UIPageViewController 定义与以前的值冲突

Question

我的应用使用 UIPageViewController。当我输入以下两个函数

   func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
        return nil
    }

    func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
        return nil
    }

需要这些函数才能摆脱 "does not conform to UIPageViewControllerDataSource"

完整代码为：

import UIKit

class Root: UIPageViewController, UIPageViewControllerDataSource  {

    override func viewDidLoad() {
        super.viewDidLoad()

        self.dataSource = self
    }

    func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
        return nil
    }

    func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
        return nil
    }
}

Answer 1

尝试从 viewDidLoad 中删除函数并将它们放入 class 正文:)。

import UIKit

class Root: UIPageViewController, UIPageViewControllerDataSource  {
    override func viewDidLoad() {
        super.viewDidLoad()

        self.dataSource = self
    }

    func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
        return nil
    }

    func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
        return nil
    }
}

UIPageViewController 定义与以前的值冲突

UIPageViewController Definition conflicts with previous value

ios

uipageviewcontroller

swift

swift2