让一个Service成为前置进程

在启动该Service的时候可以添加上如下方法：

@Overridepublic int onStartCommand(Intent intent,int flags,int startId){    Notification notification = Nitification(R.drawable.ic_launcher,"服务正在运行",System.currentTimeMillis());    Intent notificationIntent = new Intent(this,MainActivity.class);    PendingIntent pendingIntent.getActivity(this,0,notificationIntent,0);    notification.setLatestEventInfo(this,"消息标题","消息内容"，pendingIntent)；    startForeground(1,notification);    return super.onStartCommand(intent,flags,startId);}