使用 getThumbnailBatch 获取 Dropbox 缩略图答案

【问题标题】：get dropbox thumbnails with getThumbnailBatch使用 getThumbnailBatch 获取 Dropbox 缩略图
【发布时间】：2020-05-13 04:01:56
【问题描述】：

我正在使用 Dropbox objc API，我正在尝试获取特定 Dropbox 文件夹中的所有缩略图。

但我完全卡在 DBFILESGetThumbnailBatchArg 上。如何启动文件夹中所有图像的路径？

这是我坚持的路线：

    [[client.filesRoutes getThumbnailBatch:<#(nonnull NSArray<DBFILESThumbnailArg *> *)#>] 
setResponseBlock:^(
DBFILESGetThumbnailBatchResult * _Nullable result, 
DBFILESGetThumbnailBatchError * _Nullable routeError, 
DBRequestError * _Nullable networkError) { etc etc..

文档说

DBFILESThumbnailArg *arg = [[DBFILESThumbnailArg alloc] initWithPath:<#(nonnull NSString *)#>];


DBFILESGetThumbnailBatchArg *batchArg = [[DBFILESGetThumbnailBatchArg alloc] 
initWithEntries:<#(nonnull NSArray<DBFILESThumbnailArg *> *)#>];

如何初始化 DBFILESThumbnailArg 的路径列表？

文档链接： https://dropbox.github.io/dropbox-sdk-obj-c/api-docs/latest/Classes/DBFILESRouteObjects.html#/c:objc(cs)DBFILESRouteObjects(cm)DBFILESGetThumbnailBatch

【问题讨论】：

标签： ios objective-c thumbnails dropbox-api

【解决方案1】：

如您所见，the getThumbnailBatch method 需要 NSArray<DBFILESThumbnailArg *>，因此调用它看起来像这样：

NSArray<DBFILESThumbnailArg *> *entries = @[[[DBFILESThumbnailArg alloc] initWithPath:@"/test1.jpg"], [[DBFILESThumbnailArg alloc] initWithPath:@"/test2.jpg"]];
[[client.filesRoutes getThumbnailBatch:entries]
 setResponseBlock:^(DBFILESGetThumbnailBatchResult *result, DBFILESGetThumbnailBatchError *routeError, DBRequestError *networkError) {
    if (result) {
        NSLog(@"result:");
        NSLog(@"%@", result);
    } else if (routeError) {
        NSLog(@"routeError:");
        NSLog(@"%@", routeError);
    } else if (networkError) {
        NSLog(@"networkError:");
        NSLog(@"%@", networkError);
    };
}];

【讨论】：

是的，但是当上传或删除新的图像时，图像的数量会发生变化，我需要一个更动态的代码。 NSArray *entries，应该是 NSArray *entries

【解决方案2】：

我使用 NSMutableArray 解决了这个问题，如果其他人来找我，请发布我的解决方案：

    //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);
            }

【讨论】：