ios Swift - 圆角半径和阴影问题

Swift - Problems with corner radius and drop shadow

提问by Jake

I'm trying to create a button with rounded cornersand a drop shadow. No matter how I switch up, the button will not display correctly. I've tried masksToBounds = falseand masksToBounds = true, but either the corner radius works and the shadow does not or the shadow works and the corner radius doesn't clip the corners of the button.

我正在尝试创建一个带有圆角和阴影的按钮。无论我如何切换，该按钮都无法正确显示。我试过masksToBounds = falseand masksToBounds = true，但要么角半径有效而阴影不起作用，要么阴影有效且角半径不夹住按钮的角。

import UIKit
import QuartzCore

@IBDesignable
class Button : UIButton
{
    @IBInspectable var masksToBounds: Bool    = false                {didSet{updateLayerProperties()}}
    @IBInspectable var cornerRadius : CGFloat = 0                    {didSet{updateLayerProperties()}}
    @IBInspectable var borderWidth  : CGFloat = 0                    {didSet{updateLayerProperties()}}
    @IBInspectable var borderColor  : UIColor = UIColor.clearColor() {didSet{updateLayerProperties()}}
    @IBInspectable var shadowColor  : UIColor = UIColor.clearColor() {didSet{updateLayerProperties()}}
    @IBInspectable var shadowOpacity: CGFloat = 0                    {didSet{updateLayerProperties()}}
    @IBInspectable var shadowRadius : CGFloat = 0                    {didSet{updateLayerProperties()}}
    @IBInspectable var shadowOffset : CGSize  = CGSizeMake(0, 0)     {didSet{updateLayerProperties()}}

    override func drawRect(rect: CGRect)
    {
        updateLayerProperties()
    }

    func updateLayerProperties()
    {
        self.layer.masksToBounds = masksToBounds
        self.layer.cornerRadius = cornerRadius
        self.layer.borderWidth = borderWidth
        self.layer.borderColor = borderColor.CGColor
        self.layer.shadowColor = shadowColor.CGColor
        self.layer.shadowOpacity = CFloat(shadowOpacity)
        self.layer.shadowRadius = shadowRadius
        self.layer.shadowOffset = shadowOffset
    }
}

回答by Imanou Petit

The following Swift 5 / iOS 12 code shows how to set a subclass of UIButtonthat allows to create instances with rounded corners and shadow around it:

以下 Swift 5 / iOS 12 代码展示了如何设置UIButton允许创建带有圆角和阴影的实例的子类：

import UIKit

final class CustomButton: UIButton {

    private var shadowLayer: CAShapeLayer!

    override func layoutSubviews() {
        super.layoutSubviews()

        if shadowLayer == nil {
            shadowLayer = CAShapeLayer()
            shadowLayer.path = UIBezierPath(roundedRect: bounds, cornerRadius: 12).cgPath
            shadowLayer.fillColor = UIColor.white.cgColor

            shadowLayer.shadowColor = UIColor.darkGray.cgColor
            shadowLayer.shadowPath = shadowLayer.path
            shadowLayer.shadowOffset = CGSize(width: 2.0, height: 2.0)
            shadowLayer.shadowOpacity = 0.8
            shadowLayer.shadowRadius = 2

            layer.insertSublayer(shadowLayer, at: 0)
            //layer.insertSublayer(shadowLayer, below: nil) // also works
        }        
    }

}

According to your needs, you may add a UIButtonin your Storyboard and set its class to CustomButtonor you may create an instance of CustomButtonprogrammatically. The following UIViewControllerimplementation shows how to create and use a CustomButtoninstance programmatically:

根据您的需要，您可以UIButton在 Storyboard 中添加 a并将其类设置为CustomButton或者您可以以CustomButton编程方式创建一个实例。以下UIViewController实现显示了如何以CustomButton编程方式创建和使用实例：

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        let button = CustomButton(type: .system)
        button.setTitle("Button", for: .normal)
        view.addSubview(button)

        button.translatesAutoresizingMaskIntoConstraints = false
        let horizontalConstraint = button.centerXAnchor.constraint(equalTo: view.centerXAnchor)
        let verticalConstraint = button.centerYAnchor.constraint(equalTo: view.centerYAnchor)        
        let widthConstraint = button.widthAnchor.constraint(equalToConstant: 100)
        let heightConstraint = button.heightAnchor.constraint(equalToConstant: 100)
        NSLayoutConstraint.activate([horizontalConstraint, verticalConstraint, widthConstraint, heightConstraint])
    }

}

---

---

The previous code produces the image below in the iPhone simulator:

前面的代码在 iPhone 模拟器中生成下面的图像：

回答by scope

My custom buttonwith some shadowand rounded corners, I use it directly within the Storyboardwith no need to touchit programmatically.

我的自定义按钮带有一些阴影和圆角，我直接在其中使用它Storyboard，无需以编程方式触摸它。

Swift 4

斯威夫特 4

class RoundedButtonWithShadow: UIButton {
    override func awakeFromNib() {
        super.awakeFromNib()
        self.layer.masksToBounds = false
        self.layer.cornerRadius = self.frame.height/2
        self.layer.shadowColor = UIColor.black.cgColor
        self.layer.shadowPath = UIBezierPath(roundedRect: self.bounds, cornerRadius: self.layer.cornerRadius).cgPath
        self.layer.shadowOffset = CGSize(width: 0.0, height: 3.0)
        self.layer.shadowOpacity = 0.5
        self.layer.shadowRadius = 1.0
    }
}

回答by Matt Pinkston

To expand on Imanou's post, it's possible to programmatically add the shadow layer in the custom button class

为了扩展 Imanou 的帖子，可以在自定义按钮类中以编程方式添加阴影层

@IBDesignable class CustomButton: UIButton {
    var shadowAdded: Bool = false

    @IBInspectable var cornerRadius: CGFloat = 0 {
        didSet {
            layer.cornerRadius = cornerRadius
            layer.masksToBounds = cornerRadius > 0
        }
    }

    override func drawRect(rect: CGRect) {
        super.drawRect(rect)

        if shadowAdded { return }
        shadowAdded = true

        let shadowLayer = UIView(frame: self.frame)
        shadowLayer.backgroundColor = UIColor.clearColor()
        shadowLayer.layer.shadowColor = UIColor.darkGrayColor().CGColor
        shadowLayer.layer.shadowPath = UIBezierPath(roundedRect: bounds, cornerRadius: self.cornerRadius).CGPath
        shadowLayer.layer.shadowOffset = CGSize(width: 1.0, height: 1.0)
        shadowLayer.layer.shadowOpacity = 0.5
        shadowLayer.layer.shadowRadius = 1
        shadowLayer.layer.masksToBounds = true
        shadowLayer.clipsToBounds = false

        self.superview?.addSubview(shadowLayer)
        self.superview?.bringSubviewToFront(self)
    }
}

回答by aytek

An alternative way to get more usable and consistent button.

获得更多可用和一致按钮的另一种方法。

Swift 2:

斯威夫特 2：

func getImageWithColor(color: UIColor, size: CGSize, cornerRadius:CGFloat) -> UIImage {
    let rect = CGRectMake(0, 0, size.width, size.height)
    UIGraphicsBeginImageContextWithOptions(size, false, 1)
    UIBezierPath(
        roundedRect: rect,
        cornerRadius: cornerRadius
        ).addClip()
    color.setFill()
    UIRectFill(rect)
    let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    return image
}

let button = UIButton(type: .Custom)
button.frame = CGRectMake(20, 20, 200, 50)
button.setTitle("My Button", forState: UIControlState.Normal)
button.setTitleColor(UIColor.blackColor(), forState: UIControlState.Normal)
self.addSubview(button)

let image = getImageWithColor(UIColor.whiteColor(), size: button.frame.size, cornerRadius: 5)
button.setBackgroundImage(image, forState: UIControlState.Normal)

button.layer.shadowRadius = 5
button.layer.shadowColor = UIColor.blackColor().CGColor
button.layer.shadowOpacity = 0.5
button.layer.shadowOffset = CGSizeMake(0, 1)
button.layer.masksToBounds = false

Swift 3:

斯威夫特 3：

func getImageWithColor(_ color: UIColor, size: CGSize, cornerRadius:CGFloat) -> UIImage? {
    let rect = CGRect(x: 0, y: 0, width: size.width, height: size.height)
    UIGraphicsBeginImageContextWithOptions(size, false, 0)
    color.setFill()
    UIBezierPath(roundedRect: rect, cornerRadius: cornerRadius).addClip()
    color.setFill()
    UIRectFill(rect)
    let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
    UIGraphicsEndImageContext()
    return image
}

let button = UIButton(type: .custom)
button.frame = CGRect(x:20, y:20, width:200, height:50)
button.setTitle("My Button", for: .normal)
button.setTitleColor(UIColor.black, for: .normal)
self.addSubview(button)

if let image = getImageWithColor(UIColor.white, size: button.frame.size, cornerRadius: 5) {
    button.setBackgroundImage(image, for: .normal)
}

button.layer.shadowRadius = 5
button.layer.shadowColor = UIColor.black.cgColor
button.layer.shadowOpacity = 0.5
button.layer.shadowOffset = CGSize(width:0, height:1)
button.layer.masksToBounds = false

回答by hardanger

To improve PiterPan's answer and show a real shadow (not just a background with no blur) with a circular button in Swift 3:

要改进 PiterPan 的答案并在 Swift 3 中使用圆形按钮显示真实阴影（不仅仅是没有模糊的背景）：

override func viewDidLoad() {
    super.viewDidLoad()
    myButton.layer.masksToBounds = false
    myButton.layer.cornerRadius = myButton.frame.height/2
    myButton.clipsToBounds = true
}

override func viewDidLayoutSubviews() {
    addShadowForRoundedButton(view: self.view, button: myButton, opacity: 0.5)
}

func addShadowForRoundedButton(view: UIView, button: UIButton, opacity: Float = 1) {
    let shadowView = UIView()
    shadowView.backgroundColor = UIColor.black
    shadowView.layer.opacity = opacity
    shadowView.layer.shadowRadius = 5
    shadowView.layer.shadowOpacity = 0.35
    shadowView.layer.shadowOffset = CGSize(width: 0, height: 0)
    shadowView.layer.cornerRadius = button.bounds.size.width / 2
    shadowView.frame = CGRect(origin: CGPoint(x: button.frame.origin.x, y: button.frame.origin.y), size: CGSize(width: button.bounds.width, height: button.bounds.height))
    self.view.addSubview(shadowView)
    view.bringSubview(toFront: button)
}

回答by Jonny

Refactored thisto support any view. Subclass your view from this and it should have rounded corners. If you add something like a UIVisualEffectView as a subview to this view you likely need to use the same rounded corners on that UIVisualEffectView or it won't have rounded corners.

重构它以支持任何视图。从这个子类化你的视图，它应该有圆角。如果您将 UIVisualEffectView 之类的内容添加为该视图的子视图，您可能需要在该 UIVisualEffectView 上使用相同的圆角，否则它不会有圆角。

/// Inspiration: https://stackoverflow.com/a/25475536/129202
class ViewWithRoundedcornersAndShadow: UIView {
    private var theShadowLayer: CAShapeLayer?

    override func layoutSubviews() {
        super.layoutSubviews()

        if self.theShadowLayer == nil {
            let rounding = CGFloat.init(22.0)

            let shadowLayer = CAShapeLayer.init()
            self.theShadowLayer = shadowLayer
            shadowLayer.path = UIBezierPath.init(roundedRect: bounds, cornerRadius: rounding).cgPath
            shadowLayer.fillColor = UIColor.clear.cgColor

            shadowLayer.shadowPath = shadowLayer.path
            shadowLayer.shadowColor = UIColor.black.cgColor
            shadowLayer.shadowRadius = CGFloat.init(3.0)
            shadowLayer.shadowOpacity = Float.init(0.2)
            shadowLayer.shadowOffset = CGSize.init(width: 0.0, height: 4.0)

            self.layer.insertSublayer(shadowLayer, at: 0)
        }
    }
}

回答by Hari R Krishna

Swift 5 &No need of "UIBezierPath"

Swift 5 &不需要“UIBezierPath”

    view.layer.cornerRadius = 15
    view.clipsToBounds = true
    view.layer.masksToBounds = false
    view.layer.shadowRadius = 7
    view.layer.shadowOpacity = 0.6
    view.layer.shadowOffset = CGSize(width: 0, height: 5)
    view.layer.shadowColor = UIColor.red.cgColor

回答by Fattie

Exact solution for 2020 syntax

2020 语法的精确解决方案

import UIKit
class ColorAndShadowButton: UIButton {
    override init(frame: CGRect) { super.init(frame: frame), common() }
    required init?(coder aDecoder: NSCoder) { super.init(coder: aDecoder), common() }
    private func common() {
        // UIButton is tricky: you MUST set the clear bg in bringup;  NOT in layout
        backgroundColor = .clear
        clipsToBounds = false
        self.layer.insertSublayer(backgroundAndShadow, below: layer)
    }

   lazy var colorAndShadow: CAShapeLayer = {
        let s = CAShapeLayer()
        // set your button color HERE (NOT on storyboard)
        s.fillColor = UIColor.black.cgColor
        // now set your shadow color/values
        s.shadowColor = UIColor.red.cgColor
        s.shadowOffset = CGSize(width: 0, height: 10)
        s.shadowOpacity = 1
        s.shadowRadius = 10
        // now add the shadow
        layer.insertSublayer(s, at: 0)
        return s
    }()

    override func layoutSubviews() {
        super.layoutSubviews()
        // you MUST layout these two EVERY layout cycle:
        colorAndShadow = bounds
        colorAndShadow = UIBezierPath(roundedRect: bounds, cornerRadius: 12).cgPath
    }
}

• Note that the very old top answer here is correct but has a critical error

• 请注意，这里非常古老的最佳答案是正确的，但有一个严重错误

Note that UIButtonis unfortunately quite different from UIViewin iOS.

请注意，UIButton不幸的是，这UIView与 iOS 中的完全不同。

• Due to a strange behavior in iOS, you must set the background color (which of course must be clear in this case) in initialization, not in layout. You could just set it clear in storyboard (but you usually click it to be some solid color simply so you can see it when working in storyboard.)

• 由于 iOS 中的一个奇怪行为，您必须在初始化而不是在 layout 中设置背景颜色（在这种情况下当然必须清楚）。您可以在情节提要中将其设置为清晰（但您通常单击它以使其成为某种纯色，以便在情节提要中工作时可以看到它。）

In general combos of shadows/rounding are a real pain in iOS. Similar solutions:

一般来说，阴影/圆角的组合在 iOS 中是一个真正的痛点。类似的解决方案：

https://stackoverflow.com/a/57465440/294884- image + rounded + shadows
https://stackoverflow.com/a/41553784/294884- two-corner problem
https://stackoverflow.com/a/59092828/294884- "shadows + hole" or "glowbox" problem
https://stackoverflow.com/a/57400842/294884- the "border AND gap" problem
https://stackoverflow.com/a/57514286/294884- basic "adding" beziers

https://stackoverflow.com/a/57465440/294884- 图像 + 圆角 + 阴影
https://stackoverflow.com/a/41553784/294884- 两角问题
https://stackoverflow.com/a/59092828/294884- “阴影 + 孔”或“发光盒”问题
https://stackoverflow.com/a/57400842/294884- “边界和间隙”问题
https://stackoverflow.com/a/57514286/294884- 基本的“添加”贝塞尔曲线

回答by Angi

Extension to drop shadow and corner radius

投影和角半径的扩展

extension UIView {

func dropShadow(color: UIColor, opacity: Float = 0.5, offSet: CGSize, shadowRadius: CGFloat = 1, scale: Bool = true, cornerRadius: CGFloat) {
    let shadowLayer = CAShapeLayer()
    shadowLayer.path = UIBezierPath(roundedRect: bounds, cornerRadius: cornerRadius).cgPath
    shadowLayer.fillColor = UIColor.white.cgColor
    shadowLayer.shadowColor = color.cgColor
    shadowLayer.shadowPath = shadowLayer.path
    shadowLayer.shadowOffset = offSet
    shadowLayer.shadowOpacity = opacity
    shadowLayer.shadowRadius = shadowRadius
    layer.insertSublayer(shadowLayer, at: 0)
}

}

回答by Dhaval H. Nena

Here is the solution that will work!

这是有效的解决方案！

extension UIView {

    func applyShadowWithCornerRadius(color:UIColor, opacity:Float, radius: CGFloat, edge:AIEdge, shadowSpace:CGFloat)    {

        var sizeOffset:CGSize = CGSize.zero
        switch edge {
        case .Top:
            sizeOffset = CGSize(width: 0, height: -shadowSpace)
        case .Left:
            sizeOffset = CGSize(width: -shadowSpace, height: 0)
        case .Bottom:
            sizeOffset = CGSize(width: 0, height: shadowSpace)
        case .Right:
            sizeOffset = CGSize(width: shadowSpace, height: 0)


        case .Top_Left:
            sizeOffset = CGSize(width: -shadowSpace, height: -shadowSpace)
        case .Top_Right:
            sizeOffset = CGSize(width: shadowSpace, height: -shadowSpace)
        case .Bottom_Left:
            sizeOffset = CGSize(width: -shadowSpace, height: shadowSpace)
        case .Bottom_Right:
            sizeOffset = CGSize(width: shadowSpace, height: shadowSpace)


        case .All:
            sizeOffset = CGSize(width: 0, height: 0)
        case .None:
            sizeOffset = CGSize.zero
        }

        self.layer.cornerRadius = self.frame.size.height / 2
        self.layer.masksToBounds = true;

        self.layer.shadowColor = color.cgColor
        self.layer.shadowOpacity = opacity
        self.layer.shadowOffset = sizeOffset
        self.layer.shadowRadius = radius
        self.layer.masksToBounds = false

        self.layer.shadowPath = UIBezierPath(roundedRect:self.bounds, cornerRadius:self.layer.cornerRadius).cgPath
    }
}

enum AIEdge:Int {
    case
    Top,
    Left,
    Bottom,
    Right,
    Top_Left,
    Top_Right,
    Bottom_Left,
    Bottom_Right,
    All,
    None
}

Finally, to apply shadow with corner radius call as per below:

最后，应用具有角半径调用的阴影，如下所示：

viewRounded.applyShadowWithCornerRadius(color: .gray, opacity: 1, radius: 15, edge: AIEdge.All, shadowSpace: 15)

Result Image

结果图片