Easy way to populate UIView properties with data.

ViewAdapter.swift

//
//  ViewAdapter.swift
//
//  Created by Valerio Mazzeo on 10/08/2016.
//  Copyright © 2016 Valerio Mazzeo. All rights reserved.
//

import UIKit

/**
 Types adopting the `ViewAdapter` protocol provides a way to feed data from a `Model` to a `View`.
 This is particularly useful for `UITableViewCell` and `UICollectionViewCell` cells which have to be populated by a data source.

 
 Adapter as struct:

 ```
 struct MyCellStoreAdapter: ViewAdapter {
    func configure(view: MyCell, with element: Store) -> Void {
        view.textLabel?.text = element.name
    }
 }
 ```

 Adapter as nested struct in the cell
 
 ```
 extension MyCell {
    public struct StoreAdapter: ViewAdapter {
        public func configure(view: MyCell, with element: Store) -> Void {
            view.textLabel?.text = element.name
        }
    }
 }
 ```
 
 Adapter as computed cell static property using `AnyViewAdapter`

 ```
 extension MyCell {
    public static var storeAdapter: AnyViewAdapter<MyCell, Store> {
        return AnyViewAdapter { view, element in
            view.textLabel?.text = element.name
        }
    }
 }
 ```
 
 Adapter as nested computed cell static property using `AnyViewAdapter`

 ```
 extension MyCell {
  public struct Adapter {
    public static var store: AnyViewAdapter<MyCell, Store> {
        return AnyViewAdapter { view, element in
            view.textLabel?.text = element.name
        }
    }
  }
 }
 ```
 */
public protocol ViewAdapter {

    associatedtype ViewType: UIView

    associatedtype Model

    func configure(view: ViewType, with element: Model) -> Void
}

public struct AnyViewAdapter<V: UIView, M>: ViewAdapter {

    public typealias ViewType = V

    public typealias Model = M

    private let body: (view: ViewType, element: Model) -> Void

    /**
     Creates a `ViewAdapter` instance whose `configure` method invokes
     `body`.
     */
    public init(body: (view: ViewType, element: Model) -> Void) {
        self.body = body
    }

    public func configure(view: ViewType, with element: Model) -> Void {
        self.body(view: view, element: element)
    }
}