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Combine / UIViewController- Is it a good practice?

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I am using the Combine framework, and I have a question about my implementation. Is it a good practice to embed a view controller presentation in a Future and wait for this view controller to call back before publishing a value?

The following function will display a view controller (requester), wait for the user to fill the value, and send this value in the promise.

 private func requestDisplayName() -> Future<String, Never> {
        Future { [weak self] promise in
            guard let self = self else { return }
            let requester = RequestDisplayNameViewController()
                .receive(on: DispatchQueue.main)
                .sink { displayName in
                .store(in: &self.cancellables)
            self.mainVC.present(requester, animated: true, completion: nil)

displayName is a CurrentValueSubject<String, Never> that sends a value once the user hit a validate button in the RequestDisplayNameViewController

On the other side, I have an apiObserver waiting to receive the display name from the server, and once the data obtained, it will check if the value is nil or not, and according to this value, the requestDisplayName() will be called.

apiObserver.receive(on: DispatchQueue.main)
            .flatMap({ displayNameFromServer -> AnyPublisher<String, Never> in
                if let displayNameFromServer = displayNameFromServer {
                    return Result.Publisher(displayNameFromServer).eraseToAnyPublisher()
                return self.requestDisplayName().eraseToAnyPublisher()
            .flatMap({ displayName in
                // Make an action with the displayName
            // ..

Thank you.


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