【发布时间】：2019-09-24 14:49:34
【问题描述】：
没有从 ViewDidLoad 调用 UIPageViewControllerDataSource，因此只显示第一页并且滑动没有任何作用。
我已按照本教程进行操作：
https://spin.atomicobject.com/2015/12/23/swift-uipageviewcontroller-tutorial/
类似问题的答案不起作用。我查看了 5 个类似的问题，但没有一个对我有用。
class SetupViewController: UIPageViewController {
private(set) lazy var pages : [UIViewController] = {
return [self.newPage(1), self.newPage(2), self.newPage(3), self.newPage(4)]
}()
private func newPage(_ page: Int) -> UIViewController {
return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "Page\(page)")
}
override func viewDidLoad() {
super.viewDidLoad()
dataSource = self
if let firstPage = pages.first {
print(#function, "if let firstPage", firstPage, pages) //viewDidLoad() if let firstPage page1name [page1, page2, page3, page4]
setViewControllers([firstPage], direction: .forward, animated: true, completion: nil)
}
}
}
extension SetupViewController: UIPageViewControllerDataSource {
func pageViewController(_ pageViewController: UIPageViewController, viewControllerAfter viewController: UIViewController) -> UIViewController? {
print(#function) //It doesn't print
guard let pageIndex = pages.firstIndex(of: viewController) else { return nil }
let nextIndex = pageIndex + 1
let pageCount = pages.count
guard nextIndex != pageCount else { return nil }
guard pageCount > nextIndex else { return nil }
return pages[nextIndex]
}
func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? {
print(#function) //It doesn't print
guard let pageIndex = pages.firstIndex(of: viewController) else { return nil }
let previousIndex = pageIndex - 1
guard previousIndex >= 0 else { return nil }
guard pages.count > previousIndex else { return nil }
return pages[previousIndex]
}
}
故事板 ID 为：Page1、Page2、Page3 和 Page4
我做错了什么？
【问题讨论】：
标签： ios swift uipageviewcontroller uipagecontrol