RXSwift - How to recall an api

Question

i created an observable for an api call and bind to a tableview. Now i am unclear how to call the same api once again? so as to do a refresh - say on an button click?. The following is my sample code.

Please let me know your thoughts it will be helpfull

 var items : Observable<[String]>? 
   func viewDidLoad(){

            items = fetchAllAnswers()
          items.bindTo(....).addDisposableTo(bag)
    }
   func fetchAllAnswers() -> Observable<[String]>{
   let api = Observable.create { (obsever: AnyObserver<[String]>) -> Disposable in
        let answers = API.allAnswers()
                     obsever.onNext(answers)
                     obsever.onCompleted()
                    return AnonymousDisposable{
                        print("api dispose called")
                    }
                }
                return api

            }

    func onClickRefresh()
   {
   // how to call api here again?


   //  let items = fetchAllAnswers() 
    // items.bindTo(....).addDisposableTo(bag)

   }

Svyatoslav · Accepted Answer · 2016-04-25T11:25:15.937

2

it's simple. You may to use Variable for update your items:

let items =  Variable([String]())

Next you must to bind items with your UITableView:

items.asObservable.bindTo(....).addDisposableTo(bag)

Next you may to update your items in subscriber:

fetchAllAnswers()
.subscribeNext { stringArray in 
    items.value = stringArray
}
.addDisposableTo(bag)

If you want to update your table by button click, you may to do next:

yourButton.rx_tap
.flatMap { void -> Observable<[String]> in
    return fetchAllAnswers()
}
.subscribeNext { stringArray in 
    items.value = stringArray
}
.addDisposableTo(bag)

edited Apr 25 '16 at 11:25

answered Apr 25 '16 at 11:04

Svyatoslav

1,350
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19

I have already bind it to a tableview to populate using .bindTo(). Does it means that i have to bind it again? please refer the code. i just want to call the api again hoping the data will repopulate in tableview – Aromal Sasidharan Apr 25 '16 at 11:11
I updated my answer. In your case i prefer to use Variable, can you try to use it? – Svyatoslav Apr 25 '16 at 12:06
Will try and let you know – Aromal Sasidharan Apr 25 '16 at 13:01
Any progress? If my answer helped you, mark it as right please. – Svyatoslav Apr 28 '16 at 07:00
Thanks! Have a great day – Aromal Sasidharan Apr 28 '16 at 10:20

score 1 · Answer 2 · answered Apr 26 '16 at 08:57

func viewDidLoad() {
  button.rx_tap.startWith().flatMap { _ in
    fetchAllAnswers()
  }.bindTo(...).addDisposableTo(bag)
}

flatMap will transform taps to the result of the observable the closure returns, here a String array.

startWith() will force rx_tap to emit a first value at subscription time, so that the first refresh behavior is kept.

RXSwift - How to recall an api

2 Answers2