1.导航控制器-父级
1.页面视图控制器-导航控制器的子级

1. DetailsViewController -要在页面视图控制器中显示视图控制器
   我的DetailsViewController包含scrollview和detailsViewController的数组，其中不同的数据被传递给pageviewcontroller。
   问题是只有pageviewcontroller的第一个viewController显示在navigationbar下，并且其scrollview工作正常。
   但其余部分被推到导航控制器下，滚动视图不工作。

第1张图：第一个详细信息视图控制器工作正常
第二张图片：当我滑动时，数据集中的下一个DetailsViewController。这里的内容被推到导航栏下，滚动视图不工作
经过进一步的研究，我发现除了第一个细节视图控制器之外，其余的细节视图控制器的导航控制器属性都是空的。

//
//  PagerViewController.swift
//  
//
//  Created by Admin on 13/07/16.
// 
//

import UIKit

class PagerViewController: UIPageViewController {

    var result =  Array<SearchResult>();
    var mainStoryBoard  = UIStoryboard(name: "Main", bundle: nil);
    var resultSet = [UIViewController]();
    var currentIndex = 0;
    // MARK: - Life cycle Methods
    override func viewDidLoad() {
        super.viewDidLoad();
        dataSource = self;
        delegate = self;
        generateDatset();
        let initialViewController  = resultSet[currentIndex] ;
        let viewControllers = NSArray(objects : initialViewController);
        setViewControllers(viewControllers as? [UIViewController], direction: .Forward, animated: true, completion: nil);
        self.navigationController!.edgesForExtendedLayout = .None;
    }

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

    // MARK: - Dataset Initialisation

    func generateDatset()  {

        for searchResult in result {
            let viewController  = mainStoryBoard.instantiateViewControllerWithIdentifier(Constants.STORYBOARDUIFIELDS.DETAILSVIEWCONTROLLER) as? DetailsViewController;

            viewController?.searchResult =  searchResult;
            resultSet.append(viewController!)
        }

    }

}

// MARK: - UIPageViewControllerDataSource

extension PagerViewController : UIPageViewControllerDataSource {

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

        guard let viewControllerIndex  = resultSet.indexOf(viewController)  else {
            return nil;
        }

        let nextIndex  = viewControllerIndex + 1;

        guard  resultSet.count > nextIndex else {
                       return nil;
        }

        currentIndex = nextIndex;
        return resultSet[nextIndex];

    }

    func scrollToNext(viewControllers : UIViewController) {
        setViewControllers([viewControllers], direction: .Forward, animated: true, completion: nil)
    }

    func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
       guard let viewControllerIndex = resultSet.indexOf(viewController) else {
            return nil;
        }
        let previousIndex =  viewControllerIndex - 1;

        guard previousIndex >= 0  else {
            return nil;
        }
        currentIndex  = previousIndex;
        return resultSet[previousIndex];

    }

}

 //
//  DetailsViewController.swift
//
//
//  Created by Admin on 13/07/16.
//  
//

import UIKit

class DetailsViewController: UIViewController {

    var searchResult  : SearchResult? = nil;

    @IBOutlet weak var ShoeImageView: UIImageView!

    @IBOutlet weak var DnsItemCodeLabel: UILabel!

    @IBOutlet weak var GeneralDetailsCollView: UICollectionView!

    override func viewDidLoad() {
        super.viewDidLoad()

        //print(navigationController)

        DnsItemCodeLabel.text = "\(searchResult!.DNS!) - \(searchResult!.ItemCode!)";

        // converting base64encoded image into nsdata and then to ui image

        let image = UIImage(data: NSData(base64EncodedString: searchResult!.Image!, options: NSDataBase64DecodingOptions.IgnoreUnknownCharacters)!)

        ShoeImageView.image = image;

        // Assigning source to CollectionView

        GeneralDetailsCollView.dataSource = self;
        print(navigationController)

    }

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

}

// MARK: - UICollectionViewDataSource

extension DetailsViewController : UICollectionViewDataSource  {

    // returns the number of items

    func collectionView(collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return (searchResult!.summaryItems?.count)!;
    }

    //return the cell for given position

    func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
          let cell = collectionView.dequeueReusableCellWithReuseIdentifier(Constants.STORYBOARDUIFIELDS.GENRAL_DETAILS_CELL, forIndexPath: indexPath) as! GeneralDetailsCell
        if let data = searchResult?.summaryItems![indexPath.row] {
            cell.TitleLable.text =  data.Title!;
            cell.ValueLabel.text  = data.Value!;
        }

        return cell

    }

}