ios 在 Swift 中以编程方式制作 UIButton

Make a UIButton programmatically in Swift

提问by Benr783

I am trying to build UI's programmatically. How do I get this action working? I am developing with Swift.

我正在尝试以编程方式构建 UI。我如何让这个动作起作用？我正在用 Swift 开发。

Code in viewDidLoad:

viewDidLoad 中的代码：

override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.
        let myFirstLabel = UILabel()
        let myFirstButton = UIButton()
        myFirstLabel.text = "I made a label on the screen #toogood4you"
        myFirstLabel.font = UIFont(name: "MarkerFelt-Thin", size: 45)
        myFirstLabel.textColor = UIColor.redColor()
        myFirstLabel.textAlignment = .Center
        myFirstLabel.numberOfLines = 5
        myFirstLabel.frame = CGRectMake(15, 54, 300, 500)
        myFirstButton.setTitle("?", forState: .Normal)
        myFirstButton.setTitleColor(UIColor.blueColor(), forState: .Normal)
        myFirstButton.frame = CGRectMake(15, -50, 300, 500)
        myFirstButton.addTarget(self, action: "pressed", forControlEvents: .TouchUpInside)
        self.view.addSubview(myFirstLabel)
        self.view.addSubview(myFirstButton)
    }

        func pressed(sender: UIButton!) {
            var alertView = UIAlertView();
            alertView.addButtonWithTitle("Ok");
            alertView.title = "title";
            alertView.message = "message";
            alertView.show();
        }

回答by Dash

You're just missing the colon at the end of the selector name. Since pressed takes a parameter the colon must be there. Also your pressed function shouldn't be nested inside viewDidLoad.

您只是缺少选择器名称末尾的冒号。由于 press 需要一个参数，所以冒号必须在那里。此外，您按下的函数不应嵌套在 viewDidLoad 中。

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    let myFirstLabel = UILabel()
    let myFirstButton = UIButton()
    myFirstLabel.text = "I made a label on the screen #toogood4you"
    myFirstLabel.font = UIFont(name: "MarkerFelt-Thin", size: 45)
    myFirstLabel.textColor = UIColor.redColor()
    myFirstLabel.textAlignment = .Center
    myFirstLabel.numberOfLines = 5
    myFirstLabel.frame = CGRectMake(15, 54, 300, 500)
    myFirstButton.setTitle("?", forState: .Normal)
    myFirstButton.setTitleColor(UIColor.blueColor(), forState: .Normal)
    myFirstButton.frame = CGRectMake(15, -50, 300, 500)
    myFirstButton.addTarget(self, action: #selector(myClass.pressed(_:)), forControlEvents: .TouchUpInside)
    self.view.addSubview(myFirstLabel)
    self.view.addSubview(myFirstButton)
}

@objc func pressed(sender: UIButton!) {
    var alertView = UIAlertView()
    alertView.addButtonWithTitle("Ok")
    alertView.title = "title"
    alertView.message = "message"
    alertView.show()
}

EDIT: Updated to reflect best practices in Swift 2.2. #selector() should be used rather than a literal string which is deprecated.

编辑：更新以反映 Swift 2.2 中的最佳实践。应该使用 #selector() 而不是不推荐使用的文字字符串。

回答by n.by.n

Swift 2.2 Xcode 7.3

斯威夫特 2.2 Xcode 7.3

Since Objective-C String Literals are deprecated now for button callback methods

由于现在不推荐使用 Objective-C 字符串文字用于按钮回调方法

let button:UIButton = UIButton(frame: CGRectMake(100, 400, 100, 50))
button.backgroundColor = UIColor.blackColor()
button.setTitle("Button", forState: UIControlState.Normal)
button.addTarget(self, action:#selector(self.buttonClicked), forControlEvents: .TouchUpInside)
self.view.addSubview(button)

func buttonClicked() {
     print("Button Clicked")
}

Swift 3 Xcode 8

斯威夫特 3 Xcode 8

let button:UIButton = UIButton(frame: CGRect(x: 100, y: 400, width: 100, height: 50))
button.backgroundColor = .black
button.setTitle("Button", for: .normal)
button.addTarget(self, action:#selector(self.buttonClicked), for: .touchUpInside)
self.view.addSubview(button)

func buttonClicked() {
    print("Button Clicked")
}

Swift 4 Xcode 9

斯威夫特 4 Xcode 9

let button:UIButton = UIButton(frame: CGRect(x: 100, y: 400, width: 100, height: 50))
button.backgroundColor = .black
button.setTitle("Button", for: .normal)
button.addTarget(self, action:#selector(self.buttonClicked), for: .touchUpInside)
self.view.addSubview(button)

@objc func buttonClicked() {
    print("Button Clicked")
}

回答by JP Aquino

Swift 4/5

斯威夫特 4/5

let button = UIButton(frame: CGRect(x: 20, y: 20, width: 200, height: 60))
 button.setTitle("Email", for: .normal)
 button.backgroundColor = .white
 button.setTitleColor(UIColor.black, for: .normal)
 button.addTarget(self, action: #selector(self.buttonTapped), for: .touchUpInside)
 myView.addSubview(button)



@objc func buttonTapped(sender : UIButton) {
                //Write button action here
            }

回答by Raman

Swift 4

斯威夫特 4

    private func createButton {
        let sayButtonT = UIButton(type: .custom)
        sayButtonT.addTarget(self, action: #selector(sayAction(_:)), for: .touchUpInside)
    }

    @objc private func sayAction(_ sender: UIButton?) {

    }

回答by Raman

Yeah in simulator. Some times it wont recognise the selector there is a bug it seems. Even i faced not for your code , then i just changed the action name (selector). It works

是的在模拟器中。有时它不会识别选择器似乎有一个错误。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）。有用

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)

An example selector function is here:

一个示例选择器函数在这里：

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

回答by samatron

You should be able to create a customize UI button programmatically by accessing the titleLabelproperty of UIButton.

您应该能够通过访问UIButton的titleLabel属性以编程方式创建自定义 UI 按钮。

Per Class Referencein Swift: Regarding the titleLabelproperty, it says that "although this property is read-only, its own properties are read/write. Use these properties primarily to configure the text of the button."

Swift 中的Per Class Reference：关于titleLabel属性，它说“虽然这个属性是只读的，但它自己的属性是读/写的。主要使用这些属性来配置按钮的文本。”

In Swift, you can directly modify the properties of titleLabel like such:

在Swift 中，您可以像这样直接修改 titleLabel 的属性：

let myFirstButton = UIButton()
myFirstButton.titleLabel!.text = "I made a label on the screen #toogood4you"
myFirstButton.titleLabel!.font = UIFont(name: "MarkerFelt-Thin", size: 45)
myFirstButton.titleLabel!.textColor = UIColor.red
myFirstButton.titleLabel!.textAlignment = .center
myFirstButton.titleLabel!.numberOfLines = 5
myFirstButton.titleLabel!.frame = CGRect(x: 15, y: 54, width: 300, height: 500)

Edit

编辑

Swift 3.1 Syntax

Swift 3.1 语法

回答by krushnsinh

try these..i hope it helps...

试试这些……我希望它有帮助……

override func viewDidLoad() {
super.viewDidLoad()  

    let btn = UIButton()
    btn.frame = CGRectMake(10, 10, 50, 50)  //set frame
    btn.setTitle("btn", forState: .Normal)  //set button title
    btn.setTitleColor(UIColor.redColor(), forState: .Normal) //set button title color
    btn.backgroundColor = UIColor.greenColor() //set button background color
    btn.tag = 1 // set button tag
    btn.addTarget(self, action: "btnclicked:", forControlEvents: .TouchUpInside) //add button action
    self.view.addSubview(btn) //add button in view

}

these is buttons click event..

这些是按钮点击事件..

func btnclicked(sender: UIButton!) 
{
    //write the task you want to perform on buttons click event..
}

回答by phitsch

Swift 3: You can create a UIButtonprogrammatically

Swift 3：您可以以UIButton编程方式创建

either inside a methods scope for example in ViewDidLoad()Be sure to add constraints to the button, otherwise you wont see it

要么在方法范围内，例如在ViewDidLoad()一定要向按钮添加约束，否则你不会看到它

let button = UIButton()
button.translatesAutoresizingMaskIntoConstraints = false
button.target(forAction: #selector(buttonAction), withSender: self)
//button.backgroundColor etc

view.addSubview(button)

func buttonAction() {
   //some Action
}

or outside your scope as global variable to access it from anywhere in your module

或在您的范围之外作为全局变量从您的任何地方访问它 module

let button: UIButton = {
   let b = UIButton()
   b.translatesAutoresizingMaskIntoConstraints = false
   //b.backgroundColor etc
   return b
}()

and then you setup the constraints

然后你设置约束

func setupButtonView() {
   view.addSubview(button)
   button.widthAnchor.constraint(equalToConstant: 40).isActive = true
   button.heightAnchor.constraint(equalToConstant: 40).isActive = true
   // etc

}

回答by Ted van Gaalen

Swift "Button factory" extension for UIButton (and while we're at it) also for UILabel like so:

UIButton 的 Swift“按钮工厂”扩展（当我们在做的时候）也适用于 UILabel，如下所示：

extension UILabel
{
// A simple UILabel factory function
// returns instance of itself configured with the given parameters

// use example (in a UIView or any other class that inherits from UIView):

//   addSubview(   UILabel().make(     x: 0, y: 0, w: 100, h: 30,
//                                   txt: "Hello World!",
//                                 align: .center,
//                                   fnt: aUIFont,
//                              fntColor: UIColor.red)                 )
//

func make(x: CGFloat, y: CGFloat, w: CGFloat, h: CGFloat,
          txt: String,
          align: NSTextAlignment,
          fnt: UIFont,
          fntColor: UIColor)-> UILabel
{
    frame = CGRect(x: x, y: y, width: w, height: h)
    adjustsFontSizeToFitWidth = true
    textAlignment = align
    text = txt
    textColor = fntColor
    font = fnt
    return self
}
// Of course, you can make more advanced factory functions etc.
// Also one could subclass UILabel, but this seems to be a     convenient case for an extension.
}


extension UIButton
{
// UIButton factory returns instance of UIButton
//usage example:

// addSubview(UIButton().make(x: btnx, y:100, w: btnw, h: btnh,
// title: "play", backColor: .red,
// target: self,
// touchDown: #selector(play), touchUp: #selector(stopPlay)))


func make(   x: CGFloat,y: CGFloat,
             w: CGFloat,h: CGFloat,
                  title: String, backColor: UIColor,
                  target: UIView,
                  touchDown:  Selector,
                  touchUp:    Selector ) -> UIButton
{
    frame = CGRect(x: x, y: y, width: w, height: h)
    backgroundColor = backColor
    setTitle(title, for: .normal)
    addTarget(target, action: touchDown, for: .touchDown)
    addTarget(target, action: touchUp  , for: .touchUpInside)
    addTarget(target, action: touchUp  , for: .touchUpOutside)

    return self
}
}

Tested in Swift in Xcode Version 9.2 (9C40b) Swift 4.x

在 Xcode 版本 9.2 (9C40b) Swift 4.x 中在 Swift 中测试

回答by Ananthu R Krishnan

Swift: Ui Button create programmatically,

Swift：Ui Button 以编程方式创建，

var button: UIButton = UIButton(type: .Custom)

button.frame = CGRectMake(80.0, 210.0, 160.0, 40.0)

button.addTarget(self, action: #selector(self.aMethod), forControlEvents: .TouchUpInside)

button.tag=2

button.setTitle("Hallo World", forState: .Normal)

view.addSubview(button)


func aMethod(sender: AnyObject) {
    print("you clicked on button \(sender.tag)")
}