当方向设置为水平时，UIPageViewController 响应垂直平移

Question

我已经在这上面花了几个小时了。我已使用 UIPageViewControllerNavigationOrientationHorizo​​ntal 初始化了 UIPageViewController，但由于某种原因，当用户垂直平移时会调用 viewControllerBeforeViewController。

此外，当发生这种情况时，不会发生页面翻转，并且根本不会调用 didFinishAnimating:didFinishAnimating:previousViewControllers:transitionCompleted 。这意味着页面 View Controller 知道这是垂直移动。

这是初始化代码-

- (void)initPageViewController
{
    self.pageViewController = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStylePageCurl
                                                              navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal 
                                                                            options:nil];
    self.pageViewController.delegate = self;
    self.pageViewController.dataSource = self;

    [self addChildViewController:self.pageViewController];
    [self.view addSubview:self.pageViewController.view];

    // Set the page view controller's bounds using an inset rect so that self's view is visible around the edges of the pages.
    self.pageViewController.view.frame = self.view.bounds;

    [self.pageViewController didMoveToParentViewController:self];

    // Leave only pan recognizers enabled, so buttons positioned inside a page would work.
    for (UIGestureRecognizer *gr in self.pageViewController.gestureRecognizers)
    {
        if ([gr class] != [UIPanGestureRecognizer class])
            gr.enabled = NO;
    }
}

有什么想法吗？

Answer 1

我最初偶然发现您面临同样的问题 - 但我似乎已经针对我的情况修复了它。

基本上，我要做的就是为附加到 UIPageViewController 的所有手势识别器设置一个委托(delegate)。因此，在创建 UIPageViewController 后不久，我做了:

for (UIGestureRecognizer *gr in self.book.gestureRecognizers)
    gr.delegate = self.book;

其中 book 是我的自定义 UIPageViewController (我基本上将自己设置为委托(delegate))。最后，将此方法添加到您的 UIPageViewController 中以限制任何垂直平移(或使用注释掉的行来限制水平平移)。

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    if ([gestureRecognizer isKindOfClass:[UIPanGestureRecognizer class]])
    {
        UIPanGestureRecognizer *panGestureRecognizer = (UIPanGestureRecognizer *)gestureRecognizer;
        CGPoint translation = [panGestureRecognizer translationInView:self.view];

        return fabs(translation.x) > fabs(translation.y);
//      return fabs(translation.y) > fabs(translation.x);
    }
    else
        return YES;
}

感谢this answer向我暗示了这一点- 只需确保仅过滤掉 UIPanGestureRecognizer。