// UILabel:
    let label = UILabel()
    label.frame = CGRectMake(35, 100, 250, 30)
    label.textColor = UIColor.blackColor()
    label.textAlignment = NSTextAlignment.Center
    label.text = "Hello World"
    self.view.addSubview(label)

    // UIButton:
    let btn: UIButton = UIButton(type: UIButtonType.Custom) as UIButton
    btn.frame = CGRectMake(130, 70, 60, 20)
    btn.setTitle("Click", forState: UIControlState.Normal)
    btn.setTitleColor(UIColor.blackColor(), forState: .Normal)
    btn.addTarget(self, action:Selector("clickAction"), forControlEvents: UIControlEvents.TouchUpInside)
    view.addSubview(btn)


    // Button Action:
    @IBAction func clickAction(sender:AnyObject)
    {
        print("Click Action")
    }

    // UILabel:
    let label = UILabel()
    label.frame = CGRectMake(35, 100, 250, 30)
    label.textColor = UIColor.blackColor()
    label.textAlignment = NSTextAlignment.Center
    label.text = "Hello World"
    self.view.addSubview(label)

    // UIButton:
    let btn: UIButton = UIButton(type: UIButtonType.Custom) as UIButton
    btn.frame = CGRectMake(130, 70, 60, 20)
    btn.setTitle("Click", forState: UIControlState.Normal)
    btn.setTitleColor(UIColor.blackColor(), forState: .Normal)
    btn.addTarget(self, action:Selector("clickAction"), forControlEvents: UIControlEvents.TouchUpInside)
    view.addSubview(btn)


    // Button Action:
    @IBAction func clickAction(sender:AnyObject)
    {
        print("Click Action")
    }

Uilabel code 

var label: UILabel = UILabel()
label.frame = CGRectMake(50, 50, 200, 21)
label.backgroundColor = UIColor.blackColor()
label.textColor = UIColor.whiteColor()
label.textAlignment = NSTextAlignment.Center
label.text = "test label"
self.view.addSubview(label)

这对我来说非常好，#DynamicButtonEvent #IOS #Swift #Xcode

func setupButtonMap(){
    let mapButton = UIButton(type: .system)
    mapButton.setImage(#imageLiteral(resourceName: "CreateTrip").withRenderingMode(.alwaysOriginal), for: .normal)
    mapButton.frame = CGRect(x: 0, y: 0, width: 34, height: 34)
    mapButton.contentMode = .scaleAspectFit
    mapButton.backgroundColor = UIColor.clear
    mapButton.addTarget(self, action: #selector(ViewController.btnOpenMap(_:)), for: .touchUpInside)
    navigationItem.leftBarButtonItem = UIBarButtonItem(customView: mapButton)
    }
@IBAction func btnOpenMap(_ sender: Any?) {
    print("Successful")
}

Swift 5和Swift 4一样

 let button = UIButton()
 button.frame = CGRect(x: self.view.frame.size.width - 60, y: 60, width: 50, height: 50)
 button.backgroundColor = UIColor.red
 button.setTitle("Name your Button ", for: .normal)
 button.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)
 self.view.addSubview(button)

 @objc func buttonAction(sender: UIButton!) {
    print("Button tapped")
 }

Swift:以编程方式创建Ui按钮

let myButton = UIButton()

myButton.titleLabel!.frame = CGRectMake(15, 54, 300, 500)
myButton.titleLabel!.text = "Button Label"
myButton.titleLabel!.textColor = UIColor.redColor()
myButton.titleLabel!.textAlignment = .Center
self.view.addSubview(myButton)