Question

I know this question is typique and it was asked many times in the forum, but I still cannot solve my problem, so please if any body can help be that would be GREAT 🙂

I am creating a book application in the arabic languages and I need to perform the transitions of the uipageviewcontroller from right to left. And thats all I have to say.

One more thing (if I hadn’t explain very well my self) I have the exact need as this thread: How to change UIPageViewController direction of paging curl animation but I couldn’t manage to make the solution they spoke about, so if someone can explain me or give me a link where I can have how to do it that would be more than enough 🙂

Answer 1

It can be done in this way

1. Swap the code of pageViewController’s datasource from viewControllerBeforeViewController to viewControllerAfterViewController

2. Change UIPageViewControllerSpineLocationMin to UIPageViewControllerSpineLocationMax

To check that, start Page-Based Application template as Universal and change the following in ModelController.m

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
    NSUInteger index = [self indexOfViewController:(DataViewController *)viewController];
    if (index == NSNotFound) {
        return nil;
    }

    index++;
    if (index == [self.pageData count]) {
        return nil;
    }
    return [self viewControllerAtIndex:index storyboard:viewController.storyboard];
}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController
{
    NSUInteger index = [self indexOfViewController:(DataViewController *)viewController];
    if ((index == 0) || (index == NSNotFound)) {
        return nil;
    }

    index--;
    return [self viewControllerAtIndex:index storyboard:viewController.storyboard];
}

and change UIPageViewControllerSpineLocationMin to UIPageViewControllerSpineLocationMax and swipe the condition of (indexOfCurrentViewController % 2 == 0) in “RootViewController.m”

- (UIPageViewControllerSpineLocation)pageViewController:(UIPageViewController *)pageViewController spineLocationForInterfaceOrientation:(UIInterfaceOrientation)orientation
{
    if (UIInterfaceOrientationIsPortrait(orientation) || ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone)) {
        UIViewController *currentViewController = [self.pageViewController.viewControllers objectAtIndex:0];
        NSArray *viewControllers = [NSArray arrayWithObject:currentViewController];
        [self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:NULL];

        self.pageViewController.doubleSided = NO;
        return UIPageViewControllerSpineLocationMax;
    }

    DataViewController *currentViewController = [self.pageViewController.viewControllers objectAtIndex:0];
    NSArray *viewControllers = nil;

    NSUInteger indexOfCurrentViewController = [self.modelController indexOfViewController:currentViewController];
    if (indexOfCurrentViewController == 0 || indexOfCurrentViewController % 2 == 0) {
        UIViewController *previousViewController = [self.modelController pageViewController:self.pageViewController viewControllerBeforeViewController:currentViewController];
        viewControllers = [NSArray arrayWithObjects:previousViewController, currentViewController, nil];
    } else {
        UIViewController *nextViewController = [self.modelController pageViewController:self.pageViewController viewControllerAfterViewController:currentViewController];
        viewControllers = [NSArray arrayWithObjects:currentViewController, nextViewController, nil];
    }
    [self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:NULL];


    return UIPageViewControllerSpineLocationMid;
}

Source: PageViewControllers Apple Doc