在CAShape圖層周圍繪制矩形

我是 Swift 和 Core Animation 的新手。我想像這張圖片一樣在 CAShapeLayer 周圍創建矩形框，但我不知道。

詳細地說，我正在通過PocketSVG決議 SVG 影像并將其UIBezierPath轉換為CAShapeLayer，然后將這些層作為sublayer添加到UI Image View中。

這是我將Path轉換為CaShape Layer的代碼。

fileprivate func createLayer(path: SVGBezierPath) -> CAShapeLayer {
    let shapeLayer = CAShapeLayer()
    shapeLayer.path = path.cgPath
    if let any = path.svgAttributes["stroke"] {
        shapeLayer.strokeColor = (any as! CGColor)
    }
    
    if let any = path.svgAttributes["fill"] {
        shapeLayer.fillColor = (any as! CGColor)
    }
    return shapeLayer
}

下面是代碼，我將圖層添加到 UIImage 視圖（backgroundIV）

        for path in paths {
        path.apply(.init(scaleX: scale, y: scale))
        let layer = createLayer(path: path)
        layer.frame = self.backgroundIV.bounds
        self.backgroundIV.layer.addSublayer(layer)
    }

我還將TapGesture、RotateGesture、ScaleGesture 和 PanGesture 添加到 CA Shape Layers，以下是代碼。

    @objc func rotateLayer(_ sender: UIRotationGestureRecognizer) {
    selectedLayer?.setAffineTransform(CGAffineTransform(rotationAngle: sender.rotation))
}

@objc func selectLayer(_ sender: UITapGestureRecognizer) {
    let point = sender.location(in: self.backgroundIV)
    guard let layers = self.backgroundIV.layer.sublayers
    else { return }
    var hitLayers: [CAShapeLayer] = []
    
    selectedLayer?.lineWidth = CGFloat(0)
    
    for subLayer in layers {
        if let thisLayer = subLayer as? CAShapeLayer,
           let pth = thisLayer.path {
            let layerPoint: CGPoint = thisLayer.convert(point, from: self.backgroundIV.layer)
            if pth.contains(layerPoint) {
                hitLayers.append(thisLayer)
            }
        }
    }
    
    selectedLayer = hitLayers.last
    selectedLayer?.strokeColor = UIColor.red.cgColor
    selectedLayer?.lineWidth = CGFloat(3)
    selectedLayerRect = CGRect(origin: point, size: CGSize(width: 100, height: 100))
    showPopupMenu()
    
}

@objc func moveLayer(_ recognizer: UIPanGestureRecognizer) {
    let p = recognizer.location(in: self.backgroundIV)
    selectedLayer?.position = p
}

@objc func scaleLayer(_ sender: UIPinchGestureRecognizer) {
    selectedLayer?.transform = CATransform3DMakeScale(sender.scale, sender.scale, 1)
}

在SelectLayer方法的最后幾行中，我通過增加其筆觸寬度和顏色來突出顯示所選圖層。

selectedLayer?.strokeColor = UIColor.red.cgColor
selectedLayer?.lineWidth = CGFloat(3)

當我不選擇圖層時，我只是將它的lineWidth值設定為 0，這不是一個好習慣。

有沒有辦法像這張圖片一樣創建矩形框？

uj5u.com熱心網友回復：

試試這個..
我希望這對你有幫助......????

import UIKit
class ViewController : UIViewController {

let containerView: UIView = {
    let view = UIView()
    view.backgroundColor = .clear
    return view
}()

override func viewDidLoad() {
    super.viewDidLoad()
    
    containerView.frame = CGRect(x: view.frame.width/2 - 100, y: view.frame.height/2 - 100, width: 200, height: 200)
    view.addSubview(containerView)
    
    drawRectangle()
}

private func drawRectangle() {
    
    let path = UIBezierPath()
    path.move(to: CGPoint(x: 0, y: 0))
    path.addLine(to: CGPoint(x: 200, y: 0))
    path.addLine(to: CGPoint(x: 200, y: 200))
    path.addLine(to: CGPoint(x: 0, y: 200))
    path.addLine(to: CGPoint(x: 0, y: 0))
    
    let shapeLayer = CAShapeLayer()
    shapeLayer.path = path.cgPath
    shapeLayer.strokeColor = UIColor.red.cgColor
    shapeLayer.fillColor = UIColor.black.cgColor
    shapeLayer.lineWidth = 3
    
    containerView.layer.addSublayer(shapeLayer)
    }
}

uj5u.com熱心網友回復：

如果您想在圖層的框架周圍繪制一個框，那很容易。只需設定aLayer.borderWidth=1和aLayer.borderColor=UIColor.someColor.cgColor。

系統將為您在圖層周圍添加邊框。

但是，如果您的圖層的框架大于它們包含的矩形的路徑，則可能會比您想要的大。

標籤：ios 迅速 svg 核心动画 口袋svg

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