为什么不推荐使用PHPicker

var config = PHPickerConfiguration()
// 可选择的资源数量，0表示不设限制，默认为1
config.selectionLimit = 0
// 可选择的资源类型
// 只显示图片（注：images 包含 livePhotos）
config.filter = .images
// 显示 Live Photos 和视频（注：livePhotos 不包含 images）
config.filter = .any(of: [.livePhotos, .videos])
// 如果要获取视频，最好设置该属性，避免系统对视频进行转码
config.preferredAssetRepresentationMode = .current

let picker = PHPickerViewController(configuration: config)
picker.delegate = self
present(picker, animated: true, completion: nil)复制代码

@available(iOS 14, *)
public protocol PHPickerViewControllerDelegate : AnyObject {
    func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult])
}复制代码

func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
    // 首先需要 dismiss picker
    picker.dismiss(animated: true, completion: nil)
    for result in results {
        // 判断类型是否为 UIImage
        if result.itemProvider.canLoadObject(ofClass: UIImage.self) {
            // 确认类型后，调用 loadObject 方法获取图片
            result.itemProvider.loadObject(ofClass: UIImage.self) { (data, error) in
                // 回调结果是在异步线程，展示时需要切换到主线程
                if let image = data as? UIImage {
                    DispatchQueue.main.async {
                        self.showImage(image)
                    }
                }
            }
        }
    }
}复制代码

func picker(_ picker: PHPickerViewController, didFinishPicking results: [PHPickerResult]) {
    // 首先需要 dismiss picker
    picker.dismiss(animated: true, completion: nil)
    for result in results {
        if result.itemProvider.canLoadObject(ofClass: UIImage.self) {
            // 判断类型是否为 UIImage
            ...
        } else {
            // 类型为 Video
            // 调用 loadFileRepresentation 方法获取视频的 url
            // 这里 Type Identifier 我们用 UTType.movie.identifier (“public.movie”) 这个 UTI 可以获取所有格式的视频
            result.itemProvider.loadFileRepresentation(forTypeIdentifier: UTType.movie.identifier) { (url, error) in
                if let error = error {
                    print(error)
                    return
                }
                // 系统会将视频文件存放到 tmp 文件夹下
                // 我们必须在这个回调结束前，将视频拷贝出去，一旦回调结束，系统就会把视频删掉
                // 所以一定要确定拷贝结束后，再切换到主线程做 UI 操作
                // 另外不用担心视频过大而导致拷贝的时间很久，系统将创建一个 APFS 的克隆项，因此拷贝的速度会非常快
                guard let url = url else { return }
                let fileName = "\(Int(Date().timeIntervalSince1970)).\(url.pathExtension)"
                let newUrl = URL(fileURLWithPath: NSTemporaryDirectory() + fileName)
                try? FileManager.default.copyItem(at: url, to: newUrl)
                DispatchQueue.main.async {
                    self.playVideo(newUrl)
                }
            }
        }
    }
}复制代码

public enum SourceType : Int {
    @available(iOS, introduced: 2, deprecated: 100000, message: "Will be removed in a future release, use PHPicker.")
    case photoLibrary = 0
    case camera = 1
    @available(iOS, introduced: 2, deprecated: 100000, message: "Will be removed in a future release, use PHPicker.")
    case savedPhotosAlbum = 2
}复制代码

let viewController = self
PHPhotoLibrary.shared().presentLimitedLibraryPicker(from: viewController)复制代码

let viewController = self
// 开始监听
PHPhotoLibrary.shared().register(viewController) 
// 结束监听
PHPhotoLibrary.shared().unregisterChangeObserver(viewController)复制代码

/// 回调方法
func photoLibraryDidChange(_ changeInstance: PHChange) {
    // Your code
}复制代码

public enum PHAccessLevel : Int {
    case addOnly = 1
    case readWrite = 2
}复制代码

let level: PHAccessLevel = .readWrite
// 获取权限
PHPhotoLibrary.requestAuthorization(for: level) { status in
  // Your code
}
// 查看权限
let status: PHAuthorizationStatus = PHPhotoLibrary.authorizationStatus(for: level)复制代码

public enum PHAuthorizationStatus : Int {
    case notDetermined = 0
    case restricted = 1
    case denied = 2
    case authorized = 3
    @available(iOS 14, *)
    case limited = 4
}复制代码