UIPageViewController setViewController causing app to crash - ios

Question

I have a - (void)setViewControllers:(NSArray *)viewControllers direction:(UIPageViewControllerNavigationDirection)direction animated:(BOOL)animated completion:(void (^)(BOOL finished))completion set up in a method. Whenever the method is called it doesn't go to the next page. Instead, it goes to the UIPageViewController storyboard and then crashes. I'm not sure what I'm doing wrong. I am using MSPageViewController for the pageviewcontroller, could that be it?
Heres my code:
UIViewController *viewcont = [[UIViewController alloc]init];
NSArray *viewControllers = [NSArray arrayWithObject:viewcont];
[self setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];
Thanks.
There are 3 storyboards all conforming to MSPageViewControllerChild with the pageIndex property synthesized. IntroPageViewController is the first storyboard (p1).
PagingViewController.h:
//
// PagingViewController.m
// MordechaiLevi
//
// Created by Mordechai Levi on 4/10/14.
// Copyright (c) 2014 Mordechai Levi. All rights reserved.
//
#import "PagingViewController.h"
#import "IntroPageViewController.h"
#import "MSPageViewController.h"
#interface PagingViewController ()
#end
#implementation PagingViewController
- (void)viewDidLoad
{
[super viewDidLoad];
self.device = [UIDevice currentDevice];
self.device.proximityMonitoringEnabled = YES;
if (self.device.proximityMonitoringEnabled == YES) {
[[NSNotificationCenter defaultCenter] addObserver:self selector:#selector(sensorCovered) name:#"UIDeviceProximityStateDidChangeNotification" object:nil];
}else{
UIAlertView *alert = [[UIAlertView alloc]initWithTitle:#"Uh Oh!" message:#"To use this app you need a device with a proximity sensor." delegate:self cancelButtonTitle:#"Got it" otherButtonTitles:nil, nil];
[alert show];
}
self.view.backgroundColor = [UIColor colorWithRed:0.2 green:0.859 blue:0.643 alpha:1.0];
}
- (UIStatusBarStyle)preferredStatusBarStyle {
return UIStatusBarStyleLightContent;
}
- (void)sensorCovered {
if (self.device.proximityState == YES) {
IntroPageViewController *viewcont = [[IntroPageViewController alloc]init];
NSArray *viewControllers = [NSArray arrayWithObject:viewcont];
[self setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];
NSLog(#"sensor covered");
}else{
NSLog(#"sensor not covered");
}
}
- (NSArray *)pageIdentifiers {
return #[#"p1", #"p2", #"p3"];
}
#end

Answer 1

Looks like you're using MSPageViewController, with a controller that doesn't conform to MSPageViewControllerChild.
From the documentation:
Each of them [controllers] must be a class that conforms to MSPageViewControllerChild (if you don't need to add any extra functionality to it you can use MSPageViewControllerPage).