无法与iCloud同步简单文本文件(错误的文件描述符)

Question

我在同步一个简单的文本文件时遇到问题,我在尝试打开它时遇到此错误:

{NSFilePath =/private/var/mobile/Library/Mobile Documents/4C224W52W5~com~piso13~opusDomini/currentLogPath,NSUnderlyingError = 0xde9b460"操作无法完成.错误的文件描述符"}

这就是我创建它的方式

-(BOOL)createLogFolderFile{        

    NSString *uuid = nil;

    CFUUIDRef uuidRef = CFUUIDCreate(nil);

    uuid = (NSString*)CFUUIDCreateString(nil, uuidRef);

    CFRelease(uuidRef);    



    NSError *error = nil;

    [uuid writeToFile:[self filePath] atomically:NO encoding:NSUTF8StringEncoding error:&error];

    if (error) {

        NSLog(@"Error trying to create log file %@", error);        

        return FALSE;

    }

    else{

        return TRUE;

    }

}

-(NSString*)filePath{

    NSFileManager *fileManager = [NSFileManager defaultManager];

    NSString *iCloudPath = [[fileManager URLForUbiquityContainerIdentifier:nil] path];

    return [iCloudPath stringByAppendingPathComponent:LOG_FOLDER_FILE_NAME];

}

这就是我读它的方式:

-(NSString*)readLogFolderFromFile{

    NSError *error = nil;

    NSString *logFolder = [NSString stringWithContentsOfFile:[self filePath] encoding:NSUTF8StringEncoding error:&error];

    if (error) {

        NSLog(@"Error when trying to read log folder from file: %@" ,error);

        return nil;

    }

    else{

        return logFolder;

    }

}

我正在使用NSMetadataQuery来搜索文件,通知查询完成收集信息结果为正.

救命？

Answer 1

该文件未下载.似乎NSMetadataQuery通知云中文件的存在.要实际获取文件,需要额外的代码:

里面的queryDidFinish收集通知:

 NSMetadataItem *item = [query resultAtIndex:0];
        self.metadataItem = item;
        BOOL isDownloaded = [[item valueForAttribute:NSMetadataUbiquitousItemIsDownloadedKey]boolValue];

  if (!isDownloaded) {
        NSError *error = nil;
        [[NSFileManager defaultManager] startDownloadingUbiquitousItemAtURL: [item valueForAttribute:NSMetadataItemURLKey] error:&error];
        NSLog(@"Start downloading file");
        if (error) {
            NSLog(@"Error trying to download file: %@", error);
        }
        else{
            [self lookForLogFolderFile];
            return;
        }

    }

lookForLogFolderFile只是再次启动查询.几次调用后,我的项目被下载.您还可以在每次调用之间使用计时器来启动NSMetadataQuery.就我而言,只是一个包含一行的文本文件.