先列举一些已经不能使用的方法

废弃的方法.png

列举一下常用的方法

    //获取上下文对象
    let context = UIGraphicsGetCurrentContext()
    
    //线条颜色
    context?.setStrokeColor(UIColor.red.cgColor)
    
    //线条宽度
    context?.setLineWidth(1.0)
    
    //移动画笔到某一点
    context?.move(to: CGPoint(x: 10, y: 10))
    
    //画线
    context?.addLine(to: CGPoint(x: gameSize , y: 10))
    
    //画弧线
    context?.addArc(center: CGPoint.init(x: 150, y: 100), radius: 30, startAngle: 0, endAngle: CGFloat(M_PI*2), clockwise: true);
    
    //二次贝塞尔曲线
    context?.addQuadCurve(to: CGPoint.init(x: 150, y: 150), control: CGPoint.init(x: 50, y: 100))
    
    //三次贝塞尔曲线
    context?.addCurve(to: CGPoint.init(x: 250, y: 150), control1: CGPoint.init(x: 50, y: 100), control2: CGPoint.init(x: 100, y: 150))
    
    //绘制矩形
    context?.setFillColor(UIColor.brown.cgColor);
    //设置填充颜色
    context?.fill(CGRect.init(x: 50, y: 50, width: 100, height: 50));
    
    //绘制椭圆
    context?.strokeEllipse(in: CGRect.init(x: 50, y: 50, width: 100, height: 50));
    
    //绘制
    context?.strokePath()

再演示一个棋盘的DEMO

    //棋盘格数，可修改此参数定制棋盘大小
    let chessPiecesNumber = 10

    let gameViewSize = Double(frame.size.width - 20)
    
    let context = UIGraphicsGetCurrentContext()
    
    context?.setLineWidth(1.0)
    
    
    for i in 0..<chessPiecesNumber {
        
        context?.move(to: CGPoint(x: 10, y: 10 + gameViewSize / Double(chessPiecesNumber - 1) * Double(i)))
        context?.addLine(to: CGPoint(x: gameViewSize + 10, y: 10 + gameViewSize / Double(chessPiecesNumber - 1) * Double(i)))
        
        context?.strokePath()
    }

    for i in 0..<chessPiecesNumber {
        
        context?.move(to: CGPoint(x: 10 + gameViewSize / Double(chessPiecesNumber - 1) * Double(i), y: 10))
        context?.addLine(to: CGPoint(x: 10 + gameViewSize / Double(chessPiecesNumber - 1) * Double(i), y: gameViewSize + 10))
        
        context?.strokePath()
    }

注意：
1.for循环的 ...10 已经不能用了，必须用 ..<10 了
2.CGRect(x: 0, y: 0, width: 100, height: 100)已经不能改用了，必须用
CGRect(origin: CGPoint(x: 0, y: 0), size: CGSize(width: 100, height: 100))

棋盘.png