实时照片自动保存

Question

Xcode新手，正在尝试制作一个应用程序来下载实时墙纸。我使用github的LivePhotoDemo编写了所有的代码。我的问题是，当页面加载时，它会显示实时照片，但在我的相片库中保存了两个副本，而我似乎想不出如何获得一个保存按钮来代替它(并且只有一个副本)

import UIKit
import Photos
import PhotosUI
import MobileCoreServices


struct FilePaths {
static let documentsPath : AnyObject = NSSearchPathForDirectoriesInDomains(.cachesDirectory,.userDomainMask,true)[0] as AnyObject
struct VidToLive {
    static var livePath = FilePaths.documentsPath.appending("/")
}
}

class ViewController: UIViewController, 
UIImagePickerControllerDelegate, UINavigationControllerDelegate {
//@IBOutlet var livePhotoView: PHLivePhotoView!

@IBOutlet var livePhotoView: PHLivePhotoView!
    {
    didSet {
        loadVideoWithVideoURL(Bundle.main.url(forResource: "video", withExtension: "mov")!)
    }
}

func loadVideoWithVideoURL(_ videoURL: URL) {
    livePhotoView.livePhoto = nil
    let asset = AVURLAsset(url: videoURL)
    let generator = AVAssetImageGenerator(asset: asset)
    generator.appliesPreferredTrackTransform = true
    let time = NSValue(time: CMTimeMakeWithSeconds(CMTimeGetSeconds(asset.duration)/2, preferredTimescale: asset.duration.timescale))
    generator.generateCGImagesAsynchronously(forTimes: [time]) { [weak self] _, image, _, _, _ in
        if let image = image, let data = UIImage(cgImage: image).pngData() {
            let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
            let imageURL = urls[0].appendingPathComponent("image.jpg")
            try? data.write(to: imageURL, options: [.atomic])

            let image = imageURL.path
            let mov = videoURL.path
            let output = FilePaths.VidToLive.livePath
            let assetIdentifier = UUID().uuidString
            let _ = try? FileManager.default.createDirectory(atPath: output, withIntermediateDirectories: true, attributes: nil)
            do {
                try FileManager.default.removeItem(atPath: output + "/IMG.JPG")
                try FileManager.default.removeItem(atPath: output + "/IMG.MOV")

            } catch {

            }
            JPEG(path: image).write(output + "/IMG.JPG",
                                    assetIdentifier: assetIdentifier)
            QuickTimeMov(path: mov).write(output + "/IMG.MOV",
                                          assetIdentifier: assetIdentifier)

            //self?.livePhotoView.livePhoto = LPDLivePhoto.livePhotoWithImageURL(NSURL(fileURLWithPath: FilePaths.VidToLive.livePath.stringByAppendingString("/IMG.JPG")), videoURL: NSURL(fileURLWithPath: FilePaths.VidToLive.livePath.stringByAppendingString("/IMG.MOV")))
            //self?.exportLivePhoto()
            _ = DispatchQueue.main.sync {
                PHLivePhoto.request(withResourceFileURLs: [ URL(fileURLWithPath: FilePaths.VidToLive.livePath + "/IMG.MOV"), URL(fileURLWithPath: FilePaths.VidToLive.livePath + "/IMG.JPG")],
                                    placeholderImage: nil,
                                    targetSize: self!.view.bounds.size,
                                    contentMode: PHImageContentMode.aspectFit,
                                    resultHandler: { (livePhoto, info) -> Void in
                                        self?.livePhotoView.livePhoto = livePhoto
                                        self?.exportLivePhoto()
                })
            }
        }
    }
}

 @IBAction func Savephoto(_ sender: UIBarButtonItem){
  }
  func exportLivePhoto () {
    PHPhotoLibrary.shared().performChanges({ () -> Void in
        let creationRequest = PHAssetCreationRequest.forAsset()
        let options = PHAssetResourceCreationOptions()


        creationRequest.addResource(with: PHAssetResourceType.pairedVideo, fileURL: URL(fileURLWithPath: FilePaths.VidToLive.livePath + "/IMG.MOV"), options: options)
        creationRequest.addResource(with: PHAssetResourceType.photo, fileURL: URL(fileURLWithPath: FilePaths.VidToLive.livePath + "/IMG.JPG"), options: options)

    }, completionHandler: { (success, error) -> Void in
        if !success {
            NSLog((error?.localizedDescription)!)
        }
    })
}
}

我的主视图链接到顶部的IBOutlet，保存按钮链接到底部附近的IBAction。几年前，除了一些超文本标记语言和C++之外，我对编码几乎一无所知。我只知道如何查看代码，并试图理解每件事。有人能告诉我我哪里做错了吗？非常感谢!

Answer 1

这里有几件事可以让你摆脱困境。

问题1:如何让保存按钮调用exportLivePhoto()：

您的按钮的IBAction应如下所示：

  @IBAction func savePhotoTapped(_ sender: Any) {
    print("in savePhotoTapped | start"
    exportLivePhoto()
  }

确保此操作已连接到您在情节提要中创建的按钮。

问题2:多个保存：

这些行看起来像是保存了图像的jpg和mov版本。如果你只想要一个注释而不是另一个。

try FileManager.default.removeItem(atPath: output + "/IMG.JPG")
try FileManager.default.removeItem(atPath: output + "/IMG.MOV")

也可以试着清理你的代码，以便将来更容易阅读。