ios - Swift 3 拍照并保存

Question

在 Swift 3 中工作。我发现了很多有答案的问题，还有博客，但我尝试过的一切都没有奏效。我只是想捕捉我拍摄的相机照片并将其保存到文档中。但它没有被保存，因为当从 xcode 中查看时它没有显示在设备文档下，而且我没有收到任何错误或类似错误。我有点迷路了。

获取图片并保存的代码

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
    var pickedImage = UIImage()
    pickedImage = info[UIImagePickerControllerOriginalImage] as! UIImage
    picker.dismiss(animated: true, completion: nil)

    let currentDateTime = Date()
    let formatter = DateFormatter()
    formatter.dateFormat = "yyyyMMddHHmmss"
    let fileNameWithExtension = "ts_\(formatter.string(from: currentDateTime)).png"
    //create path
    let imagePath = fileInDocumentsDirectory(filename: fileNameWithExtension)
    imageStringPathSet = fileNameWithExtension
    imageSet = pickedImage

    if saveImage(image: pickedImage, path: imagePath) {
        cameraButton.setImage(#imageLiteral(resourceName: "ic_camerashot_yes60dp"), for: UIControlState.normal)
        return
    }
    cameraButton.setImage(#imageLiteral(resourceName: "ic_camerashot_no60dp"), for: UIControlState.normal)
}
func fileInDocumentsDirectory(filename: String)-> URL {
    return try! FileManager.default.url(for: .documentDirectory, in: .userDomainMask, appropriateFor: nil, create: false).appendingPathComponent(filename)
}
func saveImage(image: UIImage, path: URL) -> Bool {
    print(path)
    guard let pngImageData = UIImagePNGRepresentation(image) else {
        print("error")
        return false
    }

    var resultValid = false
    do {
        let results = try pngImageData.write(to: path, options: [.atomicWrite])
        print(results) //prints ()
        resultValid = true
    }
    catch {
        resultValid = false
        print(error)
    }
    return resultValid
}

当我打印它打印的路径时

file:///var/mobile/Containers/Data/Application/01EB6A70-34C6-4481-BE5B-7F7AB5E6703F/Documents/ts_20161221145652.png

我认为这是正确的。如果一切正常，它会改变屏幕上的图像，但它永远不会改变，并且 imageStringPathSet 也没有设置，这是一个类变量。任何人都知道我需要做什么才能让它发挥作用？

解决方案

原来原因是我在 viewWillAppear 中重置了 View 中的所有内容。解决此问题后，一切正常。感谢大家的反馈。希望这可以帮助其他人不要做我所做的事情。

Answer 1

根据评论中的要求，这是我的代码，(a) 使用 UIImagePickerController 从相机胶卷中选择，然后 (b) 使用 UIActivityViewController 让用户选择几种可能的方式来保存/附加图像到多个输出源。

虽然这不会保存到文档目录，但它可能是更好的选择。请注意代码 list 后的一些注释。

我的“选择” View Controller ，允许用户从相机胶卷中选择或拍照:

extension SelectViewController: UIImagePickerControllerDelegate, UINavigationControllerDelegate {

    // MARK: Camera App

    func openCameraApp() {
        if UIImagePickerController.availableCaptureModes(for: .rear) != nil {
            picker.allowsEditing = false
            picker.sourceType = UIImagePickerControllerSourceType.camera
            picker.cameraCaptureMode = .photo
            picker.modalPresentationStyle = .fullScreen
            present(picker,
                    animated: true,
                    completion: nil)
        } else {
            noCamera()
        }
    }
    func noCamera(){
        let alertVC = UIAlertController(
            title: "No Camera",
            message: "Sorry, this device has no camera",
            preferredStyle: .alert)
        let okAction = UIAlertAction(
            title: "OK",
            style:.default,
            handler: nil)
        alertVC.addAction(okAction)
        present(
            alertVC,
            animated: true,
            completion: nil)
    }

    // MARK: Photos Albums

    func showImagePicker() {
        picker.allowsEditing = false
        picker.sourceType = .photoLibrary
        //        picker.modalPresentationStyle = .Popover
        present(picker,
                animated: true,
                completion: nil)
        picker.popoverPresentationController?.sourceView = self.view
    }
    func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) {
        let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
        image = chosenImage
        self.performSegue(withIdentifier: "ShowEditView", sender: self)
        dismiss(animated: true, completion: nil)
    }
    func imagePickerControllerDidCancel(_ picker: UIImagePickerController) {
        dismiss(animated: false, completion: nil)
    }

    // MARK: Seque to EditViewController

    override func prepare(for segue: UIStoryboardSegue, sender: Any?) {
        if segue.identifier == "ShowEditView" {
            if let vc = segue.destination as? EditViewController {
                vc.image = image
            }
        }
    }
}

我的“编辑” View Controller 嵌入在 UINavigationBar 中，上面有一个按钮设置为 System Item == Action:

// MARK: Image actions

@IBAction func shareImage(_ sender: UIBarButtonItem) {
    let context = CIContext()
    let final = context.createCGImage(imgEdited, from: imgEdited.extent)
    let shareImage = UIImage(cgImage: final!)
    let vc = UIActivityViewController(activityItems: [shareImage], applicationActivities: [])
    vc.excludedActivityTypes =  [
        //UIActivityTypePostToTwitter,
        //UIActivityTypePostToFacebook,
        UIActivityType.postToWeibo,
        //UIActivityTypeMessage,
        //UIActivityTypeMail,
        UIActivityType.print,
        //UIActivityTypeCopyToPasteboard,
        UIActivityType.assignToContact,
        //UIActivityTypeSaveToCameraRoll,
        UIActivityType.addToReadingList,
        //UIActivityTypePostToFlickr,
        UIActivityType.postToVimeo,
        UIActivityType.postToTencentWeibo
    ]
    present(vc,
                            animated: true,
                            completion: nil)
    vc.popoverPresentationController?.sourceView = self.view
    vc.completionWithItemsHandler = {(activity, success, items, error) in
    }
}

注意事项:

• 请记住，在 iOS 10 设备中使用 UIImagePickerController 时，它会崩溃，除非您将它添加到您的 info.plist:

  <key>NSCameraUsageDescription</key>
  <string>Used to capture new image for photo effect</string>
  <key>NSPhotoLibraryUsageDescription</key>
  <string>Used to select an image for photo effect</string>
  

  您可以在标签中使用您想要的任何内容。

• UIActivityViewController 将在其excludedActivityTypes 中显示所有已注释 的选项。 (我列出这些选项只是为了 self 记录。)如果用户有 Facebook 并想在上面发帖，如果他们还没有登录，系统会提示他们登录。