swift - 使用按钮在 swift 中切换语句

Question

我无法弄清楚如何在 swift 中使用我的 switch 语句，以便当我单击任一按钮时它将执行 println()。每次我单击任一按钮时，它都会执行默认值。

class ViewController: UIViewController{

    var addOne : UIButton = UIButton(frame: CGRectMake(0, 0, 40, 40))
    var addFive : UIButton = UIButton(frame: CGRectMake(0, 0, 40, 40))

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

        addOne.setTitle("+1", forState: UIControlState.Normal)
        addOne.backgroundColor = UIColor.blackColor()
        addOne.center = (CGPointMake(40, 250))
        addOne.addTarget(self, action: "player", forControlEvents: UIControlEvents.TouchUpInside)
        view.addSubview(addOne)

        addFive.setTitle("+5", forState: UIControlState.Normal)
        addFive.backgroundColor = UIColor.blackColor()
        addFive.center = (CGPointMake(200, 250))
        addFive.addTarget(self, action: "player", forControlEvents: UIControlEvents.TouchUpInside)
        view.addSubview(addFive)
    }

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

    func player(){

        switch (true){

        case addOne:
            println("goodbye")
        case addFive:
            println("hello world")

        default:
            println("hello")
        }

    }

}

Answer 1

更改此:

addOne.addTarget(self, action: "player", forControlEvents: UIControlEvents.TouchUpInside)

对此:

addOne.addTarget(self, action: "player:", forControlEvents: UIControlEvents.TouchUpInside)

还有这个:

addFive.addTarget(self, action: "player", forControlEvents: UIControlEvents.TouchUpInside)

对此:

addFive.addTarget(self, action: "player:", forControlEvents: UIControlEvents.TouchUpInside)

注意“player:”中添加的冒号

下一步，更改此:

func player(){

    switch (true){

    case addOne:
        println("goodbye")
    case addFive:
        println("hello world")

    default:
        println("hello")
    }

}

对此:

func player(sender: UIButton){

    switch (sender){

    case addOne:
        println("goodbye")
    case addFive:
        println("hello world")

    default:
        println("hello")
    }

}