Location service object & location in general.

[Raymond Wells]

Location is a cross cutting concern in our application. We need to make this easy to get to and sadly the android API does not :).

We should have a service object in our app that allows us to easily track the user's location, and register callbacks to be triggered with location changes.

@engrMiguel @brandonthai2003 please comment with any suggestions.

I suggest the following, so we can also handle location both pull or push:

LocationService
  | --> setLocationChangedHandler
  | --> requestLocation(Callback)

[Raymond Wells]

I'll take this on in the next sprint. If you need a "location" for the time being, I suggest creating this object with stub methods.

I.e. the requestLocaiton method will just invoke the callback with either random or fixed data.

[Raymond Wells]

Also, like the other service objects, the constructor will take in a context. It's so we can have access to the same context the activity sees. :)

[Raymond Wells]

Hmm.. tracking location is pretty expensive on the battery. This might be something best done when polling for new ads.

[Raymond Wells]

Done.

LocationService.getInstance()  to get the current instance
LocationService.requestLocation // requests a single location returned in a callback

LocationService.requestConstantUpdates will request  locaiton updates.

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