have a UINavigationBar title for each page in PageViewController - swift

Question

I have set up my pageViewController (embedded in a NavigationController) with an array of ViewControllers to use as the pages (seen below):
`
class PageViewController: UIPageViewController {
var arrayIndex: Int = 0
var navigationBar = UINavigationBar()
var pageControl = UIPageControl.self
override func viewDidLoad() {
super.viewDidLoad()
dataSource = self
if let firstViewController = orderedViewControllers.first {
setViewControllers([firstViewController],
direction: .Forward,
animated: true,
completion: nil)
}
}
// set up & order all view controllers
private(set) lazy var orderedViewControllers: [UIViewController] = {
return [self.newDayViewController("monday"),
self.newDayViewController("tuesday"),
self.newDayViewController("wednesday"),
self.newDayViewController("thursday")//,
self.newDayViewController("friday"),
self.newDayViewController("saturday"),
self.newDayViewController("sunday")
]
}()
// instantiate view controllers above that contain 'day' (easiest method to differentiate from other controllers)
private func newDayViewController(day: String) -> UIViewController {
return UIStoryboard(name: "Main", bundle: nil) .
instantiateViewControllerWithIdentifier("\(day)")
}
func pageViewController(pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
if (!completed) {
return
}
arrayIndex = Int(pageViewController.viewControllers!.first!.view.restorationIdentifier!)!
switch arrayIndex {
case 0:
navigationBar.topItem!.title = "Monday"
break
case 1:
navigationBar.topItem!.title = "Tuesday"
break
case 2:
navigationBar.topItem!.title = "Wednesday"
break
case 3:
navigationBar.topItem!.title = "Thursday"
default:
navigationBar.topItem!.title = "Timetable"
}
}
}
extension PageViewController: UIPageViewControllerDataSource {
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
guard let viewControllerIndex = orderedViewControllers.indexOf(viewController) else {
return nil
}
let previousIndex = viewControllerIndex - 1
guard previousIndex >= 0 else {
return orderedViewControllers.last
}
guard orderedViewControllers.count > previousIndex else {
return nil
}
return orderedViewControllers[previousIndex]
}
func pageViewController(pageViewController: UIPageViewController,
viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
guard let viewControllerIndex = orderedViewControllers.indexOf(viewController) else {
return nil
}
let nextIndex = viewControllerIndex + 1
let orderedViewControllersCount = orderedViewControllers.count
//MARK: - determine which viewController the user is on
guard orderedViewControllersCount != nextIndex else {
return orderedViewControllers.first
}
guard orderedViewControllersCount > nextIndex else {
return nil
}
return orderedViewControllers[nextIndex]
}
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return orderedViewControllers.count
}
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
guard let firstViewController = viewControllers?.first,
firstViewControllerIndex = orderedViewControllers.indexOf(firstViewController) else {
return 0
}
return firstViewControllerIndex
}
}
`
I am wondering how I could have it so that when the user is swiping through the pageViews, the UINavigationBar's title changes to the title of the view they are looking at ? e.g : When the user is looking at the mondayViewController, the title is monday and they can swipe to tuesday and the title will change etc.
Any suggestions are welcome
Thanks!

Answer 1

There are some errors in your code, first of all there isnt a UIPageViewControllerDelegate, so the delegates method will never be called.
Then, I dont know if your PageViewController really have a UINavigationController. To ensure that you can embed it by selecting your PageViewController and make the same thing as maded in picture:
so you can see in your storyboard both UINavigationController and UIPageViewController like this:
After you have all your day UIViewController created with each storyboard id, for example for monday:
you can modify you code like the code below:
import UIKit
class PageViewController: UIPageViewController,UIPageViewControllerDelegate {
var arrayIndex: Int = 0
var pageControl = UIPageControl.self
private(set) lazy var orderedViewControllers: [UIViewController] = {
return [self.newDayViewController("monday"),
self.newDayViewController("tuesday"),
self.newDayViewController("wednesday"),
self.newDayViewController("thursday"),
self.newDayViewController("friday"),
self.newDayViewController("saturday"),
self.newDayViewController("sunday")
]
}()
override func viewDidLoad() {
super.viewDidLoad()
dataSource = self
delegate = self
if let firstViewController = orderedViewControllers.first {
self.navigationController!.navigationBar.topItem!.title = "monday"
setViewControllers([firstViewController],
direction: .Forward,
animated: true,
completion: nil)
}
}
private func newDayViewController(day: String) -> UIViewController {
return UIStoryboard(name: "Main", bundle: nil) .
instantiateViewControllerWithIdentifier("\(day)")
}
func pageViewController(pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
if (!completed) {
return
}
if let firstViewController = viewControllers?.first,
let arrayIndex = orderedViewControllers.indexOf(firstViewController) {
switch arrayIndex {
case 0:
self.navigationController!.navigationBar.topItem!.title = "Monday"
break
case 1:
self.navigationController!.navigationBar.topItem!.title = "Tuesday"
break
case 2:
self.navigationController!.navigationBar.topItem!.title = "Wednesday"
break
case 3:
self.navigationController!.navigationBar.topItem!.title = "Thursday"
default:
self.navigationController!.navigationBar.topItem!.title = "Timetable"
}
}
}
}
extension PageViewController: UIPageViewControllerDataSource {
func pageViewController(pageViewController: UIPageViewController, viewControllerBeforeViewController viewController: UIViewController) -> UIViewController? {
guard let viewControllerIndex = orderedViewControllers.indexOf(viewController) else {
return nil
}
let previousIndex = viewControllerIndex - 1
guard previousIndex >= 0 else {
return orderedViewControllers.last
}
guard orderedViewControllers.count > previousIndex else {
return nil
}
return orderedViewControllers[previousIndex]
}
func pageViewController(pageViewController: UIPageViewController,
viewControllerAfterViewController viewController: UIViewController) -> UIViewController? {
guard let viewControllerIndex = orderedViewControllers.indexOf(viewController) else {
return nil
}
let nextIndex = viewControllerIndex + 1
let orderedViewControllersCount = orderedViewControllers.count
//MARK: - determine which viewController the user is o
guard orderedViewControllersCount != nextIndex else {
return orderedViewControllers.first
}
guard orderedViewControllersCount > nextIndex else {
return nil
}
return orderedViewControllers[nextIndex]
}
func presentationCountForPageViewController(pageViewController: UIPageViewController) -> Int {
return orderedViewControllers.count
}
func presentationIndexForPageViewController(pageViewController: UIPageViewController) -> Int {
guard let firstViewController = viewControllers?.first,
firstViewControllerIndex = orderedViewControllers.indexOf(firstViewController) else {
return 0
}
return firstViewControllerIndex
}
}