Swift 3代码及其实现示例

class UIMarginLabel: UILabel {

    var topInset:       CGFloat = 0
    var rightInset:     CGFloat = 0
    var bottomInset:    CGFloat = 0
    var leftInset:      CGFloat = 0

    override func drawText(in rect: CGRect) {
        let insets: UIEdgeInsets = UIEdgeInsets(top: self.topInset, left: self.leftInset, bottom: self.bottomInset, right: self.rightInset)
        self.setNeedsLayout()
        return super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }
}

class LabelVC: UIViewController {

    //Outlets
    @IBOutlet weak var labelWithMargin: UIMarginLabel!

    override func viewDidLoad() {
        super.viewDidLoad()

        //Label settings.
        labelWithMargin.leftInset = 10
        view.layoutIfNeeded()
    }
}

不要忘记在故事板标签对象中添加类名UIMarginLabel。 编码快乐!

如果在应用填充时遇到文本修剪问题，请使用此代码。

@IBDesignable class PaddingLabel: UILabel {

    @IBInspectable var topInset: CGFloat = 5.0
    @IBInspectable var bottomInset: CGFloat = 5.0
    @IBInspectable var leftInset: CGFloat = 5.0
    @IBInspectable var rightInset: CGFloat = 5.0

    override func drawText(in rect: CGRect) {
        let insets = UIEdgeInsets.init(top: topInset, left: leftInset, bottom: bottomInset, right: rightInset)
        super.drawText(in: UIEdgeInsetsInsetRect(rect, insets))
    }

    override var intrinsicContentSize: CGSize {
        var intrinsicSuperViewContentSize = super.intrinsicContentSize
        let textWidth = frame.size.width - (self.leftInset + self.rightInset)
        let newSize = self.text!.boundingRect(with: CGSize(textWidth, CGFloat.greatestFiniteMagnitude), options: NSStringDrawingOptions.usesLineFragmentOrigin, attributes: [NSFontAttributeName: self.font], context: nil)
        intrinsicSuperViewContentSize.height = ceil(newSize.size.height) + self.topInset + self.bottomInset
        return intrinsicSuperViewContentSize
    }
}

extension CGSize{
    init(_ width:CGFloat,_ height:CGFloat) {
        self.init(width:width,height:height)
    }
}

Swift 3、iOS10解决方案:

open class UIInsetLabel: UILabel {

    open var insets : UIEdgeInsets = UIEdgeInsets() {
        didSet {
            super.invalidateIntrinsicContentSize()
        }
    }

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

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

简单的方法

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        // Do any additional setup after loading the view, typically from a nib.

        self.view.addSubview(makeLabel("my title",x: 0, y: 100, w: 320, h: 30))
    }

    func makeLabel(title:String, x:CGFloat, y:CGFloat, w:CGFloat, h:CGFloat)->UILabel{
        var myLabel : UILabel = UILabel(frame: CGRectMake(x,y,w,h))
        myLabel.textAlignment = NSTextAlignment.Right

        // inser last char to right
        var titlePlus1char = "\(title)1"
        myLabel.text = titlePlus1char
        var titleSize:Int = count(titlePlus1char)-1

        myLabel.textColor = UIColor(red:1.0, green:1.0,blue:1.0,alpha:1.0)
        myLabel.backgroundColor = UIColor(red: 214/255, green: 167/255, blue: 0/255,alpha:1.0)


        // create myMutable String
        var myMutableString = NSMutableAttributedString()

        // create myMutable font
        myMutableString = NSMutableAttributedString(string: titlePlus1char, attributes: [NSFontAttributeName:UIFont(name: "HelveticaNeue", size: 20)!])

        // set margin size
        myMutableString.addAttribute(NSFontAttributeName, value: UIFont(name: "HelveticaNeue", size: 10)!, range: NSRange(location: titleSize,length: 1))

        // set last char to alpha 0
        myMutableString.addAttribute(NSForegroundColorAttributeName, value: UIColor(red:1.0, green:1.0,blue:1.0,alpha:0), range: NSRange(location: titleSize,length: 1))

        myLabel.attributedText = myMutableString

        return myLabel
    }


    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

斯威夫特 4+

class EdgeInsetLabel: UILabel {
    var textInsets = UIEdgeInsets.zero {
        didSet { invalidateIntrinsicContentSize() }
    }

    override func textRect(forBounds bounds: CGRect, limitedToNumberOfLines numberOfLines: Int) -> CGRect {
        let textRect = super.textRect(forBounds: bounds, limitedToNumberOfLines: numberOfLines)
        let invertedInsets = UIEdgeInsets(top: -textInsets.top,
                                          left: -textInsets.left,
                                          bottom: -textInsets.bottom,
                                          right: -textInsets.right)
        return textRect.inset(by: invertedInsets)
    }

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

用法:

let label = EdgeInsetLabel()
label.textInsets = UIEdgeInsets(top: 2, left: 6, bottom: 2, right: 6)

另一个没有子类化的选项是:

设置标签文本 sizeToFit () 然后稍微增加标签高度以模拟填充 标签。text = "someText" 标签。textAlignment = .center label.sizeToFit () label.frame = CGRect(x: label.frame.x, y: label.frame.y,width: label.frame.width + 20,height: label.frame.height + 8)