在Swift 3中，你可以通过创建UILabel的子类来达到你想要的效果。在这个子类中，你必须添加一个UIEdgeInsets属性，并覆盖drawText(In:)方法，intrinsicContentSize属性(用于自动布局代码)和/或sizeThatFits(_:)方法(用于Springs和Struts代码)。

import UIKit

class PaddingLabel: UILabel {

    let padding: UIEdgeInsets

    // Create a new PaddingLabel instance programamtically with the desired insets
    required init(padding: UIEdgeInsets = UIEdgeInsets(top: 0, left: 10, bottom: 0, right: 10)) {
        self.padding = padding
        super.init(frame: CGRect.zero)
    }

    // Create a new PaddingLabel instance programamtically with default insets
    override init(frame: CGRect) {
        padding = UIEdgeInsets.zero // set desired insets value according to your needs
        super.init(frame: frame)
    }

    // Create a new PaddingLabel instance from Storyboard with default insets
    required init?(coder aDecoder: NSCoder) {
        padding = UIEdgeInsets.zero // set desired insets value according to your needs
        super.init(coder: aDecoder)
    }

    override func drawText(in rect: CGRect) {
        super.drawText(in: UIEdgeInsetsInsetRect(rect, padding))
    }

    // Override `intrinsicContentSize` property for Auto layout code
    override var intrinsicContentSize: CGSize {
        let superContentSize = super.intrinsicContentSize
        let width = superContentSize.width + padding.left + padding.right
        let height = superContentSize.height + padding.top + padding.bottom
        return CGSize(width: width, height: height)
    }

    // Override `sizeThatFits(_:)` method for Springs & Struts code
    override func sizeThatFits(_ size: CGSize) -> CGSize {
        let superSizeThatFits = super.sizeThatFits(size)
        let width = superSizeThatFits.width + padding.left + padding.right
        let heigth = superSizeThatFits.height + padding.top + padding.bottom
        return CGSize(width: width, height: heigth)
    }

}

下面的例子展示了如何在UIViewController中使用PaddingLabel实例:

import UIKit

class ViewController: UIViewController {

    @IBOutlet weak var storyboardAutoLayoutLabel: PaddingLabel!
    let autoLayoutLabel = PaddingLabel(padding: UIEdgeInsets(top: 20, left: 40, bottom: 20, right: 40))
    let springsAndStructsLabel = PaddingLabel(frame: CGRect.zero)
    var textToDisplay = "Lorem ipsum dolor sit er elit lamet."

    override func viewDidLoad() {
        super.viewDidLoad()

        // Set autoLayoutLabel
        autoLayoutLabel.text = textToDisplay
        autoLayoutLabel.backgroundColor = .red
        autoLayoutLabel.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(autoLayoutLabel)
        autoLayoutLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 30).isActive = true
        autoLayoutLabel.centerYAnchor.constraint(equalTo: view.centerYAnchor).isActive = true

        // Set springsAndStructsLabel
        springsAndStructsLabel.text = textToDisplay
        springsAndStructsLabel.backgroundColor = .green
        view.addSubview(springsAndStructsLabel)
        springsAndStructsLabel.frame.origin = CGPoint(x: 30, y: 90)
        springsAndStructsLabel.sizeToFit()

        // Set storyboardAutoLayoutLabel
        storyboardAutoLayoutLabel.text = textToDisplay
        storyboardAutoLayoutLabel.backgroundColor = .blue
    }

    // Link this IBAction to a UIButton or a UIBarButtonItem in Storyboard
    @IBAction func updateLabelText(_ sender: Any) {
        textToDisplay = textToDisplay == "Lorem ipsum dolor sit er elit lamet." ? "Lorem ipsum." : "Lorem ipsum dolor sit er elit lamet."

        // autoLayoutLabel
        autoLayoutLabel.text = textToDisplay

        // springsAndStructsLabel
        springsAndStructsLabel.text = textToDisplay
        springsAndStructsLabel.sizeToFit()

        // storyboardAutoLayoutLabel
        storyboardAutoLayoutLabel.text = textToDisplay
    }

}

blyabtroi的asnwer在Swift中转换(不需要子类化)

let style: NSMutableParagraphStyle = NSParagraphStyle.defaultParagraphStyle().mutableCopy() as! NSMutableParagraphStyle
style.alignment = .Justified
style.firstLineHeadIndent = 10.0
style.headIndent = 10.0
style.tailIndent = -10.0
let attrText: NSAttributedString = NSAttributedString(string: title, attributes: [NSParagraphStyleAttributeName:style])
let label: UILabel = UILabel(frame: someFrame)
label.numberOfLines = 0
label.attributedText = attrText

我通过子类化UILabel和重写drawTextInRect来解决这个问题:

- (void)drawTextInRect:(CGRect)rect {
    UIEdgeInsets insets = {0, 5, 0, 5};
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, insets)];
}

斯威夫特3.1:

override func drawText(in rect: CGRect) {
    let insets = UIEdgeInsets.init(top: 0, left: 5, bottom: 0, right: 5)
    super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}

斯威夫特4.2.1:准备

override func drawText(in rect: CGRect) {
    let insets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
    super.drawText(in: rect.inset(by: insets))
}

你可能已经猜到了，这是对tc的改编。的答案。它有两个优点:

没有必要通过发送sizeToFit消息来触发它 它只保留标签框架——如果你的标签有背景，而你不想让它缩小，这很方便

也许你可以试试这段代码

CGRect frame = btn.titleLabel.frame;
int indent = 20;
int inset = 20;
[btn.titleLabel setFrame:CGRectMake(frame.origin.x+inset,frame.origin.y,frame.size.width+indent,frame.size.height)];

回收钢铁的答案的Swift版本+ intrinsizeContentSize()。

它支持一个更传统的设置insets为其他视图对象的insets，同时能够设置insets在接口生成器，即insets设置像这样编程:

label.insets = UIEdgeInsetsMake(0, 0, 5, 0)

如果有任何错误，请告诉我。

斯威夫特5

@IBInspectable var topInset: CGFloat = 0.0
@IBInspectable var leftInset: CGFloat = 0.0
@IBInspectable var bottomInset: CGFloat = 0.0
@IBInspectable var rightInset: CGFloat = 0.0

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

override func drawText(in rect: CGRect) {
    super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
}

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

斯威夫特4.2

@IBDesignable class InsetLabel: UILabel {
    @IBInspectable var topInset: CGFloat = 0.0
    @IBInspectable var leftInset: CGFloat = 0.0
    @IBInspectable var bottomInset: CGFloat = 0.0
    @IBInspectable var rightInset: CGFloat = 0.0
    
    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsetsMake(topInset, leftInset, bottomInset, rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }
    
    override func drawText(in rect: CGRect) {
        super.drawText(in: rect.inset(by: insets))
    }
    
    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 {
        var contentSize = super.intrinsicContentSize
        contentSize.width += leftInset + rightInset
        contentSize.height += topInset + bottomInset
        
        return contentSize
    }
}

斯威夫特3

@IBDesignable class InsetLabel: UILabel {
    @IBInspectable var topInset: CGFloat = 0.0
    @IBInspectable var leftInset: CGFloat = 0.0
    @IBInspectable var bottomInset: CGFloat = 0.0
    @IBInspectable var rightInset: CGFloat = 0.0
    
    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsetsMake(topInset, leftInset, bottomInset, rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }
    
    override func drawText(in rect: CGRect) {
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }
    
    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 {
        var contentSize = super.intrinsicContentSize
        contentSize.width += leftInset + rightInset
        contentSize.height += topInset + bottomInset
        
        return contentSize
    }
}

斯威夫特2.2

@IBDesignable class InsetLabel: UILabel {
    @IBInspectable var topInset: CGFloat = 0.0
    @IBInspectable var leftInset: CGFloat = 0.0
    @IBInspectable var bottomInset: CGFloat = 0.0
    @IBInspectable var rightInset: CGFloat = 0.0
    
    var insets: UIEdgeInsets {
        get {
            return UIEdgeInsetsMake(topInset, leftInset, bottomInset, rightInset)
        }
        set {
            topInset = newValue.top
            leftInset = newValue.left
            bottomInset = newValue.bottom
            rightInset = newValue.right
        }
    }
        
    override func drawTextInRect(rect: CGRect) {
        super.drawTextInRect(UIEdgeInsetsInsetRect(rect, insets))
    }
        
    override func sizeThatFits(size: CGSize) -> CGSize {
        var adjSize = super.sizeThatFits(size)
        adjSize.width += leftInset + rightInset
        adjSize.height += topInset + bottomInset
        
        return adjSize
    }
    
    override func intrinsicContentSize() -> CGSize {
        var contentSize = super.intrinsicContentSize()
        contentSize.width += leftInset + rightInset
        contentSize.height += topInset + bottomInset
        
        return contentSize
    }
}

我已经用xcode构建器解决了它(但肯定这可以通过swift使用约束来实现):

只需要创建一个相应大小的UIView 并添加一个UILabel类型的子视图

好了，你有填充了:)