I've to get value from my JSON and pass this string to a variable in the second View. So, my problem it's not get value from JSON because I did it. How I can do it. I've just tried prepare (for segue) and other code but any of thats worked. Do you have an advice for me?
I hope I have been clearer. Sorry.
1) First
2) Second
This should do it.
let mainStoryboard = UIStoryboard.init(name: "Main", bundle: nil)
let homeViewController = mainStoryboard.instantiateViewController(withIdentifier: "Your Home View Controller identifier") as! SecondView
homeViewController.title = self.title
homeViewController.description = self.description
self.navigationController?.pushViewController(homeViewController, animated: true)
Related
I am new to swift but I have implemented FCM but I am having an issue. When I click the notification it loads the NotificationsViewController with the following code.
let sb = UIStoryboard(name: "Main", bundle: nil)
let otherVC = sb.instantiateViewController(withIdentifier: "NotificationsViewController") as! NotificationsViewController
self.window?.rootViewController = otherVC;
Once the NotificationsViewController is loaded I use the following code in on the back button to reassign the root view back to the normal ViewController.
let mainStoryBoard = UIStoryboard(name: "Main", bundle: nil)
let redViewController = mainStoryBoard.instantiateViewController(withIdentifier: "splashScreen") as! ViewController
let appDelegate = UIApplication.shared.delegate as! AppDelegate
appDelegate.window?.rootViewController = redViewController
Once I am on the splashScreen it should show a quick image and then move on to the main dashboard using this code.
let vw = UIStoryboard.init(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "DashboardViewController") as! DashboardViewController
self.navigationController?.pushViewController(vw, animated: true)
The problem I am having is the splashScreen code is not working when the app loads it from NotificationsViewController, it just hangs on that VC, but if I load the splashScreen without reassigning the root view it works.
So is there some other way I should be doing this? I just want to take the user to the NotificationsViewController when they click the notification and then back to the main part of the app when they click a back button.
If you just need to show the NotificationViewController, you just present it in fullscreen. You can set it by vc.modalPresentationStyle = .fullScreen. Then to go back to the main app, you just need to dismiss it. :)
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
I am trying to init my core data stack with the init VC of my app. To do this I want to pass the core data manager i have created into the first VC upon loading.
I thought this code would make sense to pass the coredatamanager into the VC, however I get errors whichever way i write this code, im sure im missing something simple?
// Initialize Storyboard
let storyboard = UIStoryboard(name: "RoutineController", bundle: Bundle.main)
// Instantiate Initial View Controller
if let viewController = storyboard.instantiateInitialViewController() as? ViewController {
// Configure View Controller
viewController.coreDataManager = coreDataManager
// Set Root View Controller
window?.rootViewController = viewController
}
Error is simply:
Use of undeclared type 'ViewController'
However if i delete 'as? ViewController' I get an error on the following line that viewController has no property coreDataManager.
Is there some sort of delegate i need to define in the viewdidload of the view controller in sending to?
EDIT Revised my code to correct the storyboard ID, however the code inside the {} doesnt seem to execute, i get the printed error i wrote due to the if let failing, so this still isnt the right way to set the viewController...any ideas as to why?
// Initialize Storyboard
let storyboard = UIStoryboard(name: "Main", bundle: Bundle.main)
// Instantiate Initial View Controller
if let viewController = storyboard.instantiateInitialViewController() as? RoutineController {
// Configure View Controller
print("SENDING THIS INFO TO THE FIRST VC \(self.coreDataManager)")
viewController.coreDataManager = self.coreDataManager
// Set Root View Controller
window?.rootViewController = viewController
} else {
print("WE COULDNT SET VIEWCONTROLLER AS THE DESIGNATED VC SO MOC WASNT PASSED")
}
This is your problem:
as? ViewController
should be
as! UIViewController
alternatively this should also work:
as! RoutineController
Select the RoutineController in your storyboard and set the storyboard ID
Then use the Storyboard ID here:
if let viewController = storyboard.instantiateViewController(withIdentifier: "<storyboardID>") as? RoutineController {
The solution was that you need to define an identifier in the if let viewController to find it successfully, the working code is as follows:
let storyboard = UIStoryboard(name: "Main", bundle: nil)
if let viewController = storyboard.instantiateViewController(withIdentifier: "TabBarController") as? TabBarController {
viewController.coreDataManager = self.coreDataManager
window?.rootViewController = viewController
The picture is just an example...
So basically I want to pass data from RED to BLUE but i have to go through GREEN.. is there a way to just pass the data straight to BLUE without it having to go through GREEN?
What I'm doing now is the conventional method of passing the data to GREEN then having GREEN read it and pass it on to BLUE
But my app has a lot of ViewControllers and I wish to be able to pass it straight to the final page (BLUE page) is there a way? Sorry I'm new to the Swift
If you try to pass data from _Red to _Blue, without _Green - it about bad architecture, becouse if something changed in logic of app, and you need to changed flow of controllers - you will feel a lot of headache...
You can wrap your data in object and pass through or you can make DataController which will be manage your data, and your ViewController's will be get\set it by Datacontroller interface
Use a simple swift class e.g Sharedclass to set a variable and then get the value of the variable from the same Sharedclass. Example is given below
import Foundation
class SharedClass {
static let sharedInstance = SharedClass()
var phoneNumber = ""
}
To set the variable
SharedClass.sharedInstance.phoneNumber = "123456"
To get the variable
BLUEViewController.phoneNumber = SharedClass.sharedInstance.phoneNumber
You can push your navigationController directly to one of your viewControllers. Try this;
let storyboard = UIStoryboard(name: "Main", bundle: nil)
if let blueController = storyboard.instantiateViewController(withIdentifier: "BlueViewController") as? BluewViewController {
blueController.passedData = passedData
navigationController?.pushViewController(blueController, animated: true)
}
Or you can just present it too. Instead of pushing in navigation controller.
let storyboard = UIStoryboard(name: "Main", bundle: nil)
if let blueController = storyboard.instantiateViewController(withIdentifier: "BlueViewController") as? BluewViewController {
blueController.passedData = passedData
present(blueController, animated: true, completion: nil)
}
I am currently writing an app in Swift and I implemented all my UI programatically. I would it kind of exhausting, so recently I decided to use storyboard but I am stuck with a bug.
When passing over the mainContext from the AppDelegate to the FirstViewController, the value of the mainContext is nil. In the first place, when I wrote everything programmatically, my code looked like this:
let vc = FirstViewController()
vc.mainContext = mainContext
window?.rootViewController = vc
But now that I am working with StoryBoard, this is not valid anymore because I have to instantiate the view with its ID, like this:
let storyboard = UIStoryboard(name: "Main", bundle: nil)
var vc = storyboard.instantiateViewControllerWithIdentifier("FirstView") as! FirstViewController
vc.mainContext = mainContext
But in this case, the context is nil. If I don't instantiate the VC like this, my outlets are nil and I get this error:
fatal error: unexpectedly found nil while unwrapping an Optional value
Does someone know a way to pass my mainContext?
You're not accessing the rootViewController, you're creating a new view controller and not doing anything with it, to access the rootViewController replace this
let storyboard = UIStoryboard(name: "Main", bundle: nil)
var vc = storyboard.instantiateViewControllerWithIdentifier("FirstView") as! FirstViewController
vc.mainContext = mainContext
with
if let vc = self.window?.rootViewController as? FirstViewController {
vc.mainContext = mainContext
}