ios - 我的 UIPageViewController 不断崩溃

Question

我花了几个小时尝试使用仪器和 StackOverFlow 对此进行调试，但我还没有找到解决方案。我的UIPageViewController一直闪退，我真的认为是CPU快到100%，内存能到高位了。但是，我找不到任何变量或任何强引用来阻止以前未显示的 View Controller 解除分配。我认为这是 PageViewController 中的内存问题，但我不是 100% 确定。我是 Swift 的新手，我真的很难尝试首次亮相，所以非常感谢任何帮助。这是我的 UIPageViewControllerDataSource 的代码。

import UIKit

class HarishIntroduction: UIViewController, UIPageViewControllerDataSource {

var pageViewController: UIPageViewController!

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view.
    self.pageViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishPageViewController") as! UIPageViewController
    self.pageViewController.dataSource = self
    weak var initialViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishIntroduction") as? HarishIntroduction
    let viewController = NSArray(object: initialViewController!)
    dispatch_async(dispatch_get_main_queue(), {
        self.pageViewController.setViewControllers(viewController as? [UIViewController], direction: .Forward, animated: false, completion: nil)
    })
    self.pageViewController.view.frame = self.view.bounds
    self.addChildViewController(pageViewController)
    self.view.addSubview(self.pageViewController.view)
    self.pageViewController.didMoveToParentViewController(self)
}

func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
    if viewController.isKindOfClass(HarishIntroduction) {
        return nil
    }
    if viewController.isKindOfClass(HarishPlaces) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishIntroduction") as? HarishIntroduction
        return correctViewController
    }
    if viewController.isKindOfClass(WyomingSeminary) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishPlaces") as? HarishPlaces
        return correctViewController
    }
    if viewController.isKindOfClass(AppleTree) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("WyomingSeminary") as? WyomingSeminary
        return correctViewController
    }
    if viewController.isKindOfClass(KearneyHighSchool) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("AppleTree") as? AppleTree
        return correctViewController
    }
    if viewController.isKindOfClass(MosconeCenter) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("KearneyHighSchool") as? KearneyHighSchool
        return correctViewController
    }
    else {
        return nil
    }
}

func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
    if viewController.isKindOfClass(HarishIntroduction) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishPlaces") as? HarishPlaces
        return correctViewController
    }
    if viewController.isKindOfClass(HarishPlaces) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("WyomingSeminary") as? WyomingSeminary
        return correctViewController
    }
    if viewController.isKindOfClass(WyomingSeminary) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("AppleTree") as? AppleTree
        return correctViewController
    }
    if viewController.isKindOfClass(AppleTree) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("KearneyHighSchool") as? KearneyHighSchool
        return correctViewController
    }
    if viewController.isKindOfClass(KearneyHighSchool) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("MosconeCenter") as? MosconeCenter
        return correctViewController
    }
    if viewController.isKindOfClass(MosconeCenter) {
        return nil
    }
    else {
        return nil
    }
}

更新:初始 View Controller 是“HarishIntroduction”。

Answer 1

您所做的不是正确的方法，您正在尝试使用初始 View Controller 实例化 UIPageViewController 作为 View Controller ，而 View Controller 又是 UIPageViewController 的父级。

我在一个单独的类上执行此操作，一切正常，尽管在页面 Controller 层次结构中我只创建了两个 View Controller 。您可以添加更多，这没有问题。

并且不需要在 viewDidLoad 上的 main_queue 上执行dispatch_async，因为您已经在带有 viewDidLoad 的 main_queue 中，请删除该代码。

import UIKit

class ViewController: UIViewController, UIPageViewControllerDataSource {

var pageViewController: UIPageViewController!
var harishStoryboard:UIStoryboard!

override func viewDidLoad() {
    super.viewDidLoad()

    self.harishStoryboard = self.storyboard

    // Do any additional setup after loading the view.
    self.pageViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishPageViewController") as! UIPageViewController
    self.pageViewController.dataSource = self
    let initialViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishIntroduction") as! HarishIntroduction
    let viewController = NSArray(object: initialViewController)

    self.pageViewController.setViewControllers(viewController as? [UIViewController], direction: .Forward, animated: false, completion: nil)
    self.pageViewController.view.frame = self.view.bounds
    self.addChildViewController(pageViewController)
    self.view.addSubview(self.pageViewController.view)
    self.pageViewController.didMoveToParentViewController(self)
}

func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
    if viewController.isKindOfClass(HarishIntroduction) {
        return nil
    }
    if viewController.isKindOfClass(HarishPlaces) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishIntroduction") as? HarishIntroduction
        return correctViewController
    }
    /*if viewController.isKindOfClass(WyomingSeminary) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishPlaces") as? HarishPlaces
        return correctViewController
    }
    if viewController.isKindOfClass(AppleTree) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("WyomingSeminary") as? WyomingSeminary
        return correctViewController
    }
    if viewController.isKindOfClass(KearneyHighSchool) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("AppleTree") as? AppleTree
        return correctViewController
    }
    if viewController.isKindOfClass(MosconeCenter) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("KearneyHighSchool") as? KearneyHighSchool
        return correctViewController
    }*/
    else {
        return nil
    }
}

func pageViewController(pageViewController: UIPageViewController, viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
    if viewController.isKindOfClass(HarishIntroduction) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("HarishPlaces") as? HarishPlaces
        return correctViewController
    }
    /*if viewController.isKindOfClass(HarishPlaces) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("WyomingSeminary") as? WyomingSeminary
        return correctViewController
    }
    if viewController.isKindOfClass(WyomingSeminary) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("AppleTree") as? AppleTree
        return correctViewController
    }
    if viewController.isKindOfClass(AppleTree) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("KearneyHighSchool") as? KearneyHighSchool
        return correctViewController
    }
    if viewController.isKindOfClass(KearneyHighSchool) {
        let correctViewController = harishStoryboard.instantiateViewControllerWithIdentifier("MosconeCenter") as? MosconeCenter
        return correctViewController
    }
    if viewController.isKindOfClass(MosconeCenter) {
        return nil
    }*/
    else {
        return nil
    }
}
}

上面的代码对我来说效果很好，如果需要我可以为您上传项目。