问题描述
我的 Xamarin.iOS 应用程序中有图片上传功能。我已将此上传的图像存储在 firebase 存储中。我的文件成功上传到 firebase 存储,但问题是:
当我尝试使用 firebase 的 listAll() 方法获取所有图像时 存储它不会返回所有图像,直到文件夹有图像 >= 2。
private void ImagePicker_FinishedPickingMedia(object sender,UIImagePickerMediaPickedEventArgs e)
{
if (e.Info[UIImagePickerController.MediaType].ToString() == "public.image")
{
NSData imgData = new NSData();
imgData = e.OriginalImage.AsJPEG();
Guid uniqId = Guid.NewGuid(); // use - uniqId.ToString()
FirebaseClient.Instance.UploadAdventurePhoto(imgData,this.Adventure.Id,uniqId.ToString());
//(Path of folder - gs://myapp.appspot.com/adventures/00ac45a3-7c92-4335-a4b8-b9b705c4dd72)
StorageReference photsUrl = Storage.DefaultInstance.GetReferenceFromUrl($"gs://myapp.appspot.com/adventures/{this.Adventure.Id}");
photsUrl.ListAll(this.Handler);
}
this.imagePicker.dismissViewController(true,null);
}
// Add image to Firestore collection's Document.
private async void Handler(StorageListResult result,NSError arg2)
{
foreach (var image in result.Items)
{
// Logic to append image to Firestore document.
}
}
/// <param name="imgData">Selected image that needs to be stored on storage.</param>
/// <param name="adventureId">Name of the folder.</param>
/// <param name="imageName">By this name image will get stored in folder.</param>
public void UploadAdventurePhoto(NSData imgData,string adventureId,string imageName)
{
StorageReference adventurePictureRef = Storage.DefaultInstance.GetReferenceFromPath($"adventures/{adventureId}/{imageName}");
StorageMetadata MetaData = new StorageMetadata();
MetaData.ContentType = "image/jpg";
adventurePictureRef.PutData(imgData,MetaData);
}
上传第一张图片后,图片上传成功,但当处理程序被调用时,它会给出以下响应:
但是在此之后,当我上传第二张图片时,它会响应 Firebase.Storage.StorageReference1:
表示如果有两个图像,则仅返回 url 引用。如何解决这个问题?
我已经在存储规则中添加了rules_version = '2';。
解决方法
还没有找到 listAll() 的解决方案,但我已经解决了这个问题。
我试图使用 listAll() 从 firebase 存储中获取所有图像,但我遇到了这个问题。所以现在我使用 PutData() 方法的完成处理程序代替 listAll()。
完成处理程序将为您提供上传图像的元数据。从这个元数据我们可以像这样直接得到图像: 元数据名称
这是我通过在 UploadAdventurePhoto() 方法中添加完成处理程序来解决问题的方法:
private void UploadAdventurePhoto(NSData imgData,string folderName,string imageName)
{
StorageReference adventurePictureRef = Storage.DefaultInstance.GetReferenceFromPath($"adventures/{folderName}/{imageName}");
StorageMetadata metaData = new StorageMetadata();
metaData.ContentType = "image/jpeg";
adventurePictureRef.PutData(imgData,metaData,this.HandleStorageGetPutUpdateCompletion);
}
private async void HandleStorageGetPutUpdateCompletion(StorageMetadata metadata,NSError error)
{
if (error != null)
{
// Uh-oh,an error occurred!
return;
}
var url = metadata.Name;
var downloadUrl = metadata.Path;
Debug.WriteLine($"Image url - {url}\n Path-{downloadUrl}");
CollectionReference collectionRef = Firestore.SharedInstance.GetCollection(FirebaseClient.AdventuresCollection);
var docRef = collectionRef.GetDocument(this.Adventure.Id);
var keys = new NSString[]
{
new NSString($"{AdventureBase.PhotoPropName}"),};
var value = new NSObject[]
{
new NSString(url),};
var objects = new NSObject[]
{
FieldValue.FromArrayUnion(value),};
var dict = new NSDictionary<NSString,NSObject>(keys,objects);
await docRef.SetDataAsync(dict,true);
docRef.AddSnapshotListener(this.UpdateDataHandler);
}
private async void UpdateDataHandler(DocumentSnapshot snapshot,NSError error)
{
if (error != null)
{
// something went wrong
Debug.WriteLine($"Error - {error.Description}");
return;
}
Toast.MakeToast("Image uploaded successfully").Show();
}