swift - 如何在 UIView Swift 3 中包含负坐标

Question

我的问题类似于以下问题:

Negative coordinates in UIView.frame

iOS使用UIKit绘图时，默认原点位于左上角；为什么？

我需要原点位于框架的中心；我想要绘制的坐标包含负数

我一直在搜索，但找不到如何使用 UIKit 在 Swift 3 中绘制数据点

这是我目前拥有的:

import Foundation
import UIKit

@IBDesignable
public class Contours: UIView {

    public var gridColor: UIColor = UIColor.clear
    public var gridSize: CGSize = CGSize(width: 100, height: 100)
    public var gridView = UIView(frame: CGRect(origin: .zero, size: .zero))

    public var dataSize: CGSize = CGSize(width: 5, height: 5)
    public var dataColor: UIColor = UIColor.blue
    public var dataLineColor: UIColor = UIColor.red
    public var dataBorderWidth: CGFloat = 1.0
    public var dataView = UIView(frame: CGRect(origin: .zero, size: .zero))

    public var fade: CGFloat = 0.5

    public var distances: [Int] = [2601, 2600, 33, 2608, 2601, 2594, 2625, 2633, 2637, 2651, 2656, 2666, 2683, 2690, 2705, 2712, 2712, 2739, 2752, 53, 1103, 1060, 1019, 980, 944, 911, 33, 851, 826, 801, 777, 757, 737, 718, 701, 683, 667, 654, 53, 486, 470, 457, 448, 440, 432, 424, 416, 409, 403, 396, 389, 383, 378, 372, 367, 362, 357, 353, 348, 344, 340, 336, 333, 329, 326, 323, 319, 317, 314, 311, 309, 307, 305, 303, 301, 299, 298, 297, 295, 294, 293, 292, 291, 290, 290, 290, 290, 291, 293, 295, 303, 386, 383, 53, 350, 53, 53, 53, 53, 53, 3, 364, 362, 360, 356, 358, 355, 353, 351, 350, 349, 347, 345, 53, 53, 53, 308, 3, 309, 309, 312, 313, 315, 316, 319, 321, 53, 329, 332, 335, 332, 53, 53, 53, 53, 53, 53, 53, 3, 53, 53, 53, 53, 53, 53, 670, 33, 706, 728, 750, 772, 799, 825, 856, 887, 925, 755, 749, 744, 739, 734, 730, 727, 722, 719, 716, 714, 634, 709, 706, 704, 703, 701, 699, 700, 695, 697, 697, 338, 696, 697, 696, 698, 698, 700, 702, 703, 705, 707, 710, 712, 714, 718, 53, 53, 53, 53, 53, 53, 53, 53, 3, 53, 53, 53, 53, 53, 53, 53, 53, 3, 53, 53, 53, 53, 53, 53, 53, 3412, 3397, 3384, 53, 3538, 3603, 53, 2426, 2412, 2363, 2330, 2288, 2262, 2214, 2190, 2162, 2130, 53, 53, 53, 2807, 2631, 2408, 2638, 2607, 2601, 2562, 2534, 2515, 2496, 2478, 2462, 2445, 53, 53, 53, 1751, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 53, 3, 53, 53, 53, 53, 53, 2643, 2643, 53, 2660, 53, 2528, 2523, 2221, 1955, 1684, 1677, 1684, 1694, 1705, 1202, 1204, 1211, 1217, 1225, 1233, 1239, 1249, 1259, 1270, 1280, 1289, 1280, 1011, 991, 977, 968, 966, 964, 968, 975, 984, 1003, 2, 53, 1297, 53, 53, 33, 1321, 1299, 1274, 1254, 1233, 1232, 1264, 1293, 3802, 53, 53, 53, 53, 53, 53, 53, 3, 53, 2878, 2870, 2848, 2821, 2803, 2788, 2769, 2753, 2740, 2708, 2711, 2701, 2682, 2656, 2664, 2644, 2644, 2631, 2626, 2616, 2610, 2604, 2605, 2605, 2600, 2598, 2603]

    public var distx: [Double] = []
    public var disty: [Double] = []
    public var scalex: [Double] = []
    public var scaley: [Double] = []

    override public init(frame: CGRect) {
        super.init(frame: frame)
    }

    public required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
    }

    public override func draw(_ rect: CGRect) {

        alpha = 1
        layer.backgroundColor = gridColor.cgColor
        clipsToBounds = false

        for index in 0...356 {
            let radians = Double(index) * M_PI / 180.0
            let x = Double(distances[index]) * cos(Double(radians))
            let y = Double(distances[index]) * sin(Double(radians))
            distx.append(x)
            disty.append(y)
        }

        let xmin: Double = Double(distx.min()!)
        let xmax: Double = Double(distx.max()!)
        let ymin: Double = Double(disty.min()!)
        let ymax: Double = Double(disty.max()!)

        let scale = max(xmax - xmin, ymax - ymin)

        var circles = [UIView]()
        circles.reserveCapacity(360)
        for _ in 0...356 {
            circles.append(UIView(frame: CGRect(origin: .zero, size: .zero)))
        }

        print("width: \(bounds.width), height: \(bounds.height)")

        for index in 0...356 {
            let radians = Double(index) * M_PI / 180.0
            let x = (Double(distances[index]) * cos(Double(radians)) / scale) * Double(325)
            let y = (Double(distances[index]) * sin(Double(radians)) / scale) * Double(325)

            var aPath = UIBezierPath()
            aPath.move(to: CGPoint(x: 0, y: 0))
            aPath.addLine(to: CGPoint(x: x, y: y))
            UIColor.cyan.set()
            aPath.stroke()
            aPath.fill()
            aPath.close()

            circles[index].alpha = 1
            circles[index].frame = CGRect(origin: .zero, size: dataSize)
            circles[index].center = CGPoint(x: x, y: -y)
            circles[index].layer.backgroundColor = dataColor.cgColor
            circles[index].layer.borderColor = dataLineColor.cgColor
            circles[index].layer.borderWidth = dataBorderWidth
            circles[index].layer.cornerRadius = circles[index].bounds.width / 2

            if let superview = circles[index].superview {
                superview.bringSubview(toFront: circles[index])
            } else {
                addSubview(circles[index])
            }

            scalex.append(x)
            scaley.append(y)
        }

        dataView.frame = CGRect(origin: .zero, size: dataSize)
        dataView.center = CGPoint(x: bounds.width / 2, y: bounds.height / 2)
        dataView.layer.backgroundColor = UIColor.cyan.cgColor
    }

    private func reset() {
        UIView.animate(withDuration: 0.25) { () -> Void in
            self.gridView.center = CGPoint(x: self.bounds.width / 2, y: self.bounds.height / 2)
        }
    }

}






class ViewController: UIViewController {

    @IBOutlet private weak var joystickMove: Joystick!
    @IBOutlet private weak var joystickRotate: Joystick!
    @IBOutlet private weak var objectView: UIView!

    override func viewDidLoad() {
        super.viewDidLoad()
        createJoystick()
        createContours()

//        joystickMove.trackingHandler = { (joystickData) -> () in
//            //print("joystickMove data: \(joystickData)")
//            
//            let scale: CGFloat = 5.0
//            
//            self.objectView.center.x += joystickData.velocity.x * scale
//            self.objectView.center.y += joystickData.velocity.y * scale
//        }
//        
//        joystickRotate.trackingHandler = { (joystickData) -> () in
//            //print("joystickRotate data: \(joystickData)")
//            
//            self.objectView.transform = CGAffineTransform(rotationAngle: joystickData.angle)
//        }
    }

    private func createJoystick() {
        // 1. Initialize an instance of `Joystick` using the constructor:
        let joystick = Joystick()

        let width: CGFloat = 100
        let hieght: CGFloat = 100
        let x_center = CGFloat(UIScreen.main.bounds.width/2) - CGFloat(width/2)
        let y_center = UIScreen.main.bounds.height - UIScreen.main.bounds.height/4

        joystick.frame = CGRect(x: x_center, y: y_center, width: width, height: hieght)
        joystick.backgroundColor =  UIColor.clear

        // 2. Customize the joystick.
        joystick.substrateColor = UIColor.lightGray
        joystick.substrateBorderColor = UIColor.gray
        joystick.substrateBorderWidth = 1.0
        joystick.stickSize = CGSize(width: 50, height: 50)
        joystick.stickColor = UIColor.darkGray
        joystick.stickBorderColor = UIColor.black
        joystick.stickBorderWidth = 2.0
        joystick.fade = 0.5

        // 3. Setup the tracking handler to get velocity and angle data:
//        joystick.trackingHandler = { (joystickData) -> () in
//            self.objectView.center.x += joystickData.velocity.x
//            self.objectView.center.y += joystickData.velocity.y
//        }

        // 4. Add the joystick to your view:
        view.addSubview(joystick)
    }

    private func createContours() {
        let contour = Contours(frame: CGRect(x: 90.0, y: 175.0, width: 250.0, height: 250.0))
        view.addSubview(contour)
    }

    @IBAction func resetButtonTapped(sender: AnyObject) {
        UIView.animate(withDuration: 0.5) { () -> Void in
            self.objectView.center = self.view.center
//            self.objectView.transform = CGAffineTransformIdentity
        }
    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

}

注意我的圆和线的位移:

以前是这样的:

Answer 1

最简单的方法是使用 CGAffineTransform。

这是一个很好的博客，解释了它们:http://iphonedevelopment.blogspot.ca/2008/10/demystifying-cgaffinetransform.html

但是，看起来您所需要的只是翻译。

因此创建您的转换:

let t = CGAffineTransform(translationX: bounds.width/2, y: bounds.height/2)

然后你想要的新坐标集上的每个点

let newPoint = oldPoint.applying(t)

您还可以使用它们来缩放值以适合您的屏幕。这是我用来绘制一些图表的仿射变换作为示例:

let chartTransform = CGAffineTransform(a: innerWidth/xMax, b: 0, c: 0, d: -innerHeight/yMax, tx: origin.x, ty: origin.y + innerHeight)

A 和 D 分别缩放 X 和 Y。因此，我按 View 宽度/最大 X 值的比率缩放 x 值，并按相同比例缩放 y 值。但因为 Y 随着你的下降而增加，所以我用负数翻转了比例。这会将正 y 轴置于垂直方向。为了对此进行调整，我必须将每个值向下平移图表的长度。 origin.x 和 origin.y 只是我开始绘制轴的小缩进。