这个类是基于所有的评论和建议的答案，也可以直接从xcode设计。复制到你的项目并插入任何UIButton并更改为使用自定义类，现在只需从xcode中选择正常和/或高亮显示状态的边框或背景颜色。

//
//  RoundedButton.swift
//

import UIKit

@IBDesignable
class RoundedButton:UIButton {

    @IBInspectable var borderWidth: CGFloat = 0 {
        didSet {
            layer.borderWidth = borderWidth
        }
    }
    //Normal state bg and border
    @IBInspectable var normalBorderColor: UIColor? {
        didSet {
            layer.borderColor = normalBorderColor?.CGColor
        }
    }

    @IBInspectable var normalBackgroundColor: UIColor? {
        didSet {
            setBgColorForState(normalBackgroundColor, forState: .Normal)
        }
    }


    //Highlighted state bg and border
    @IBInspectable var highlightedBorderColor: UIColor?

    @IBInspectable var highlightedBackgroundColor: UIColor? {
        didSet {
            setBgColorForState(highlightedBackgroundColor, forState: .Highlighted)
        }
    }


    private func setBgColorForState(color: UIColor?, forState: UIControlState){
        if color != nil {
            setBackgroundImage(UIImage.imageWithColor(color!), forState: forState)

        } else {
            setBackgroundImage(nil, forState: forState)
        }
    }

    override func layoutSubviews() {
        super.layoutSubviews()

        layer.cornerRadius = layer.frame.height / 2
        clipsToBounds = true

        if borderWidth > 0 {
            if state == .Normal && !CGColorEqualToColor(layer.borderColor, normalBorderColor?.CGColor) {
                layer.borderColor = normalBorderColor?.CGColor
            } else if state == .Highlighted && highlightedBorderColor != nil{
                layer.borderColor = highlightedBorderColor!.CGColor
            }
        }
    }

}

//Extension Required by RoundedButton to create UIImage from UIColor
extension UIImage {
    class func imageWithColor(color: UIColor) -> UIImage {
        let rect: CGRect = CGRectMake(0, 0, 1, 1)
        UIGraphicsBeginImageContextWithOptions(CGSizeMake(1, 1), false, 1.0)
        color.setFill()
        UIRectFill(rect)
        let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return image
    }
}

你可以使用UIButton的子类来根据你的需要定制UIButton。

访问这个github回购参考

class RoundedRectButton: UIButton {

    var selectedState: Bool = false

    override func awakeFromNib() {
        super.awakeFromNib()
        layer.borderWidth = 2 / UIScreen.main.nativeScale
        layer.borderColor = UIColor.white.cgColor
        contentEdgeInsets = UIEdgeInsets(top: 0, left: 5, bottom: 0, right: 5)
    }


    override func layoutSubviews(){
        super.layoutSubviews()
        layer.cornerRadius = frame.height / 2
        backgroundColor = selectedState ? UIColor.white : UIColor.clear
        self.titleLabel?.textColor = selectedState ? UIColor.green : UIColor.white
    }

    override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
        selectedState = !selectedState
        self.layoutSubviews()
    }
}

使用button.layer。cornerRadius, button.layer.borderColor和button.layer.borderWidth。 注意borderColor需要CGColor，所以你可以说(Swift 3/4):

button.backgroundColor = .clear
button.layer.cornerRadius = 5
button.layer.borderWidth = 1
button.layer.borderColor = UIColor.black.cgColor

@IBOutlet weak var yourButton: UIButton! {
    didSet{
        yourButton.backgroundColor = .clear
        yourButton.layer.cornerRadius = 10
        yourButton.layer.borderWidth = 2
        yourButton.layer.borderColor = UIColor.white.cgColor
    }
}

我已经创建了一个简单的UIButton子模块，它使用tintColor作为文本和边框颜色，当高亮显示时，它的背景改变为tintColor。

class BorderedButton: UIButton {

required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    layer.borderWidth = 1.0
    layer.borderColor = tintColor.CGColor
    layer.cornerRadius = 5.0
    clipsToBounds = true
    contentEdgeInsets = UIEdgeInsets(top: 8, left: 8, bottom: 8, right: 8)
    setTitleColor(tintColor, forState: .Normal)
    setTitleColor(UIColor.whiteColor(), forState: .Highlighted)
    setBackgroundImage(UIImage(color: tintColor), forState: .Highlighted)
}
}

这利用了一个UIImage扩展，从一个颜色创建一个图像，我发现代码在这里:https://stackoverflow.com/a/33675160

当在界面构建器中设置为自定义类型时，它工作得最好，因为默认的系统类型会在按钮突出显示时略微修改颜色。

import UIKit

@IBDesignable
class RoundedButton: UIButton {
    
    @IBInspectable var cornerRadius: CGFloat = 8
    @IBInspectable var borderColor: UIColor? = .lightGray
    
    override func draw(_ rect: CGRect) {
        layer.cornerRadius = cornerRadius
        layer.masksToBounds = true
        layer.borderWidth = 1
        layer.borderColor = borderColor?.cgColor
        
    }
    
    
}