Ios UIPageViewController点不显示

一切正常，但圆点不显示。我的代码是

import UIKit

class MyPageViewController: UIPageViewController  {

override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.

    dataSource = self

    if let firstViewController = orderedViewControllers.first {
        setViewControllers([firstViewController],
                           direction: .forward,
                           animated: true,
                           completion: nil)
    }

}

private(set) lazy var orderedViewControllers: [UIViewController] = {

    return [self.newColoredViewController(color: ""),
            self.newColoredViewController(color: "Second"),
            self.newColoredViewController(color: "Third")]
}()

private func newColoredViewController(color: String) -> UIViewController {

    return UIStoryboard(name: "Main", bundle: nil) .
        instantiateViewController(withIdentifier: "\(color)ViewController")
}

}


// MARK: UIPageViewControllerDataSource

extension MyPageViewController: UIPageViewControllerDataSource {

    func pageViewController(_ pageViewController: UIPageViewController, viewControllerBefore viewController: UIViewController) -> UIViewController? {

        guard let viewControllerIndex = orderedViewControllers.firstIndex(of: viewController) else {
            return nil
        }

        let previousIndex = viewControllerIndex - 1

        guard previousIndex >= 0 else {
            return nil
        }

        guard orderedViewControllers.count > previousIndex else {
            return nil
        }

        return orderedViewControllers[previousIndex]
    }

    func pageViewController(_ pageViewController: UIPageViewController,
                            viewControllerAfter viewController: UIViewController) -> UIViewController? {
        guard let viewControllerIndex = orderedViewControllers.firstIndex(of: viewController) else {
            return nil
        }

        let nextIndex = viewControllerIndex + 1
        let orderedViewControllersCount = orderedViewControllers.count

        guard orderedViewControllersCount != nextIndex else {
            return nil
        }

        guard orderedViewControllersCount > nextIndex else {
            return nil
        }

        return orderedViewControllers[nextIndex]
    }

    func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
        setupPageControl()
        return orderedViewControllers.count
    }

    func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
        return 0
    }

    private func setupPageControl() {
        let appearance = UIPageControl.appearance()
        appearance.pageIndicatorTintColor = UIColor.darkGray
        appearance.currentPageIndicatorTintColor = UIColor.red
        appearance.backgroundColor = UIColor.black
    }

}

---

您使用的这些函数的版本不正确

为了显示UIPageControl，您需要实现两个可选的数据源方法。只需返回presentationCount的完整页数和presentationIndex

func presentationCount(for pageViewController: UIPageViewController) -> Int {
    setupPageControl()
    return orderedViewControllers.count
    }

func presentationIndex(for pageViewController: UIPageViewController) -> Int {
    return 0
    }

---

您使用的这些函数的版本不正确

为了显示UIPageControl，您需要实现两个可选的数据源方法。只需返回presentationCount的完整页数和presentationIndex

func presentationCount(for pageViewController: UIPageViewController) -> Int {
    setupPageControl()
    return orderedViewControllers.count
    }

func presentationIndex(for pageViewController: UIPageViewController) -> Int {
    return 0
    }

---

您应该添加页面视图控制器数据源和页数：

---

pageControl.numberOfPages=3

您应该添加页面视图控制器数据源和页数：

---

---

pageControl.numberOfPages=3

您是否在故事板中使用

UIPageViewControllerTransitionStyleScroll

，请参阅我更新的问题此方法调用了

presentationCountForPageViewController

？没有调用…presentationCountForPageViewController在数据源中，因此它很好。如果您有教程中的复制粘贴代码，那么请确保它符合最新的swift语法。您是否在故事板中使用了

UIPageViewControllerTransitionStyleScroll

，我修复了它，请参阅我更新的问题此方法已调用？否未调用…presentationCountForPageViewController位于数据源中，因此可以。若你们有教程中的复制粘贴代码，那个么确保它符合最新的swift syntaxYes，它可以工作，但背景是黑色的。如何将UIPageControl backgroundColor设置为白色：UIPageControl.appearance（）.backgroundColor=UIColor.white@Hitesh Borse，谢谢，但它不能满足我的要求。请建议如何将PageViewController添加到exist ViewController并加载一个或三个ViewController。你能为我推荐一些代码或教程吗？谢谢，这段代码对我来说没什么变化，是的，它可以工作，但是背景颜色变黑了。如何将UIPageControl backgroundColor设置为白色：UIPageControl.appearance（）.backgroundColor=UIColor.white@Hitesh Borse，谢谢，但它不能满足我的要求。请建议如何将PageViewController添加到exist ViewController并加载一个或三个ViewController。你能为我推荐一些代码或教程吗？谢谢，这些代码对我来说很有用，只做了一些改动，