RxSwift: binding PublishSubject to multiple buttons and receive sender

Question

I am working on an app that presents 26 (alphabet) buttons. Right now they're all connected to the same function in the ViewController, that in turn calls another function in the ViewModel, and finally this function calls publishSubject.onNext(). The ViewController subscribes to the PublishSubject and that's the whole circle.

The reason I did it this way, instead of binding the publish subject to the buttons' tap, is that I have to know who the sender is. Is there anyway to do so? If there isn't, is there a more intelligent design than mine in head?

Thanks!

You could use a like this filter{$0 == "A"}, if I'm understanding your design — Daniel Poulsen, Mar 23 '17 at 11:01
Filter on what stream? What is $0? I need the ViewModel to know what button was pressed in the ViewController, that's the problem :) — Yotam, Mar 23 '17 at 11:38
i think you need to add some code for me to understand the problem — Daniel Poulsen, Mar 23 '17 at 12:18

goldengil · Accepted Answer · 2017-03-27T14:19:11.873

You can make the PublishSubject to send String and then each time a button is tapped, you can send the title of the button as the event data.

publishSubject.onNext(sender.title)

That way you can distinguish the sender from the ViewModel and keep your current design.

UPDATE:

After reading your question again I realized you are trying to achieve a more reactive way than what you currently have. So instead of pulling an IBActions from all the buttons, you can just have IBOutlets and on viewDidLoad bind all those buttons to the PublishSubject. Something like this:

aButton
   .rx
   .tap.map { _ in 
      aButton.title
   }
   .bindTo(viewModel.buttonTapped)
   .disposed(by:disposeBag)

Thanks! exactly what I needed! – Yotam Mar 27 '17 at 14:11 — Yotam, Mar 27 '17 at 14:11

RxSwift: binding PublishSubject to multiple buttons and receive sender

1 Answers1