“相机卷”和“我的照片流”的PHAssetCollection为空

Question

我正在尝试在我的iphone中显示所有相册标题的列表，当我按下一个标题时，我希望它在集合视图中显示该特定相册的所有照片。我正在使用"PhotosUI“框架，我使用以下代码来获取相册标题：

-(void)getLibrariesList
{
    NSArray *collectionsFetchResults;
    albumNames = [[NSMutableArray alloc] init];

    PHFetchResult *smartAlbums = [PHAssetCollection       fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum
                                                                                subtype:PHAssetCollectionSubtypeAlbumRegular options:nil];
    PHFetchResult *syncedAlbums = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum
                                                                           subtype:PHAssetCollectionSubtypeAlbumSyncedAlbum options:nil];
    PHFetchResult *userCollections = [PHCollectionList fetchTopLevelUserCollectionsWithOptions:nil];

    PHFetchOptions *userAlbumsOptions = [PHFetchOptions new];
    userAlbumsOptions.predicate = [NSPredicate predicateWithFormat:@"estimatedAssetCount > 0"];



    // Add each PHFetchResult to the array
    collectionsFetchResults = @[smartAlbums, userCollections, syncedAlbums];

    for (int i = 0; i < collectionsFetchResults.count; i ++) {

        PHFetchResult *fetchResult = collectionsFetchResults[i];

        for (int x = 0; x < fetchResult.count; x ++) {

            PHCollection *collection = fetchResult[x];

            albumNames[x] = collection.localizedTitle;

        }
    }
    //update the tableview
    [self.libraryTableView reloadData];
}

下面的代码通过标题获取特定相册的所有照片：

-(void)showPhotosInCollectionViewForALbumWithName:(NSString*)albumName
{
    libraryAssets = [NSMutableArray array];

    __block PHAssetCollection *collection;

    // Find the album
    PHFetchOptions *fetchOptions = [[PHFetchOptions alloc] init];
    fetchOptions.predicate = [NSPredicate predicateWithFormat:@"title = %@", albumName];
    collection = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeAlbum
                                                          subtype:PHAssetCollectionSubtypeAny
                                                          options:fetchOptions].firstObject;

    PHFetchResult *collectionResult = [PHAsset fetchAssetsInAssetCollection:collection options:nil];

    [collectionResult enumerateObjectsUsingBlock:^(PHAsset *asset, NSUInteger idx, BOOL *stop) {


        [libraryAssets addObject:asset];
    }];
    [self.libraryPhotosCollectoionView reloadData];
}

对于某些相册，它是有效的，像"Instagram“和我用手机创建的相册，但当我按下"Camera Roll”和"My Photo Stream“相册时，它不会显示任何内容。

你知道为什么会发生这种情况吗?或者有没有其他方法来获取我设备上的所有照片？

Answer 1

我有答案了。我检索所有的相机滚动照片和视频。下面是我的代码。

   PHFetchOptions *fetchOptions = [[PHFetchOptions alloc] init];
collection = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum
                                                      subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary
                                                      options:fetchOptions].firstObject;

collectionResult = [PHAsset fetchAssetsInAssetCollection:collection options:nil];
NSLog(@"Custom album images::%@",collectionResult);


[collectionResult enumerateObjectsUsingBlock:^(PHAsset *asset, NSUInteger idx, BOOL *stop)
{
    NSLog(@"Custom album::%@",asset);
    NSLog(@"Collection Result Count:%lu", (unsigned long)self.collectionResult.count);

    //add assets to an array for later use in the uicollectionviewcell
}];