ios - 子层未按预期隐藏/显示

Question

我有一个自定义按钮，其中包含一些在 draw(_ rect: CGRect) 中添加的 CAShapeLayer。我希望在 recording 为 true 时隐藏 circleLayer；但是，仅当 recording 设置为 false 后，circleLayer 才会隐藏。

我注意到的一些其他症状:

1. circleLayer 第一次正确隐藏/显示(当 View 首次加载时)
2. 如果我呈现模态视图 Controller 然后关闭模态视图 Controller ，此行为会自行纠正。

由于如果呈现模态视图 Controller 然后将其关闭，此问题会自行纠正，因此我相信这只是 View 未正确重绘自身的问题。但是，我似乎无法修复它。

如有任何帮助，我们将不胜感激。

class RecordButton: TouchAnimationButton {

var recording: Bool = false {
    didSet {
        self.setNeedsDisplay()
    }
}

private static let ringLayerLineWidthRatio: CGFloat = 0.1
private static let separatorWidthRatio: CGFloat = 0.2
private static let squareLayerCornerRadiusRatio: CGFloat = 0.1

lazy var ringLayer: CAShapeLayer = {
    let layer = CAShapeLayer()
    layer.path = UIBezierPath().cgPath
    layer.speed = 0.0
    layer.strokeColor = UIColor.white.cgColor
    layer.fillColor = UIColor.clear.cgColor
    return layer
}()

lazy var circleLayer: CAShapeLayer = {
    let layer = CAShapeLayer()
    layer.path = UIBezierPath().cgPath
    layer.speed = 0.0
    layer.fillColor = UIColor.red.cgColor
    layer.strokeColor = UIColor.clear.cgColor
    layer.lineWidth = 0.0
    return layer
}()

lazy var squarePath: CAShapeLayer = {
    let layer = CAShapeLayer()
    layer.path = UIBezierPath().cgPath
    layer.speed = 0.0
    layer.fillColor = UIColor.red.cgColor
    layer.strokeColor = UIColor.clear.cgColor
    layer.lineWidth = 0.0
    return layer
}()

func getCirclePath() -> UIBezierPath {
    let radius = (getMinDim() - getRingLayerLineWidth() - getSeparatorWidth()) / 2.0
    let center = CGPoint(x: self.bounds.size.width / 2.0, y: self.bounds.size.height / 2.0)

    let path = UIBezierPath()
    path.addArc(withCenter: center, radius: radius, startAngle: 0, endAngle: CGFloat(2 * Double.pi), clockwise: true)
    return path
}

func getRingPath() -> UIBezierPath {
    let center = CGPoint(x: self.bounds.size.width / 2.0, y: self.bounds.size.height / 2.0)
    let radius = (getMinDim() - getRingLayerLineWidth()) / 2.0

    let path = UIBezierPath()
    path.addArc(withCenter: center, radius: radius, startAngle: 0, endAngle: CGFloat(2 * Double.pi), clockwise: true)
    return path
}

func getSquarePath() -> UIBezierPath {
    let radius = (getMinDim() - getRingLayerLineWidth() - 1.5 * getSeparatorWidth()) / 2.0
    let center = CGPoint(x: self.bounds.size.width / 2.0, y: self.bounds.size.height / 2.0)
    let cornerRadius = RecordButton.squareLayerCornerRadiusRatio * getMinDim()
    let side = sqrt(2) * radius
    let halfSide = side / 2.0

    let path = UIBezierPath()
    path.move(to: CGPoint(x: center.x - halfSide + cornerRadius , y: center.y - halfSide))
    path.addLine(to: CGPoint(x: center.x + halfSide - cornerRadius, y: center.y - halfSide))
    path.addArc(withCenter: CGPoint(x: center.x + halfSide - cornerRadius, y: center.y - halfSide + cornerRadius),
                radius: cornerRadius,
                startAngle: CGFloat(3.0 * Double.pi / 2.0),
                endAngle: CGFloat(2.0 * Double.pi),
                clockwise: true)
    path.addLine(to: CGPoint(x: center.x + halfSide, y: center.y + halfSide - cornerRadius))
    path.addArc(withCenter: CGPoint(x: center.x + halfSide - cornerRadius, y: center.y + halfSide - cornerRadius),
                radius: cornerRadius,
                startAngle: CGFloat(0),
                endAngle: CGFloat(Double.pi / 2.0),
                clockwise: true)
    path.addLine(to: CGPoint(x: center.x - halfSide + cornerRadius, y: center.y + halfSide))
    path.addArc(withCenter: CGPoint(x: center.x - halfSide + cornerRadius, y: center.y + halfSide - cornerRadius),
                radius: cornerRadius,
                startAngle: CGFloat(Double.pi / 2.0),
                endAngle: CGFloat(Double.pi),
                clockwise: true)
    path.addLine(to: CGPoint(x: center.x - halfSide, y: center.y - halfSide + cornerRadius))
    path.addArc(withCenter: CGPoint(x: center.x - halfSide + cornerRadius, y: center.y - halfSide + cornerRadius),
                radius: cornerRadius,
                startAngle: CGFloat(Double.pi),
                endAngle: CGFloat(3.0 * Double.pi / 2.0),
                clockwise: true)
    return path
}

func getMinDim() -> CGFloat {
    return min(self.bounds.size.width, self.bounds.size.height)
}

func getRingLayerLineWidth() -> CGFloat {
    return RecordButton.ringLayerLineWidthRatio * getMinDim()
}

func getSeparatorWidth() -> CGFloat {
    return RecordButton.separatorWidthRatio * getMinDim()
}

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

    if self.squarePath.superlayer == nil {
        self.layer.addSublayer(self.squarePath)
    }

    if self.circleLayer.superlayer == nil {
        self.layer.addSublayer(self.circleLayer)
    }

    if self.ringLayer.superlayer == nil {
        self.layer.addSublayer(self.ringLayer)
    }

    self.ringLayer.lineWidth = getRingLayerLineWidth()

    self.ringLayer.path = self.getRingPath().cgPath
    self.circleLayer.path = self.getCirclePath().cgPath
    self.squarePath.path = self.getSquarePath().cgPath

    self.circleLayer.isHidden = self.recording
}
}

class TouchAnimationButton: UIButton {

private static let transformAnimationTime = 0.15

private var initialTransform: CGAffineTransform? = nil

override func layoutSubviews() {
    super.layoutSubviews()

    self.layer.minificationFilter = kCAFilterTrilinear
    if initialTransform == nil {
        initialTransform = self.layer.affineTransform()
    }
}

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) {
    super.touchesBegan(touches, with: event)
    weak var weakSelf = self
    UIView.animate(withDuration: TouchAnimationButton.transformAnimationTime, animations: {
        guard let view = weakSelf, let initialTransform = view.initialTransform else {
            return
        }
        view.layer.setAffineTransform(initialTransform.scaledBy(x: 0.9, y: 0.9))
    })
}

override func touchesMoved(_ touches: Set<UITouch>, with event: UIEvent?) {
    super.touchesMoved(touches, with: event)

    weak var weakSelf = self
    if let point = touches.first?.location(in: self),
        self.bounds.contains(point) {
        weak var weakSelf = self
        self.layer.shouldRasterize = true
        UIView.animate(withDuration: TouchAnimationButton.transformAnimationTime, animations: {
            guard let view = weakSelf, let initialTransform = view.initialTransform else {
                return
            }
            view.layer.setAffineTransform(initialTransform.scaledBy(x: 0.9, y: 0.9))
        })
    } else {
        UIView.animate(withDuration: TouchAnimationButton.transformAnimationTime, animations: {
            guard let view = weakSelf, let initialTransform = view.initialTransform else {
                return
            }
            view.layer.setAffineTransform(initialTransform)
        }, completion: { finished in
            weakSelf?.contentScaleFactor = UIScreen.main.scale
        })
    }
}

override func touchesEnded(_ touches: Set<UITouch>, with event: UIEvent?) {
    super.touchesEnded(touches, with: event)
    weak var weakSelf = self
    UIView.animate(withDuration: TouchAnimationButton.transformAnimationTime, animations: {
        guard let view = weakSelf, let initialTransform = view.initialTransform else {
            return
        }
        view.layer.setAffineTransform(initialTransform)
    }, completion: { finished in
        weakSelf?.contentScaleFactor = UIScreen.main.scale
    })
}

override func touchesCancelled(_ touches: Set<UITouch>, with event: UIEvent?) {
    super.touchesCancelled(touches, with: event)
    weak var weakSelf = self
    UIView.animate(withDuration: TouchAnimationButton.transformAnimationTime, animations: {
        guard let view = weakSelf, let initialTransform = view.initialTransform else {
            return
        }
        view.layer.setAffineTransform(initialTransform)
    }, completion: { finished in
        weakSelf?.contentScaleFactor = UIScreen.main.scale
    })
}
}

Answer 1

这里我在我的baseView上添加了一个CAShapeLayer:

//My Bezier path
let combined = UIBezierPath()

//Create A layer instance        
let maskLayer = CAShapeLayer()

//Setting Bounds 
maskLayer.frame = baseView.bounds

//Assign a Name to layer that you will add
//This is important as if you want to remove a layer added by you 
maskLayer.name = "tailView"

//Assigned my path
maskLayer.path = combined.cgPath

调用此函数删除CAShapeLayer

func removeLayerFromView(baseView: UIView)
    {
        if let layer = baseView.layer.mask?.name
        {
            //Check Layer name 
            if layer == "tailView"
            { 
                //if yes Remove it 
                baseView.layer.mask?.removeFromSuperlayer()
            }
            else
            {
                //Layer not found
                print("Layer not found")
            }

        }
    }

在 UIView 中删除图层的行

//self.secondMainView name of View from which layer to be Removed
self.removeLayerFromView(baseView: self.secondMainView)

当您对 View 进行子类化时，如果 View 未更新，请调用 SetNeedsDisplay