olxios

@implementation ViewController

#pragma mark View Lifecycle

- (void)viewDidLoad
{
    [super viewDidLoad];
    [self createPageViewController];
    [self setupPageControl];
}

olxios

// MARK: - View Lifecycle
    override func viewDidLoad() {
        super.viewDidLoad()
        createPageViewController()
        setupPageControl()
    }
    
    private func createPageViewController() {
        
        let pageController = self.storyboard!.instantiateViewControllerWithIdentifier("PageController") as! UIPageViewController

olxios

#pragma mark UIPageViewControllerDataSource

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
    PageItemController *itemController = (PageItemController *)viewController;
    
    if (itemController.itemIndex > 0)
    {
        return [self itemControllerForIndex:itemController.itemIndex-1];
    }

olxios

// MARK: - UIPageViewControllerDataSource
    
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
        
    let itemController = viewController as! PageItemController
        
    if itemController.itemIndex > 0 {
       return getItemController(itemController.itemIndex-1)
    }
        

olxios

#pragma mark Page Indicator

- (NSInteger)presentationCountForPageViewController:(UIPageViewController *)pageViewController
{
    return [_contentImages count];
}

- (NSInteger)presentationIndexForPageViewController:(UIPageViewController *)pageViewController
{
    return 0;

olxios

// MARK: - Page Indicator
    
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
    return contentImages.count
}
    
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
    return 0
}

olxios

- (UIViewController *)currentController
{
    if ([self.pageViewController.viewControllers count])
    {
        return self.pageViewController.viewControllers[0];
    }
    
    return nil;
}

olxios

func currentController() -> UIViewController? {
        
        if self.pageViewController?.viewControllers?.count > 0 {
            return self.pageViewController?.viewControllers![0]
        }
        
        return nil
}

olxios

func currentControllerIndex() -> Int {
        
        let pageItemController = self.currentController()
        
        if let controller = pageItemController as? PageItemController {
            return controller.itemIndex
        }
        
        return -1
}

olxios

- (NSUInteger)currentControllerIndex
{
    PageItemController *pageItemController = (PageItemController *) [self currentController];
    
    if (pageItemController)
    {
        return pageItemController.itemIndex;
    }
    
    return -1;