How to pass data between UIPageViewControllers in swift? - ios

Question

I have a UIPageViewController with 4 View Controllers in it. In the second VC, the user enters some data. In the last VC, there is a button that the user clicks to insert these data into DB. I want to pass the data from the second VC to the fourth one. All my search results show segues, but the VCs are not directly connected.
So I thought of using delegates, but it is not working for me.
Code:
UIPageViewController:
import UIKit
class PageViewController: UIPageViewController {
var pageControl = UIPageControl()
fileprivate lazy var pages: [UIViewController] = {
return [
self.getViewController(withIdentifier: "locationStoryBoard"),
self.getViewController(withIdentifier: "notificationStoryboard"),
self.getViewController(withIdentifier: "weightStoryboard"),
self.getViewController(withIdentifier: "bloodTypeStoryboard"),
self.getViewController(withIdentifier: "ageStoryboard"),
self.getViewController(withIdentifier: "genderStoryboard"),
self.getViewController(withIdentifier: "mobileNumberStoryboard"),
self.getViewController(withIdentifier: "preventionStoryboard")
]
}()
fileprivate func getViewController(withIdentifier identifier: String) -> UIViewController
{
return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: identifier)
}
override func viewDidLoad()
{
super.viewDidLoad()
self.dataSource = self
self.delegate = self
if let firstVC = pages.first
{
setViewControllers([firstVC], direction: .forward, animated: true, completion: nil)
}
configurePageControl()
}
//Page Control (3 dots)
func configurePageControl() {
pageControl = UIPageControl(frame: CGRect(x: 0,y: UIScreen.main.bounds.maxY - 50,width: UIScreen.main.bounds.width,height: 50))
self.pageControl.numberOfPages = pages.count
self.pageControl.currentPage = 0
self.pageControl.alpha = 0.5
self.pageControl.tintColor = UIColor.black
self.pageControl.pageIndicatorTintColor = UIColor.white
self.pageControl.currentPageIndicatorTintColor = #colorLiteral(red: 0.986409843, green: 0.4042935669, blue: 0.4366002679, alpha: 1)
self.view.addSubview(pageControl)
}
}
//MARK: - UIPageViewControllerDataSource methods
extension PageViewController: UIPageViewControllerDataSource
{
func pageViewController(_ pageViewController: UIPageViewController,
viewControllerBefore viewController: UIViewController) -> UIViewController? {
let currentIndex = pages.firstIndex(of: viewController)!
let previousIndex = currentIndex - 1
return (previousIndex == -1) ? nil : pages[previousIndex]
}
func pageViewController(_ pageViewController: UIPageViewController,
viewControllerAfter viewController: UIViewController) -> UIViewController? {
let currentIndex = pages.firstIndex(of: viewController)!
let nextIndex = currentIndex + 1
return (nextIndex == pages.count) ? nil : pages[nextIndex]
}
}
//MARK: - UIPageViewControllerDelegate methods
extension PageViewController: UIPageViewControllerDelegate {
func pageViewController(_ pageViewController: UIPageViewController, didFinishAnimating finished: Bool, previousViewControllers: [UIViewController], transitionCompleted completed: Bool) {
let pageContentViewController = pageViewController.viewControllers![0]
self.pageControl.currentPage = pages.firstIndex(of: pageContentViewController)!
}
}
First VC
protocol NameAndMobileDelegates {
func passName(nameToBePassed: String)
}
class MobileNumberViewController: UIViewController, UITextFieldDelegate {
var delegate: NameAndMobileDelegates?
...
func textFieldDidEndEditing(_ textField: UITextField) {
switch textField.tag {
case 1:
name = textField.text!
self.delegate?.passName(nameToBePassed: name)
print(name)
case 2:
mobileNumber = textField.text!
print(mobileNumber)
default: break
}
}
In the 4th VC:
// MARK: - Name and Number Delegate Methods
extension DiseasesViewController: NameAndMobileDelegates {
func passName(nameToBePassed: String) {
print("protocol worked")
}
Thank you in advance

Answer 1

Do
if let fourVC = pages[3] as? FourthVC {
fourVC.delegate = pages.first as! FirstVC
}
then
class FourthVC:UIViewController {
weak var delegate:FirstVC?