使用UIAlertController弹出消息框

//
//  ViewController.swift
//  HelloWord
//
//  Created by QHS8848 on 15/9/29.
//  Copyright © 2015年 QHS8848. All rights reserved.
//

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        //设置背景色为白色
        self.view.backgroundColor = UIColor.whiteColor()
    }

    @IBAction func buttonClick1(sender: UIButton) {
        
        //alertController--Alert模式
        let alertController = UIAlertController(title: "AlertController", message: "使用UIAlertController来作提示对话框的测试", preferredStyle:.Alert)
        
        //OK按钮的代码块，这里点击Ok按钮之后，再次弹出一个新的Alert
        let okActionHandler = {(action:UIAlertAction!)->Void in
            let alertMessage = UIAlertController(title: "AlertAction", message: "你点击的是Ok按钮", preferredStyle: .Alert)
            alertMessage.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.Default, handler: nil))
            self.presentViewController(alertMessage, animated: true, completion: nil)
        }
        
        //OKButton
        let okAction = UIAlertAction(title: "OK", style: .Default, handler: okActionHandler)
        
        //Cancel按钮的事件处理代码块
        let cancelActionHander = {(action:UIAlertAction!) -> Void in
            NSLog(" Cancel Button")
        }

        //CancelButton
        let cancelAction = UIAlertAction(title: "Cancel", style: .Default, handler: cancelActionHander)
        
        //将UIAlertAction添加到UIAlertController上面
        alertController.addAction(okAction)
        alertController.addAction(cancelAction)
        
        //显示
        presentViewController(alertController, animated: true, completion: nil)
    }
    
    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
    }
}