在UIBezierPath上绘制放射状背景

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建一个UIBezierPath对象
        let path = UIBezierPath()
        
        // 设置起始点
        let center = view.center
        let radius: CGFloat = 100.0
        let startAngle: CGFloat = 0.0
        let endAngle: CGFloat = CGFloat(Double.pi * 2)
        path.move(to: CGPoint(x: center.x + radius, y: center.y))
        
        // 添加弧线
        path.addArc(withCenter: center, radius: radius, startAngle: startAngle, endAngle: endAngle, clockwise: true)
        
        // 设置背景颜色
        let fillColor = UIColor.red
        fillColor.setFill()
        path.fill()
    }
}