Core Graphics不会绘制某些行

Question

概述：
我试图在UILabel（作为背景）的顶部绘制一个简笔画，并且“头部”完美地绘制。然而，尽管改变了“脊椎”以模仿头部的绘图程序并改变UILabel背景（以排除颜色问题），但没有出现任何其他内容。

上下文回溯列出CGContextSaveGState, CGContextSetLineWidth, CGContextSetLineJoin, CGContextSetLineCap, CGContextSetMiterLimit, CGContextSetFlatness, CGContextAddPath, CGContextDrawPath, CGContextRestoreGState, CGContextSetLineWidth有问题，每次都不止一次，但没有发生错误。

TLDR：除了头部之外的一切都没有画出来，我不知道为什么......

代码：

import UIKit
import CoreGraphics
import Foundation

let π:CGFloat = CGFloat(M_PI)

class generateViewController: UIViewController, UIPickerViewDelegate, UIPickerViewDataSource {

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                         <OUTLETS & VARIABLES>                                          //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

@IBOutlet var          generateView: UIView!
@IBOutlet weak var      jointPicker: UIPickerView!
@IBOutlet weak var   verticalSlider: UISlider!
@IBOutlet weak var horizontalSlider: UISlider!
@IBOutlet weak var       saveButton: UIButton!
@IBOutlet weak var       undoButton: UIButton!
@IBOutlet weak var      printButton: UIButton!

var jointPickerData: [[String]] = [[String]]()

var   top: Float = 126
var   bot: Float = 574
var right: Float = 1198

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                         <VIEW DID LOAD>                                                //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

override func viewDidLoad() {

    super.viewDidLoad()
     self.jointPicker.delegate   = self
     self.jointPicker.dataSource = self
    jointPickerData = [["Neck","Shoulder","Elbow","Wrist","Spine","Hip","Knee","Ankle"],["Left","Right"]]

    draw(CGRect(x: 0,
                y: Int(top),
            width: Int(right),
           height: Int(top - bot)))

}

override func viewDidAppear(_ animated: Bool) {

    let value = UIInterfaceOrientation.landscapeLeft.rawValue
    UIDevice.current.setValue(value, forKey: "orientation")
    AppUtility.lockOrientation(.landscapeLeft, andRotateTo: .landscapeLeft)

}
override func viewWillDisappear(_ animated: Bool) {

    super.viewWillDisappear(animated)
    // Don't forget to reset when view is being removed
    AppUtility.lockOrientation(.all)

}

override func didReceiveMemoryWarning() {

    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.

}
  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                         <PICKER FUNCTIONS>                                             //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

//Number of columns
func numberOfComponents(in: UIPickerView) -> Int {
    return 2
}
//Number of rows
func pickerView(_ pickerView: UIPickerView, numberOfRowsInComponent component: Int) -> Int {
    return jointPickerData[component].count
}
//Data to return for the row and column being read
func pickerView(_ pickerView: UIPickerView, titleForRow row: Int, forComponent component: Int) -> String? {
    return jointPickerData[component][row]
}
//Catpure the picker view selection
func pickerView(_ pickerView: UIPickerView, didSelectRow row: Int, inComponent component: Int) {
    // This method is triggered whenever the user makes a change to the picker selection.
    // The parameter named row and component represents what was selected.
}

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                         <SLIDER FUNCTIONS>                                             //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

@IBAction func vertical(_ sender: Any){
    if jointPicker.selectedRow(inComponent: 1) == 0 {//left
        if jointPicker.selectedRow(inComponent: 0) == 0 {//lNeck
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 1 {//lShoulder
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 2 {//lElbow
            lElbowYGlobal.lElbowY = Int((verticalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 3 {//lWrist
            lWristYGlobal.rWristY = Int((verticalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 4 {//lSpine
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 5 {//lHip
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 6 {//lKnee
            lKneeYGlobal.lKneeY = Int((verticalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 7 {//lAnkle
            lAnkleYGlobal.lAnkleY = Int((verticalSlider.value - 0.5) * 200)

        }

    }
    if jointPicker.selectedRow(inComponent: 1) == 1 {//right
        if jointPicker.selectedRow(inComponent: 0) == 0 {//rNeck
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 1 {//rShoulder
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 2 {//rElbow
            rElbowYGlobal.rElbowY = Int((verticalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 3 {//rWrist
            rWristYGlobal.rWristY = Int((verticalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 4 {//rSpine
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 5 {//rHip
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 6 {//rKnee
            rKneeYGlobal.rKneeY = Int((verticalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 7 {//rAnkle
            rAnkleYGlobal.rAnkleY = Int((verticalSlider.value - 0.5) * 200)

        }

    }
    generateView.setNeedsDisplay()
    draw(CGRect(x: 0,
                y: Int(top),
            width: Int(right),
           height: Int(top - bot)))
}

@IBAction func horizontal(_ sender: Any) {
    if jointPicker.selectedRow(inComponent: 1) == 0 {//left
        if jointPicker.selectedRow(inComponent: 0) == 0 {//lNeck
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 1 {//lShoulder
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 2 {//lElbow
            lElbowXGlobal.lElbowX = Int((horizontalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 3 {//lWrist
            lWristXGlobal.lWristX = Int((horizontalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 4 {//lSpine
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 5 {//lHip
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 6 {//lKnee
            lKneeXGlobal.lKneeX = Int((horizontalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 7 {//lAnkle
            lAnkleXGlobal.lAnkleX = Int((horizontalSlider.value - 0.5) * 200)

        }

    }
    if jointPicker.selectedRow(inComponent: 1) == 1 {//right
        if jointPicker.selectedRow(inComponent: 0) == 0 {//rNeck
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 1 {//rShoulder
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 2 {//rElbow
            rElbowXGlobal.rElbowX = Int((horizontalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 3 {//rWrist
            rWristXGlobal.rWristX = Int((horizontalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 4 {//rSpine
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 5 {//rHip
            //nothing yet
        }
        if jointPicker.selectedRow(inComponent: 0) == 6 {//rKnee
            rKneeXGlobal.rKneeX = Int((horizontalSlider.value - 0.5) * 200)

        }
        if jointPicker.selectedRow(inComponent: 0) == 7 {//rAnkle
            rAnkleXGlobal.rAnkleX = Int((horizontalSlider.value - 0.5) * 200)

        }

    }
    generateView.setNeedsDisplay()
    draw(CGRect(x: 0,
                y: Int(top),
            width: Int(right),
           height: Int(top - bot)))
}

func draw(_ rect: CGRect) {

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                              <LINES>                                                   //
////////////////////////////////////////////////////////////////////////////////////////////////////////////
    /*
        aPath.move(to: CGPoint(x:300,
                               y:300 + Int(top)))

     aPath.addLine(to: CGPoint(x:200,
                               y:300 + Int(top)))

     aPath.lineWidth = 10.0

     aPath.close()

     //Apply black color
     UIColor.black.set()
     aPath.stroke()
     //Fill it as well
     //aPath.fill()
     */

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                               <HEAD>                                                   //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

    let circle = UIView(frame: CGRect(x: 560,
                                      y: 10.0 + Double(top),
                                  width: 100.0,
                                 height: 100.0))

    circle.center             = CGPoint(x: 560,
                                        y: 80 + Int(top))
    circle.layer.cornerRadius = 50
    circle.backgroundColor    = UIColor.black
    circle.clipsToBounds      = true

    let circle2 = UIView(frame: CGRect(x: 25.0,
                                       y: 25.0 + Double(top),
                                   width: 90.0,
                                  height: 90.0))

    circle2.center             = circle.center
    circle2.layer.cornerRadius = 45
    circle2.backgroundColor    = UIColor.white
    circle2.clipsToBounds      = true

    /*
     var darkBlur = UIBlurEffect(style: UIBlurEffectStyle.dark)
     var blurView = UIVisualEffectView(effect: darkBlur)

     blurView.frame = circle.bounds

     circle.addSubview(blurView)
 */
    generateView.addSubview(circle)
    generateView.addSubview(circle2)

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                               <SPINE>                                                  //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

    let spine = UIView(frame: CGRect(x: 560,
                                     y: 110 + Double(top),
                                 width: 10,
                                height: 110))
    func spineDraw(){
        spine.center             = CGPoint(x: 560,
                                           y: 165 + Int(top))
        spine.layer.cornerRadius = 5
        spine.backgroundColor    = UIColor.black
        spine.clipsToBounds      = true

        generateView.addSubview(spine)
    }

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                               <ARMS>                                                   //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

    var shoulder = CGPoint(x: 400,
                           y: 120 + Int(top))
    var rElbow = CGPoint(x: 410 + rElbowXGlobal.rElbowX,
                         y: 170 + rElbowYGlobal.rElbowY + Int(top))
    var rWrist = CGPoint(x: 410 + rWristXGlobal.rWristX,
                         y: 195 + rWristYGlobal.rWristY + Int(top))

    let rArm = UIBezierPath()
    rArm.lineWidth = 5

    func rArmDraw() {
        rArm.move(to: shoulder)
        rArm.addLine(to: rElbow)
        rArm.stroke()
        rArm.addLine(to: rWrist)
        rArm.stroke()
        rArm.close()
    }

    var lElbow = CGPoint(x: 390 + lElbowXGlobal.lElbowX,
                         y: 170 + lElbowYGlobal.lElbowY + Int(top))
    var lWrist = CGPoint(x: 390 + lWristXGlobal.lWristX,
                         y: 195 + lWristYGlobal.lWristY + Int(top))

    let lArm = UIBezierPath()
    lArm.lineWidth = 5

    func lArmDraw(){
        lArm.move(to: shoulder)
        lArm.addLine(to: lElbow)
        lArm.stroke()
        lArm.addLine(to: lWrist)
        lArm.stroke()
        lArm.close()
    }

  ////////////////////////////////////////////////////////////////////////////////////////////////////////////
 //                                               <LEGS>                                                   //
////////////////////////////////////////////////////////////////////////////////////////////////////////////

    var hip = CGPoint(x: 400,
                      y: 215 + Int(top))

    var rKnee  = CGPoint(x: 410 + rKneeXGlobal.rKneeX,
                         y: 250 + rKneeYGlobal.rKneeY   + Int(top))
    var rAnkle = CGPoint(x: 410 + rAnkleXGlobal.rAnkleX,
                         y: 270 + rAnkleYGlobal.rAnkleY + Int(top))

    let rLeg = UIBezierPath()
    rLeg.lineWidth = 5

    func rLegDraw(){
        rLeg.move(to: hip)
        rLeg.addLine(to: rKnee)
        rLeg.stroke()
        rLeg.addLine(to: rAnkle)
        rLeg.stroke()
        rLeg.close()
    }

    var lKnee  = CGPoint(x: 390 + lKneeXGlobal.lKneeX,
                         y: 250 + lKneeYGlobal.lKneeY   + Int(top))
    var lAnkle = CGPoint(x: 390 + lAnkleXGlobal.lAnkleX,
                         y: 270 + lAnkleYGlobal.lAnkleY + Int(top))

    let lLeg = UIBezierPath()
    lLeg.lineWidth = 5

    func lLegDraw(){
        lLeg.move(to: hip)
        lLeg.addLine(to: lKnee)
        lLeg.stroke()
        lLeg.addLine(to: lAnkle)
        lLeg.stroke()
        lLeg.close()
    }


    //debug grid
    let path = UIBezierPath()
    for i in 1...10 {
           path.move(to: CGPoint(x: i*100,
                                 y: 0     + Int(top)))
        path.addLine(to: CGPoint(x: i*100,
                                 y: 1000  + Int(top)))
        path.stroke()
           path.move(to: CGPoint(x: 0,
                                 y: i*100 + Int(top)))
        path.addLine(to: CGPoint(x: 2000,
                                 y: i*100 + Int(top)))
    }

//        spineDraw()
//        rArmDraw()
//        lArmDraw()
//        rLegDraw()
//        lLegDraw()
    generateView.setNeedsDisplay()
}

}

如有必要，我可以提供整个回溯。 （我现在懒得这么做）

提前致谢！

Answer 1

我最终解决了自己的问题：

1. 将绘图代码移动到自己的类
2. 创建文本框所在的UIView（在界面构建器中）
3. 将所述UIView的自定义类设置为新类

最重要的是：

1. 删除封装绘图代码的功能*

我不知道为什么功能会阻止绘图，我只知道它只是...

*示例：

let spine = UIView(frame: CGRect(x: 560,
                                 y: 110 + Double(top),
                             width: 10,
                            height: 110))
func spineDraw(){
    spine.center             = CGPoint(x: 560,
                                       y: 165 + Int(top))
    spine.layer.cornerRadius = 5
    spine.backgroundColor    = UIColor.black
    spine.clipsToBounds      = true

    generateView.addSubview(spine)
}

应该是：

let spine = UIView(frame: CGRect(x: 560,
                                 y: 110 + Double(top),
                             width: 10,
                            height: 110))

    spine.center             = CGPoint(x: 560,
                                       y: 165 + Int(top))
    spine.layer.cornerRadius = 5
    spine.backgroundColor    = UIColor.black
    spine.clipsToBounds      = true

    NewView.addSubview(spine)