在三角形CAShapeLayer上方添加文本

// 创建CAShapeLayer对象并设置形状为三角形
let shapeLayer = CAShapeLayer()
let path = UIBezierPath()
path.move(to: CGPoint(x: 0, y: 0))
path.addLine(to: CGPoint(x: 50, y: 100))
path.addLine(to: CGPoint(x: 100, y: 0))
path.close()
shapeLayer.path = path.cgPath
shapeLayer.fillColor = UIColor.red.cgColor

// 创建CATextLayer对象并设置文本属性
let textLayer = CATextLayer()
textLayer.string = "Hello, World!"
textLayer.font = UIFont.systemFont(ofSize: 12)
textLayer.fontSize = 12
textLayer.foregroundColor = UIColor.black.cgColor
textLayer.alignmentMode = .center
textLayer.frame = CGRect(x: 25, y: -20, width: 50, height: 20)

// 添加CATextLayer对象到CAShapeLayer对象的父视图的图层中
view.layer.addSublayer(shapeLayer)
view.layer.addSublayer(textLayer)