swift - UIPageViewController多次加载ChildViews

Question

我已经对 UIPageViewController 进行了子类化，并且它工作正常。除了来回加载页面的新实例这一事实之外，而不是(如我所期望的那样)检索之前加载的实例。引用不是应该很强吗？

以下是我的代码。

感谢您的帮助。

皮里克

class CustomPageViewController: UIPageViewController, UIPageViewControllerDataSource {

var view1: FirstCustomViewController!
var view2: SecondCustomViewController!
var view3: ThirdCustomViewController!
var views = []

override func viewDidLoad() {
    super.viewDidLoad()

    self.dataSource = self;

    self.view1 = FirstViewController()
    self.view2 = SecondViewController()
    self.view3 = ThirdViewController()

    self.views = [self.view1, self.view2, self.view3]
    self.setViewControllers([self.view1], direction: UIPageViewControllerNavigationDirection.Forward, animated: true, completion: nil)
}

// MARK: - PageViewControllerDataSource

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

    let index = self.views.indexOfObject(viewController)

    if (index > 0) {
        return self.views.objectAtIndex(index-1) as? UIViewController
    }

    return nil
}

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

    let index = self.views.indexOfObject(viewController)

    if (index < self.views.count-1) {
        return self.views.objectAtIndex(index+1) as? UIViewController
    }

    return nil
}
}

Answer 1

似乎有问题的函数在 FirstViewController、SecondViewController、ThirdViewController 中。当我写下我的问题时， View Controller 按照“viewWillAppear”方法加载 View 。当我将代码移至“viewDidLoad”时， View 多次停止加载。