完成上一条后如何多次绘制相同的贝塞尔路径？

Question

我正在使用贝塞尔路径、形状图层和 CABasicAnimation 来动画地绘制视图。但它只绘制一次视图。完成上一条后如何多次绘制相同的贝塞尔路径？

这是用于创建此类波形的附加代码。请检查...

类视图控制器：UIViewController {

@IBOutlet weak var scrollView: UIScrollView!
@IBOutlet weak var graphView: UIView!

// MARK:- PROPERTIES
var movingPoint: CGFloat = 0.0
var startInterval: CGFloat = 10.0
var noOfIntervals: CGFloat = 0
var intervalWidth: CGFloat = 0
var pWaveWidth: CGFloat = 20.0
var qrsWaveWidth: CGFloat = 15
var tWaveWidth: CGFloat = 30
var gapBetweenTwoIntervals: CGFloat = 50
let shapeLayer = CAShapeLayer()
var bezierPath = UIBezierPath()
let animation = CABasicAnimation(keyPath: "strokeEnd")



override func viewDidLoad() {
    super.viewDidLoad()
    
    graphView.translatesAutoresizingMaskIntoConstraints = true
    graphView.frame.size = CGSize(width: 100000, height: 150)
    DispatchQueue.main.async {
        self.graphView.layoutIfNeeded()
    }
}

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
    createGraph()
}


@objc func createGraph() {
    shapeLayer.fillColor = UIColor.clear.cgColor
    shapeLayer.strokeColor = UIColor.red.cgColor
    shapeLayer.lineWidth = 2.0
    _ = createBezierPath()
    graphView.layer.addSublayer(shapeLayer)
}

@discardableResult
@objc func createBezierPath(isPathAlreadyCreated: Bool = false) -> UIBezierPath {
    
    for _ in 0..<205 {
        let path = UIBezierPath()
        path.move(to: CGPoint(x: movingPoint, y: graphView.halfHeight))
        path.addLine(to: CGPoint(x: startInterval, y: graphView.halfHeight))
        
        // P Point Curve
        let pWaveX = startInterval + pWaveWidth
        path.addQuadCurve(to: CGPoint(x: pWaveX, y: graphView.halfHeight), controlPoint: CGPoint(x: pWaveX - 6.0, y: graphView.halfHeight - 30.0))
        
        let gapBetweenPAndQRS: CGFloat = 20.0
        path.addLine(to: CGPoint(x: (pWaveX + gapBetweenPAndQRS), y: graphView.halfHeight))
        
        // QRS
        let qrsStartPoint = pWaveX + gapBetweenPAndQRS
        let qrsComplex = qrsStartPoint + qrsWaveWidth
        let qrsComplexEndPoint = qrsComplex + (qrsWaveWidth / 2)
        path.addLine(to: CGPoint(x: qrsStartPoint + (qrsWaveWidth / 2), y: graphView.halfHeight - 70.0))
        path.addLine(to: CGPoint(x: qrsComplex, y: graphView.halfHeight + 40.0))
        path.addLine(to: CGPoint(x: qrsComplexEndPoint, y: graphView.halfHeight))
        
        let gapBetweenQRSAndTWave: CGFloat = 20.0
        let tWaveStartPoint = qrsComplexEndPoint + gapBetweenQRSAndTWave
        path.addLine(to: CGPoint(x: tWaveStartPoint, y: graphView.halfHeight))
        
        // T Point Curve
        let tWaveEndX = tWaveStartPoint + tWaveWidth
        print(tWaveEndX)
        path.addQuadCurve(to: CGPoint(x: tWaveEndX, y: graphView.halfHeight), controlPoint: CGPoint(x: tWaveEndX - 7.0, y: graphView.halfHeight - 30.0))
        
        movingPoint = tWaveEndX
        startInterval = tWaveEndX + gapBetweenTwoIntervals
        path.addLine(to: CGPoint(x: startInterval, y: graphView.halfHeight))
        bezierPath.append(path)
    }
    
    shapeLayer.path = bezierPath.cgPath
    
    animation.fromValue = 0.0
    animation.duration = 205 * 2
    shapeLayer.add(animation, forKey: "PathAnimation")
    
    return bezierPath
}

}

Answer 1

我设法解决了您的问题，请检查并告诉我它是否适合您。

注意 - 我添加了一个按钮单击以添加更多图形模式，而不是服务器响应。您可以通过从服务器响应成功方法调用按钮点击代码来使用服务器响应来执行相同的操作。

import UIKit

class GraphViewController: UIViewController {

@IBOutlet weak var graphView: UIView!

// MARK:- PROPERTIES
var movingPoint: CGFloat = 0.0
var startInterval: CGFloat = 10.0
var noOfIntervals: CGFloat = 0
var intervalWidth: CGFloat = 0
var pWaveWidth: CGFloat = 20.0
var qrsWaveWidth: CGFloat = 15
var tWaveWidth: CGFloat = 30
var gapBetweenTwoIntervals: CGFloat = 50
let animation = CABasicAnimation(keyPath: "strokeEnd")

override func viewDidLoad() {
    super.viewDidLoad()
    
    graphView.translatesAutoresizingMaskIntoConstraints = true
    graphView.backgroundColor = .blue
    graphView.frame.size = CGSize(width: 100000, height: 250)
    DispatchQueue.main.async {
        self.graphView.layoutIfNeeded()
    }
}

override func viewDidAppear(_ animated: Bool) {
    super.viewDidAppear(animated)
    createBezierPath(repeatLoop: 1)
}

@objc func createBezierPath(repeatLoop: Int) {
    let pathsArray = UIBezierPath()
    
    let shapeLayer = CAShapeLayer()
    shapeLayer.fillColor = UIColor.clear.cgColor
    shapeLayer.strokeColor = UIColor.red.cgColor
    shapeLayer.lineWidth = 2.0
    
    for _ in 0..<repeatLoop {
        let path = UIBezierPath()
        path.move(to: CGPoint(x: movingPoint, y: graphView.halfHeight))
        path.addLine(to: CGPoint(x: startInterval, y: graphView.halfHeight))
        
        // P Point Curve
        let pWaveX = startInterval + pWaveWidth
        path.addQuadCurve(to: CGPoint(x: pWaveX, y: graphView.halfHeight), controlPoint: CGPoint(x: pWaveX - 6.0, y: graphView.halfHeight - 30.0))
        
        let gapBetweenPAndQRS: CGFloat = 20.0
        path.addLine(to: CGPoint(x: (pWaveX + gapBetweenPAndQRS), y: graphView.halfHeight))
        
        // QRS
        let qrsStartPoint = pWaveX + gapBetweenPAndQRS
        let qrsComplex = qrsStartPoint + qrsWaveWidth
        let qrsComplexEndPoint = qrsComplex + (qrsWaveWidth / 2)
        path.addLine(to: CGPoint(x: qrsStartPoint + (qrsWaveWidth / 2), y: graphView.halfHeight - 70.0))
        path.addLine(to: CGPoint(x: qrsComplex, y: graphView.halfHeight + 40.0))
        path.addLine(to: CGPoint(x: qrsComplexEndPoint, y: graphView.halfHeight))
        
        let gapBetweenQRSAndTWave: CGFloat = 20.0
        let tWaveStartPoint = qrsComplexEndPoint + gapBetweenQRSAndTWave
        path.addLine(to: CGPoint(x: tWaveStartPoint, y: graphView.halfHeight))
        
        // T Point Curve
        let tWaveEndX = tWaveStartPoint + tWaveWidth
        print(tWaveEndX)
        path.addQuadCurve(to: CGPoint(x: tWaveEndX, y: graphView.halfHeight), controlPoint: CGPoint(x: tWaveEndX - 7.0, y: graphView.halfHeight - 30.0))
        
        movingPoint = tWaveEndX
        startInterval = tWaveEndX + gapBetweenTwoIntervals
        path.addLine(to: CGPoint(x: startInterval, y: graphView.halfHeight))
        pathsArray.append(path)
        
        shapeLayer.path = pathsArray.cgPath
        
        animation.fromValue = 0.0
        animation.duration = Double(repeatLoop) * 2
        shapeLayer.add(animation, forKey: "PathAnimation")
    }
    
    graphView.layer.addSublayer(shapeLayer)
}

@IBAction func btnTap(_ sender: Any) {
    createBezierPath(repeatLoop: 2)
}
}

extension UIView {
var halfHeight: CGFloat {
    return self.frame.size.height / 2.0
}
}

乐于助人:)