可视化水龙头视图，显示水龙头指示器

Question

我想添加水龙头，以专注于我的自定义相机视图，我设法做到这一点，但现在我需要显示的东西，使用户可以知道他实际上在做一些事情。 ......展示一个像苹果黄色广场或SnapChat白色圆圈的用户界面。自定义指标...

这里是我的代码：

override func touchesBegan(_ touches: Set<UITouch>, with event: UIEvent?) { 
     let screenSize = view.bounds.size 
     if let touchPoint = touches.first { 
      let x = touchPoint.location(in: view).y/screenSize.height 
      let y = 1.0 - touchPoint.location(in: view).x/screenSize.width 
      let focusPoint = CGPoint(x: x, y: y) 

      if let device = captureDevice { 
       do { 
        try device.lockForConfiguration() 

        device.focusPointOfInterest = focusPoint 
        //device.focusMode = .continuousAutoFocus 
        device.focusMode = .autoFocus 
        //device.focusMode = .locked 
        device.exposurePointOfInterest = focusPoint 
        device.exposureMode = AVCaptureExposureMode.continuousAutoExposure 
        device.unlockForConfiguration() 
       } 
       catch { 
        // just ignore 
       } 
      } 
     } 
    } 

现在，我怎么添加自定义指标上触摸对焦？谢谢

Answer 1

在屏幕的其余部分顶部添加覆盖视图。然后你可以在draw（）函数中绘制你的指标。每当你需要覆盖显示来更新时调用它的setNeedsDisplay（）函数。在下面的例子中，我已经在设置函数中包含了touchPoint。确保在此视图上禁用用户交互，否则您的触摸将无法通过底层用户界面。

class OverlayView : UIView { 

    override func draw(_ rect: CGRect) { 
     // draw your touch indicator here 
     if let pt = _touchPoint { 
      let color:UIColor = UIColor.gray 
      let rect = CGRect(x:pt.x - 30, y:pt.y - 30, width:60, height:60) 
      let bpath:UIBezierPath = UIBezierPath(rect: rect) 

      color.set() 
      bpath.stroke() 
     } 
    } 

    private var _touchPoint : CGPoint? 
    var touchPoint : CGPoint? { 
     set(value) { 
      _touchPoint = value 
      setNeedsDisplay() 
     } 
     get { 
      return _touchPoint 
     } 
    } 

}