如何从 UIImagePickerController 获取授权的 PHAsset？

Posted 2023-03-08

【中文标题】如何从 UIImagePickerController 获取授权的 PHAsset？

【英文标题】：How to get an authorized PHAsset from UIImagePickerController?

【发布时间】：2018-06-03 19:19:07

【问题描述】：

我有这个代码：

@IBAction func importButtonPressed(_ sender: Any) 
        self.imagePicker.sourceType = .photoLibrary
        self.imagePicker.allowsEditing = true
        self.imagePicker.mediaTypes = [kUTTypeMovie as String, kUTTypeImage as String]

        self.present(self.imagePicker,animated: true, completion: nil)

这完美地呈现了 UIImagePicker。然后，当我想使用选择的项目来说出 PHAsset 的日期时：

func imagePickerController(_ picker: UIImagePickerController, didFinishPickingMediaWithInfo info: [String : Any]) 
        guard info[UIImagePickerControllerMediaType] != nil else  return 
        let mediaType = info[UIImagePickerControllerMediaType] as! CFString
        switch mediaType 
        case kUTTypeImage:
            if let pickedImage = info[UIImagePickerControllerOriginalImage] as? UIImage 
                ...
            
            break
        case kUTTypeMovie:
            if let videoURL = info[UIImagePickerControllerMediaURL] as? URL, let pickedAsset = info[UIImagePickerControllerPHAsset] as? PHAsset 
                print("kUTTypeMovie")
                MyVariables.isScreenshot = false
                let creationDate = pickedAsset.creationDate
                print(creationDate,"creationDate")
            
            break
        case kUTTypeLivePhoto:
            print("livePhoto")
            dismiss(animated: true, completion: nil)

            break
        default:
            dismiss(animated: true, completion: nil)

            print("something else")
            break
        
    

现在，例如，当我选择一个视频时，print("kUTTypeMovie") 失败了，我想是因为 let pickedAsset = info[UIImagePickerControllerPHAsset] as? PHAsset 失败了

在其他地方 (UIImagePickerControllerDelegate get date from picked image in ios 11) 我看到这可能是因为我需要授权才能选择 PHAsset。

所以我将我的第一个代码块更改为：

@IBAction func importButtonPressed(_ sender: Any) 

        let status = phphotoLibrary.authorizationStatus()

        switch status 
        case .authorized:
            PHPhotoLibrary.requestAuthorization(status in
                if status == .authorized 
                    self.imagePicker.sourceType = .photoLibrary
                    self.imagePicker.allowsEditing = true
                    self.imagePicker.mediaTypes = [kUTTypeMovie as String, kUTTypeImage as String]

                    self.present(self.imagePicker,animated: true, completion: nil)
                
            )
        case .denied:
            print("denied")
        // probably alert the user that they need to grant photo access
        case .notDetermined:
            print("not determined")
        case .restricted:
            print("restricted")
            // probably alert the user that photo access is restricted
        

    

但是现在当我按下导入按钮时，它会因 lldb 错误而崩溃：

libsystem_kernel.dylib`__abort_with_payload:
    0x1854f7040 <+0>:  mov    x16, #0x209
    0x1854f7044 <+4>:  svc    #0x80
->  0x1854f7048 <+8>:  b.lo   0x1854f7060               ; <+32>
    0x1854f704c <+12>: stp    x29, x30, [sp, #-0x10]!
    0x1854f7050 <+16>: mov    x29, sp
    0x1854f7054 <+20>: bl     0x1854d8bdc               ; cerror_nocancel
    0x1854f7058 <+24>: mov    sp, x29
    0x1854f705c <+28>: ldp    x29, x30, [sp], #0x10
    0x1854f7060 <+32>: ret    

很明显，我没有正确地做到这一点。我该怎么做？

【参考方案1】：

崩溃是因为下面缺少访问照片库的权限，

此应用已崩溃，因为它试图在没有使用说明的情况下访问隐私敏感数据。应用的 Info.plist 必须包含一个 NSPhotoLibraryUsageDescription 键和一个字符串值，向用户解释应用如何使用这些数据。

在您的Info.plist 中，添加NSPhotoLibraryUsageDescription 键，并附上如下说明，这样就可以正常工作了

编辑 您还应该按照以下正确方式使用PhotoLibrary 授权。

@IBAction func importButtonPressed(_ sender: Any) 

    PHPhotoLibrary.requestAuthorization(status in
        switch status 
        case .authorized:
            self.imagePicker.sourceType = .photoLibrary
            self.imagePicker.allowsEditing = true
            self.imagePicker.mediaTypes = [kUTTypeMovie as String, kUTTypeImage as String]

            self.present(self.imagePicker,animated: true, completion: nil)
        case .denied:
            print("denied")
        // probably alert the user that they need to grant photo access
        case .notDetermined:
            print("not determined")
        case .restricted:
            print("restricted")
            // probably alert the user that photo access is restricted
        
    )