使用 UIPencilKit 预定义的形状

Question

我正在使用 UIPencilKit 创建一个绘图应用程序，我还需要通过从列表中选择一个形状并自动在画布上绘制一些预定义的形状，如直线、圆形、矩形、箭头等。 任何帮助如何实现它？ 提前致谢

Answer 1

您可以像这样修改 PKDrawing 的 strokes 数组：

class ViewController: UIViewController {

    @IBOutlet weak var canvasView: PKCanvasView!
    
    override func viewDidLoad() {
        super.viewDidLoad()
        
        drawLine(point1: CGPoint(x: 0, y: 0), point2: CGPoint(x: 1000, y: 1000), color: .red, size: CGSize(width: 10, height: 10))
    }
    
    func drawLine(point1: CGPoint, point2: CGPoint, color: UIColor, size: CGSize) {
        // Define soints on strokePath
        let strokePoint1 = PKStrokePoint(location: point1, timeOffset: TimeInterval.init(), size: size, opacity: 2, force: 2, azimuth: 2, altitude: 1)
        let strokePoint2 = PKStrokePoint(location: point2, timeOffset: TimeInterval.init(), size: size, opacity: 2, force: 2, azimuth: 2, altitude: 1)
        
        // Define strokePath
        let strokePath = PKStrokePath(controlPoints: [strokePoint1, strokePoint2], creationDate: Date())
        
        // Define stroke
        let stroke = PKStroke(ink: PKInk(.pen, color: .red), path: strokePath)
        
        // Append stroke to strokes array in drawing
        canvasView.drawing.strokes.append(stroke)
    }
}