Simple implementation for swipe-to-back/forward UINavigationController

SwipeNavigationController.h

#import <UIKit/UIKit.h>


@interface SwipeNavigationController : UINavigationController <UIGestureRecognizerDelegate>

@property (nonatomic, readonly) NSArray *poppedViewControllers;

- (void)clearPoppedViewControllers;

@property (nonatomic, readonly) UISwipeGestureRecognizer *leftSwipeGestureRecognizer;
@property (nonatomic, readonly) UISwipeGestureRecognizer *rightSwipeGestureRecognizer;

- (void)handleLeftSwipeGesture:(UISwipeGestureRecognizer *)gestureRecognizer;
- (void)handleRightSwipeGesture:(UISwipeGestureRecognizer *)gestureRecognizer;

@end

SwipeNavigationController.m

#import "SwipeNavigationController.h"


@implementation SwipeNavigationController {
    NSMutableArray *_poppedViewControllers;
}

#pragma mark UIViewController

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil
{
    self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil];
    if (self) {
        _swipeNavigationEnabled = YES;
        _poppedViewControllers = [NSMutableArray new];
    }
    return self;
}

- (void)awakeFromNib
{
    _swipeNavigationEnabled = YES;
    _poppedViewControllers = [NSMutableArray new];
}

- (void)viewDidLoad
{
    [super viewDidLoad];
    {
        UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleLeftSwipeGesture:)];
        recognizer.direction = UISwipeGestureRecognizerDirectionLeft;
        recognizer.delegate = self;
        [self.view addGestureRecognizer:recognizer];
        _leftSwipeGestureRecognizer = recognizer;
    }{
        UISwipeGestureRecognizer *recognizer = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(handleRightSwipeGesture:)];
        recognizer.direction = UISwipeGestureRecognizerDirectionRight;
        recognizer.delegate = self;
        [self.view addGestureRecognizer:recognizer];
        _rightSwipeGestureRecognizer = recognizer;
    }
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    [self clearPoppedViewControllers];
}


#pragma mark UINavigationController

- (void)pushViewController:(UIViewController *)viewController animated:(BOOL)animated
{
    if ([self.poppedViewControllers count] > 0) {
        if (viewController == [self.poppedViewControllers lastObject]) {
            [_poppedViewControllers removeLastObject];
        } else {
            [_poppedViewControllers removeAllObjects];
        }
    }
    [super pushViewController:viewController animated:animated];
}

- (UIViewController *)popViewControllerAnimated:(BOOL)animated
{
    UIViewController *controller = [super popViewControllerAnimated:animated];
    [_poppedViewControllers addObject:controller];
    return controller;
}


#pragma mark UIGestureRecognizerDelegate

- (BOOL)gestureRecognizerShouldBegin:(UIGestureRecognizer *)gestureRecognizer
{
    if (!self.swipeNavigationEnabled) {
        return NO;
    } else if (gestureRecognizer == self.leftSwipeGestureRecognizer) {
        return ([self.poppedViewControllers count] > 0);
    } else if (gestureRecognizer == self.rightSwipeGestureRecognizer) {
        return ([self.viewControllers count] > 1);
    }
    return YES;
}


#pragma mark SwipeNavigationController

- (void)clearPoppedViewControllers
{
    [_poppedViewControllers removeAllObjects];
}

- (void)handleLeftSwipeGesture:(UISwipeGestureRecognizer *)gestureRecognizer
{
    if (gestureRecognizer.state == UIGestureRecognizerStateRecognized
        && self.swipeNavigationEnabled
        && self.visibleViewController
        && ![self.visibleViewController isBeingPresented]
        && ![self.visibleViewController isBeingDismissed]) {
        [self pushViewController:[self.poppedViewControllers lastObject] animated:YES];
    }
}

- (void)handleRightSwipeGesture:(UISwipeGestureRecognizer *)gestureRecognizer
{
    if (gestureRecognizer.state == UIGestureRecognizerStateRecognized
        && self.swipeNavigationEnabled
        && self.visibleViewController
        && ![self.visibleViewController isBeingPresented]
        && ![self.visibleViewController isBeingDismissed]) {
        [self popViewControllerAnimated:YES];
    }
}

@end