UIButton作爲子視圖編程約束

Question

我有一個UIScrollView（IBOutlet）成功約束內一個故事板。然後我以編程方式創建UIButton，並將它們作爲UIScrollView的子視圖。我如何以編程方式設置這些UIButton約束，以便它們的高度和大小與他們的超級視圖相符？

class ViewController: UIViewController { 

@IBOutlet weak var aScrollView: UIScrollView! 


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

    var xCoord: CGFloat = 5 
    let yCoord: CGFloat = 5 
    let buttonWidth:CGFloat = 100 
    let buttonHeight: CGFloat = 100 

    let gapBetweenButtons: CGFloat = 10 


    var itemCount = 0 

    // MARK: - filter buttons 
    for i in 0..<6 { 

     itemCount = i 

     let aButton = UIButton(type: .custom) 
     aButton.frame = CGRect(x: xCoord, y: yCoord, width: buttonWidth, height: buttonHeight) 
     aButton.backgroundColor = UIColor.blue 
     aButton.layer.cornerRadius = aButton.frame.size.width/2 
     aButton.clipsToBounds = true 

     xCoord += buttonWidth + gapBetweenButtons 

     aScrollView.addSubview(aButton) 
    } 
} 

Answer 1

試試這個 -

這只是關於如何編程方式添加約束的想法。

更多的瞭解，您可以點擊以下鏈接經歷 - https://developer.apple.com/reference/appkit/nslayoutanchor

let myButton = UIButton() 
self.aScrollView.addSubview(myButton) 

self.view.translatesAutoresizingMaskIntoConstraints = false 
let margins = self.view.layoutMarginsGuide 
myButton.leadingAnchor.constraint(equalTo: forView. aScrollView.leadingAnchor, constant: 5).active = true 
myButton.topAnchor.constraint(equalTo: forView. aScrollView.topAnchor, constant: 5).active = true 
myButton.heightAnchor.constraintEqualToConstant(100.0).active = true 
myButton.widthAnchor.constraintEqualToConstant(100.0).active = true 

Answer 2

你的代碼更改爲：

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

     var xCoord: CGFloat = 5 
     let yCoord: CGFloat = 5 

     let gapBetweenButtons: CGFloat = 10 


     let buttonCount = 6 
     let buttonWidth = (aScrollView.frame.width - CGFloat(buttonCount - 1) * gapBetweenButtons - xCoord - xCoord)/CGFloat(buttonCount) // - (2 * xCoord) = - (margin left + margin right). 
     let buttonHeight = buttonWidth 

     var itemCount = 0 

     // MARK: - filter buttons 
     for i in 0..<buttonCount { 

      itemCount = i 

      let aButton = UIButton(type: .custom) 
      aButton.frame = CGRect(x: xCoord, y: yCoord, width: buttonWidth, height: buttonHeight) 
      aButton.backgroundColor = UIColor.blue 
      aButton.layer.cornerRadius = aButton.frame.size.width/2 
      aButton.clipsToBounds = true 

      xCoord += buttonWidth + gapBetweenButtons 

      aScrollView.addSubview(aButton) 
     } 
    } 

Answer 3

這是如何做到這一點。我爲你製作了一個視頻教程add unbutton programmatically to scrollview in iOS, swift。請參閱鏈接。

1. 添加滾動視圖（添加約束 - >上，下，左，右）。
2. 然後添加一個視圖到你的滾動視圖（添加約束 - >上下左右，寬度， 。
3. 然後以編程方式添加按鈕及其約束。

請按照視頻教程。 add UIButton(outlet) to scrollview programmatically