iOS: UIPageViewController - Use button to jump to next page - ios

Question

I have a series of VCs in a PageViewController that a user navigates left to right through with their fingers. I need to add in buttons that essentially perform the same action as the finger swiping, moving left or right by one through the VCs . How can I do this? Right now I am using these two methods to dynamically setting the VCs as the user swipes:
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController;
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController;
Is there someway I can do the same thing if a user clicks a button?

Answer 1

You can programmatically set the currently displayed view controller with a transition animation using setViewControllers:direction:animated:completion: on your page view controller.
Here is an example that presents view controllers with random background colors. You can adjust this to use your specific view controllers.
- (void)viewDidLoad
{
[super viewDidLoad];
self.pvc = [[UIPageViewController alloc] initWithTransitionStyle:UIPageViewControllerTransitionStyleScroll navigationOrientation:UIPageViewControllerNavigationOrientationHorizontal options:nil];
self.pvc.view.frame = CGRectInset(self.view.bounds, 200, 200);
[self.view addSubview:self.pvc.view];
[self.pvc setViewControllers:#[[self randomVC]] direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];
}
-(UIViewController*)randomVC
{
UIViewController *vc = [[UIViewController alloc] init];
UIColor *color = [UIColor colorWithRed:arc4random_uniform(255)/255.0 green:arc4random_uniform(255)/255.0 blue:arc4random_uniform(255)/255.0 alpha:1];
vc.view.backgroundColor = color;
return vc;
}
- (IBAction)previousButtonPressed:(id)sender {
[self.pvc setViewControllers:#[[self randomVC]] direction:UIPageViewControllerNavigationDirectionReverse animated:YES completion:nil];
}
- (IBAction)nextButtonPressed:(id)sender {
[self.pvc setViewControllers:#[[self randomVC]] direction:UIPageViewControllerNavigationDirectionForward animated:YES completion:nil];
}

Answer 2

In case Pages can be navigated by added button (Previous, Next) & also by swipe with page control ON.
Please go through below:
//Set Delegate & Data Source for PageView controller [Say in View Did Load]
self.pageViewController.dataSource = self;
self.pageViewController.delegate = self;
// PageBefore & After When User Scroll to move next or previous page
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerBeforeViewController:(UIViewController *)viewController
{
[_nextBtn setTitle:#"Next" forState:UIControlStateNormal];
NSUInteger index = ((PageContentViewController*) viewController).pageIndex;
if (index == NSNotFound)
{
return nil;
}
if (index > 0)
{
index--;
}
else
{
return nil;
}
return [self viewControllerAtIndex:index];
}
- (UIViewController *)pageViewController:(UIPageViewController *)pageViewController viewControllerAfterViewController:(UIViewController *)viewController{
NSUInteger index = ((PageContentViewController*) viewController).pageIndex;
if (index == NSNotFound) {
return nil;
}
if (index < 3)
{
index++;
}else
{
return nil;
}
return [self viewControllerAtIndex:index];}
//To Match Exact Index page view when scrolled & navigated using button action. Place button index when page is been translated.
- (void)pageViewController:(UIPageViewController *)pageViewController willTransitionToViewControllers:(NSArray *)pendingViewControllers{
buttonIndex = (int)((PageContentViewController*) pendingViewControllers.firstObject).pageIndex;}
-(void)pageViewController:(UIPageViewController *)pageViewController didFinishAnimating:(BOOL)finished previousViewControllers:(NSArray *)previousViewControllers transitionCompleted:(BOOL)completed{
if (buttonIndex == 0)
{
_backButton.hidden = true;
}else if (buttonIndex == [self.pageImages count] - 1)
{
_backButton.hidden = false;
[_nextBtn setTitle:#"Begin" forState:UIControlStateNormal];
}else
{
_backButton.hidden = false;
}
}
//Previous , Next Button Actions
-(void)backBtnClicked:(id)sender{
if (buttonIndex > 0)
{
buttonIndex -= 1;
}
if (buttonIndex < 1) {
_backButton.hidden = YES;
}
if (buttonIndex >=0) {
[_nextBtn setTitle:#"Next" forState:UIControlStateNormal];
PageContentViewController *startingViewController = [self viewControllerAtIndex:buttonIndex];
NSArray *viewControllers = #[startingViewController];
[self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil];
}}
-(void)nextBtnAction:(id)sender{
if (buttonIndex < 3)
{
buttonIndex += 1;
}
if(buttonIndex == _pageImages.count){
//Navigate Outside Pageview controller
} else{
if (buttonIndex ==3) {
[_nextBtn setTitle:#"Begin" forState:UIControlStateNormal];
}
_backButton.hidden = NO;
PageContentViewController *startingViewController = [self viewControllerAtIndex:buttonIndex];
NSArray *viewControllers = #[startingViewController];
[self.pageViewController setViewControllers:viewControllers direction:UIPageViewControllerNavigationDirectionForward animated:NO completion:nil];
}}
//BUTTON INDEX
-(NSInteger)presentationCountForPageViewController:(UIPageViewController *)pageViewController{
return [self.pageImages count];}
-(NSInteger)presentationIndexForPageViewController:(UIPageViewController *)pageViewController{
return buttonIndex;}