CSCI 370 Location and Geocoding

Location-based services

use real-time location data from a mobile device or smartphone to provide information, entertainment, or security

Android location frameworks

android.location, com.google.android.gms.location

com.google.android.gms.location

simpler API, greater accuracy, more power efficient, more versatile

ACCESS_COARSE_LOCATION

to access locations provided by cell tower/Wi-Fi triangulation, always include this permission

ACCESS_FINE_LOCATION

to access locations provided by GPS, include only if app benefits from precise location access

Location

represents a geographic location sensed at a particular time, consists of a latitude, a longitude, a UTC timestamp

Address

represents an address as a set of strings describing a location

Geocoder

translates between locations and addresses

open fun getLatitude(): Double

returns the latitude of this location in degrees

open fun getLongitude(): Double

returns the longitude of this location in degrees

open fun getTime(): Long

returns the Unix epoch time of this location in milliseconds since
January 1, 1970

open fun bearingTo(dest: Location): Float

returns the approximate bearing in degrees east of true north

open fun distanceTo(Location dest): Float

returns the approximate distance in meters between this location
and the given location

open fun getAltitude(): Double

returns the altitude of this location in meters

open fun getBearing(): Float

returns the bearing at the time of this location in degrees

open fun getSpeed(): Float

returns the speed at the time of this location in meters/second

open fun getExtras(): Bundle?

returns an optional bundle of additional information associated
with this location

LocationServices

main entry point for location services integration

FusedLocationProviderClient

main entry point for interacting with the fused location provider

LocationRequest

contains quality-of-service parameters for requests to the fused
location provider

LocationCallback

used for receiving notifications from the fused location provider

fused location provider

combines different signals to provide location information while optimizing the device’s use of battery power, r manages the underlying location technologies, such as GPS and Wi-Fi, and provides a simple API that can be used to specify the required quality of service

getFusedLocationProviderClient()

can be used to obtain a reference to a FusedLocationProviderClient object

getLastLocation()

gets a location estimate more quickly and minimizes battery usage, but the location information might be out of date if no other clients have actively used location recently

getCurrentLocation()

gets a fresher, more accurate location more consistently.

Geocoding

the process of transforming a street address or other description of a location into a (latitude, longitude) coordinate

Reverse geocoding

the process of transforming a (latitude, longitude) coordinate into a street address

Geocoder

handles geocoding and reverse geocoding, requires a backend service that is not included in the core android framework.