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)
    }
}

为了消除单行标签的垂直填充，我做了:

// I have a category method setFrameHeight; you'll likely need to modify the frame.
[label setFrameHeight:font.pointSize];

或者，不带类别，使用:

CGRect frame = label.frame;
frame.size.height = font.pointSize;
label.frame = frame;

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])

为UILabel添加填充的最佳方法是子类化UILabel并添加一个edgeInsets属性。然后设置所需的插图，标签将相应地绘制。

OSLabel.h

#import <UIKit/UIKit.h>

@interface OSLabel : UILabel

@property (nonatomic, assign) UIEdgeInsets edgeInsets;

@end

OSLabel.m

#import "OSLabel.h"

@implementation OSLabel

- (id)initWithFrame:(CGRect)frame{
    self = [super initWithFrame:frame];
    if (self) {
        self.edgeInsets = UIEdgeInsetsMake(0, 0, 0, 0);
    }
    return self;
}

- (void)drawTextInRect:(CGRect)rect {
    [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

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:)

我认为UILabel类没有设置边距的方法。为什么不把标签的位置设置在需要的位置?

见下面的代码:

UILabel *label = [[UILabel alloc] init];
label.text = @"This is label";
label.frame = CGRectMake(0,0,100,100);

如果来自接口构建器，则按以下方式定位Label:

yourLabel.frame = CGRectMake(0,0,100,100);