如何从自定义 UIView 类调用函数？

Question

我的第一个视图控制器中有 UIView。我已使用以下代码将该 UIView 类设置为自定义进度视图。

class ProgressView: UIView {
    let trackLayer = CAShapeLayer()
    let shapeLayer = CAShapeLayer()

    static let instance = ProgressView()

    override func awakeFromNib() {
        super.awakeFromNib()
        let center = CGPoint.init(x: frame.width / 2, y: frame.height / 2)
        let circularPath = UIBezierPath(arcCenter: center, radius: 30, startAngle: -CGFloat.pi / 2, endAngle: 2 * CGFloat.pi, clockwise: true)

        trackLayer.path = circularPath.cgPath
        trackLayer.strokeColor = #colorLiteral(red: 0.4745098054, green: 0.8392156959, blue: 0.9764705896, alpha: 1)
        trackLayer.lineWidth = 3
        trackLayer.fillColor = #colorLiteral(red: 0.5568627715, green: 0.3529411852, blue: 0.9686274529, alpha: 1)
        trackLayer.lineCap = kCALineCapRound
        self.layer.addSublayer(trackLayer)
        shapeLayer.path = circularPath.cgPath
        shapeLayer.strokeColor = #colorLiteral(red: 0.8078431487, green: 0.02745098062, blue: 0.3333333433, alpha: 1)
        shapeLayer.lineWidth = 3
        shapeLayer.fillColor = #colorLiteral(red: 0.3794638515, green: 0.5145698786, blue: 0.9605538249, alpha: 1)
        shapeLayer.lineCap = kCALineCapRound
        shapeLayer.strokeEnd = 0
        self.layer.addSublayer(shapeLayer)
    }
}

自定义 UIView 类中还有一个函数，用于启动动画以使用以下代码填充圆圈

 func startProgress() {
    let basicAnimation = CABasicAnimation(keyPath: "strokeEnd")
    basicAnimation.toValue = 1
    basicAnimation.duration = 60        
    basicAnimation.fillMode = kCAFillModeForwards
    basicAnimation.isRemovedOnCompletion = false
    shapeLayer.add(basicAnimation, forKey: "soBasic")
}

我需要在我的 First View 控制器中调用 startProgress 函数。在 viewDidLoad 我调用了 ProgressView.instance.startProgress() 但它没有触发。如何从另一个类调用启动进度函数？

Answer 1

在ProgressView你需要创建一个初始化或者你可以使用默认的。

class ProgressView: UIView {

    //you can set any additional properties in it.

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

    }

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

如何使用

在您想要使用的视图控制器中...

let pgView = ProgressView() //or any other initialise if you have created
.
.
.
pgView.startProgress()