下面是一个完整的解决方案，以编程方式添加一个UIButton与targetAction。 斯威夫特2.2

override func viewDidLoad() {
  super.viewDidLoad()

  let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
  button.backgroundColor = .greenColor()
  button.setTitle("Test Button", forState: .Normal)
  button.addTarget(self, action: #selector(buttonAction), forControlEvents: .TouchUpInside)

  self.view.addSubview(button)
}

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

使用NSLayoutConstraint而不是frame来正确地为每个iPhone屏幕放置按钮可能更好。

Swift 3.1的更新代码:

override func viewDidLoad() {
  super.viewDidLoad()

  let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
  button.backgroundColor = .green
  button.setTitle("Test Button", for: .normal)
  button.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)

  self.view.addSubview(button)
}

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

Swift 4.2的更新代码:

override func viewDidLoad() {
  super.viewDidLoad()

  let button = UIButton(frame: CGRect(x: 100, y: 100, width: 100, height: 50))
  button.backgroundColor = .green
  button.setTitle("Test Button", for: .normal)
  button.addTarget(self, action: #selector(buttonAction), for: .touchUpInside)

  self.view.addSubview(button)
}

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

如果func buttonAction声明为private或internal，上述方法仍然有效。

你可以这样创建，也可以这样添加动作....

import UIKit

let myButton = UIButton(frame: CGRect(x: 0, y: 0, width: 50, height: 50))

init(nibName nibNameOrNil: String!, bundle nibBundleOrNil: NSBundle!)
{       super.init(nibName: nibName, bundle: nibBundle) 
        myButton.targetForAction("tappedButton:", withSender: self)
}

func tappedButton(sender: UIButton!)
{ 
     println("tapped button")
}

我通常会设置uibutton的扩展。斯威夫特5。

let button: UIButton = UIButton()
override func viewDidLoad() {
        super.viewDidLoad()
     button.setup(title: "OK", x: 100, y: 430, width: 220, height: 80, color: .yellow)
        buttonD.setTitleColor(.black, for: .normal)

}
extension UIButton {
    func setup(title: String, x: CGFloat, y: CGFloat, width: CGFloat, height: CGFloat, color: UIColor){
        frame = CGRect(x: x, y: y, width: width, height: height)
        backgroundColor = color
        setTitle(title , for: .normal) 
        }
    }

    // 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")
    }

你可以通过这种方式添加UIButton,UIlable和UITextfield。

UIButton代码

// var button   = UIButton.buttonWithType(UIButtonType.System) as UIButton
let button = UIButton(type: .System) // let preferred over var here
button.frame = CGRectMake(100, 100, 100, 50)
button.backgroundColor = UIColor.greenColor()
button.setTitle("Button", forState: UIControlState.Normal)
button.addTarget(self, action: "Action:", forControlEvents: UIControlEvents.TouchUpInside)
self.view.addSubview(button)

UILabel代码

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)

UITextField 代码

var txtField: UITextField = UITextField()
txtField.frame = CGRectMake(50, 70, 200, 30)
txtField.backgroundColor = UIColor.grayColor()
self.view.addSubview(txtField)

希望这对你有帮助。

将此代码添加到viewDidLoad中 / /添加按钮

            var button=UIButton(frame: CGRectMake(150, 240, 75, 30))
            button.setTitle("Next", forState: UIControlState.Normal)
            button.addTarget(self, action: "buttonTapAction:", forControlEvents: UIControlEvents.TouchUpInside)
            button.backgroundColor = UIColor.greenColor()
            self.view.addSubview(button)

将这个函数写在它的外面，当你点击按钮时，这个函数将被调用

func buttonTapAction(sender:UIButton!)
{
    println("Button is working")
}