Question

For example, I am inside a building and i want to get my location with the accuracy of 0.75 (Criteria.ACCURACY_FINE) and this will use the gps if my gps is on. Since I am inside a building, gps won’t work.

How can I determine if it is really impossible to get a gps fix location?

Is onLocationChanged(Location arg0) will be called even though no gps fix location was received when using LocationListener?

Is it possible to use a timeout in requesting gps location so that I can shift to network as the location provider if i can’t get any location?

Answer 1

I see three basic possibilities:

1. Setup a LocationListener, and then
   determine it based upon calls to
   onStatusChanged. My concern here is
   that I’m not sure how well android
   is able to determine the difference
   between OUT_OF_SERVICE and
   TEMPORARILY_UNAVAILABLE. I would
   hope that its based upon signal
   strength, but its probably something
   to test.
2. Simply listen to both. If you haven’t
   heard from the (more accurate) gps provider
   in a certain period of time, then switch to the
   less reliable approaches. This may consume more power
   due to the requirement to monitor multiple location sources
   simultaneously, but is probably the most reliable method otherwise.
3. Some hybrid of 1 and 2 above (gps, but switch to local if no results for a while)… this might be the most efficient, but more difficult to implement.