Android Tidbits 6/21/2011: Unregister? Nah!

June 21, 2011 Joe Moore

C2DM Unregister Issues

It turns out when you follow the client-side C2DM unregistration process, this does not guarantee that those registration tokens are permanently unregistered for that device.

If we unregister as specified above and then send a push notification to that registration_id, the server receives an Error=NotRegistered as expected.

But, unexpectedly, when that device re-register with C2DM (and getting a new registration_id), the old registration_id is reactivated as well and can receive push notifications and does not result in a server-side Error=NotRegistered.

The end result: we implemented our server-side API to take both the new and old registration_ids when the Android client successfully registers with C2DM, allowing us to manually delete the old registration_id.

Drawable XML Files

Prefixing the name of a drawable xml file with “active_” seems to prevent android from using that drawable at all.

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