Changing UIPageViewController's page programmatically doesn't update the UIPageControl

Question

In my custom UIPageViewController class:

- (id)initWithCoder:(NSCoder *)aDecoder
{
    self = [super initWithCoder:aDecoder];
    if (self) {
           


        

Answer 1

// ViewController.h File

#import 
#import "PageContentViewController.h"

@interface ViewScreen : UIViewController

- (IBAction)Startwalkthrough:(id)sender;

@property(strong, nonatomic)UIPageViewController *pageViewController;
@property(strong, nonatomic)NSArray * pageTitles;
@property(strong,nonatomic)NSArray * pageImages;

@end

// ViewController.m File
#import "ViewScreen.h"

@interface ViewScreen ()

@end

@implementation ViewScreen

@synthesize pageTitles,pageImages;

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    pageTitles =@[@"dianna",@"images",@"image",@"i1",@"hulk1",@"assasins"];
    pageImages =@[@"dianna",@"images",@"image",@"i1",@"hulk1",@"assasins"];

    self.pageViewController =[self.storyboard instantiateViewControllerWithIdentifier:@"PageViewController"];
    self.pageViewController.dataSource=self;

    PageContentViewController *startingViewController = [self viewControllerAtIndex:0];

    NSArray * viewController =@[startingViewController];

    [self.pageViewController setViewControllers:viewController direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil];

    [self addChildViewController:_pageViewController];

    [self.view addSubview:_pageViewController.view];
    [self.pageViewController didMoveToParentViewController:self];


}

-(IBAction)Startwalkthrough:(id)sender
{
    PageContentViewController * startingViewController =[self viewControllerAtIndex:0];
    NSArray * viewControllers =@[startingViewController];
    [self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionReverse animated:NO completion:nil];

}

- (PageContentViewController *)viewControllerAtIndex:(NSUInteger)index
{
    if (([self.pageTitles count] == 0) || (index >= [self.pageTitles count])) {
        return nil;
    }

    // Create a new view controller and pass suitable data.
    PageContentViewController *pageContentViewController = [self.storyboard instantiateViewControllerWithIdentifier:@"PageContentViewController"];
    pageContentViewController.imageFile = self.pageImages[index];
    pageContentViewController.titletext = self.pageTitles[index];
    pageContentViewController.pageIndex = index;

    return pageContentViewController;
}


#pragma mark - Page View Controller Data Source

-(UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
    NSUInteger index =((PageContentViewController *) viewController).pageIndex;
    if (index == NSNotFound) {
        return nil;
    }

    index--;
    if (index ==[self.pageTitles count]) {
        return  nil;

}
    return [self viewControllerAtIndex:index];

}

- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController
{
    NSUInteger index = ((PageContentViewController*) viewController).pageIndex;

    if (index == NSNotFound) {
        return nil;
    }

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

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

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


// Second File

PageViewController.h File 
#import 

@interface PageContentViewController : UIViewController

@property (strong, nonatomic) IBOutlet UILabel *txtLabel;
@property (strong, nonatomic) IBOutlet UIImageView *backgroundImageView;

@property NSUInteger pageIndex;
@property  NSString *titletext;
@property NSString * imageFile;
@end


// SecondFile.M File
#import "PageContentViewController.h"

@interface PageContentViewController ()

@end

@implementation PageContentViewController



-(id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self =[super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        //
    }
    return  self;
}

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.

    self.backgroundImageView.image =[UIImage imageNamed:self.imageFile];
    self.txtLabel.text =self.titletext;

}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}


/*
#pragma mark - Navigation

// In a storyboard-based application, you will often want to do a little preparation before navigation
- (void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
    // Get the new view controller using [segue destinationViewController].
    // Pass the selected object to the new view controller.
}
*/

@end