Question

我想从我的照片流中获取照片。我只有PHAsset的localIdentifier。

对于My Photo Stream相册以外的照片，我使用下面的代码来检索PHAsset。

[PHAsset fetchAssetsWithLocalIdentifiers:@[“localIdentifier”] options:nil].firstObject

localIdentifier就像“1BFC3BA2-AC95-403A-B4FF-B26AFB631581/L0/001”

它工作正常。但在我的My Photo Stream专辑中，我的PHAsset值为零。

有没有人知道我们如何使用PHAsset的localIdentifier值从My Photo Stream获取原始照片？

Answer 1

我自己得到了答案。我检索所有照片流照片并将其与特定的localIdentifier进行比较。以下是我的代码。

PHFetchOptions *userAlbumsOptions = [PHFetchOptions new];
            userAlbumsOptions.predicate = [NSPredicate predicateWithFormat:@"estimatedAssetCount > 0"];
            PHFetchResult *userAlbums = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumMyPhotoStream options:userAlbumsOptions];

            [userAlbums enumerateObjectsUsingBlock:^(PHAssetCollection *collection, NSUInteger idx1, BOOL *stop) {
                NSLog(@"album title %@", collection.localizedTitle);
                PHFetchOptions *fetchOptions = [PHFetchOptions new];
                fetchOptions.predicate = [NSPredicate predicateWithFormat:@"self.localIdentifier CONTAINS [cd] 'my identifier value'"];
                PHFetchResult *assetsFetchResult = [PHAsset fetchAssetsInAssetCollection:collection options:fetchOptions];
                [assetsFetchResult enumerateObjectsUsingBlock:^(PHAsset *asset, NSUInteger idx, BOOL *stop1) {
                    [[PHImageManager defaultManager] requestImageDataForAsset:asset options:option resultHandler:^(NSData * _Nullable imageData, NSString * _Nullable dataUTI, UIImageOrientation orientation, NSDictionary * _Nullable info) {
                        UIImage *imgResult = [UIImage imageWithData:imageData scale:1];
                    }];
                }];
            }]

Answer 2

请使用此链接http://qiita.com/to_obara/items/e386040abcc93842745b获取swift代码。我按照上面的链接编写了下面的客观c代码。

PHAsset *phAsset;
PHFetchOptions *optionsForFetch = [[PHFetchOptions alloc] init];;
optionsForFetch.includeHiddenAssets = YES;
NSURL *alURL = [info valueForKey: UIImagePickerControllerReferenceURL];
PHFetchResult *fetchResult = [PHAsset fetchAssetsWithALAssetURLs: @[alURL] options: nil];
if (fetchResult.count > 0) {
    return;
}

NSString *str = alURL.absoluteString;
NSString *localIDFragment = [[[[str componentsSeparatedByString: @"="] objectAtIndex: 1] componentsSeparatedByString: @"&"] objectAtIndex: 0];
PHFetchResult *fetchResultForPhotostream = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum subtype:PHAssetCollectionSubtypeAlbumMyPhotoStream options: nil];

if (fetchResultForPhotostream.count > 0) {
    PHAssetCollection *photostream = fetchResultForPhotostream [0];
    PHFetchResult *fetchResultForPhotostreamAssets = [PHAsset fetchAssetsInAssetCollection:photostream options:optionsForFetch];

    if (fetchResultForPhotostreamAssets.count > 0) {
        NSIndexSet *i = [NSIndexSet indexSetWithIndexesInRange: NSMakeRange(0, fetchResultForPhotostreamAssets.count)];
        //let i=NSIndexSet(indexesInRange: NSRange(location: 0,length: fetchResultForPhotostreamAssets.count))

      [fetchResultForPhotostreamAssets enumerateObjectsAtIndexes: i options: NSEnumerationReverse usingBlock:^(id  _Nonnull obj, NSUInteger idx, BOOL * _Nonnull stop) {
          PHAsset *target = obj;
          NSString *identifier = target.localIdentifier;
          if ([identifier rangeOfString: localIDFragment].length != 0) {
              if (target) {
                  // get photo info from this asset
                  PHImageRequestOptions * imageRequestOptions = [[PHImageRequestOptions alloc] init];
                  imageRequestOptions.synchronous = YES;
                  [[PHImageManager defaultManager]
                   requestImageDataForAsset:target
                   options:imageRequestOptions
                   resultHandler:^(NSData *imageData, NSString *dataUTI,
                                   UIImageOrientation orientation,
                                   NSDictionary *info)
                   {
                       if ([info objectForKey:@"PHImageFileURLKey"]) {
                           // path looks like this -
                           // file:///var/mobile/Media/DCIM/###APPLE/IMG_####.JPG
                           NSURL *path = [info objectForKey:@"PHImageFileURLKey"];
                           selectedImageName  = path.absoluteString;
                           [imagesDictArray addObject: [@{@"image": tempImage, @"imageUrl": selectedImageName} mutableCopy]];
                       }
                   }];
              }
              //
          }
            }];
    }
}

如何从我的照片流专辑中获取照片

2 个答案: