如何使用MVVM和RxSwift快速显示/隐藏progressHUD

Question

我从MVVM开始,以便将逻辑代码从视图中分离出来.但我有点担心在点击发出请求的按钮时将progressHUD相关代码放在哪里.

之前,我曾经这样做过:

//Before 
@IBAction func startRequestTapped() {
   SVProgressHUD.show()
    self.apiClient.requestObservable().subscribe(onError: { (error) in
        SVProgressHUD.hide()                    
    }, onCompleted: { 
        SVProgressHUD.hide()                                        
    })
}

但是当我使用mvvm时,我确实喜欢这样:

//In the viewModel
public var validateButtonDidTap = PublishSubject<Void>()
init() {
    validateButtonDidTap.flatMap { (_)
        return self.apiClient.requestObservable()
    }
}


   // In the viewController
viewDidLoad() {
    let tap = self.validateButton.rx.tap
    tap.bindTo(self.viewModel.validateButtonDidTap)
}

其中,我不知道将ProgressHUD隐藏或显示放在哪里.

Answer 1

马克答案是对的,但我会一步一步地指导你.

让我们打算你试着登录.

1. 复制项目中的ActivityIndi​​cator.swift文件.

2. 在viewModel:

   //MARK: - Properties
   
   /// The http client
   private let apiClient: YourApiClient
   
   /// Clousure when button is tapped
   var didTappedButton: () -> Void = {}
   
   /// The user 
   var user: Observable<User>
   
   /// Is signing process in progress
   let signingIn: Observable<Bool> = ActivityIndicator().asObservable()
   
   //MARK: - Initialization
   
   init(client: YourApiClient) {
       self.client = client
   
       self.didTappedButton = { [weak self] in
           self.user = self.apiClient
                           .yourSignInRequest()
                           .trackActivity(self.signingIn)
                           .observeOn(MainScheduler.instance)
       }
   }
   

3. 创建SVProgressHUD的扩展:(我不知道SVProgressHUD库,但它会是这样的.请在需要时修复它)

   extension Reactive where Base: SVProgressHUD {
   
       /// Bindable sink for `show()`, `hide()` methods.
       public static var isAnimating: UIBindingObserver<Base, Bool> {
           return UIBindingObserver(UIElement: self.base) { progressHUD, isVisible in
               if isVisible {
                   progressHUD.show() // or other show methods
               } else {
                   progressHUD.dismiss() // or other hide methods
               }
           }
       }
   
   }
   

4. 在你的viewController:

   @IBAction func startRequestTapped() {
       viewModel.didTappedButton()
   }
   
   override func viewDidLoad() {
   
       // ...
   
       viewModel.signingIn
                .bindTo(SVProgressHUD.rx.isAnimating)
                .addDisposableTo(disposeBag)
   }
   

Answer 2

接受的答案更新为Swift 4,RxSwift 4.0.0和SVProgressHUD 2.2.2:

3-扩展:

extension Reactive where Base: SVProgressHUD {

   public static var isAnimating: Binder<Bool> {
      return Binder(UIApplication.shared) {progressHUD, isVisible in
         if isVisible {
            SVProgressHUD.show()
         } else {
            SVProgressHUD.dismiss()
         }
      }
   }

}

4-控制器:

viewModel.signingIn.asObservable().bind(to: SVProgressHUD.rx.isAnimating).disposed(by: disposeBag)