身份认证（动画、摄像头）

前言

休了半年产假，回来发现快要不会写代码了。慢慢琢磨了一小段代码仅供自己参考

效果.gif

思考

首先想需要再当前的view中间抠掉一个圆实现局部透明的遮罩效果。而 CAShapeLayer 的 fillRule属性可以帮我们实现这个过程。奇偶填充规则（Even Odd Fill Rule）指的是：在绘制 UIBezierPath 的过程中，会碰到同一个点被覆盖多次的情况。当一个点被覆盖偶数（0 属于偶数）次的时候，表示其位于图像外，而奇数次则表示位于图形内。位于图形内的点会被填充颜色，位于图形外的则不会。总结就是奇数填充，偶数不填充
那么：

let roundRect = CGRect(x: (ScreenWidth - 235) / 2.0, y: 100, width: 235, height: 235)
// 绘制第一个矩形path为当前view的视图
let path = UIBezierPath(rect: UIScreen.main.bounds)
// 绘制第二个圆形path为摄像头大小
let bezierPath = UIBezierPath(roundedRect: roundRect, cornerRadius: 235 / 2)
path.append(bezierPath)
let shaperLayer = CAShapeLayer()
// 奇数填充，偶数不填充
shaperLayer.fillRule = .evenOdd
shaperLayer.fillColor = UIColor.white.cgColor
shaperLayer.path = path.cgPath
view.layer.addSublayer(shaperLayer)
// 为方便看出效果，可以把当前的view视图设置一个颜色
view.backgroundColor = UIColor.lightGray

运行之后可以看到如下效果：

奇偶填充规则.gif

添加外圈动画

首先把图片添加上去

let outImageView = UIImageView()
outImageView.image = UIImage(named: "face_animation_0")
view.addSubview(outImageView)
let imgCenterY = roundRect.origin.y + roundRect.height / 2.0
outImageView.snp.makeConstraints { (make) in
    make.centerX.equalToSuperview()
    make.centerY.equalTo(imgCenterY)
    make.size.equalTo(CGSize(width: 280, height: 280))
}
        
let inImageView = UIImageView()
inImageView.image = UIImage(named: "face_animation_1")
view.addSubview(inImageView)
inImageView.snp.makeConstraints { (make) in
     make.centerX.equalToSuperview()
     make.centerY.equalTo(imgCenterY)
     make.size.equalTo(CGSize(width: 270, height: 270))
}

图片.png

给图片添加动画

let roationAnimation = CABasicAnimation(keyPath: "transform.rotation.z")
roationAnimation.fromValue = 0
roationAnimation.toValue = Double.pi * 2
roationAnimation.repeatCount = MAXFLOAT
roationAnimation.speed = 1
roationAnimation.duration = 3
roationAnimation.isRemovedOnCompletion = false
outImageView.layer.add(roationAnimation, forKey: nil)

let roationAnimation1 = CABasicAnimation(keyPath: "transform.rotation.z")
roationAnimation1.fromValue = 0
roationAnimation1.toValue = -Double.pi * 2
roationAnimation1.repeatCount = MAXFLOAT
roationAnimation1.speed = 1
roationAnimation1.duration = 3
roationAnimation1.isRemovedOnCompletion = false
inImageView.layer.add(roationAnimation1, forKey: nil)

动画.gif

打开前置摄像头

//音频视频相关类，记得在info.plist文件配置NSCameraUsageDescription
private var device: AVCaptureDevice!
private var videoPrelayer: AVCaptureVideoPreviewLayer!
private var input: AVCaptureDeviceInput!
private var output: AVCaptureStillImageOutput!
private var session: AVCaptureSession!

      //获取后置摄像头设备对象
      for item in AVCaptureDevice.devices(for: .video) {
                  if item.position == .front {
                      device = item
                  }
              }
      // 创建媒体管理会话
        session = AVCaptureSession()
       // 创建输入数据对象
        input = try? AVCaptureDeviceInput.init(device: device)
        // 创建输出数据对象
        output = AVCaptureStillImageOutput()
        output.outputSettings = [AVVideoCodecKey: AVVideoCodecJPEG]
        //添加输入数据对象和输出对象到会话中
        if session.canAddInput(input) {
            session.addInput(input)
        }
        if session.canAddOutput(output) {
            session.addOutput(output)
        }
        // 创建视频预览图层
        videoPrelayer = AVCaptureVideoPreviewLayer.init(session: session)
        videoPrelayer.videoGravity = .resizeAspectFill
        videoPrelayer.frame = roundRect
        // 插入图层在view视图的最下方
        view.layer.insertSublayer(videoPrelayer, at: 0)
        session.startRunning()

运行，效果就出来了。