步骤1:创建一个新项目

步骤2:在ViewController.swift中

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // CODE
        let btn = UIButton(type: UIButtonType.System) as UIButton        
        btn.backgroundColor = UIColor.blueColor()
        btn.setTitle("CALL TPT AGENT", forState: UIControlState.Normal)
        btn.frame = CGRectMake(100, 100, 200, 100)
        btn.addTarget(self, action: "clickMe:", forControlEvents: UIControlEvents.TouchUpInside)
        self.view.addSubview(btn)

    }

    func clickMe(sender:UIButton!) {
      print("CALL")
    }

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


}

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")
 }

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")
}

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)

是的，在模拟器里。有时它不会识别选择器，这似乎是一个错误。即使我面对的不是你的代码，然后我只是改变了动作名称(选择器)。它的工作原理

let buttonPuzzle:UIButton = UIButton(frame: CGRectMake(100, 400, 100, 50))
buttonPuzzle.backgroundColor = UIColor.greenColor()
buttonPuzzle.setTitle("Puzzle", forState: UIControlState.Normal)
buttonPuzzle.addTarget(self, action: "buttonAction:", forControlEvents: UIControlEvents.TouchUpInside)
buttonPuzzle.tag = 22;
self.view.addSubview(buttonPuzzle)

选择器函数在这里:

func buttonAction(sender:UIButton!)
{

    var btnsendtag:UIButton = sender
    if btnsendtag.tag == 22 {            
        //println("Button tapped tag 22")
    }
}

override func viewDidLoad() {

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

    var imageView = UIImageView(frame: CGRectMake(100, 150, 150, 150));
    var image = UIImage(named: "BattleMapSplashScreen.png");
    imageView.image = image;
    self.view.addSubview(imageView);

}