详细阐述Mundi的回答。

例如，在UIView中嵌入一个标签，并通过自动布局强制填充。例子:

概述:

创建一个UIView(面板)，并设置它的外观。 创建一个UILabel并将其添加到面板中。 添加约束以强制填充。 将面板添加到视图层次结构中，然后定位面板。

细节:

创建面板视图。 let panel = UIView() 面板。backgroundColor = .green panel.layer.cornerRadius = 12 创建标签，将其作为子视图添加到面板。 let label = UILabel() panel.addSubview(标签) 在标签的边缘和面板之间添加约束。这迫使面板与标签保持一定距离。也就是说,“填充”。

编辑:手工完成所有这些是超级乏味、冗长和容易出错的。我建议你从GitHub中选择一个自动布局包装器或自己写一个

label.panel.translatesAutoresizingMaskIntoConstraints = false
label.topAnchor.constraint(equalTo: panel.topAnchor,
    constant: vPadding).isActive = true
label.bottomAnchor.constraint(equalTo: panel.bottomAnchor,
    constant: -vPadding).isActive = true
label.leadingAnchor.constraint(equalTo: panel.leadingAnchor,
    constant: hPadding).isActive = true
label.trailingAnchor.constraint(equalTo: panel.trailingAnchor,
    constant: -hPadding).isActive = true

label.textAlignment = .center

将面板添加到视图层次结构中，然后添加定位约束。例如，拥抱tableViewCell的右侧，如示例图像中所示。

注意:您只需要添加位置约束，而不是尺寸约束:Auto Layout将基于标签的intrinsicContentSize和前面添加的约束来解决布局问题。

hostView.addSubview(panel)
panel.translatesAutoresizingMaskIntoConstraints = false
panel.trailingAnchor.constraint(equalTo: hostView.trailingAnchor,
    constant: -16).isActive = true
panel.centerYAnchor.constraint(equalTo: hostView.centerYAnchor).isActive = true

子类UILabel。(File-New-File- CocoaTouchClass-make UILabel的子类)。

//  sampleLabel.swift

import UIKit

class sampleLabel: UILabel {

 let topInset = CGFloat(5.0), bottomInset = CGFloat(5.0), leftInset = CGFloat(8.0), rightInset = CGFloat(8.0)

 override func drawTextInRect(rect: CGRect) {

  let insets: UIEdgeInsets = UIEdgeInsets(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
  super.drawTextInRect(UIEdgeInsetsInsetRect(rect, insets))

 }
 override func intrinsicContentSize() -> CGSize {
  var intrinsicSuperViewContentSize = super.intrinsicContentSize()
  intrinsicSuperViewContentSize.height += topInset + bottomInset
  intrinsicSuperViewContentSize.width += leftInset + rightInset
  return intrinsicSuperViewContentSize
 }
}

ViewController:

override func viewDidLoad() {
  super.viewDidLoad()

  let labelName = sampleLabel(frame: CGRectMake(0, 100, 300, 25))
  labelName.text = "Sample Label"
  labelName.backgroundColor =  UIColor.grayColor()

  labelName.textColor = UIColor.redColor()
  labelName.shadowColor = UIColor.blackColor()
  labelName.font = UIFont(name: "HelveticaNeue", size: CGFloat(22))
  self.view.addSubview(labelName)
 }

或者将Storyboard上的自定义UILabel类关联为Label的类。

只需使用一个UIView作为一个superview，并定义一个固定的边距标签与自动布局。

斯威夫特4

易于使用的解决方案，可用于项目中的所有UILabel子。

例子:

let label = UILabel()
    label.<Do something>
    label.padding = UIEdgeInsets(top: 0, left: 16, bottom: 0, right: 0)

UILabel扩展

import UIKit

extension UILabel {
    private struct AssociatedKeys {
        static var padding = UIEdgeInsets()
    }

    public var padding: UIEdgeInsets? {
        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.padding) as? UIEdgeInsets
        }
        set {
            if let newValue = newValue {
                objc_setAssociatedObject(self, &AssociatedKeys.padding, newValue as UIEdgeInsets?, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN_NONATOMIC)
            }
        }
    }

    override open func draw(_ rect: CGRect) {
        if let insets = padding {
            self.drawText(in: rect.inset(by: insets))
        } else {
            self.drawText(in: rect)
        }
    }

    override open var intrinsicContentSize: CGSize {
        guard let text = self.text else { return super.intrinsicContentSize }

        var contentSize = super.intrinsicContentSize
        var textWidth: CGFloat = frame.size.width
        var insetsHeight: CGFloat = 0.0
        var insetsWidth: CGFloat = 0.0

        if let insets = padding {
            insetsWidth += insets.left + insets.right
            insetsHeight += insets.top + insets.bottom
            textWidth -= insetsWidth
        }

        let newSize = text.boundingRect(with: CGSize(width: textWidth, height: CGFloat.greatestFiniteMagnitude),
                                        options: NSStringDrawingOptions.usesLineFragmentOrigin,
                                        attributes: [NSAttributedString.Key.font: self.font], context: nil)

        contentSize.height = ceil(newSize.size.height) + insetsHeight
        contentSize.width = ceil(newSize.size.width) + insetsWidth

        return contentSize
    }
}

没有故事板:

class PaddingLabel: UILabel {

    var topInset: CGFloat
    var bottomInset: CGFloat
    var leftInset: CGFloat
    var rightInset: CGFloat

    required init(withInsets top: CGFloat, _ bottom: CGFloat,_ left: CGFloat,_ right: CGFloat) {
        self.topInset = top
        self.bottomInset = bottom
        self.leftInset = left
        self.rightInset = right
        super.init(frame: CGRect.zero)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize {
        get {
            var contentSize = super.intrinsicContentSize
            contentSize.height += topInset + bottomInset
            contentSize.width += leftInset + rightInset
            return contentSize
        }
    }
}

用法:

let label = PaddingLabel(8, 8, 16, 16)
label.font = .boldSystemFont(ofSize: 16)
label.text = "Hello World"
label.backgroundColor = .black
label.textColor = .white
label.textAlignment = .center
label.layer.cornerRadius = 8
label.clipsToBounds = true
label.sizeToFit()

view.addSubview(label)

结果:

就像其他答案一样，但它修复了一个bug:

当标签。宽度由自动布局控制，有时文本会被裁剪。

@IBDesignable
class InsetLabel: UILabel {

    @IBInspectable var topInset: CGFloat = 4.0
    @IBInspectable var leftInset: CGFloat = 4.0
    @IBInspectable var bottomInset: CGFloat = 4.0
    @IBInspectable var rightInset: CGFloat = 4.0

    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsets.init(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }

    override func sizeThatFits(_ size: CGSize) -> CGSize {
        var adjSize = super.sizeThatFits(size)
        adjSize.width += leftInset + rightInset
        adjSize.height += topInset + bottomInset
        return adjSize
    }

    override var intrinsicContentSize: CGSize {
        let systemContentSize = super.intrinsicContentSize
        let adjustSize = CGSize(width: systemContentSize.width + leftInset + rightInset, height: systemContentSize.height + topInset +     bottomInset)
        if adjustSize.width > preferredMaxLayoutWidth && preferredMaxLayoutWidth != 0 {
            let constraintSize = CGSize(width: bounds.width - (leftInset + rightInset), height: .greatestFiniteMagnitude)
            let newSize = super.sizeThatFits(constraintSize)
            return CGSize(width: systemContentSize.width, height: ceil(newSize.height) + topInset + bottomInset)
        } else {
            return adjustSize
        }
    }

    override func drawText(in rect: CGRect) {
        super.drawText(in: rect.inset(by: insets))
    }
}