Android Polling from a Server periodically

问题:

I want to pull some data from a server every x minutes. IF the info contains certain information I would like to create a notification. I want this polling to happen even when the app is in the background, or the phone is asleep. I have a few questions about polling in android.

• What is the best way to go about doing it? Should I use an
  IntentService, an AlarmManager, something else?

• How often should I be polling the data? I would like to keep it relatively often, say under every 10 minutes.

回答1:

I would favour an AlarmManager as I try not to run continuously running services unless I really need to but it does really depend on how you will be using it.

If it were me I would (based on the limited description) :-

1. Set up an AlarmManager to fire in say 10 minutes.
2. In response to the alarm, start a service that polls the data.
3. After polling it should set itself up with a new Alarm to fire again in another 10 minutes.
4. The service shuts itself down.

回答2:

You'll want to use something like Cloud to Device Messaging (C2DM) (aka push notifications in the iPhone world)

A great tutorial can be found at http://blog.mediarain.com/2011/03/simple-google-android-c2dm-tutorial-push-notifications-for-android

回答3:

You could use Handler to listen the server. For example please check Run code over and over

回答4:

You could create a thread that does this. In your run method you could create a loop that polls the server every 10 minutes.