Why does pushViewController doesn't work after navigating through Dynamic Link? - ios

I'm building an app that can receive Firebase's Dynamic Link and redirects it into a certain UIViewController after clicking the link. So based on this question that I asked, I have the code in AppDelegate.swift that navigates the app to the UIViewController like this:
func goToDynamicLinkVC() { // This function is in AppDelegate.swift
let destinationStoryboard: UIStoryboard = UIStoryboard(name: "DynamicLink", bundle: nil)
let destinationVC = destinationStoryboard.instantiateViewController(withIdentifier: "DynamicLinkView") as? DynamicLinkVC
self.window = UIWindow(frame: UIScreen.main.bounds)
self.window?.rootViewController = destinationVC
self.window?.makeKeyAndVisible()
}
And in that UIViewController I also have a function that moves to another UIViewController if a user pressed a button like this:
func routeToDynamicForm() { // This function is in DynamicLinkVC class
let destinationVC = UIStoryboard(name: "DynamicLink", bundle: nil).instantiateViewController(withIdentifier: "DynamicFormView") as! DynamicFormVC
self.navigationController?.pushViewController(destinationVC, animated: true)
}
But weirdly enough now that I pressed the button it doesn't move me to the next View Controller (in this case, DynamicFormVC). I've tried to debug the button whether it's working or not by doing this:
print("button tapped")
It shows the message on the debug area, but it still doesn't redirects to the next view controller. So what can I do to resolve this? If you need more information feel free to ask and I will provide it to you. Thank you.

I changed the goToDynamicLinkVC function to something like this:
func goToDynamicLinkVC() { // This function is in AppDelegate.swift
let destinationStoryboard: UIStoryboard = UIStoryboard(name: "DynamicLink", bundle: nil)
let destinationVC = destinationStoryboard.instantiateViewController(withIdentifier: "DynamicLinkView")
let navController = UINavigationController()
navController.setViewControllers([destinationVC], animated: true)
self.window?.rootViewController = navController
}

Related

Bar item not show when I use segue programmatically

I’m building an app which has a main vc that only existing user can log in to. The main page is the initial vc so I embed in the navigation bar to it. When I open the app in the first time I can see the bar items, but when I sign out, and log in again I can’t see the bar items, someone know why? Should I add some code? or maybe change some definitions?
I’m using segue programmatically like this:
private var handle: AuthStateDidChangeListenerHandle?
handle = Auth.auth().addStateDidChangeListener({ (auth, user) in
if user == nil{
if let vc = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "Home") as? MainVC
{
self.present(vc, animated: true, completion: nil)
}
}else{
//keep going with the code...
})
In the simulator it starts with the main vc then I sign out (pic 1), then I log in (pic 2) and get back to the main vc but now I can’t see the bar items (pic 3).
link to the app pictures
you must present your main vc in navigationcontroller
private var handle: AuthStateDidChangeListenerHandle?
handle = Auth.auth().addStateDidChangeListener({ (auth, user) in
if user == nil{
if let vc = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "Home") as? MainVC
{
let navVc = UINavigationController(rootViewController: vc)
self.present(navVc, animated: true, completion: nil)
}
}else{
//keep going with the code...
})

Swift problem with sending data to another ViewController

Variable cards in second ViewController should be updated in first VC on buttonClick.
I tested the sending data from the first VC with printing data and it works good.
Here is the code:
#IBAction func btnTapped(_ sender: Any) {
let mainStoryboard = UIStoryboard(name: "Main", bundle: Bundle.main)
let secondVC = (mainStoryboard.instantiateViewController(withIdentifier: "SecondViewController") as! SecondViewController)
for card in setsOfCardsByLevel {
cardVC.cards.append(card)
}
print("Number of cards to send - \(cardVC.secondVC.count)") //PRINTS RIGHT NUMBER
presentVC("SecondViewController") //WORKS FINE
}
Maybe you dont need this method below but I will put it just in case:
func presentVC(_ VC_Name: String) {
guard let myVC = self.storyboard?.instantiateViewController(withIdentifier: VC_Name) else { return }
let navController = UINavigationController(rootViewController: myVC)
navController.modalPresentationStyle = .fullScreen
self.navigationController?.present(navController, animated: true, completion: nil)
}
PROBLEM: When I print cards in the secondViewController, they are empty(count = 0). How?
EDIT: While waiting for answer on StackOverflow I changed presentViewController to pushViewController and print in secondVC shows right number. I am confused.
Your problem is in your presentVC method. First in your btnTapped method you instantiate your second viewController and assing your cards, again in your presentVC method instantiate another controller and it's not relevant to the first you define in your btnTapped and cards variable not assigned. For solution you can pass your secondVC as a parameter to your presentVC, not the name of storyboard

How to reopen application after login

I'm an android developer. in android, when user login in application, I will re-open the MainActivity class ( controller ) to refresh some views.
in iOS applications, how to do this scenario ?
You can reopen you default/LandingViewController.
Suppose you have a View Controller with name LandingViewController
When you successfully logged in all you need is to re instantiate the LandingViewController
In AppDelegate class make a function with name
func userDidLoggedIn(){
let storyboard = UIStoryboard(name: "Main", bundle: nil)//Replace Main With your own storyboard name containing LandingViewController
let landingViewController = storyboard.instantiateViewController(withIdentifier: "LandingViewControllerIdentifier")//Pass your LandingViewController Identier that you have set in your storyboard file.
guard let subviews = self.window?.subviews else {
return
}
for view in subviews {
view.removeFromSuperview()
}
self.window?.rootViewController = landingViewController
}
Now Simply Call this Function where ever in the entire project like this In your case write below lines in the completion block of login request API.
let delegate = UIApplication.shared.delegate as! AppDelegate
delegate. userDidLoggedIn()
Once user login, you can change your rootviewcontroller like this:
var nav_VC: UIViewController?
func onSuccessfulLogin()
{
let storyboard = UIStoryboard.init(name: "Main", bundle: nil)
nav_VC = nil
if nav_VC == nil {
nav_VC = storyboard.instantiateViewController(withIdentifier: "home_nav")
}
self.window?.rootViewController = nav_VC
self.window?.makeKeyAndVisible()
}

revealViewController() always returns nil

I'm having some troubles with revealViewController in Xcode 7.2 and iOS 9.2.
My app starts with a view controller embedded in a navigation controller to perform a login.
After login, or if the login token is present, I jump to another view controller embedded in a navigation controller with the following code:
let homePage = self.storyboard?.instantiateViewControllerWithIdentifier("HomeViewController") as! HomeViewController
let homePageNav = UINavigationController(rootViewController: homePage)
let appDelegate = UIApplication.sharedApplication().delegate as! AppDelegate
appDelegate.window?.rootViewController = homePageNav
In this home view controller I would like to have a left navigation menu with SWRealViewController.
I had the SWRealViewController view linked with sw_front to my home navigation controller, and the following code:
if (self.revealViewController() != nil) {
self.menuButton.target = self.revealViewController()
self.menuButton.action = "revealToggle:"
self.view.addGestureRecognizer(self.revealViewController().panGestureRecognizer())
But self.revealViewController() always returns nil, so it does not work.
I think I lost the revealViewController somewhere (maybe when I jump from the first navigation controller to the second) but I do not know what to do.
The most convenient to be a reason for the revealViewController to be nil
is you didn't connect segues correctly in stroyboard.
See this tutorial it's quite easy to follow.
Update
If in your case you just need to open a login vc if the user is not logged in you may do like this:
in AppDelegate
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
var rootVCStoryboardId = userIsLoggedin ? "SWRevealViewController" : "LoginViewController"
self.window?.rootViewController = UIStoryboard(name: Storyboards.main, bundle: NSBundle.mainBundle()).instantiateViewControllerWithIdentifier(rootVCStoryboardId)
Where SWRevealViewController is the stroyboard id for SWRevealViewController and LoginViewController is the storyboard id for your login view controller(or its navigation controller if exists).
In case someone is wondering how to do a manual segue, this is what worked for me at the end.
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let sw = storyboard.instantiateViewControllerWithIdentifier("SWRevealViewController") as! SWRevealViewController
self.view.window?.rootViewController = sw
let destinationController = self.storyboard?.instantiateViewControllerWithIdentifier("StoryboardID") as! NameOfViewController
let navigationController = UINavigationController(rootViewController: destinationController)
sw.pushFrontViewController(navigationController, animated: true)
Incase you are skipping login scene based on the current user information, then make sure to instantiate the storyboard with SWRevealViewController. See below code for reference:
if User.currentUser != nil {
//There is a current user
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let vc = storyboard.instantiateViewControllerWithIdentifier("SWRevealViewController")
window?.rootViewController = vc
}
else{
//No current user
}

Checking if ViewController is already in background or not

I have an app which starts with different VCs depending whether the user is already logged in or not.
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
window = UIWindow.init(frame: UIScreen.mainScreen().bounds)
let storyboard = UIStoryboard.init(name: "Main", bundle: nil)
let initialViewController: UIViewController
if DataManager.getInstance().getUserInfo() == nil {
initialViewController = storyboard.instantiateViewControllerWithIdentifier("authenticationViewController")
} else {
initialViewController = storyboard.instantiateViewControllerWithIdentifier("locationsNavigationViewController")
}
window!.rootViewController = initialViewController;
window!.makeKeyAndVisible();
return true
}
If the user is not logged in, the app starts with AuthenticationViewController, otherwise it starts with LocationsNavigationViewController, which is a NavigationViewController
In the latter VC, the is a button for logout. The problem is when the user taps on that button, I don't know if I have to dismiss the LocationsNavigationViewController (because AuthenticationViewController is in background) or if I have to dismiss LocationsNavigationViewController and perform a segue for opening the AuthenticationViewController.
So far, I have just covered the first use case. So in LocationsNavigationViewController I call this function
func showAuthentication() {
dismissViewControllerAnimated(true, completion: nil)
}
But when the app starts with LocationsNavigationViewController dismiss the VC is not enough of course, because the the AuthenticationViewController has never been instantiated.
How can I solve this please?
self.navigationController?.viewControllers
This is an array which will contain all your previous view controller. You can enumerate it and check whether your view controller is exist or not.
If you are using UINavigationController then you can check any UIViewController present or not!
let rootViewController = application.windows[0].rootViewController as! UINavigationController
let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main", bundle: nil)
if !rootViewController.viewControllers.contains(UIViewController_Class()){
let notificationVC = mainStoryboard.instantiateViewControllerWithIdentifier(constInstance.notificationsIdentifier) as! UIViewController_Class_Name
rootViewController.pushViewController(notificationVC, animated: false)
}
Hope this helps!
Thanks to Sohil's answer, I change the showAuthentication function in this way
func showAuthentication() {
//Since the app can start with different VC, I have to check which is the window root VC
if UIApplication.sharedApplication().windows[0].rootViewController is AuthenticationViewController {
dismissViewControllerAnimated(true, completion: nil)
} else {
performSegueWithIdentifier("authenticationSegue", sender: self)
}
}
And added a segue from the NavigationViewController to the AuthenticationViewController, called authenticationSegue
Pretty simple solution.
You can create one function in appdelegate for logout
and in logout function chanege rootviewcontroller of window like
func logoutUser()
{
var login: UIViewController?
login = LoginViewController(nibName : "LoginViewController", bundle : nil)
let nav = UINavigationController(rootViewController: login!)
self.window?.rootViewController = nav
}

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