swift版本hello

import UIKit

class ViewController: UIViewController {
    
    @IBOutlet var button : UIButton?
    //var alertView:UIAlertView?

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

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

    @IBAction func buttonPressed(sender : AnyObject) {
        NSLog(button!.titleLabel!.text!)
        var alertView : UIAlertView = UIAlertView(title: "Are You Sure", message: "Look This", delegate: nil, cancelButtonTitle: "OK")
        alertView.show()
    }
}

连接有两处：

1. 设计视图和代码声明的按钮定义的连接

2. 设计视图的按钮点击事件和代码的函数之间的连接

用辅助视图同时打开代码文件和视图，按住control拖拽按钮到代码，可以分别建立相应的连接