How to connect Universal Links to UIViewController? - ios

Question

*Disclaimer: I've only been coding in iOS/XCode/Swift for a couple of weeks
I have Universal Links working in that clicking a link outside my app opens up the app and I catching the Url in the AppDelegate class.
So that's all good.
My question is... how do I then redirect to the correct UIViewController AND pass the controller some info from my URL? All Universal Link tutorials stop before they get to that part.
In particular I'm confused about the lifecycles of AppDelegate and how it relates to UIViewController.
My app had two UIViewController sitting under (is this right?) a UINavigationController.
What I've tried
I have tried handling the url event in AppDelegate, and setting a public property, and then in my ViewController getting access to the AppDelegate. HOWEVER, after the Universal Link is clicked, both viewDidLoad and viewWillAppear don't get called again :-/
What's the best way to redirect to a ViewController from AppDelegate? My goal is simply to load the root view controller BUT I need to pass in some data from the URL. How?

Answer 1

First, Read your URL.
Get your parameters from URL
Initiate your target controller
Set your parameter to that controller
Present controller on root view controller
let urlString = url.absoluteString
let queryArray = urlString.componentsSeparatedByString("/")
if queryArray[2].lowercaseString == "yourQuery" {
let queryId = Int(queryArray[3])
if self.window?.rootViewController?.presentedViewController != nil {
self.window?.rootViewController?.dismissViewControllerAnimated(false, completion: nil)
}
let queryVC = self.window?.rootViewController?.storyboard?.instantiateViewControllerWithIdentifier(QUERY_SCENE) as? QueryViewController
queryVC?.urlQueryId = queryId!
self.window?.rootViewController?.presentViewController(queryVC!, animated: true, completion: nil)
}
Edit:
Push a controller say 'PresentedViewController' on navigation controller and if rootViewController is also navigation controller
And on back press on controller 'OnBackPressViewController' present controller 'PresentedViewController'
if self.window?.rootViewController?.presentedViewController != nil {
self.window?.rootViewController?.dismissViewControllerAnimated(false, completion: nil)
}
let navController = self.window?.rootViewController?.storyboard?.instantiateInitialViewController() as? UINavigationController
let presentedVC = self.window?.rootViewController?.storyboard?.instantiateViewControllerWithIdentifier(PRESENTED_SCENE) as? PresentedViewController
//Pass parameters to PresentedViewController
let onBackPressViewController = self.window?.rootViewController?.storyboard?.instantiateViewControllerWithIdentifier(ON_BACK_PRESS_SCENE) as? OnBackPressViewController
navController!.pushViewController(onBackPressViewController!, animated: true)
navController!.pushViewController(presentedVC!, animated: true)
self.window?.rootViewController?.presentViewController(navController!, animated: true, completion: nil)
You can update your code according to that. Always remember that you have to present any view controller on rootViewController.

Answer 2

It depends on your app architecture. You can definitely assume that the AppDelegate has the reference to the rootViewController (window?.rootViewController). You should know what's the type of that controller. Then you can access to the other and so on. This question is, anyway, too much generic in my opinion.