Я решил это с помощью NSMutableArray, опубликовав свое решение, если другие увидят:
//Create a temporary NSMutableArray
NSMutableArray *thumbArgMutable = [[NSMutableArray alloc] init];
for (NSString* image in _images)
{
//Create DBFILESThumbnailArg from NSString
DBFILESThumbnailArg *arg = [[DBFILESThumbnailArg alloc] initWithPath:image];
//Add path as DBFILESThumbnailArg to NSMutableArray
[thumbArgMutable addObject:arg];
}
//Copy NSMutableArray to a new DBFILESThumbnailArg
DBFILESThumbnailArg *thumbArg = [thumbArgMutable copy];
//create a DBFILESGetThumbnailBatchArg and init with the copied DBFILESThumbnailArg
DBFILESGetThumbnailBatchArg *thumbArgBatch = [[DBFILESGetThumbnailBatchArg alloc] initWithEntries:thumbArg];
DBUserClient *client = [[DBUserClient alloc] initWithAccessToken:@"TOKEN"];
//use property entries from DBFILESGetThumbnailBatchArg
[[client.filesRoutes getThumbnailBatch:thumbArgBatch.entries]
setResponseBlock:^(DBFILESGetThumbnailBatchResult * _Nullable result,
DBFILESGetThumbnailBatchError * _Nullable routeError,
DBRequestError * _Nullable networkError)
{
if (result) {
NSLog(@"%@\n", result);
//loop all downloaded thumbnails
for (DBFILESGetThumbnailBatchResultEntry *data in result.entries)
{
//extract data from each base64 encoded thumbnail string
NSData *thumbData = [[NSData alloc] initWithBase64EncodedString:data.success.thumbnail options:0];
//create UIImage from data
UIImage *thumbImage = [UIImage imageWithData:thumbData];
}
}
else { //if download failed
NSLog(@"%@\n%@\n", routeError, networkError);
}