如何在 Xamarin iOS 上从 iCloud 获取带有 PHVideo 的视频？

Question

我在 Xamarin.Forms 应用程序上使用 DependencyService 实现了多媒体选择器（用于图像和视频）。我对 iCloud 视频有疑问。 当我选择 icloud 上的视频时，我无法获取它。

我的实现是：

async void FinishedPickingAssets(object sender, MultiAssetEventArgs args)
         {
             IList<MediaFile> results = new List<MediaFile>();
             TaskCompletionSource<IList<MediaFile>> tcs = new TaskCompletionSource<IList<MediaFile>>();
    
             try 
             { 
                 var options = new PHImageRequestOptions()
                 {
                     NetworkAccessAllowed = true
                 };
    
                 options.Synchronous = false;
                 options.ResizeMode = PHImageRequestOptionsResizeMode.Fast;
                 options.DeliveryMode = PHImageRequestOptionsDeliveryMode.HighQualityFormat;
                 bool completed = false;
                 for (var i = 0; i < args.Assets.Length; i++)
                 {
                     var asset = args.Assets[i];
    
                     string fileName = string.Empty;
                     if (UIDevice.CurrentDevice.CheckSystemVersion(9, 0))
                     {
                         fileName = PHAssetResource.GetAssetResources(asset).FirstOrDefault().OriginalFilename;
                         fileName = Path.GetFileNameWithoutExtension(fileName) + "(" + i.ToString() + ")" + Path.GetExtension(fileName);
                     }
    
                     switch (asset.MediaType)
                     {
                         case PHAssetMediaType.Video:
                         {
                                 var vOptions = new PHVideoRequestOptions();
                                 vOptions.NetworkAccessAllowed = true;
                                 vOptions.Version = PHVideoRequestOptionsVersion.Original;
                                 vOptions.DeliveryMode = PHVideoRequestOptionsDeliveryMode.Automatic;
                                 string videoUrl = "";
    
                                 PHImageManager.DefaultManager.RequestAvAsset(asset, vOptions, (avAsset, audioMix, vInfo) => 
                                 {
                                     DispatchQueue.MainQueue.DispatchAsync(() => {
    
                                         var error = vInfo.ObjectForKey(PHImageKeys.Error);
                                            
                                         if (avAsset != null)
                                         {
                                             videoUrl = ((AVFoundation.AVUrlAsset)avAsset).Url.Path;
                                         }
                                         var meFile = new MediaFile()
                                         {
                                             FileName = fileName,
                                             FilePath = videoUrl
                                         };
    
                                         using (Stream source = File.OpenRead(videoUrl))
                                         {
                                             meFile.FileSize = source.Length;
                                         }
                                         results.Add(meFile);
                                         OnMediaPicked?.Invoke(this, meFile);
    
                                         if (args.Assets.Length == results.Count && !completed)
                                         {
                                             completed = true;
                                             tcs.TrySetResult(results);
                                         }
                                     });
                                 });
                         }
                         break;
                     default:
                         PHImageManager.DefaultManager.RequestImageData(asset, options, (data, dataUti, orientation, info) =>
                         {
    
                             string path = FileHelper.GetOutputPath(MediaFileType.Image, TemporalDirectoryName, fileName);
    
                             if (!File.Exists(path))
                             {
                                 Debug.WriteLine(dataUti);
                                 var imageData = data;
                                 imageData?.Save(path, true);
                             }
    
                             var meFile = new MediaFile()
                             {
                                 FileName = fileName,
                                 FilePath = path,
                                 FileSize = File.ReadAllBytes(path).Length
                             };
    
                             results.Add(meFile);
                             OnMediaPicked?.Invoke(this, meFile);
                             if (args.Assets.Length == results.Count && !completed)
                             {
                                 completed = true;
                                 tcs.TrySetResult(results);
                             }
    
                         });
                         break;
                     }
                 }
             }
             catch
             {
                 tcs.TrySetResult(results);
    
                 string automationId = "UnexpectedSituationMessage";
                 GeneralOperations.OpenToastMessage("Unexpected Situation", automationId);
             }
    
             mediaPickTcs?.TrySetResult(await tcs.Task);
         }

当我尝试选择 iCloud 对象时，我收到以下错误：

如何从 icloud 中拍摄多选视频？

提前谢谢你。

Answer 1

首先确保您已开启 iCloud 照片。

 1. Go to Settings > [your name] > iCloud.
 2. Tap Photos.
 3. If you need to, tap to turn on iCloud Photos.

然后检查视频和照片是否显示在您设备上的 Photo App 中。

对于多项选择和多项自定义，您可以从 nuget 安装插件 GMImagePicker.Xamarin。