如果你不想使用一个额外的父视图来设置背景，你可以子类化UILabel并重写textRectForBounds: limitedtonumberolines:。我会添加一个textEdgeInsets属性或类似的，然后做

- (CGRect)textRectForBounds:(CGRect)bounds limitedToNumberOfLines:(NSInteger)numberOfLines
{
  return [super textRectForBounds:UIEdgeInsetsInsetRect(bounds,textEdgeInsets) limitedToNumberOfLines:numberOfLines];
}

为了健壮性，你可能还想在setTextEdgeInsets:中调用[self setNeedsDisplay]，但我通常不这么做。

也许过会儿再去派对，但下面的就行了。只是UILabel的子类。

#import "UITagLabel.h"

#define padding UIEdgeInsetsMake(5, 10, 5, 10)

@implementation UITagLabel

- (void)drawTextInRect:(CGRect)rect {
    [super drawTextInRect:UIEdgeInsetsInsetRect(rect, padding)];
}

- (CGSize) intrinsicContentSize {
    CGSize superContentSize = [super intrinsicContentSize];
    CGFloat width = superContentSize.width + padding.left + padding.right;
    CGFloat height = superContentSize.height + padding.top + padding.bottom;
    return CGSizeMake(width, height);
}

- (CGSize) sizeThatFits:(CGSize)size {
    CGSize superSizeThatFits = [super sizeThatFits:size];
    CGFloat width = superSizeThatFits.width + padding.left + padding.right;
    CGFloat height = superSizeThatFits.height + padding.top + padding.bottom;
    return CGSizeMake(width, height);
}

@end

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)];

这是我发现的最简单的方法。这对我来说很有魔力。

UIView *titleSection = [[UIView alloc] initWithFrame:CGRectMake(0, 0, screenWidth, 100)];
[titleSection addSubview:titleSection];

UILabel *label = [[UILabel alloc] initWithFrame:CGRectInset(titleSection.frame, PADDING, 0)];
[titleSection addSubview:label];

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:)

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
    }

}