IOS Swift3 基本图形绘制

import UIKit

class ViewController: UIViewController {

    override func viewDidLoad() {

        super.viewDidLoad()

        // Do any additional setup after loading the view, typically from a nib.

        

        //状态栏大小

        let statusbar_width =  UIApplication.shared.statusBarFrame.width

        let statusbar_height = UIApplication.shared.statusBarFrame.height

        

        //屏幕大小，包括状态栏

        //let screen_width = UIScreen.main.bounds.width

        let Screen_height = UIScreen.main.bounds.height

        

        let viewRect = CGRect(x: 0, y: statusbar_height, width: statusbar_width, height: Screen_height - statusbar_height )

        let view1 = MyView(frame: viewRect)

        self.view.addSubview(view1)

    }

    override func didReceiveMemoryWarning() {

        super.didReceiveMemoryWarning()

        // Dispose of any resources that can be recreated.

    }

}

class MyView: UIView {

    override init(frame: CGRect) {

        super.init(frame: frame)

        //把背景色设为透明

        self.backgroundColor = UIColor.green

    }

    

    required init?(coder aDecoder: NSCoder) {

        fatalError("init(coder:) has not been implemented")

    }

    

    override func draw(_ rect: CGRect) {

        //获取画笔上下文

        let context:CGContext =  UIGraphicsGetCurrentContext()!

        context.setAllowsAntialiasing(true) //抗锯齿设置

        

        //绘制点 或 实心圆

        context.fillEllipse( in: CGRect(x: 10, y: 10, width: 2, height: 2))

        context.fillEllipse( in: CGRect(x: 15, y: 10, width: 1, height: 1))

        context.fillEllipse( in: CGRect(x: 20, y: 10, width: 0.5, height: 0.5))

        

        //绘制直线

        context.setStrokeColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1 );//设置画笔颜色方法一

        context.setLineWidth(1);//线条宽度

        context.move(to: CGPoint(x: 10, y: 40))//开始点位置

        context.addLine(to: CGPoint(x: 100, y: 40))//结束点位置

        context.strokePath();

        

        //绘制虚线

        context.setLineWidth(1);

        let dashArray: [CGFloat] = [2, 6,4,2 ]

        context.setLineDash(phase: 1, lengths: dashArray )

        context.move(to: CGPoint(x: 120, y: 40))//开始点位置

        context.addLine(to: CGPoint(x: 180, y: 40))//结束点位置

        context.strokePath();

        

        context.setLineDash(phase: 1, lengths: [1,1] )//还原点类型

        context.move(to: CGPoint(x: 200, y: 40))//开始点位置

        context.addLine(to: CGPoint(x: 260, y: 40))//结束点位置

        context.strokePath();

        

        //绘制曲线

        context.setLineDash(phase: 0, lengths: [1,0] )//还原点类型

        

        context.move(to: CGPoint(x: 10, y: 80))//开始点位置

        context.addCurve(to: CGPoint(x: 150, y: 80), control1: CGPoint(x: 50, y: 90), control2: CGPoint(x: 90, y: 70))

        context.strokePath();

        

        context.move(to: CGPoint(x: 160, y: 80))//开始点位置

        context.addQuadCurve(to: CGPoint(x: 250, y: 80), control: CGPoint(x: 200, y: 65))

        context.strokePath();

        

        //画圆

        context.setLineWidth(0.5);//线条宽度

        context.setStrokeColor(red: 0.5, green: 0.5, blue: 0.5, alpha: 1);

        context.addEllipse(in: CGRect(x: 10, y: 120, width: 20, height: 20)); //画圆 x,y左上角坐标

        context.strokePath() //关闭路径

        

        //画圆弧，单位弧度，clockwise: 顺时针计算，弧度 = 角度 * π ／ 180 x,y中心点坐标

        context.setStrokeColor( UIColor.red.cgColor );//设置画笔颜色方法二

        context.addArc(center: CGPoint(x: 50, y: 130), radius: 10, startAngle: 0, endAngle: CGFloat(90 * Double.pi/180), clockwise: true )

        context.strokePath() //关闭路径

        context.addArc(center: CGPoint(x: 70, y: 130), radius: 10, startAngle: 0, endAngle: CGFloat(90 * Double.pi/180), clockwise: false )

        context.strokePath() //关闭路径

        

        //绘制矩形

        context.setStrokeColor( UIColor.gray.cgColor );

        context.addRect(CGRect(x: 100, y: 120, width: 30, height: 20 ))

        context.strokePath();

        

        //字符串 x,y左上角坐标

        let strTxt:String = "你好！"

        strTxt.draw(at: CGPoint(x: 10, y: 160), withAttributes: nil )

        

        let textAttributes: [String: AnyObject] = [

            NSForegroundColorAttributeName : UIColor.blue.cgColor,

            NSFontAttributeName : UIFont.systemFont(ofSize: 8 )

        ]

        strTxt.draw(at: CGPoint(x: 80, y: 160), withAttributes: textAttributes )

        

        //绘制图片

        let path = Bundle.main.path(forResource: "fj", ofType: "png")

        let srcImage = UIImage(contentsOfFile: path!)

        srcImage?.draw(at: CGPoint(x: 10, y: 200))

        srcImage?.draw(in: CGRect(x: 100, y: 200, width: 50, height: 50 ))

    }
}