iOS Swift 앱의 배경보기에 그라디언트를 적용하는 방법

iOS Swift 앱의 배경보기에 그라디언트를 적용하는 방법

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그라디언트를 뷰의 배경색으로 적용하려고합니다 (스토리 보드의 주요 뷰). 코드는 실행되지만 아무 것도 변경되지 않습니다. xCode Beta 2와 Swift를 사용하고 있습니다.

코드는 다음과 같습니다.

class Colors {
  let colorTop = UIColor(red: 192.0/255.0, green: 38.0/255.0, blue: 42.0/255.0, alpha: 1.0)
  let colorBottom = UIColor(red: 35.0/255.0, green: 2.0/255.0, blue: 2.0/255.0, alpha: 1.0)

  let gl: CAGradientLayer

  init() {
    gl = CAGradientLayer()
    gl.colors = [ colorTop, colorBottom]
    gl.locations = [ 0.0, 1.0]
  }
}

그런 다음 뷰 컨트롤러에서

  let colors = Colors()

  func refresh() {
        view.backgroundColor = UIColor.clearColor()
        var backgroundLayer = colors.gl
        backgroundLayer.frame = view.frame
        view.layer.insertSublayer(backgroundLayer, atIndex: 0)
      }
    }
  }

---

그라디언트에 제공하는 색상은 유형이어야합니다 CGColor. 의 배열을 CGColor로 설정하십시오 gl.colors.

올바른 코드는 다음과 같습니다

class Colors {
    var gl:CAGradientLayer!

    init() {
        let colorTop = UIColor(red: 192.0 / 255.0, green: 38.0 / 255.0, blue: 42.0 / 255.0, alpha: 1.0).cgColor
        let colorBottom = UIColor(red: 35.0 / 255.0, green: 2.0 / 255.0, blue: 2.0 / 255.0, alpha: 1.0).cgColor

        self.gl = CAGradientLayer()
        self.gl.colors = [colorTop, colorBottom]
        self.gl.locations = [0.0, 1.0]
    }
}

---

Xcode 8.2 • 스위프트 3.0.2

---

다음과 같이 고유 한 그라디언트 뷰를 디자인 할 수 있습니다.

@IBDesignable
class GradientView: UIView {

    @IBInspectable var startColor:   UIColor = .black { didSet { updateColors() }}
    @IBInspectable var endColor:     UIColor = .white { didSet { updateColors() }}
    @IBInspectable var startLocation: Double =   0.05 { didSet { updateLocations() }}
    @IBInspectable var endLocation:   Double =   0.95 { didSet { updateLocations() }}
    @IBInspectable var horizontalMode:  Bool =  false { didSet { updatePoints() }}
    @IBInspectable var diagonalMode:    Bool =  false { didSet { updatePoints() }}

    override public class var layerClass: AnyClass { return CAGradientLayer.self }

    var gradientLayer: CAGradientLayer { return layer as! CAGradientLayer }

    func updatePoints() {
        if horizontalMode {
            gradientLayer.startPoint = diagonalMode ? CGPoint(x: 1, y: 0) : CGPoint(x: 0, y: 0.5)
            gradientLayer.endPoint   = diagonalMode ? CGPoint(x: 0, y: 1) : CGPoint(x: 1, y: 0.5)
        } else {
            gradientLayer.startPoint = diagonalMode ? CGPoint(x: 0, y: 0) : CGPoint(x: 0.5, y: 0)
            gradientLayer.endPoint   = diagonalMode ? CGPoint(x: 1, y: 1) : CGPoint(x: 0.5, y: 1)
        }
    }
    func updateLocations() {
        gradientLayer.locations = [startLocation as NSNumber, endLocation as NSNumber]
    }
    func updateColors() {
        gradientLayer.colors    = [startColor.cgColor, endColor.cgColor]
    }

    override public func layoutSubviews() {
        super.layoutSubviews()
        updatePoints()
        updateLocations()
        updateColors()
    }
}

---

그라디언트의 방향을 변경해야하는 경우 startPoint 및 endPoint를 사용해야합니다.

let gradient: CAGradientLayer = CAGradientLayer()

gradient.colors = [UIColor.blue.cgColor, UIColor.red.cgColor]
gradient.locations = [0.0 , 1.0]
gradient.startPoint = CGPoint(x: 0.0, y: 1.0)
gradient.endPoint = CGPoint(x: 1.0, y: 1.0)
gradient.frame = CGRect(x: 0.0, y: 0.0, width: self.view.frame.size.width, height: self.view.frame.size.height)

self.view.layer.insertSublayer(gradient, atIndex: 0)

---

위의 언급 답변을 수정하면됩니다.

func setGradientBackground() {
    let colorTop =  UIColor(red: 255.0/255.0, green: 149.0/255.0, blue: 0.0/255.0, alpha: 1.0).CGColor
    let colorBottom = UIColor(red: 255.0/255.0, green: 94.0/255.0, blue: 58.0/255.0, alpha: 1.0).CGColor

    let gradientLayer = CAGradientLayer()
    gradientLayer.colors = [colorTop, colorBottom]
    gradientLayer.locations = [0.0, 1.0]
    gradientLayer.frame = self.view.bounds

    self.view.layer.insertSublayer(gradientLayer, at:0)
}

그런 다음이 메소드를 호출하십시오. viewWillAppear

override func viewWillAppear(_ animated: Bool) {
    setGradientBackground()
    super.viewWillAppear(animated)
}

---

Swift3 에서 이것을 시도하십시오 :

 func addGradient(){

    let gradient:CAGradientLayer = CAGradientLayer()
    gradient.frame.size = self.viewThatHoldsGradient.frame.size
    gradient.colors = [UIColor.white.cgColor,UIColor.white.withAlphaComponent(0).cgColor] //Or any colors
    self.viewThatHoldsGradient.layer.addSublayer(gradient)

}

---

모든 뷰에 기본 그라디언트를 적용하기 위해 UIView 확장을 만들었습니다.

extension UIView {
    func layerGradient() {
        let layer : CAGradientLayer = CAGradientLayer()
        layer.frame.size = self.frame.size
        layer.frame.origin = CGPointMake(0.0,0.0)
        layer.cornerRadius = CGFloat(frame.width / 20)

        let color0 = UIColor(red:250.0/255, green:250.0/255, blue:250.0/255, alpha:0.5).CGColor
        let color1 = UIColor(red:200.0/255, green:200.0/255, blue: 200.0/255, alpha:0.1).CGColor
        let color2 = UIColor(red:150.0/255, green:150.0/255, blue: 150.0/255, alpha:0.1).CGColor
        let color3 = UIColor(red:100.0/255, green:100.0/255, blue: 100.0/255, alpha:0.1).CGColor
        let color4 = UIColor(red:50.0/255, green:50.0/255, blue:50.0/255, alpha:0.1).CGColor
        let color5 = UIColor(red:0.0/255, green:0.0/255, blue:0.0/255, alpha:0.1).CGColor
        let color6 = UIColor(red:150.0/255, green:150.0/255, blue:150.0/255, alpha:0.1).CGColor

        layer.colors = [color0,color1,color2,color3,color4,color5,color6]
        self.layer.insertSublayer(layer, atIndex: 0)
    }
}       

---

다음과 같은 확장 기능이 있습니다.

@IBDesignable class GradientView: UIView {
    @IBInspectable var firstColor: UIColor = UIColor.red
    @IBInspectable var secondColor: UIColor = UIColor.green

    @IBInspectable var vertical: Bool = true

    lazy var gradientLayer: CAGradientLayer = {
        let layer = CAGradientLayer()
        layer.colors = [firstColor.cgColor, secondColor.cgColor]
        layer.startPoint = CGPoint.zero
        return layer
    }()

    //MARK: -

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        applyGradient()
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

        applyGradient()
    }

    override func prepareForInterfaceBuilder() {
        super.prepareForInterfaceBuilder()
        applyGradient()
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        updateGradientFrame()
    }

    //MARK: -

    func applyGradient() {
        updateGradientDirection()
        layer.sublayers = [gradientLayer]
    }

    func updateGradientFrame() {
        gradientLayer.frame = bounds
    }

    func updateGradientDirection() {
        gradientLayer.endPoint = vertical ? CGPoint(x: 0, y: 1) : CGPoint(x: 1, y: 0)
    }
}

@IBDesignable class ThreeColorsGradientView: UIView {
    @IBInspectable var firstColor: UIColor = UIColor.red
    @IBInspectable var secondColor: UIColor = UIColor.green
    @IBInspectable var thirdColor: UIColor = UIColor.blue

    @IBInspectable var vertical: Bool = true {
        didSet {
            updateGradientDirection()
        }
    }

    lazy var gradientLayer: CAGradientLayer = {
        let layer = CAGradientLayer()
        layer.colors = [firstColor.cgColor, secondColor.cgColor, thirdColor.cgColor]
        layer.startPoint = CGPoint.zero
        return layer
    }()

    //MARK: -

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)

        applyGradient()
    }

    override init(frame: CGRect) {
        super.init(frame: frame)

        applyGradient()
    }

    override func prepareForInterfaceBuilder() {
        super.prepareForInterfaceBuilder()
        applyGradient()
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        updateGradientFrame()
    }

    //MARK: -

    func applyGradient() {
        updateGradientDirection()
        layer.sublayers = [gradientLayer]
    }

    func updateGradientFrame() {
        gradientLayer.frame = bounds
    }

    func updateGradientDirection() {
        gradientLayer.endPoint = vertical ? CGPoint(x: 0, y: 1) : CGPoint(x: 1, y: 0)
    }
}

@IBDesignable class RadialGradientView: UIView {

    @IBInspectable var outsideColor: UIColor = UIColor.red
    @IBInspectable var insideColor: UIColor = UIColor.green

    override func awakeFromNib() {
        super.awakeFromNib()

        applyGradient()
    }

    func applyGradient() {
        let colors = [insideColor.cgColor, outsideColor.cgColor] as CFArray
        let endRadius = sqrt(pow(frame.width/2, 2) + pow(frame.height/2, 2))
        let center = CGPoint(x: bounds.size.width / 2, y: bounds.size.height / 2)
        let gradient = CGGradient(colorsSpace: nil, colors: colors, locations: nil)
        let context = UIGraphicsGetCurrentContext()

        context?.drawRadialGradient(gradient!, startCenter: center, startRadius: 0.0, endCenter: center, endRadius: endRadius, options: CGGradientDrawingOptions.drawsBeforeStartLocation)
    }

    override func draw(_ rect: CGRect) {
        super.draw(rect)

        #if TARGET_INTERFACE_BUILDER
            applyGradient()
        #endif
    }
}

용법:

---

이것을 시도하십시오, 그것은 나를 위해 일하고 있습니다.

  var gradientView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 35))
  let gradientLayer:CAGradientLayer = CAGradientLayer()
  gradientLayer.frame.size = self.gradientView.frame.size
  gradientLayer.colors = 
  [UIColor.white.cgColor,UIColor.red.withAlphaComponent(1).cgColor] 
  //Use diffrent colors
  gradientView.layer.addSublayer(gradientLayer)

그라디언트 색상의 시작점과 끝점을 추가 할 수 있습니다.

    gradientLayer.startPoint = CGPoint(x: 0.0, y: 1.0)
    gradientLayer.endPoint = CGPoint(x: 1.0, y: 1.0)

자세한 내용은 Best Answer를 참조 하거나 Apple의 CAGradientLayer 를 팔로우 하십시오.

희망 이것은 누군가에게 도움이됩니다.

---

UIView이 사용자 정의 클래스로 확장하십시오 .

---

GradientView.swift

import UIKit

class GradientView: UIView {

    // Default Colors
    var colors:[UIColor] = [UIColor.redColor(), UIColor.blueColor()]

    override func drawRect(rect: CGRect) {

        // Must be set when the rect is drawn
        setGradient(colors[0], color2: colors[1])
    }

    func setGradient(color1: UIColor, color2: UIColor) {

        let context = UIGraphicsGetCurrentContext()
        let gradient = CGGradientCreateWithColors(CGColorSpaceCreateDeviceRGB(), [color1.CGColor, color2.CGColor], [0, 1])!

        // Draw Path
        let path = UIBezierPath(rect: CGRectMake(0, 0, frame.width, frame.height))
        CGContextSaveGState(context)
        path.addClip()
        CGContextDrawLinearGradient(context, gradient, CGPointMake(frame.width / 2, 0), CGPointMake(frame.width / 2, frame.height), CGGradientDrawingOptions())
        CGContextRestoreGState(context)
    }

    override func layoutSubviews() {

        // Ensure view has a transparent background color (not required)
        backgroundColor = UIColor.clearColor()
    }

}

---

용법

gradientView.colors = [UIColor.blackColor().colorWithAlphaComponent(0.8), UIColor.clearColor()]

---

결과

---

그것은 간단합니다

    // MARK: - Gradient
extension CAGradientLayer {
    enum Point {
        case topLeft
        case centerLeft
        case bottomLeft
        case topCenter
        case center
        case bottomCenter
        case topRight
        case centerRight
        case bottomRight
        var point: CGPoint {
            switch self {
            case .topLeft:
                return CGPoint(x: 0, y: 0)
            case .centerLeft:
                return CGPoint(x: 0, y: 0.5)
            case .bottomLeft:
                return CGPoint(x: 0, y: 1.0)
            case .topCenter:
                return CGPoint(x: 0.5, y: 0)
            case .center:
                return CGPoint(x: 0.5, y: 0.5)
            case .bottomCenter:
                return CGPoint(x: 0.5, y: 1.0)
            case .topRight:
                return CGPoint(x: 1.0, y: 0.0)
            case .centerRight:
                return CGPoint(x: 1.0, y: 0.5)
            case .bottomRight:
                return CGPoint(x: 1.0, y: 1.0)
            }
        }
    }
    convenience init(start: Point, end: Point, colors: [CGColor], type: CAGradientLayerType) {
        self.init()
        self.startPoint = start.point
        self.endPoint = end.point
        self.colors = colors
        self.locations = (0..<colors.count).map(NSNumber.init)
        self.type = type
    }
}

다음과 같이 사용하십시오 :-

let fistColor = UIColor.white
let lastColor = UIColor.black
let gradient = CAGradientLayer(start: .topLeft, end: .topRight, colors: [fistColor.cgColor, lastColor.cgColor], type: .radial)
gradient.frame = yourView.bounds
yourView.layer.addSublayer(gradient)

---

이 코드는 Swift 3.0에서 작동합니다

class GradientView: UIView {

    override open class var layerClass: AnyClass {
        get{
            return CAGradientLayer.classForCoder()
        }
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        let gradientLayer = self.layer as! CAGradientLayer
        let color1 = UIColor.white.withAlphaComponent(0.1).cgColor as CGColor
        let color2 = UIColor.white.withAlphaComponent(0.9).cgColor as CGColor
        gradientLayer.locations = [0.60, 1.0]
        gradientLayer.colors = [color2, color1]
    }
}

---

스위프트 4

뷰 콘센트 추가

@IBOutlet weak var gradientView: UIView!

뷰에 그라디언트 추가

func setGradient() {
    let gradient: CAGradientLayer = CAGradientLayer()
    gradient.colors = [UIColor.red.cgColor, UIColor.blue.cgColor]
    gradient.locations = [0.0 , 1.0]
    gradient.startPoint = CGPoint(x: 0.0, y: 1.0)
    gradient.endPoint = CGPoint(x: 1.0, y: 1.0)
    gradient.frame = gradientView.layer.frame
    gradientView.layer.insertSublayer(gradient, at: 0)
}

---

RGBA 대신 HEX를 사용하려면 비어있는 새 .swift를 드래그하여 아래에 언급 된 코드를 추가하십시오.

     import UIKit

    extension UIColor {
        convenience init(rgba: String) {
            var red:   CGFloat = 0.0
            var green: CGFloat = 0.0
            var blue:  CGFloat = 0.0
            var alpha: CGFloat = 1.0

            if rgba.hasPrefix("#") {
                let index   = advance(rgba.startIndex, 1)
                let hex     = rgba.substringFromIndex(index)
                let scanner = NSScanner(string: hex)
                var hexValue: CUnsignedLongLong = 0
                if scanner.scanHexLongLong(&hexValue) {
                    switch (count(hex)) {
                    case 3:
                        red   = CGFloat((hexValue & 0xF00) >> 8)       / 15.0
                        green = CGFloat((hexValue & 0x0F0) >> 4)       / 15.0
                        blue  = CGFloat(hexValue & 0x00F)              / 15.0
                    case 4:
                        red   = CGFloat((hexValue & 0xF000) >> 12)     / 15.0
                        green = CGFloat((hexValue & 0x0F00) >> 8)      / 15.0
                        blue  = CGFloat((hexValue & 0x00F0) >> 4)      / 15.0
                        alpha = CGFloat(hexValue & 0x000F)             / 15.0
                    case 6:
                        red   = CGFloat((hexValue & 0xFF0000) >> 16)   / 255.0
                        green = CGFloat((hexValue & 0x00FF00) >> 8)    / 255.0
                        blue  = CGFloat(hexValue & 0x0000FF)           / 255.0
                    case 8:
                        red   = CGFloat((hexValue & 0xFF000000) >> 24) / 255.0
                        green = CGFloat((hexValue & 0x00FF0000) >> 16) / 255.0
                        blue  = CGFloat((hexValue & 0x0000FF00) >> 8)  / 255.0
                        alpha = CGFloat(hexValue & 0x000000FF)         / 255.0
                    default:
                        print("Invalid RGB string, number of characters after '#' should be either 3, 4, 6 or 8")
                    }
                } else {
                    println("Scan hex error")
                }
            } else {
                print("Invalid RGB string, missing '#' as prefix")
            }
            self.init(red:red, green:green, blue:blue, alpha:alpha)
        }
}

마찬가지로, 비어있는 다른 .swift 파일을 드래그하여 아래에 언급 된 코드를 추가하십시오.

    class Colors {
    let colorTop = UIColor(rgba: "##8968CD").CGColor
    let colorBottom = UIColor(rgba: "#5D478B").CGColor

    let gl: CAGradientLayer

    init() {
        gl = CAGradientLayer()
        gl.colors = [ colorTop, colorBottom]
        gl.locations = [ 0.0, 1.0]
    }
}

그 후 뷰 컨트롤러에서 클래스 아래에서 다음과 같이 'Color'클래스를 인스턴스화하십시오.

let colors = Colors()

새로운 기능을 추가하십시오 :

func refresh() {
        view.backgroundColor = UIColor.clearColor()
        var backgroundLayer = colors.gl
        backgroundLayer.frame = view.frame
        view.layer.insertSublayer(backgroundLayer, atIndex: 0)
    }

viewDidLoad의 해당 기능 상태 :

refresh()

RGBA와 비교하면 HEX를 사용하는 것이 너무 쉽습니다. :디

---

스위프트 3-텍스처와 SKSpriteNode 만 사용하고 UIView가 필요하지 않음

import Foundation
import SpriteKit

class GradientSpriteNode : SKSpriteNode
{
    convenience init(size: CGSize, colors: [UIColor], locations: [CGFloat])
    {
        let texture = GradientSpriteNode.texture(size: size, colors: colors, locations: locations)
        self.init(texture: texture, color:SKColor.clear, size: texture.size())
    }

    private override init(texture: SKTexture!, color: SKColor, size: CGSize) {
        super.init(texture: texture, color: color, size: size)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    private static func texture(size: CGSize, colors: [UIColor], locations: [CGFloat]) -> SKTexture
    {
        UIGraphicsBeginImageContext(size)
        let context = UIGraphicsGetCurrentContext()!
        let gradient = CGGradient(colorsSpace: CGColorSpaceCreateDeviceRGB(), colors: colors.map{$0.cgColor} as CFArray, locations: locations)!
        context.drawLinearGradient(gradient, start: CGPoint(x: size.width / 2, y: 0), end: CGPoint(x: size.width / 2, y: size.height), options: CGGradientDrawingOptions())
        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        return SKTexture(image: image!)

    }
}

용법:

let gradient = GradientSpriteNode(
        size: CGSize(width: 100, height: 100),
        colors: [UIColor.red, UIColor.blue],
        locations: [0.0, 1.0])
addChild(gradient)

---

모든 객체 (가로 및 세로)에 CAGradientLayer를 신속하게 적용

func makeGradientColor(`for` object : AnyObject , startPoint : CGPoint , endPoint : CGPoint) -> CAGradientLayer {
    let gradient: CAGradientLayer = CAGradientLayer()

    gradient.colors = [(UIColor(red: 59.0/255.0, green: 187.0/255.0, blue: 182.0/255.0, alpha: 1.00).cgColor), (UIColor(red: 57.0/255.0, green: 174.0/255.0, blue: 236.0/255.0, alpha: 1.00).cgColor)]
    gradient.locations = [0.0 , 1.0]

    gradient.startPoint = startPoint
    gradient.endPoint = endPoint
    gradient.frame = CGRect(x: 0.0, y: 0.0, width: object.frame.size.width, height: object.frame.size.height)
    return gradient
}

사용하는 방법

let start : CGPoint = CGPoint(x: 0.0, y: 1.0)
let end : CGPoint = CGPoint(x: 1.0, y: 1.0)
let gradient: CAGradientLayer = self.makeGradientColor(for: vwTop, startPoint: start, endPoint: end)
vwTop.layer.insertSublayer(gradient, at: 0)

let start1 : CGPoint = CGPoint(x: 1.0, y: 1.0)
let end1 : CGPoint = CGPoint(x: 1.0, y: 0.0)
let gradient1: CAGradientLayer = self.makeGradientColor(for: vwTop, startPoint: start1, endPoint: end1)
vwBottom.layer.insertSublayer(gradient1, at: 0)

여기서 출력을 확인할 수 있습니다

---

다음은 임의의 색상을 원하는대로 전달할 수있는 빠른 확장 기능입니다. 삽입하기 전에 이전 그라디언트를 제거하고 필요한 경우 추가 조작을 위해 새로 삽입 된 그라디언트 레이어를 반환합니다.

    extension UIView {

    /**
     Given an Array of CGColor, it will:
        - Remove all sublayers of type CAGradientLayer.
        - Create and insert a new CAGradientLayer.

     - Parameters: 
        - colors: An Array of CGColor with the colors for the gradient fill

     - Returns: The newly created gradient CAGradientLayer
     */
    func layerGradient(colors c:[CGColor])->CAGradientLayer {
        self.layer.sublayers = self.layer.sublayers?.filter(){!($0 is CAGradientLayer)}
        let layer : CAGradientLayer = CAGradientLayer()
        layer.frame.size = self.frame.size
        layer.frame.origin = CGPointZero
        layer.colors = c
        self.layer.insertSublayer(layer, atIndex: 0)
        return layer
    }
}

---

그래디언트 색상을 표시하려는보기의 프레임을 지정하십시오.

let firstColor =  UIColor(red: 69/255, green: 90/255, blue: 195/255, alpha: 1.0).CGColor

 let secondColor = UIColor(red: 230/255, green: 44/255, blue: 75/255, alpha: 1.0).CGColor

    let gradientLayer = CAGradientLayer()
    gradientLayer.colors = [ firstColor, secondColor]
    gradientLayer.locations = [ 0.0, 1.0]
    gradientLayer.frame = CGRectMake(0, 0, 375, 64)// You can mention frame here

    self.view.layer.addSublayer(gradientLayer)

---

클래스 UIColor의 인스턴스에 아무것도 전달할 수있는보다 깨끗한 코드 GradientLayer:

class GradientLayer {

    let gradientLayer: CAGradientLayer
    let colorTop: CGColor
    let colorBottom: CGColor

    init(colorTop: UIColor, colorBottom: UIColor) {
        self.colorTop = colorTop.CGColor
        self.colorBottom = colorBottom.CGColor
        gradientLayer = CAGradientLayer()
        gradientLayer.colors = [colorTop, colorBottom]
        gradientLayer.locations = [0.0, 1.0]
    }
}

---

재사용 가능한 Util 클래스 파일에서 이것을 설정하는 변형이 있습니다.

Xcode 프로젝트에서 :

1. 새 Swift 클래스를 UI_Util.swift라고 작성하고 다음과 같이 채우십시오.

   import Foundation
   import UIKit
   
   class UI_Util {
   
       static func setGradientGreenBlue(uiView: UIView) {
   
           let colorTop =  UIColor(red: 15.0/255.0, green: 118.0/255.0, blue: 128.0/255.0, alpha: 1.0).cgColor
           let colorBottom = UIColor(red: 84.0/255.0, green: 187.0/255.0, blue: 187.0/255.0, alpha: 1.0).cgColor
   
           let gradientLayer = CAGradientLayer()
           gradientLayer.colors = [ colorTop, colorBottom]
           gradientLayer.locations = [ 0.0, 1.0]
           gradientLayer.frame = uiView.bounds
   
           uiView.layer.insertSublayer(gradientLayer, at: 0)
       }
   }
   

---

2. 이제 다음과 같이 ViewController에서 함수를 호출 할 수 있습니다.

   class AbcViewController: UIViewController {
   
       override func viewDidLoad() {
           super.viewDidLoad()                
           UI_Util.setGradientGreen(uiView: self.view)
       }                
   

기능 코드에 대한 katwal-Dipak의 답변 덕분에

---

신속한 3에 확장 사용하기 쉬운

extension CALayer {
    func addGradienBorder(colors:[UIColor] = [UIColor.red,UIColor.blue], width:CGFloat = 1) {
        let gradientLayer = CAGradientLayer()
        gradientLayer.frame =  CGRect(origin: .zero, size: self.bounds.size)
        gradientLayer.startPoint = CGPoint(x:0.0, y:0.5)
        gradientLayer.endPoint = CGPoint(x:1.0, y:0.5)
        gradientLayer.colors = colors.map({$0.cgColor})

        let shapeLayer = CAShapeLayer()
        shapeLayer.lineWidth = width
        shapeLayer.path = UIBezierPath(rect: self.bounds).cgPath
        shapeLayer.fillColor = nil
        shapeLayer.strokeColor = UIColor.black.cgColor
        gradientLayer.mask = shapeLayer

        self.addSublayer(gradientLayer)
    }
}

당신의 견해에 사용, 예

yourView.addGradienBorder(color: UIColor.black, opacity: 0.1, offset: CGSize(width:2 , height: 5), radius: 3, viewCornerRadius: 3.0)

---

View Collection (Multiple View)이 있다면 이것을하십시오.

  func setGradientBackground() {
    let v:UIView
    for v in viewgradian
    //here viewgradian is your view Collection Outlet name
    {
        let layer:CALayer
        var arr = [AnyObject]()
        for layer in v.layer.sublayers!
        {
           arr.append(layer)
        }

        let colorTop = UIColor(red: 216.0/255.0, green: 240.0/255.0, blue: 244.0/255.0, alpha: 1.0).cgColor
        let colorBottom = UIColor(red: 255.0/255.0, green: 255.0/255.0, blue: 255.0/255.0, alpha: 1.0).cgColor
        let gradientLayer = CAGradientLayer()
        gradientLayer.colors = [ colorBottom, colorTop]
        gradientLayer.startPoint = CGPoint(x: 1.0, y: 0.0)
        gradientLayer.endPoint = CGPoint(x: 0.0, y: 1.0)
        gradientLayer.frame = v.bounds
        v.layer.insertSublayer(gradientLayer, at: 0)
    }
}

---

뷰에 그라디언트를 추가하고 자동 레이아웃을 사용하여 고정하고 싶었습니다.

    class GradientView: UIView {

    private let gradient: CAGradientLayer = {
        let layer = CAGradientLayer()
        let topColor: UIColor = UIColor(red:0.98, green:0.96, blue:0.93, alpha:0.5)
        let bottomColor: UIColor = UIColor.white
        layer.colors = [topColor.cgColor, bottomColor.cgColor]
        layer.locations = [0,1]
        return layer
    }()

    init() {
        super.init(frame: .zero)
        gradient.frame = frame
        layer.insertSublayer(gradient, at: 0)
    }

    required init?(coder aDecoder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        gradient.frame = bounds

    }
}

---

그라디언트 색상에 사용할 수있는 Chameleon ( https://github.com/viccalexander/Chameleon ) 이라는 라이브러리가 있습니다. 구현할 그라디언트 스타일도 있습니다. 이것은 swift 4 podfile 팟 'ChameleonFramework / Swift', : git => ' https://github.com/ViccAlexander/Chameleon.git ', : branch => 'wip / swift4'에 추가하는 방법입니다.

import ChameleonFramework

let colors:[UIColor] = [
  UIColor.flatPurpleColorDark(), 
  UIColor.flatWhiteColor()
]
view.backgroundColor = GradientColor(.TopToBottom, frame: view.frame, colors: colors)

---

아래 코드를 사용하십시오 :

extension UIView {
func applyGradient(colours: [UIColor]) -> Void {
 let gradient: CAGradientLayer = CAGradientLayer()
 gradient.frame = self.bounds
 gradient.colors = colours.map { $0.cgColor }
 gradient.startPoint = CGPoint(x : 0.0, y : 0.5)
 gradient.endPoint = CGPoint(x :1.0, y: 0.5)
 self.layer.insertSublayer(gradient, at: 0)
 }
}

이 함수를 다음과 같이 호출하십시오.

  self.mainView.applyGradient(colours: [.green, .blue])

---

레이어에 그라디언트를 추가하려면 다음을 추가하십시오.

let layer = CAGradientLayer()
layer.frame = CGRect(x: 64, y: 64, width: 120, height: 120)
layer.colors = [UIColor.red.cgColor, UIColor.blue.cgColor]
view.layer.addSublayer(layer)

참고 URL : https://stackoverflow.com/questions/24380535/how-to-apply-gradient-to-background-view-of-ios-swift-app