func clickButton1(){

创建uialertcontroller

        var alertCtl : UIAlertController = UIAlertController(title: "Alert", message: "You clicked button1", preferredStyle: UIAlertControllerStyle.Alert)

添加action到uialertcontroller，action是UIalertcontroller上的按钮操作，建议至少添加一个，如果不添加，alertcontroller就没有相应的按钮退出

        var alertAction : UIAlertAction = UIAlertAction(title: "Action", style: UIAlertActionStyle.Default, handler: { (param : UIAlertAction!) -> Void in

            println("I am alert action")

            var position = self.view.center.x

        })

        alertCtl.addAction(alertAction)

显示alert controller

        self.presentViewController(alertCtl, animated: true, completion: nil)

        /*var alertView : UIAlertView = UIAlertView(frame: CGRect(origin: CGPoint(x: 50, y: 200), size: CGSize(width: 100, height: 40)))

        alertView.title = "Button1"

        alertView.message = "You clicked button1!"

        alertView.addButtonWithTitle("Confirm")

        alertView.delegate = self

        alertView.show()*/

    }