iOS分享扩展-发送大视频

Question

所以我正在尝试发送一个大视频文件(超过 100 mb)，每当我使用 dataWithContentsOfURL 访问视频文件时，扩展都会终止。这适用于较小的文件。

我该如何解决？

if ([itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypeMovie]){
            [itemProvider loadItemForTypeIdentifier:(NSString *)kUTTypeMovie options:nil completionHandler:urlHandler];
}




NSItemProviderCompletionHandler urlHandler = ^(NSURL *item, NSError *error) {

  if ([itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypeVideo] | [itemProvider hasItemConformingToTypeIdentifier:(NSString *)kUTTypeMovie])
  {
        NSData *fileData = [NSData dataWithContentsOfURL:item]

        // ----> fileData WORKS for small files.
        // ----> for large files, extension QUITS - without any trace - and control does not proceed after this. This may be due to memory pressure?  

        [_shareExtensionActionsManager sendTextMessage:contentText attachmentData:fileData attachmentName:@"video-1" toChatEntity:_selectedItem completion:^(BOOL success) 
               {
                 [self.extensionContext completeRequestReturningItems:nil completionHandler:^(BOOL expired) {
    exit(0);
}];
         }];  
   } 
};

Answer 1

来自app extension docs :

Users tend to return to the host app immediately after they finish their task in your app extension. If the task involves a potentially lengthy upload or download, you need to ensure that it can finish after your extension gets terminated.

和

After your app extension calls completeRequestReturningItems:completionHandler: to tell the host app that its request is complete, the system can terminate your extension at any time.

您将需要使用 NSURLSession 创建启动后台任务的 URL session 。

如果后台任务完成时您的扩展没有运行，系统将在后台启动包含您的应用程序并在您的 AppDelegate 中调用 application:handleEventsForBackgroundURLSession:completionHandler:。

您还需要设置一个 shared container您的扩展程序和包含的应用程序都可以访问。为此，您需要使用 NSURLSessionConfiguration 的 sharedContainerIdentifier 属性来指定容器的标识符，以便稍后访问它。

这是文档中的示例，显示了如何实现此目的:

NSURLSession *mySession = [self configureMySession];
   NSURL *url = [NSURL URLWithString:@"http://www.example.com/LargeFile.zip"];
   NSURLSessionTask *myTask = [mySession downloadTaskWithURL:url];
   [myTask resume];

- (NSURLSession *) configureMySession {
    if (!mySession) {
        NSURLSessionConfiguration* config = [NSURLSessionConfiguration backgroundSessionConfigurationWithIdentifier:@“com.mycompany.myapp.backgroundsession”];
// To access the shared container you set up, use the sharedContainerIdentifier property on your configuration object.
config.sharedContainerIdentifier = @“com.mycompany.myappgroupidentifier”;
        mySession = [NSURLSession sessionWithConfiguration:config delegate:self delegateQueue:nil];
    }
    return mySession;
}

这是一个 related resource这可能会有所帮助。