和@IBDesignable，使其与接口生成器一起工作

斯威夫特4

//
//  PaddedLabel.swift
//  TrainCentric
//
//  Created by Arsonik
//  https://stackoverflow.com/a/33244365/337934
//

import UIKit

@IBDesignable
class PaddedLabel: UILabel {

    @IBInspectable var inset:CGSize = CGSize(width: 0, height: 0)

    var padding: UIEdgeInsets {
        var hasText:Bool = false
        if let t = self.text?.count, t > 0 {
            hasText = true
        }
        else if let t = attributedText?.length, t > 0 {
            hasText = true
        }

        return hasText ? UIEdgeInsets(top: inset.height, left: inset.width, bottom: inset.height, right: inset.width) : UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
    }

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

    override var intrinsicContentSize: CGSize {
        let superContentSize = super.intrinsicContentSize
        let p = padding
        let width = superContentSize.width + p.left + p.right
        let heigth = superContentSize.height + p.top + p.bottom
        return CGSize(width: width, height: heigth)
    }

    override func sizeThatFits(_ size: CGSize) -> CGSize {
        let superSizeThatFits = super.sizeThatFits(size)
        let p = padding
        let width = superSizeThatFits.width + p.left + p.right
        let heigth = superSizeThatFits.height + p.top + p.bottom
        return CGSize(width: width, height: heigth)
    }
}

斯威夫特2

@IBDesignable
class PaddedLabel: UILabel {

    @IBInspectable var inset:CGSize = CGSize(width: 0, height: 0)

    var padding: UIEdgeInsets {
        var hasText:Bool = false
        if let t = text?.length where t > 0 {
            hasText = true
        }
        else if let t = attributedText?.length where t > 0 {
            hasText = true
        }

        return hasText ? UIEdgeInsets(top: inset.height, left: inset.width, bottom: inset.height, right: inset.width) : UIEdgeInsets(top: 0, left: 0, bottom: 0, right: 0)
    }

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

    override func intrinsicContentSize() -> CGSize {
        let superContentSize = super.intrinsicContentSize()
        let p = padding
        let width = superContentSize.width + p.left + p.right
        let heigth = superContentSize.height + p.top + p.bottom
        return CGSize(width: width, height: heigth)
    }

    override func sizeThatFits(size: CGSize) -> CGSize {
        let superSizeThatFits = super.sizeThatFits(size)
        let p = padding
        let width = superSizeThatFits.width + p.left + p.right
        let heigth = superSizeThatFits.height + p.top + p.bottom
        return CGSize(width: width, height: heigth)
    }
}

在Swift中，它是这样解决的。

class Label: UILabel {
    override func drawTextInRect(rect: CGRect) {
        super.drawTextInRect(UIEdgeInsetsInsetRect(rect, UIEdgeInsets(top: 0, left: 10, bottom: 0, right: 10)))
    }
}

对于这样一个简单的情况，子类化有点麻烦。另一种方法是将没有背景设置的UILabel添加到有背景设置的UIView中。将标签的x设置为10，并使外部视图的大小比标签宽20个像素。

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:)

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])

要扩展Brody Robertson提供的答案，您可以添加IB可设计位。这意味着您可以在Storyboard中调整标签。

在你的子类UILabel做

#import <UIKit/UIKit.h>

IB_DESIGNABLE

@interface insetLabel : UILabel

@property (nonatomic, assign) IBInspectable CGFloat leftEdge;
@property (nonatomic, assign) IBInspectable CGFloat rightEdge;
@property (nonatomic, assign) IBInspectable CGFloat topEdge;
@property (nonatomic, assign) IBInspectable CGFloat bottomEdge;

@property (nonatomic, assign) UIEdgeInsets edgeInsets;

@end

然后做;

#import "insetLabel.h"

@implementation insetLabel

- (id)initWithFrame:(CGRect)frame
{
    self = [super initWithFrame:frame];
    if (self)
    {
        self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);
    }
    return self;
}

- (void)drawTextInRect:(CGRect)rect
{
    self.edgeInsets = UIEdgeInsetsMake(self.topEdge, self.leftEdge, self.bottomEdge, self.rightEdge);

    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, self.edgeInsets)];
}

- (CGSize)intrinsicContentSize
{
    CGSize size = [super intrinsicContentSize];
    size.width  += self.edgeInsets.left + self.edgeInsets.right;
    size.height += self.edgeInsets.top + self.edgeInsets.bottom;
    return size;
}

@end

EDIT

你应该为edgeInsets添加一个setter方法。