ViewModel Example with Rx

ViewModelMVVMRx.swift

import Foundation
import RxSwift
import RxCocoa

class ViewModel {

	private let imageRelay: BehaviorRelay<UIImage?> = BehaviorRelay(value: nil)
	private let labelTextRelay: BehaviorRelay<String?> = BehaviorRelay(value: nil)

	var buttonTapRelay = PublishRelay<Void>()

	private let disposeBag = DisposeBag()
	private let model: [Model]

	private var position = 0

	var imageDriver: Driver<UIImage?> {
		return self.imageRelay.asDriver()
	}

	var labelDriver: Driver<String?> {
		return self.labelTextRelay.asDriver()
	}

	init(model: [Model]) {
		self.model = model

		self.createSubscription()

		self.imageRelay.accept(model[0].image)
		self.labelTextRelay.accept(model[0].text)
	}

	private func createSubscription() {
		self.buttonTapRelay.subscribe(onNext: { _ in
			self.position = self.position + 1 >= self.model.count ? 0 : self.position + 1
			self.imageRelay.accept(self.model[self.position].image)
			self.labelTextRelay.accept(self.model[self.position].text)
		}).disposed(by: self.disposeBag)
	}
}