Page View Controller viewDidLoad() Issues - swift

Question

I'm learning Swift/Xcode and trying to create an app with three pages that you can swipe back and forth using a Page View Controller. The issues I'm having lie in the UIViewController subclass, more specifically the viewDidLoad() function. I'm getting errors like "value of type 'NameOfMyClass' has no member datasource/delegate" and "use of unresolved identifier "setViewControllers". I've followed many tutorials and checked other posts but no one seems to be having these issues. When I attempted to run this I would get a black screen, and now I get a terminated due to signal 15 error.
Here's the relevant code where the errors are popping up:
import UIKit
class RootPageViewController: UIViewController,
UIPageViewControllerDataSource, UIPageViewControllerDelegate {
lazy var viewControllerList:[UIViewController] = {
return [self.VCInstance(name: "MissionOne"),
self.VCInstance(name: "MissionTwo"),
self.VCInstance(name: "MissionThree")]
}()
private func VCInstance(name: String) -> UIViewController {
return UIStoryboard(name: "Main", bundle:
nil).instantiateViewController(withIdentifier: name)
}
override func viewDidLoad() {
super.viewDidLoad()
self.dataSource = self //...has no member 'dataSource' error
self.delegate = self //...has no member 'delegate' error
if let MissionOne = viewControllerList.first {
setViewControllers([MissionOne], direction: .forward, animated:
true, completion: nil)
//use of unresolved indentifier 'setViewControllers' error
}
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
The other issue I'm having, and it may be related, is that the Page View Controller is not accepting/recognizing my class file to set as the custom class in the story board.
Thanks in advance for any insight or suggestions.

Answer 1

your RootPageViewController is subclass of UIViewController, not a UIPageViewController

Answer 2

I looks to me that you are mixing two different controllers here.
What you want to do is add 3 RootPageViewController to a UIPageViewController, yet here you are trying to add 3 RootPageViewControllers to a RootPageViewController!
One way to fix it is to have a RootPageViewController and a separate UIPageViewController which will contain all RootPageViewControllers like so:
// This is a UIPageViewController containing all RootPages
class PagesViewController: UIPageViewController, UIPageViewControllerDataSource, UIPageViewControllerDelegate {
lazy var viewControllerList:[UIViewController] = {
return [RootPageViewController.VCInstance(name: "MissionOne"),
RootPageViewController.VCInstance(name: "MissionTwo"),
RootPageViewController.VCInstance(name: "MissionThree")]
}()
override func viewDidLoad() {
super.viewDidLoad()
self.dataSource = self
self.delegate = self
if let MissionOne = viewControllerList.first {
setViewControllers([MissionOne], direction: .forward, animated:
true, completion: nil)
}
}
}
And the RootPageViewController which will be added in the UIPageViewController above:
// This is a UIViewController representing a single page
class RootPageViewController: UIViewController {
static func VCInstance(name: String) -> UIViewController {
return UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: name)
}
// Do what you need a page to do...
}
With such a construction you will have all your errors solved and you will also be able to use PagesViewController as custom class in your Storyboard!