抛个Notification 上去,但是不同于一般的Notification,她必须用setForeground来关掉。一般的cancel是不起作用的。
------解决方案--------------------
Running a Service in the Foreground A foreground service is a service that's considered to be something the user is actively aware of and thus not a candidate for the system to kill when low on memory. A foreground service must provide a notification for the status bar, which is placed under the "Ongoing" heading, which means that the notification cannot be dismissed unless the service is either stopped or removed from the foreground.
For example, a music player that plays music from a service should be set to run in the foreground, because the user is explicitly aware of its operation. The notification in the status bar might indicate the current song and allow the user to launch an activity to interact with the music player.
To request that your service run in the foreground, call startForeground(). This method takes two parameters: an integer that uniquely identifies the notification and the Notification for the status bar.