Initialize a CGImage?

Question

人们一直说我需要将cameraView2初始化为CGImage。我对Swift语法还很陌生，有人能帮忙吗？

注意：cameraView是cameraView2的UIImageView，它应该是CGImage转换(如果有意义的话(。

class ViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate {

@IBOutlet weak var cameraButton: UIButton!
@IBOutlet weak var cameraView: UIImageView!
@IBOutlet weak var photosButton: UIButton!
@IBOutlet weak var crosshair: UIImageView!
///var cameraView2 = CGImage(named: "cameraView")
//init(cameraView: CGImage)
//var crosshair2: CGPoint!
//var cameraView2: CGImage!
//var cameraView2 = CGImage(UIImageView: cameraView)

///评论是不起作用的。CGImagecameraView2应该通过一个函数：

guard let CGImage = cameraView2, let provider = CGImage.dataProvider else {
return nil
}

我期待着你们的来信。谢谢

Answer 1

将图像视图的图像转换为CGImage:

cameraView.image?.cgImage

但是，如果在注释行旁边将其分配给cameraView2，它将不起作用。您需要在将图像放入cameraView之后进行分配。你应该知道那是什么时候。

// declare this alongside the IBOutlets
var cameraView2: CGImage?
...
// assign cameraView.image?.cgImage when cameraView actually has an image
cameraView2 = cameraView.image?.cgImage