>下载一些内容
>同步一些元素,
>当应用程序打开时,直接通知用户

请注意,您的时间限制在30秒.

配置静默通知

To support silent remote notifications,add the remote-notification value to the UIBackgroundModes array in your Info.plist file. To learn more about this array,see UIBackgroundModes.

<key>UIBackgroundModes</key>
<array>
<string>remote-notification</string>
</array>

Configuring a Silent Notification

The aps dictionary can also contain the content-available property. The content- available property with a value of 1 lets the remote notification act as a silent notification. When a silent notification arrives,iOS wakes up your app in the background so that you can get new data from your server or do background information processing. Users aren’t told about the new or changed information that results from a silent notification,but they can find out about it the next time they open your app.

For a silent notification,take care to ensure there is no alert,sound,or badge payload in the aps dictionary. If you don’t follow this guidance,the incorrectly-configured notification might be throttled and not delivered to the app in the background,and instead of being silent is displayed to the user