Transferring an object from a Realm database to another UITabBar controller - ios

Question

Tell me, please, I'm trying to solve the problem of transferring an instance of a class to another controller using the Realm database.
I have a main controller that stores objects according to the model the following data:
class Route: Object {
#objc dynamic var routeImage: Data?
#objc dynamic var routeName: String?
#objc dynamic var numberOfPersons = 0.0
#objc dynamic var dateOfDeparture: String?
#objc dynamic var dateOfArrival: String?
let placeToVisit = List<Place>()
let person = List<Person>()
}
In the controller to which I need to transfer this data, I created
var currentRoute: Route!
In the Storyboard, I specified the identifier "showDetail" from the controller cell to the UITabBar, and in the main controller, I created a method:
override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
if segue.identifier == "showDetail" {
guard let indexPath = tableView.indexPathForSelectedRow else {return}
let newPlaceVC = segue.destination as! InformationViewController
newPlaceVC.currentRoute = routes[indexPath.row]
}
}
Error I got:
The methods in the UIConstraintBasedLayoutDebugging category on UIView listed in <UIKitCore/UIView.h> may also be helpful.
Could not cast value of type 'UITabBarController' (0x111ed8b10) to 'Organizer_Tourist.InformationViewController' (0x108dd0a70).
2019-10-07 14:30:35.626853+0800 Organizer Tourist[5467:2618892] Could not cast value of type 'UITabBarController' (0x111ed8b10) to 'Organizer_Tourist.InformationViewController' (0x108dd0a70).
(lldb)
But it is not valid, the application crashes by tap on the cell. I suppose this would work if there was not a tabBar, but a regular table, view controllers. I was looking for solutions and all I came across was implementation through singleton. Now I have a lot of questions, but will this really be the right decision? People say this violates the "modularity" of the application and carries its own problems. The question is how is this done through singleton? What to consider, where to start? Which method is worth editing?

Answer 1

Error said what is happening:
Could not cast value of type 'UITabBarController'
You are trying to cast segue.destination to typo InformationViewController which is not.
If you embed your InformationViewController in UITabBarController so you need to cast to your UITabBarController rather than InformationViewController.
Try something like this:
if segue.identifier == "showDetail" {
guard let indexPath = tableView.indexPathForSelectedRow else { return }
let tabBarController = segue.destination as! UITabBarController
UserSelectedRoute.shared.selectedRoute = routes[indexPath.row]
}
If you want to pass current selected route to InformationViewController you can create singleton object which will be hold current route
final class UserSelectedRoute {
private init() { }
static var shared = UserSelectedRoute()
var selectedRoute: Route?
}
And then in your InformationViewController you can have something like:
var currentRoute = UserSelectedRoute.shared.selectedRoute
Hope this will help you!