I implemented a lesson coordinator Why You Should Use The SwiftUI Coordinator Pattern

I googled the question about loading a view several times. I still haven’t found how to fix it. I realized that the problem is NavigationStack -> navigationDestination.

The main problem is that the view assembly runs several times. this is both the work of a worker and a request for data from the network...

struct SearchCoordinatorView: View {

    @StateObject private var coordinator = SearchCoordinator()
    @EnvironmentObject var globalFavoritesModel: GlobalFavoritesModel

    var body: some View {
        NavigationStack(path: self.$coordinator.path) {
            self.coordinator.changeFlow(flow: coordinator.flow, globalFavoritesModel: globalFavoritesModel)
                .navigationDestination(for: Flow.self) { page in
                    self.coordinator.changeFlow(flow: page, globalFavoritesModel: globalFavoritesModel)
                        .navigationBarTitle("", displayMode: .inline)
                        .navigationBarBackButtonHidden(true)
                }
        }
    }
}

protocol IShowJobPageSceneDelegate: AnyObject {
    func showJobPageScene(id: String)
}

protocol IShowPasswordSceneDelegate: AnyObject {
    func showPasswordScene(eMail: String)
}

protocol IShowSearchSceneDelegate: AnyObject {
    func showSearchScene()
}

protocol IBackSceneDelegate: AnyObject {
    func backScene()
}

enum Flow: Hashable {
    case loginScene
    case passwordScene(String)
    case vacancyScene
    case jobScene(String)
}

final class SearchCoordinator: ObservableObject {

    @Published var flow: Flow = .loginScene
    @Published var path: NavigationPath = NavigationPath()

    func push(_ page: Flow) {
        path.append(page)
    }

    func pop() {
        path.removeLast()
    }

    func popToRoot() {
        path.removeLast(path.count)
    }

    @ViewBuilder
    func changeFlow(flow: Flow, globalFavoritesModel: GlobalFavoritesModel) -> some View {
        switch (flow, globalFavoritesModel.isAuthorized) {
        case (.loginScene, false):
            let assembler = AssemblerLoginView()
            assembler.configurator(delegate: self)
        case (.passwordScene(let email), _):
            let assembler = AssemblerPasswordView()
            assembler.configurator(delegate: self, modelDTO: email)
        case (.vacancyScene, _):
            let assembler = AssemblerMainSearch()
            assembler.configurator(delegate: self, globalModel: globalFavoritesModel)
        case (.jobScene(let vacancyID), _):
            let assembler = AssemblerJobPage()
            assembler.configurator(backSceneDelegate: self, modelDTO: vacancyID)
        case (_, true):
            let assembler = AssemblerMainSearch()
            assembler.configurator(delegate: self, globalModel: globalFavoritesModel)
        }
    }
}

extension SearchCoordinator: IShowJobPageSceneDelegate {
    func showJobPageScene(id: String) {
        self.push(.jobScene(id))
    }
}

extension SearchCoordinator: IBackSceneDelegate {
    func backScene() {
        self.pop()
    }
}

extension SearchCoordinator: IShowPasswordSceneDelegate {
    func showPasswordScene(eMail: String) {
        self.push(.passwordScene(eMail))
    }
}

extension SearchCoordinator: IShowSearchSceneDelegate {
    func showSearchScene() {
        push(.vacancyScene)
    }
}

import SwiftUI

final class AssemblerMainSearch {
    func configurator(
        delegate: IShowJobPageSceneDelegate, globalModel: GlobalFavoritesModel
    ) -> some View {
        let fileManagers = FileLoadManager()
        // Сервисы.
        let declinationNumberService = DeclinationNumberService()
        let dateConvertService = DateConvertService()
        let convertorCounterVacancies = ConvertCounterVacanciesService()
        let assemblerURL = AssemblerURLService()
        // Менеджер работы с сетью.
        let networkManager = NetworkManager()
        // Менеджер работы с JSON.
        let jsonManager = DecodeJsonManager()
        // Конвекторы.
        let convertorVacancyDTO = ConvertorVacanciesDTO(
            declinationNumberService: declinationNumberService,
            dateConvertService: dateConvertService)
        let convertorOfferDTO = ConvertorOffersDTO()
        // Сборщик URL.

        let worker = MainSearchWorker(
            assemblerURL: assemblerURL,
            decodeJSONManager: jsonManager,
            networkManager: networkManager,
            convertorVacancyDTO: convertorVacancyDTO,
            convertorOffersDTO: convertorOfferDTO,
            convertorCounterVacancies: convertorCounterVacancies,
            fileManager: fileManagers
            )

        // Сборщик VIP.
        let viewModel = MainSearchViewModel(showJobPageSceneDelegate: delegate, globalModel: globalModel)
        let iterator = MainSearchIterator(viewModel: viewModel, worker: worker)
        iterator.fitchVacancies()
        var viewController = MainSearchView(mainSearchViewModel: viewModel)
        viewController.iterator = iterator

        return viewController

    }
}