Warning

This project is no longer maintained.
If you want to continue using ViewState, feel free to fork the repository and maintain your own version.

Overview

A View State library to return the results for each state

Support

iOS 15.0+ / macOS 12.0+ / tvOS 15.0+ / watchOS 7.0+ / visionOS 1+

Usage

In ViewModel calls the states that will return to ViewController

import ViewState

final class ViewModel {
    
    private var viewState = ViewState<Model, APIError>()
    private let service = Service()
    
    func fetchData() -> ViewState<Model, APIError> {
        viewState.fetchSource {
            self.service.getData { [weak self] result in
                switch result {
                case .success(let response):
                    self?.viewState.success(data: response)
                case .failure(let error):
                    self?.viewState.error(error: error)
               }
           }
        }

        return viewState
    }
}

In the ViewController it calls the ViewModel method and places the states of each one.

import UIKit
import ViewState

final class ViewController: UIViewController {

    private let viewModel = ViewModel()

    override func viewDidLoad() {
        super.viewDidLoad()

        loadData()
    }
    
    private func loadData() {
        viewModel.fetchData()
            .loadingObserver(onLoading)
            .successObserver(onSuccess)
            .errorObserver(onFailure)
    }
    
    private func onLoading() {
        // Event loading
    }
    
    private func onSuccess(response: Model) {
        // Event success
    }
    
    private func onFailure(error: APIError) {
        // Event error
    }
}

loadingObserver is optional, you can just use success and error

private func loadData() {
     viewModel.fetchData()
         .successObserver(onSuccess)
         .errorObserver(onFailure)
}

See a demo below. You can see this demo in our example 😃.

Installation

Swift Package Manager (SPM)

import PackageDescription
let package = Package(
    name: "<Your Product Name>",
    dependencies: [
       .package(
           url: "https://github.com/heroesofcode/ViewState", 
           exact: "2.1.0"
        )
    ],
    targets: [
        .target(
            name: "<Your Target Name>",
            dependencies: ["ViewState"]
        ),
    ]
)

License

ViewState is released under the MIT license. See LICENSE for details.