UIActivityTypeMessage支持的格式

Question

iOS7.0中的UIActivityTypeMessage支持哪些文件格式类型。

我正在尝试创建一个录音机，因此希望使用iMessage共享以.m4a格式录制的音频。

请咨询可能的解决方案。另请注意，我已尝试使用UIActivityViewController和UIDocumentInteractionController，但iMessage选项不会弹出。

UIActivityViewController，

pathUrl = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"test" ofType:@"m4a"]];

controller = [[UIActivityViewController alloc] initWithActivityItems:@[pathUrl] applicationActivities:nil];
controller.excludedActivityTypes = @[UIActivityTypeAddToReadingList,UIActivityTypeAirDrop,UIActivityTypeAssignToContact,UIActivityTypeCopyToPasteboard,UIActivityTypePostToFacebook,UIActivityTypePostToFlickr,UIActivityTypePostToTencentWeibo,UIActivityTypePostToTwitter,UIActivityTypePostToVimeo,UIActivityTypePostToWeibo,UIActivityTypePrint,UIActivityTypeSaveToCameraRoll];

[self presentViewController:controller animated:YES completion:nil];

UIDocumentInteractionController，

interactionController = [UIDocumentInteractionController interactionControllerWithURL:pathUrl];
interactionController.delegate = self;
[interactionController presentOptionsMenuFromRect:CGRectMake(0.0f, 0.0f, 160.0f, 200.0f) inView:self.view animated:YES];