Preventing the white gap that appears on swiping U

Question

I have implemented the UIPageViewController in this manner:

GalleryViewController: is the container of the PageViewController

PageViewController: is the pageViewController which I added it to GalleryViewController as a subview.

PageContentViewController: I put in it UIImageView to be the content of the page view controller.

Everything is going well, but when I swipe between images, weird things happen. There is white gap appears upside.

The weird thing is when I finish scrolling it stretches automatically.

This is the code of GalleryViewController, which is the container of the PageViewController:

import UIKit

class PageViewController: UIViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate {

var startIndex:Int = 0

var pageViewController : UIPageViewController!

override func viewDidLoad() {
    self.navigationController?.hidesBarsOnTap = true;
    reset()
}

func reset() {
    /* Getting the page View controller */
    pageViewController = self.storyboard?.instantiateViewControllerWithIdentifier("PageViewController") as UIPageViewController
    self.pageViewController.dataSource = self

    let pageContentViewController = self.viewControllerAtIndex(0)
    self.pageViewController.setViewControllers([pageContentViewController!], direction: UIPageViewControllerNavigationDirection.Forward, animated: true, completion: nil)

    self.pageViewController.view.frame = CGRectMake(0, 0, self.view.frame.width, self.view.frame.height)
    self.addChildViewController(pageViewController)
    self.view.addSubview(pageViewController.view)
    self.pageViewController.didMoveToParentViewController(self)
    println("\(startIndex) start index")
}


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

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

    var index = (viewController as PageContentViewController).pageIndex!
    index++
    if(index >= Constants.Statics.images.count){
        return nil
    }
    return self.viewControllerAtIndex(index)

}

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

    var index = (viewController as PageContentViewController).pageIndex!
    if(index <= 0){
        return nil
    }
    index--
    return self.viewControllerAtIndex(index)

}

func viewControllerAtIndex(index : Int) -> UIViewController? {
    if((Constants.Statics.images.count == 0) || (index >= Constants.Statics.images.count)) {
        return nil
    }
    let pageContentViewController = self.storyboard?.instantiateViewControllerWithIdentifier("PageContentViewController") as PageContentViewController
    pageContentViewController.pageIndex = index
    return pageContentViewController
}

}

What can I do to prevent that stretching and the white gap on swiping?

UPDATED:

A strange thing has happened, I changed the pageViewController Transition Style to Page Curl, the problem did not appear. Sounds like it is about scrolling!

Answer 1

Have you tried those? You should select your content view controller first. Note: click on the controller, not the view

1. uncheck Adjust Scroll View Insets
2. uncheck Under Top Bars
3. uncheck Under Bottom Bars