swift - layer - 渐变色 - CAGradientLayer

知道控件的frame ,创建控件时候直接加上 渐变色

    // 创建背景渐变色button(通用于View or Controller底部按钮),bounds计算后传入
static func createGradientButton(font: UIFont = UIFont.systemFont(ofSize: 14), textColor: UIColor = UIColor.white, titleStr: String? = nil,bounds:CGRect) -> UIbutton {
let btn = UIButton(type: .custom)
btn.translatesAutoresizingMaskIntoConstraints = false
btn.setTitle(titleStr, for: .normal)
btn.titleLabel?.font = font
btn.setTitleColor(textColor, for: .normal)
btn.backgroundColor = UIColor.clear
let caGradientLayer:CAGradientLayer = CAGradientLayer()
caGradientLayer.colors = [UIColor(hexString: "#E0AD7D").cgColor,UIColor(hexString: "#FFE8C9").cgColor]
caGradientLayer.locations = [0, 1]
caGradientLayer.startPoint = CGPoint(x: 0, y: 1)
caGradientLayer.endPoint = CGPoint(x: 0.8, y: 1)
caGradientLayer.frame = bounds
btn.layer.insertSublayer(caGradientLayer, at: 0)
return btn
}

  

2. 不知道 frame

1。创建 渐变色

   /// 渐变色:默认从上到下
private var gradientLayer: CAGradientLayer = {
let g = CAGradientLayer()
g.colors = [UIColor.init(hexColor: "DBB479").cgColor,
UIColor.init(hexColor: "F7E1B3").cgColor]
//改为从左到右 的渐变
g.startPoint = CGPoint(x: 0, y: 0)
g.endPoint = CGPoint(x: 1, y: 0)
return g
}()

  

2.给指定view 添加渐变色

    /// 荣誉背景图
private lazy var credibilityBgView : UIView = {
let v = UIView()
v.layer.addSublayer(self.gradientLayer)
v.translatesAutoresizingMaskIntoConstraints = false
v.layer.cornerRadius = 5
v.layer.masksToBounds = true
v.isUserInteractionEnabled = true
v.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(clcikCredibilityBgView)))
return v
}()

  

3. 在自定义的view中 设置 渐变色frame:draw

    override func draw(_ rect: CGRect) {
super.draw(rect)
gradientLayer.frame = credibilityBgView.bounds
}

4.如果在控制器里面,viewDidLayoutSubviews

 override func viewDidLayoutSubviews() {
super.viewDidLayoutSubviews()
nextBtnAddLayer()
} /// 下一步按钮添加渐变色
func nextBtnAddLayer(){
let gradient = CAGradientLayer()
gradient.colors = [UIColor.init(hexString: "#FD904B").cgColor,
UIColor.init(hexString: "#FFA64D").cgColor ]
//改为从左到右 的渐变
gradient.startPoint = CGPoint(x: 0, y: 0)
gradient.endPoint = CGPoint(x: 1, y: 0)
nextBtn.layer.insertSublayer(gradient, at: 0)
gradient.frame = nextBtn.bounds
}

  

注意 直接用addSubLayer 会遮盖住 子控件, 使用insertSublayer 不会有问题

  

swift - layer - 渐变色 - CAGradientLayer

上面 是同一个渐变色的 colors 更换,

    //渐变色
private lazy var caGradientLayer : CAGradientLayer = {
let caGradientLayer:CAGradientLayer = CAGradientLayer()
caGradientLayer.colors = []
caGradientLayer.locations = [0, 1]
caGradientLayer.startPoint = CGPoint(x: 0, y: 1)
caGradientLayer.endPoint = CGPoint(x: 0.8, y: 1)
return caGradientLayer
}() /// 渐变色颜色
private lazy var cgColors: (normal: [CGColor] , select: [CGColor] ) = ([] , []) /// 渐变色 更改 颜色
/// - Parameters:
/// - basicAnimationKeyPath: 动画对应的唯一标示
/// - animationKey: 渐变色 添加的 动画 唯一标示
/// - toChangeColors: 改变的颜色数组
/// - duration: 动画时间
private func addAnimationForCaGradientLayer(basicAnimationKeyPath:String,
animationKey:String,
toChangeColors:[CGColor],
durationTime:CFTimeInterval = 0.05){
//添加渐变动画
let colorChangeAnimation = CABasicAnimation(keyPath: basicAnimationKeyPath)
colorChangeAnimation.delegate = self
colorChangeAnimation.duration = durationTime
colorChangeAnimation.toValue = toChangeColors
colorChangeAnimation.fillMode = CAMediaTimingFillMode .forwards
colorChangeAnimation.isRemovedOnCompletion = false
caGradientLayer.add(colorChangeAnimation, forKey: animationKey)
} 开始定时器是
self.addAnimationForCaGradientLayer(basicAnimationKeyPath: "colorSelected", animationKey: "colorChangeToSelected", toChangeColors: self.cgColors.select) 然后倒计时结束的时候
self.setTitle("重新发送", for: .normal)
self.addAnimationForCaGradientLayer(basicAnimationKeyPath: "colorNormal", animationKey: "colorChangeToNormal", toChangeColors: self.cgColors.normal)

  

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