Question

我目前正在开发具有3个视图控制器的iOS应用，可通过左右滑动来访问它们。

我希望将“ WeatherVC”作为启动应用程序时显示的View Controller，而我正在努力解决这一问题。我还希望选项卡之间的特定顺序为：选项卡1 = ClimaVC-选项卡2 = WeatherVC-选项卡3 = ClosetVC。

到目前为止，这是我的代码，其中包含3个View Controller：

import UIKit

class PageViewController: UIPageViewController, 
UIPageViewControllerDelegate, UIPageViewControllerDataSource {

lazy var orderedViewControllers : [UIViewController] = {
return [self.newVC(viewController : "ClimaVC"),
        self.newVC(viewController : "WeatherVC"),
    self.newVC(viewController : "ClosetVC")]
}()



override func viewDidLoad() {
    super.viewDidLoad()

    // Do any additional setup after loading the view.

    self.dataSource = self



    //If let to check if firstViewController is not nil to use it.
                if let firstViewController = orderedViewControllers.first{
                    setViewControllers([firstViewController],
                                       direction: .forward, animated: true, completion: nil)

            }

    self.delegate = self
}


func newVC(viewController : String) -> UIViewController {

    return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: viewController)


}

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

    //Guard = some kind of if statement.
    guard let viewControllerIndex = orderedViewControllers.index(of: viewController) else {
        return nil
    }

    let previousIndex = viewControllerIndex - 1;

    guard previousIndex >= 0 else {
       // return orderedViewControllers.last
        //Return nil to avoid swiping forever.
        return nil
    }

    guard orderedViewControllers.count > previousIndex else {
        return nil
    }

    return orderedViewControllers[previousIndex]

}

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

    //Guard = some kind of if statement.
    guard let viewControllerIndex = orderedViewControllers.index(of: viewController) else {
        return nil
    }

    let nextIndex = viewControllerIndex + 1;

    guard orderedViewControllers.count != nextIndex else {
        //return orderedViewControllers.first
        //Return nil to avoid swiping forever.
        return nil
    }

    guard orderedViewControllers.count > nextIndex else {
        return nil
    }

    return orderedViewControllers[nextIndex]

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}

}

任何帮助将不胜感激，因为我无法弄清楚这一点，而且我花了很多时间尝试！

谢谢大家！

Answer 1

您可以尝试

setViewControllers([orderedViewControllers[1]],
                                   direction: .forward, animated: true, completion: nil)

Answer 2

为什么不尝试UICollectionView？ UIPageViewController存在一些问题，这种情况下不需要UIPageViewController

在PageViewController中打开特定的View Controller

2 个答案: