Swift 4版的blyabtroi解决方案

let leadingMargin: CGFloat = 10
let trailingMargin: CGFloat = 10

let style = NSMutableParagraphStyle()
style.alignment = .justified
style.firstLineHeadIndent = leadingMargin
style.headIndent = leadingMargin
style.tailIndent = trailingMargin

label.attributedText = NSAttributedString(string: "Label with margins", 
                                          attributes: [NSAttributedStringKey.paragraphStyle: style])

如果是单行，只需在左侧添加空格，超过一行的填充将再次为0。

[self.myLabel setText:[NSString stringWithFormat:@"   %@", self.myShortString]];

你需要计算UILabel大小，当你放置嵌入。它可以有不同的行数，因为文本对齐，换行模式。

override func drawText(in rect: CGRect) {

    let size = self.sizeThatFits(UIEdgeInsetsInsetRect(rect, insets).size);
    super.drawText(in: CGRect.init(origin: CGPoint.init(x: insets.left, y: insets.top), size: size));
}

override var intrinsicContentSize: CGSize {

    var size = super.intrinsicContentSize;

    if text == nil || text?.count == 0 {
        return size;
    }

    size = self.sizeThatFits(UIEdgeInsetsInsetRect(CGRect.init(origin: CGPoint.zero, size: size), insets).size);
    size.width  += self.insets.left + self.insets.right;
    size.height += self.insets.top + self.insets.bottom;

    return size;
}

尝试 iEun/InsetLabel

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:)

对于多行文本，可以使用NSAttributedString设置左右边距。

NSMutableParagraphStyle *style =  [[NSParagraphStyle defaultParagraphStyle] mutableCopy];
style.alignment = NSTextAlignmentJustified;
style.firstLineHeadIndent = 10.0f;
style.headIndent = 10.0f;
style.tailIndent = -10.0f;   

NSAttributedString *attrText = [[NSAttributedString alloc] initWithString:title attributes:@{ NSParagraphStyleAttributeName : style}];  

UILabel * label = [[UILabel alloc] initWithFrame:someFrame];
label.numberOfLines = 0;
label.attributedText = attrText;

以下是Swift 5采用的上述示例:

extension UILabel {
    func setMargins(margin: CGFloat = 10) {
        if let textString = self.text {
            var paragraphStyle = NSMutableParagraphStyle()
            paragraphStyle.firstLineHeadIndent = margin
            paragraphStyle.headIndent = margin
            paragraphStyle.tailIndent = -margin
            let attributedString = NSMutableAttributedString(string: textString)
            attributedString.addAttribute(.paragraphStyle, value: paragraphStyle, range: NSRange(location: 0, length: attributedString.length))
            attributedText = attributedString
        }
    }
}

你也可以用一个自定义框架初始化你的UILabel来解决这个问题。

    CGRect initialFrame = CGRectMake(0, 0, 100, 100);
    UIEdgeInsets contentInsets = UIEdgeInsetsMake(0, 10, 0, 0);
    CGRect paddedFrame = UIEdgeInsetsInsetRect(initialFrame, contentInsets);

    self.label = [[UILabel alloc] initWithFrame:paddedFrame];

向CGRect Tricks致敬。