Xcode 6.1.1 Swift扩展解决方案。

文件名可以是"UILabel+AddInsetMargin.swift":

import UIKit

extension UILabel
{
    public override func drawRect(rect: CGRect)
    {
        self.drawTextInRect(UIEdgeInsetsInsetRect(rect, UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)))
    }
}

很多答案都缺少对sizeThatFits的重写。有了这个子类，你可以创建标签，设置填充，然后输入label。sizetofit()，瞧。

import UIKit

class UILabelEx : UILabel
{
    var padding : UIEdgeInsets = UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)

    override func drawTextInRect(rect: CGRect) {

        super.drawTextInRect(UIEdgeInsetsInsetRect(rect, padding))
    }

    override func sizeThatFits(size: CGSize) -> CGSize
    {

        var adjSize = super.sizeThatFits(size)
        adjSize.width += padding.left + padding.right
        adjSize.height += padding.top + padding.bottom

        return adjSize
    }
}

Swift 3 &自动布局兼容版本:

class InsetLabel: UILabel {

    var insets = UIEdgeInsets()

    convenience init(insets: UIEdgeInsets) {
        self.init(frame: CGRect.zero)
        self.insets = insets
    }

    convenience init(dx: CGFloat, dy: CGFloat) {
        let insets = UIEdgeInsets(top: dy, left: dx, bottom: dy, right: dx)
        self.init(insets: insets)
    }

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

    override var intrinsicContentSize: CGSize  {
        var size = super.intrinsicContentSize
        size.width += insets.left + insets.right
        size.height += insets.top + insets.bottom
        return size
    }
}

编辑:这个真的很老了。上面有更好的解决方案。

我最终只是在文本中添加了一些空格:

self.titleLabel.text = [NSString stringWithFormat:@"    %@", self.titleLabel.text];

丑陋但有效，不需要子类化。

你也可以试试“\t”。对于一般的解决方案，请参考已接受的答案

这适用于多行标签:

class PaddedLabel: UILabel {
    var verticalPadding: CGFloat = 0
    var horizontalPadding: CGFloat = 0

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

    override var intrinsicContentSize: CGSize {
        get {
            let textWidth = super.intrinsicContentSize.width - horizontalPadding * 2
            let textHeight = sizeThatFits(CGSize(width: textWidth, height: .greatestFiniteMagnitude)).height
            let width = textWidth + horizontalPadding * 2
            let height = textHeight + verticalPadding * 2
            return CGSize(width: frame.width, height: height)
        }
    }
}

这是我找到的最简单的解决方法:

斯威夫特4

class CustomLabel: UILabel{
    override func drawText(in rect: CGRect) {
        super.drawText(in: rect.inset(by: UIEdgeInsets.init(top: 10, left: 10, bottom: 10, right: 10)))
    }
}

确保在代码和故事板中都将标签设置为CustomLabel类。