SyncStepCell.swift

import Foundation
import UIKit
import RxSwift

class SyncStepCell: UITableViewCell {
    static let reuseIdentifier = "SyncStepCell"
    
    @IBOutlet private weak var titleLabel: UILabel!
    @IBOutlet private weak var activityIndicator: UIActivityIndicatorView!
    @IBOutlet private weak var checkmarkImage: UIImageView!
    
    var disposeBag = DisposeBag()
    
    var viewModel: SyncStepViewModel? {
        didSet {
            if let vm = viewModel {
                vm.isRunning.asObservable().map({!$0}).bindTo(activityIndicator.rx.isHidden).disposed(by: disposeBag)
                vm.isRunning.asObservable().map({$0 ? UIColor.black : UIColor.gray}).bindTo(titleLabel.rx.textColor).disposed(by: disposeBag)
                vm.stepTitle.bindTo(titleLabel.rx.text).disposed(by: disposeBag)
                vm.isRunning.asObservable().bindTo(checkmarkImage.rx.isHidden).disposed(by: disposeBag)
            }
        }
    }
}

SyncStepViewModel.swift

import Foundation
import RxSwift

class SyncStepViewModel {
    let isRunning = Variable(true)
    let percentComplete = Variable<Int>(0)
    let stepTitle: Observable<String>
    
    private let title: String
    
    init(title: String) {
        self.title = title
        
        stepTitle = Observable.combineLatest(isRunning.asObservable(), percentComplete.asObservable()) {
            (running: Bool, percent: Int) -> String in if (running && percent>0) {
                return "\(title) \(percent)%"
            } else {
                return title
            }
        }
    }
}

SyncViewController.swift

viewModel.syncSteps.asObservable()
            .bindTo(syncStepsTableView.rx.items(cellIdentifier: SyncStepCell.reuseIdentifier, cellType: UITableViewCell.self)) { (row, element, cell) in
                if let cell = cell as? SyncStepCell {
                    cell.viewModel = element
                }
            }
            .disposed(by: disposeBag)

SyncViewModel.swift

import Foundation
import RxSwift

class SyncViewModel {
    let syncSteps = Variable<[SyncStepViewModel]>([])
}