在UIPageViewCotroller中检查后退/前进滚动时出现错误
在UIPageViewCotroller中检查后退/前进滚动时出现错误
提问于 2016-09-24 09:36:27
我正在尝试从一个数组中加载合适的图像到我的UIPageViewController的视图中，我有3个视图，为了防止崩溃，我循环浏览它们。
我会跟踪我是向前还是向后滚动，但有时当我非常快速地向前和向后翻转时，我会遇到一个bug，它会翻转方向，然后我会重复几次滚动，得到相同的视图。
下面是在滚动完成时更新局部变量index的函数
func pageViewController(pvc: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
if completed {
let thisPage = pvc.viewControllers!.last as! PageContentViewController
let currentIndex = thisPage.pageIndex
let lastIndex = lastPage.pageIndex
if(currentIndex > urlIndex){
urlIndex += 1
}else if(currentIndex < urlIndex) {
urlIndex -= 1
}else{
}
}
}下面是我的UIPageViewController代码的其余部分：
override func viewDidLoad() {
super.viewDidLoad()
dataSource = self
delegate = self
}
private(set) lazy var orderedViewControllers: [PageContentViewController] = {
return [self.newPageContentViewController(),
self.newPageContentViewController(),
self.newPageContentViewController()
]
}()
private func newPageContentViewController() -> PageContentViewController {
return UIStoryboard(name: "Main", bundle: nil) .
instantiateViewControllerWithIdentifier("PageContentViewController") as! PageContentViewController
}
private func getNextViewController() -> PageContentViewController{
let scrollView = orderedViewControllers.removeAtIndex(0)
orderedViewControllers.append(scrollView)
return scrollView
}
private func getPreviousViewController() -> PageContentViewController{
let scrollView = orderedViewControllers.removeLast()
orderedViewControllers.insert(scrollView, atIndex: 0)
return scrollView
}
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController?
{
guard urlIndex > 0 else {
return nil
}
let previousUrlIndex = urlIndex - 1
return getViewControllerAtIndex(previousUrlIndex, next: false)
}
func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController?
{
let nextUrlIndex = urlIndex + 1
guard arrayRouteName.count > nextUrlIndex else{
return nil
}
return getViewControllerAtIndex(nextUrlIndex, next: true)
}
func getViewControllerAtIndex(index: NSInteger, next: Bool) -> PageContentViewController
{
// Create a new view controller and pass suitable data.
var pageContentViewController:PageContentViewController
if(next){
pageContentViewController = getNextViewController()
}else{
pageContentViewController = getPreviousViewController()
}
pageContentViewController.localImage = arrayLocalImage[index]
pageContentViewController.pageIndex = index
pageContentViewController.view.clipsToBounds = true
return pageContentViewController
}回答 1
Stack Overflow用户
回答已采纳
发布于 2016-10-22 08:43:29
我已经设法解决了这个问题。我已经从UIPageControllerDelegate中删除了pageViewController函数，并简单地更改了数据源中的pageViewController函数，以从viewController获取索引，如下所示
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController?
{
let index = ((viewController as! UIPageContentViewController).pageIndex) - 1
guard index < 0 {
return nil
}
return getViewControllerAtIndex(index, pageContentViewController: getPreviousViewController() )
}它的行为就像它应该的那样。
页面原文内容由Stack Overflow提供。腾讯云小微IT领域专用引擎提供翻译支持
原文链接：
https://stackoverflow.com/questions/39671671
复制相关文章
相似问题
腾讯云开发者
