ios - 从 iCloud Document Picker 附加 iWork 文档不起作用，因为它们是目录而不是文件

Question

将任何 iWork 文档(Pages、Keynote、Numbers)转换为 NSData来自 UIDocumentPickerViewController似乎不起作用，因为它们不是文件而是目录。

这是我的代码:

NSString *fileName = [[url path] lastPathComponent];
NSData *fileData = [[NSFileManager defaultManager] contentsAtPath:[docPickerUrl path]];
NSString *fileExtension = [docPickerUrl pathExtension];
NSString *UTI = (__bridge_transfer NSString *)UTTypeCreatePreferredIdentifierForTag(kUTTagClassFilenameExtension, (__bridge CFStringRef)fileExtension, NULL);
NSString *contentType = (__bridge_transfer NSString *)UTTypeCopyPreferredTagWithClass((__bridge CFStringRef)UTI, kUTTagClassMIMEType);

文件数据始终为 nil自从 NSFileManager无法将目录转换为数据。

我得到 url来自 - (void)documentPicker:(UIDocumentPickerViewController *)controller didPickDocumentAtURL:(NSURL *)url

Answer 1

我建议通过 NSFileCoordinator 对象，这是访问安全范围文件(例如通过 Dropbox 和 iCloud 的文件)所需的 AFAIK。 (在这种情况下，取消注释下面代码中的第一行和倒数第二行。)options NSFIleCoordinator 的 coordinateReadingItemAtURL: 所需的参数是 NSFileCoordinatorReadingForUploading .这将正常读取单个文件，但会自动将目录转换为 zip 文件。脱掉.zip添加后，您将拥有一个有效的 Pages/Numbers/Keynote 文件。 (它也有效。)

- (void)documentPicker:(UIDocumentPickerViewController *)controller didPickDocumentAtURL:(NSURL *)url {
  //[url startAccessingSecurityScopedResource]; // Necessary for security-scoped files
  NSFileCoordinator *coordinator = [[NSFileCoordinator alloc] init];
  NSError *error;
  __block NSData *fileData;

  [coordinator coordinateReadingItemAtURL:url options:NSFileCoordinatorReadingForUploading error:&error byAccessor:^(NSURL *newURL) {
     // File name for use in writing the file out later
     NSString *fileName = [newURL lastPathComponent];
     NSString *fileExtension = [newURL pathExtension];

     // iWork files will be in the form 'Filename.pages.zip'
     if([fileExtension isEqualToString:@"zip"]) {
       if([[[newURL URLByDeletingPathExtension] pathExtension] isEqualToString:@"pages"] ||
          [[[newURL URLByDeletingPathExtension] pathExtension] isEqualToString:@"numbers"] ||
          [[[newURL URLByDeletingPathExtension] pathExtension] isEqualToString:@"key"] ) {
         // Remove .zip if it is an iWork file
         fileExtension = [[newURL URLByDeletingPathExtension] pathExtension];
         fileName = [[newURL URLByDeletingPathExtension] lastPathComponent];
       }
     }

     NSError *fileConversionError;
     fileData = [NSData dataWithContentsOfURL:newURL options:NSDataReadingUncached error:&fileConversionError];

     // Do something with the file data here

  }
  //[url stopAccessingSecurityScopedResource]; // Necessary for security-scoped files
}

此处有关 NSFileCoordinator 选项的相关 Apple 文档:
https://developer.apple.com/library/ios/documentation/Foundation/Reference/NSFileCoordinator_class/#//apple_ref/c/tdef/NSFileCoordinatorReadingOptions