我是RxSwift的新手,并尝试使用MVVM架构实现应用程序 . 我有查看模型:
class CategoriesViewModel {
fileprivate let api: APIService
fileprivate let database: DatabaseService
let categories: Results<Category>
// Input
let actionRequest = PublishSubject<Void>()
// Output
let changeset: Observable<(AnyRealmCollection<Category>, RealmChangeset?)>
let apiSuccess: Observable<Void>
let apiFailure: Observable<Error>
init(api: APIService, database: DatabaseService) {
self.api = api
self.database = database
categories = database.realm.objects(Category.self).sorted(byKeyPath: Category.KeyPath.name)
changeset = Observable.changeset(from: categories)
let requestResult = actionRequest
.flatMapLatest { [weak api] _ -> Observable<Event<[Category]>> in
guard let strongAPI = api else {
return Observable.empty()
}
let request = APIService.MappableRequest(Category.self, resource: .categories)
return strongAPI.mappedArrayObservable(from: request).materialize()
}
.shareReplayLatestWhileConnected()
apiSuccess = requestResult
.map { $0.element }
.filterNil()
.flatMapLatest { [weak database] newObjects -> Observable<Void> in
guard let strongDatabase = database else {
return Observable.empty()
}
return strongDatabase.updateObservable(with: newObjects)
}
apiFailure = requestResult
.map { $0.error }
.filterNil()
}
}
我在视图控制器中有以下binginds:
viewModel.apiSuccess
.map { _ in false }
.bind(to: refreshControl.rx.isRefreshing)
.disposed(by: disposeBag)
viewModel.apiFailure
.map { _ in false }
.bind(to: refreshControl.rx.isRefreshing)
.disposed(by: disposeBag)
但是,如果我评论绑定,部分数据库更新将停止执行 . 无论如何我都需要让它执行,而不需要在视图模型中使用dispose bag . 可能吗?
还有一点额外的问题:我应该在我的视图模型代码中使用弱强舞 api
/ database
和 return Observable.empty()
,还是我可以安全地使用 unowned api
/ unowned database
?
谢谢 .
UPD:
APIService中返回observable的函数:
func mappedArrayObservable<T>(from request: MappableRequest<T>) -> Observable<[T]> {
let jsonArray = SessionManager.jsonArrayObservable(with: request.urlRequest, isSecured: request.isSecured)
return jsonArray.mapResponse(on: mappingSheduler, { Mapper<T>().mapArray(JSONArray: $0) })
}
1 回答
除非有订户准备接收结果,否则工作无法完成 .
您的DatabaseService需要有一个dispose包并订阅
Observable<[Category]>
. 就像是:然后
apiSuccess = database.categoriesUpdated
和database.updateObservable(with: requestResult.map { $0.element }.filterNil())