如何在Swift 5 Playground中绘制文本，形状，线条

如何解决如何在Swift 5 Playground中绘制文本，形状，线条

我正试图在操场上以5速画一张井字棋。

我在左上方的方框中画圆时遇到问题。 addArc函数绘制半径加上圆（我不确定为什么吗？）。我宁愿使用具有适当字体属性的text（“ O”，“ X”）为文本着色和调整大小，但我也想知道如何绘制没有半径的圆。

这在操场上有可能吗？有人可以帮忙吗？

示例代码：

import UIKit
import PlaygroundSupport

public class SimpleLine: UIView  {
    
    public init() {
        super.init( frame: CGRect( x: 0,y: 0,width: 320,height: 480 ) )
        backgroundColor = .darkGray
    }
    
    public required init?( coder aDecoder: NSCoder ) {
        fatalError("init(coder:) has not been implemented")
    }
    
    public override func draw( _ rect: CGRect ) {
        guard let context = UIGraphicsGetCurrentContext() else {return}
        
        context.setlinewidth( 4.0 )
        context.setstrokeColor( UIColor.red.cgColor )
        
        // draw right perpendicular line
        context.move( to: CGPoint( x: 110,y: 100 ) )
        context.addLine( to: CGPoint( x: 110,y: 355 ) )
        
        // draw left perpendicular line
        context.move( to: CGPoint( x: 210,y: 100 ) )
        context.addLine( to: CGPoint( x: 210,y: 355 ) )
        
        // draw the first horizontal line
        context.move( to: CGPoint( x: 20,y: 180 ) )
        context.addLine( to: CGPoint( x: 300,y: 180 ) )
        
        // draw the second horizontal line
        context.move( to: CGPoint( x: 20,y: 270 ) )
        context.addLine( to: CGPoint( x: 300,y: 270 ) )
        
        // draw the tictac board
        context.strokePath()
        
        context.setlinewidth( 2.0 )
        context.setstrokeColor( UIColor.white.cgColor )
        
        // draw first part of the X
        context.move( to: CGPoint( x: 130,y: 199 ) )
        context.addLine( to: CGPoint( x: 190,y: 250 ) )
        
        // draw second part of the X
        context.move( to: CGPoint( x: 190,y: 199 ) )
        context.addLine( to: CGPoint( x: 130,y: 250 ) )
        
        // draw circle
        context.move( to: CGPoint( x: 62,y: 138 ) )
        context.addArc( center: CGPoint( x: 62,y: 138 ),radius: 26.00,startAngle: 0,endAngle: 90,clockwise: false )
        
        context.strokePath()
    }
}

PlaygroundPage.current.liveView = SimpleLine()