SWIFT UITableView的基本用法

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
        self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
        // Override point for customization after application launch.
        self.window!.backgroundColor = UIColor.whiteColor()

        let navigation = UINavigationController(rootViewController: RootViewController())
        self.window?.rootViewController = navigation

        self.window!.makeKeyAndVisible()
        return true
    }

}

import UIKit

class RootViewController: UIViewController {

    override func loadView() {
        super.loadView()
        //初始化UITableView
        let tableView = UITableView()
        tableView.frame = UIScreen.mainScreen().bounds
        tableView.dataSource = self
        tableView.delegate = self
        self.view.addSubview(tableView)
    }
    //懒加载数据
    lazy var datas:[String] = {
        return ["是雨是泪","分分钟需要你","伤心太平洋","曾经最痛","飘雪"]
    }()

    override func viewDidLoad() {
        super.viewDidLoad()
        self.title = "UITableView的基本用法"
    }
}

extension RootViewController:UITableViewDelegate,UITableViewDataSource
{
    //区的个数
    func numberOfSectionsInTableView(tableView: UITableView) -> Int {
        return
    }
    //在相应区中cell的个数
    func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return datas.count
    }
    // cell的高度
    func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
        return
    }

    func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
        //在重用机制里取出cell
        var cell = tableView.dequeueReusableCellWithIdentifier("cell")
        //如果cell为空则创建
        if cell == nil {
            cell = UITableViewCell(style: UITableViewCellStyle.Default, reuseIdentifier: "cell")
        }
        //设置数据
        cell?.textLabel?.text = datas[indexPath.row]
        return cell!
    }

}