Swift3.0之UITableViewCell系统样式

//
//  ViewController.Swift
//  Swift demo - UITableViewCell system style
//
//  Created by 柯其谱 on 17/3/13.
//  Copyright © 2017年 柯其谱. All rights reserved.
//

import UIKit

//MARK: View life cycle
class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        self.setupSubviews()
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

//MARK: Setup
extension ViewController {
    fileprivate func setupSubviews() -> Void {
        self.setupTableView()
    }
    
    private func setupTableView() -> Void {
        let tableView = UITableView (frame: self.view.frame, style: UITableViewStyle.grouped)
        tableView.delegate = self
        tableView.dataSource = self
        self.view.addSubview(tableView)
    }
}

//MARK: UITableViewDelegate
extension ViewController: UITableViewDelegate, UITableViewDataSource {
    func numberOfSections(in tableView: UITableView) -> Int {
        return 4
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return 1
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        var cellId: String
        var cell: UITableViewCell? = nil
        var style: UITableViewCellStyle
        let image = UIImage (named: "cellImage")
        var text: String
        let detailText = "detail_text"
        switch indexPath.section {
        case 0:
            cellId = "default"
            style = UITableViewCellStyle.default
            text = "default_text"
        case 1:
            cellId = "subtitle"
            style = UITableViewCellStyle.subtitle
            text = "subtitle_text"
        case 2:
            cellId = "value1"
            style = UITableViewCellStyle.value1
            text = "value1_text"
        default:
            cellId = "value2"
            style = UITableViewCellStyle.value2
            text = "value2_text"
        }
        cell = tableView.dequeueReusableCell(withIdentifier: cellId)
        if cell == nil {
            cell = UITableViewCell (style: style, reuseIdentifier: cellId)
        }
        cell?.imageView?.image = image
        cell?.textLabel?.text = text
        cell?.detailTextLabel?.text = detailText
        cell?.accessoryType = UITableViewCellAccessoryType.disclosureIndicator
        return cell!
    }
}