joethemow joethemow - 1 month ago 9
iOS Question

CAShapeLayer not appearing on layer subview

I am drawing a line between two points, but nothing is appearing on the view. I have search other s/o questions but can't seem to find a solution.

override func viewDidLoad() {
super.viewDidLoad()
self.drawLineFromPoint(point1: CGPoint(x: 10,y: 50), point2: CGPoint(x: 10,y: 80))
}


func drawLineFromPoint(point1:CGPoint, point2:CGPoint) {

let path = UIBezierPath()
path.move(to: point1)
path.addLine(to: point2)

let shapeLayer = CAShapeLayer()
shapeLayer.bounds = CGRect(x: 100, y: 100, width: 100, height: 100)

shapeLayer.path = path.cgPath
shapeLayer.strokeColor = UIColor.green.cgColor
shapeLayer.lineWidth = 3
shapeLayer.fillColor = UIColor.clear.cgColor
self.view.layer.addSublayer(shapeLayer)
}

Joe Joe
Answer

Try this code: tested in Swift 3.

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.

    let shapeLayer = ShapeView(frame: CGRect(x: 100, y: 200, width: 100, height: 100), shape: 0)
    shapeLayer.backgroundColor = UIColor.clear
    shapeLayer.layer.borderWidth = 5
    shapeLayer.layer.borderColor = UIColor.red.cgColor
    view.addSubview(shapeLayer)
}

Create a swift file and name it ShapeView.swift in UIView class and add the following code.

import UIKit

class ShapeView: UIView {
var currentShapeType: Int = 0

init(frame: CGRect, shape: Int) {
    super.init(frame: frame)
    self.currentShapeType = shape
}
required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

 override func draw(_ rect: CGRect) {

    let ctx = UIGraphicsGetCurrentContext()
    ctx?.beginPath()
    ctx?.move(to: CGPoint(x: 10.0, y: 50.0))
    ctx?.addLine(to: CGPoint(x: 10.0, y: 80.0))
   // ctx?.addLine(to: CGPoint(x: 100.0, y: 200.0))
    ctx?.setLineWidth(3)
    ctx?.closePath()
    ctx?.strokePath()     
}   
}

Output:

enter image description here