IOS 小贴士

拖入Switch控件 Control拖入view controller里面
在全局定义ud

    var ud:NSUserDefaults!

    override func viewDidLoad() {        super.viewDidLoad()        // Do any additional setup after loading the view, typically from a nib.        ud = NSUserDefaults.standardUserDefaults()        mySwitch.on = ud.boolForKey("showTips")        if mySwitch.on{            UIAlertView(title: "这里是提示", message: "今天下雨了", delegate: nil, cancelButtonTitle: "OK").show()        }    }

    @IBAction func change(sender: AnyObject) {        ud.setBool(mySwitch.on, forKey: "showTips")    }