Tell the application whether the provider has been

Tell the application whether the provider has been disabled or enabled
• Give the status about the provider (such as the number of satellites the GPS receiver can see),
• Tell the application location information
public void onLocationChanged(Location location) {
String locInfo = String.
format("Current loc = (%f, %f) @ (%f meters up)",
location.getLatitude(), location.getLongitude(),
location.getAltitude() );
if (lastLocation != null) {
float distance = location.distanceTo(lastLocation);
locInfo += String.
format("\n Distance from last = %f meters", distance);
}
lastLocation = location;
status.setText(locInfo);
}

Locating Your Emulator
• The Android emulator can simulate location services, but as you would
expect, it does not have any “underlying hardware” to get a real satellite
fix.
• The Android SDK provides a means to simulate location data with the use
of a single location point, GPX file, or KML file.
• This works only with the emulator, not the physical device, but it can be
useful for testing your location-based application.
From Advanced Android
TM
Application Development, Fourth
Edition , by Joseph Annuzzi, Jr.,
Lauren Darcey, and Shane Conder
(ISBN-13: 978-0-13-389238-3).
Copyright © 2015 Joseph Annuzzi,

Geocoding Locations
• Determining latitude and longitude is useful for precise location, tracking,
and measurements.
– not usually descriptive to users.
• The Android SDK provides some helper methods to turn raw location data
into addresses and descriptive place names.
• These methods can also work in reverse, turning place names or
addresses into raw location coordinates, which is referred to as reverse
geocoding.

Geocoding Locations
• Geocoder object doesn’t need any special permission.
if (Geocoder.isPresent()) {
Geocoder coder = new Geocoder(this);
try {
List<Address> addresses = coder.getFromLocation(
location.getLatitude(), location.getLongitude(), 3);
if (addresses != null) {
for (Address namedLoc : addresses) {
String placeName = namedLoc.getLocality();
String featureName = namedLoc.getFeatureName();
String country = namedLoc.getCountryName();
String road = namedLoc.getThoroughfare();
locInfo.append(String.format("[%s][%s][%s][%s]\n",
placeName, featureName, road, country));
….
Location is passed in to
The onLocationChanged()

Geocoding Locations
….
int addIdx = namedLoc. getMaxAddressLineIndex ();
for (int idx = 0; idx <= addIdx; idx++) {
String addLine = namedLoc. getAddressLine (idx);
locInfo.append(String.format("Line %d: %s\n", idx,
addLine));
}
}
}
} catch (IOException e) {
Log.e("GPS", "Failed to get address", e);
}
} else {
Toast.makeText(GPSActivity.this, "No geocoding available",
Toast.LENGTH_LONG).show();
}

Geocoding Locations

Geocoding Locations
public void onClick(View v) {
if (Geocoder.isPresent()) {
String placeName = name.getText().toString();
try {
// coder initialized elsewhere
List<Address> geocodeResults = coder
.getFromLocationName(placeName, 3);
StringBuilder locInfo = new StringBuilder("Results:\n");
double lat = 0f;
double lon = 0f;
….

Geocoding Locations
….