ios笑脸app实现

import UIKit

@IBDesignable

class FaceView: UIView {

    @IBInspectable

    var lineWidth:CGFloat=3{didSet{setNeedsLayout()}}

    @IBInspectable

    var color:UIColor = UIColor.blueColor(){didSet{setNeedsLayout()}}

    @IBInspectable

    var scale:CGFloat=0.9{didSet{setNeedsLayout()}}

    var faceCenter:CGPoint{

        return convertPoint(center, fromView: superview)

    }

    var faceRadius:CGFloat{

         return min(bounds.size.width, bounds.size.height)/2*scale

    }

    private struct Scaling {

        static let FaceRadiusToEyeRadiusRatio: CGFloat = 10

        //大圆半径(face半径)与小圆半径(eye半径)的比率,次数越小,小圆越大.因为 下面bezierPathForEye的方法中定义 eyeRadius = faceRadius / Scaling.FaceRadiusToEyeRadiusRatio

        static let FaceRadiusToEyeOffsetRatio: CGFloat = 3

        //大圆与小圆的偏移率,此数越大,小圆的圆心距大圆越近

        static let FaceRadiusToEyeSeparationRatio: CGFloat = 1.5

        //两个小圆之间在大圆内的分离比率

        static let FaceRadiusToEyeMounthWidthRatio: CGFloat = 1

        static let FaceRadiusToEyeMounthHeightRatio: CGFloat = 3

        static let FaceRadiusToEyeMounthOffsetRatio: CGFloat = 3

    }

    private enum Eye {

        case Left , Right

    }

    private func bezierPathForEye(whichEye: Eye) -> UIBezierPath {

        //此处定义的方法为设置一只眼睛的位置,上面定义了左右眼的枚举,可通过调用.Left.Right来实现两个位置的设定

        let eyeRadius = faceRadius / Scaling.FaceRadiusToEyeRadiusRatio

        //定义小圆半径是大圆半径的几分之几,此处因为FaceRadiusToEyeRadiusRatio: CGFloat = 10 故为十分之一

        let eyeVerticalOffset = faceRadius / Scaling.FaceRadiusToEyeOffsetRatio

        //小圆的垂直偏距

        let eyeHorizontalSeparation = faceRadius / Scaling.FaceRadiusToEyeSeparationRatio

        //小圆的水平距离

        var eyeCenter = faceCenter

        eyeCenter.y -= eyeVerticalOffset

        //此处相当于是用大圆圆心的y坐标减去小圆圆心的y坐标,故小圆圆心在大圆圆心之上.若为加,则在下

        switch whichEye {

        case .Left: eyeCenter.x -= eyeHorizontalSeparation / 2

        //相当于大圆圆心的x坐标减去(小圆圆心的x坐标除以2),即在大圆圆心的左侧

        case .Right: eyeCenter.x += eyeHorizontalSeparation / 2

            //此处加,即在右侧

        }

        let path = UIBezierPath(arcCenter: eyeCenter, radius: eyeRadius, startAngle: 0, endAngle: CGFloat(2*M_PI), clockwise: true) //画圆

        path.lineWidth = lineWidth //设定线宽

        return path

    }

    private func bezierPathForSmile(fractionOfMaxSmile: Double) -> UIBezierPath {

        let mouthWidth = faceRadius / Scaling.FaceRadiusToEyeMounthWidthRatio

        //大圆半径与线宽的比率,此处线宽=大圆半径

        let mouthHeight = faceRadius / Scaling.FaceRadiusToEyeMounthHeightRatio

        //mouthHeight即线的中点到圆心的距离

        let mouthVerticalOffset = faceRadius / Scaling.FaceRadiusToEyeMounthOffsetRatio

        let smileHeight = CGFloat(max(min(fractionOfMaxSmile, 1), -1)) * mouthHeight

        //此处max(min(fractionOfMaxSmile, 1), -1)限定了笑脸指数只能在-1到1之间,fractionOfMaxSmile这个参数可以自行设定,如果设定的大于1,则只取1,设定小于-1,则只取-1

        let start = CGPoint(x: faceCenter.x - mouthWidth / 2, y: faceCenter.y + mouthVerticalOffset)  //设置起点

        let end = CGPoint(x: start.x + mouthWidth, y: start.y)  //设置终点

        let cp1 = CGPoint(x: start.x + mouthWidth / 3 , y: start.y + smileHeight) //设置曲线点1,此处mouthWidth / 3用于调节曲线的弧度

        let cp2 = CGPoint(x: end.x - mouthWidth / 3, y: cp1.y)  //设置曲线点2

        let path = UIBezierPath()

        path.moveToPoint(start)

        path.addCurveToPoint(end, controlPoint1: cp1, controlPoint2: cp2)

        path.lineWidth = lineWidth

        return path

    }

    override func drawRect(rect: CGRect) {

        let facePath=UIBezierPath(arcCenter: faceCenter, radius: faceRadius, startAngle: 0, endAngle: CGFloat(2*M_PI), clockwise: true)

        facePath.lineWidth=lineWidth

        color.set()

        facePath.stroke()

        bezierPathForEye(.Left).stroke()

        bezierPathForEye(.Right).stroke()

        let smiliness = 0.8

        let smilePath = bezierPathForSmile(smiliness)

        smilePath.stroke()

    }

}

• IBDesignable可以在storyboard中看到自定义的uiview
• IBInspectable使属性可以改变

利用协议与代理联结数据源

protocol FaceViewDataSource:class {

    func smilnessForFaceView(sender:FaceView)->Double?

}

手势识别实现缩放与改变笑脸弧度

 @IBOutlet weak var faceView: FaceView!{

        didSet{

            faceView.dataSource=self

            faceView.addGestureRecognizer(UIPinchGestureRecognizer(target: faceView, action: "scale:"))

            //faceView.addGestureRecognizer(UIPanGestureRecognizer(target: self, action: "changeHappiness:"))

        }

    }

    private struct Constants{

        static let HappinessGestureScale:CGFloat=4

    }

    @IBAction func changeHappiness(sender: UIPanGestureRecognizer) {

        switch sender.state {

        case .Ended:

            fallthrough

        case .Changed:

            let translation=sender.translationInView(faceView)

            let happinessChange = -Int(translation.y/Constants.HappinessGestureScale)

            if happinessChange != 0{

                happiness+=happinessChange

                sender.setTranslation(CGPoint.zero, inView: faceView)

            }

        default:

            break

        }

    }

    func scale(gesture:UIPinchGestureRecognizer){

        if gesture.state == .Changed{

            scale*=gesture.scale

            gesture.scale=1

        }

    }

源代码:Happiness