- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions

{

    self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];

    // Override point for customization after application launch.

    RootViewController *rootViewController = [[[RootViewController alloc] init] autorelease];

    DYNavigationController *navigationController = [[[DYNavigationController alloc]

            initWithRootViewController:rootViewController] autorelease];

    self.window.rootViewController = navigationController;

    [self.window makeKeyAndVisible];

    return YES;

}

- (void)setUpGestureRecognizers:(UIViewController *)viewController {

    // Swipe right: pop the current view and go back one level

    UISwipeGestureRecognizer *rightSwipeGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(popCurrentViewOut:)];

    rightSwipeGesture.direction = UISwipeGestureRecognizerDirectionRight;

    [viewController.view addGestureRecognizer:rightSwipeGesture];

    [rightSwipeGesture release];

    // Swipe left: push a new view

    UISwipeGestureRecognizer *leftSwipeGesture = [[UISwipeGestureRecognizer alloc] initWithTarget:self action:@selector(pushNewViewIn:)];

    leftSwipeGesture.direction = UISwipeGestureRecognizerDirectionLeft;

    [viewController.view addGestureRecognizer:leftSwipeGesture];

    [leftSwipeGesture release];

}

- (void)pushViewController:(UIViewController *)viewController {

    // Place the new view to the right next to the current view

    viewController.view.frame = CGRectOffset(self.view.bounds, self.view.bounds.size.width, );

    // Add the new view to our view hierarchy so that it displays on screen.

    [self.view addSubview:viewController.view];

    // Start animation

    [UIView animateWithDuration:ANIMATION_DURATION delay:ANIMATION_DELAY options:UIViewAnimationCurveEaseInOut animations:^{

        [self currentViewController].view.frame = CGRectOffset(self.view.bounds, -self.view.bounds.size.width, );

        viewController.view.frame = self.view.bounds;

    }   completion:^(BOOL finished) {

        if (finished) {

            // Connect DYNavigationController to viewController if needed

            [self setNavigatorIfNeeded:viewController];

            // Set up gesture recognizer so that we can respond to swipes

            [self setUpGestureRecognizers:viewController];

            // Add the new controller to our viewControllerStack

            [self.viewControllerStack addObject:viewController];

        }

    }];

}

- (void)popViewController {

    // Sanity check - We only pop when there are at least two viewControllers in the stack,

    // otherwise there is nothing to pop

    if (self.viewControllerStack.count < ) return;

    // Start animation

    [UIView animateWithDuration:ANIMATION_DURATION delay:ANIMATION_DELAY options:UIViewAnimationCurveEaseInOut animations:^{

        [self currentViewController].view.frame = CGRectOffset(self.view.bounds, self.view.bounds.size.width, );

        [self previousViewController].view.frame = self.view.bounds;

    } completion:^(BOOL finished) {

        if (finished) {

            // Tear down gesture recognizers

            [self tearDownGestureRecognizers:[self currentViewController]];

            // Remove current viewController.view from self.

            [[self currentViewController].view removeFromSuperview];

            // Remove current viewController from self.

            [[self currentViewController] removeFromParentViewController];

            // Remove current view controller from viewControllerStack

            [self.viewControllerStack removeLastObject];

        }

    }];

}