)gestureRecognizer shouldRecognizeSimultaneouslyWithGestureRecognizer:(UIGestureRecognizer *)otherGestureRecognizer {
    return [gestureRecognizer isKindOfClass:[UISwipeGestureRecognizer class]] && [otherGestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]];
}