我如何以编程方式创建图形元素(如UIButton)在Swift?我试图创建和添加按钮到一个视图,但不能。


当前回答

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")
}

其他回答

这是可能的。除了使用swift语法之外,您几乎可以以相同的方式完成所有操作。例如,你可以用这样的代码创建一个UIButton:

 var button: UIButton = UIButton(frame: CGRectMake(0, 0, 100, 100))

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")
}

API没有改变——只有语法改变了。你可以创建一个UIButton并像这样添加它:

var button = UIButton(frame: CGRectMake(0, 0, 50, 50))
self.view.addSubview(button) // assuming you're in a view controller

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")
 }

斯威夫特3

let btn = UIButton(type: .custom) as UIButton
btn.backgroundColor = .blue
btn.setTitle("Button", for: .normal)
btn.frame = CGRect(x: 100, y: 100, width: 200, height: 100)
btn.addTarget(self, action: #selector(clickMe), for: .touchUpInside)
self.view.addSubview(btn)

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

输出