WP8.1 background file transfer

Computer Store News: The Background Transfer Service allows an application to queue multiple file transfer requests so that when the application is no longer running in the foreground, the request can continue. File downloads and uploads are supported. WP has always been able to transfer files in the background, except for some system-level applications, which support few third-party applications that can be transmitted in the background.

Have you ever complained that Weibo can't post a lock screen with pictures? QQ pass a file to the background KISS? Must I keep staring at the download bar when downloading a song?

Next, let everyone touch the depth of the doorway file transfer! With Windows Phone OS 7.1, applications can queue one or more file uploads or downloads using HTTP, which are performed in the background, even when the application is no longer running in the foreground. Use the API for launching file transfers to query the status of existing transfers and provide progress indicators to end users.

The following picture shows a multi-threaded (background) download of the app store app download and the third-party music app MUSIC.

• Background transfer API background transfer service of course need the corresponding API to work, click here MSDN link

• Supported transfer method background transfer service only supports use HTTP and HTTPS transmission. FTP is not supported. Set the transfer method to upload or download files in the background.

• The file system restricts all background transfers to require a local file path. The download requires a target path that specifies where the downloaded file will be saved. The upload requires a source path that specifies the location from which the file will be uploaded. All local paths for background transfers must be in separate storage for your application.

• Once the completion time meets the requirements of the property settings and the system requirements related to battery power and available connections, background transfers initiated via the background transfer API will begin. It can also be set to transmit when a Wi-Fi connection is available and when the device is connected to an external power source.

• The application requires that applications that use background file transfer must meet other certification requirements in order to list the application in the store in addition to the requirements of the regular application. When designing and implementing an application, you should consider other requirements for these specific application types such as: perceptual targeting, running applications under lock screen, music and video, photos, and more.

• Background Transfer Restrictions The operating system imposes many restrictions on background transfers related to file size, connection speed, and device resources.