TableViewBinding.swift

import UIKit
import ReactiveCocoa

protocol Bindable {
    func bind<T>(viewModel: T)
}

class TableViewBinding<T, E: ErrorType> {
    
    //MARK: Properties
    
    private let tableView: UITableView
    private let dataSource: TableViewDataSource<T>

    //MARK: Public API
    
    init(tableView _tableView: UITableView, sourceSignal: SignalProducer<[T], E>, resuseIdentifier: String, selectionCommand: Action<T, Void, NoError>? = nil) {
        tableView = _tableView
        dataSource = TableViewDataSource(reuseIdentifier: resuseIdentifier, selectionCommand: selectionCommand)
        
        tableView.dataSource = dataSource
        tableView.delegate = dataSource
    
        sourceSignal.on(next: { value in
            self.dataSource.data.put(value)
            self.tableView.reloadData()
        }).start()
    }
}

class TableViewDataSource<T>: NSObject, UITableViewDataSource, UITableViewDelegate {
    
    private let reuseIdentifier: String
    private let selectionCommand: Action<T, Void, NoError>?

    let data = MutableProperty([T]())
    
    init(reuseIdentifier _reuseIdentifier: String, selectionCommand _selectionCommand: Action<T, Void, NoError>? = nil) {
        reuseIdentifier = _reuseIdentifier
        selectionCommand = _selectionCommand
    }
    
    //MARK: Datasource Methods
    
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return data.value.count
    }
    
    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        
        let cell = tableView.dequeueReusableCellWithIdentifier(self.reuseIdentifier, forIndexPath: indexPath)
        let item = data.value[indexPath.row]
        
        if let reactiveView = cell as? Bindable {
            reactiveView.bind(item)
        }
        
        return cell
    }
    
    //MARK: Delegate methods
    
    func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
        return 44
    }
    
    func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
        
        guard let selectionCommand = selectionCommand else {
            tableView.deselectRowAtIndexPath(indexPath, animated: true)
            return
        }
        
        let item = data.value[indexPath.row]
        selectionCommand
            .apply(item)
            .on(completed: { tableView.deselectRowAtIndexPath(indexPath, animated: true) })
            .start()
    }
}