I am trying to develop little application which at startup shows the name of current location in a toast or something. The code I wrote will show a Toast on the display with the location only is I send the coordinates manually from the Emulator Control View from Eclipse.
My question: Is there a way to force somehow this sending of coordinates at the startup, because I want that Toast when the application is loaded? And how can I do it? Thanks.
Here is the code:
public class HomeActivity extends Activity implements LocationListener {
private LocationManager locationManager;
private String welcomeMsg;
private String crtLocationName;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
initLocationManager();
}
private void initLocationManager(){
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 5000, this);
}
*/
#Override
public void onLocationChanged(Location location) {
if (location != null) {
try {
crtLocationName = getLocationName(location);
Toast.makeText( getApplicationContext(), crtLocationName, Toast.LENGTH_LONG).show();
} catch (IOException e) {
welcomeMsg = "Location cannot be determined";
crtLocationName = "";
}
// locationManager.removeUpdates(this);
}
}
#Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
}
As Emulator doesn't have a GPS receiver, the method onLocationChanged will be only invoked when you give some new coordinates through DDMS.
On the real phone, it will not show a Toast instantly; it will wait before it locates the GPS satellite and receive a GPS fix, then it will show the Toast message.
Related
I have an activity which uses onLocationChanged method and upon performing a parse query it makes a toast. It works fine. However, when I go to another activity (it's a maps activity), if I change the coordinates (I'm using an emulator) the toast pops up. I would like to know why the onLocationChanged method is still running. I thought it may be due to context, but I specified the activity in the context field.
locationManager = (LocationManager) DriverChoicesActivity.this.getSystemService(Context.LOCATION_SERVICE);
locationListener = new LocationListener() {
#Override
public void onLocationChanged(final Location location) {
final ParseGeoPoint parseGeoPoint = new ParseGeoPoint(location.getLatitude(), location.getLongitude());
ParseQuery<ParseUser> query = ParseUser.getQuery();
query.whereEqualTo("username", ParseUser.getCurrentUser().getUsername());
query.findInBackground(new FindCallback<ParseUser>() {
#Override
public void done(List<ParseUser> objects, ParseException e) {
if (e == null && objects.size() > 0) {
for (ParseObject object : objects) {
object.put("driverLocation", parseGeoPoint);
object.saveInBackground();
Toast.makeText(DriverChoicesActivity.this, "User found", Toast.LENGTH_SHORT).show();
}
}
}
});
updateRequestList(location);
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
};
All that is within onCreate of the original activity (DriverChoicesActivity.class). The other activity (DriverMapActivity.class) has no code in it apart from getting the intent from this activity to collect some latitude and longitude points. Here is the code which makes the intent (also within onCreate)
requestListView.setAdapter(arrayAdapter);
requestListView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
if (requestLatitude.size() > position && requestLongitude.size() > position) {
if (Build.VERSION.SDK_INT < 23 || ContextCompat.checkSelfPermission(DriverChoicesActivity.this, Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
Location getLastKnownLocation = locationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if (getLastKnownLocation != null) {
Intent intent = new Intent(getApplicationContext(), DriverMapActivity.class);
intent.putExtra("requestLatitude", requestLatitude.get(position));
intent.putExtra("requestLongitude", requestLongitude.get(position));
intent.putExtra("driverLatitude", getLastKnownLocation.getLatitude());
intent.putExtra("driverLongitude", getLastKnownLocation.getLongitude());
startActivity(intent);
}
}
}
}
});
I assume my problem is with context somehow. If someone could be kind enough to explain.
Thank you
You must add:
locationManager.removeUpdates(listener);
Before move to next Activity.
and
LocationManager locationManager;
LocationListener locationListener;
on the top, under class declaraction
Background:
Create an app that will center on the user's location and allow for them to text their location to contacts. To do this, we need a simple credential check and server address to test on in the preferences.
Issue:
Whenever the user navigates from the original map fragment that shows their location with a marker, the proper map type (hybrid), etc. to another fragment and then wants to return to the map fragment, it defaults to LatLng 0,0 and a generic map (no indication of user location for example).
My initial thought was to try and save the state of the map fragment upon switching to another fragment and reload that when popping the other fragment from the stack. However I then thought it might be simpler to just replace the current fragment in the MainActivity whenever I need to switch. So on opening the app, MainActivity creates a new MapFragment then replaces it with a Preferences Fragment and when 'saving' creates a new MapFragment to replace the current fragment with. Thought this might fix my problem as on initial load the map functions like I want.
The code for MFragment that contains the Map Fragment:
public class MFragment extends Fragment implements android.location.LocationListener,
GooglePlayServicesClient.ConnectionCallbacks,
GooglePlayServicesClient.OnConnectionFailedListener{
private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 9000;
private static GoogleMap map;
private static LocationClient lClient;
private final static String TAG = "MFragment";
private String provider;
private Location loc;
private LocationManager lManager;
private LatLng currentLatLng;
private final long MIN_TIME = 1000;
private final float MIN_DIST = 10;
private Update updateMarkers = new Update();
private View view;
private MapFragment mFrag;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
mFrag = MapFragment.newInstance();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
//sets the layout for this fragment
view = inflater.inflate(R.layout.fragment_map, container, false);
//insert MapFragment into this Fragment
getActivity().getFragmentManager().beginTransaction()
.replace(R.id.mapview, mFrag)
.commit();
//get a handle on the map from the MapFragment
// map = mFrag.getMap();
//instantiates the location manager
lManager = (LocationManager) getActivity().getSystemService(Context.LOCATION_SERVICE);
//instantiate the location client
lClient = new LocationClient(getActivity(), this, this);
lClient.connect();
//run through initialization of all objects
setUpMapIfNeeded();
Log.d(TAG, "Successfully created MFragment");
return view;
}
/**
* instantiates map from the MapFragment if map is null.
*/
private void setUpMapIfNeeded() {
if (getActivity() != null && getActivity().getFragmentManager() != null &&
map == null) {
map = mFrag.getMap();
Log.d(TAG, "Map generated.");
setUpMap();
} else if (lClient.isConnected()) {
updateMap();
} else {
setUpMap();
}
}
/**
* sets up the location data for the map. conditional clause so that the GPS doesn't crash
* if the app can't get a location straight away.
*/
private void setUpMap() {
if (map != null) {
map.setMyLocationEnabled(true);
map.setMapType(GoogleMap.MAP_TYPE_HYBRID);
Criteria crit = new Criteria();
provider = lManager.getBestProvider(crit, false);
if (lManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
loc = lManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
} else {
loc = lManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
}
lManager.requestLocationUpdates(provider, MIN_TIME, MIN_DIST, this);
}
}
protected void updateMap() {
if (servicesConnected()) {
map.clear();
currentLatLng = new LatLng(this.loc.getLatitude(), this.loc.getLongitude());
map.animateCamera(CameraUpdateFactory.newLatLngZoom(currentLatLng, 14));
map.addMarker(new MarkerOptions()
.position(currentLatLng)
.title("You"));
map.setOnMarkerClickListener(new OnMarkerClickListener() {
#Override
public boolean onMarkerClick(Marker m) {
SMSFragment sFrag = new SMSFragment();
sFrag.setMarker(m);
getActivity().getFragmentManager().beginTransaction()
.replace(android.R.id.content, sFrag)
.commit();
return false;
}
});
}
}
/**
* checks for connection to google play services
* #return
*/
private boolean servicesConnected() {
int resultCode = GooglePlayServicesUtil
.isGooglePlayServicesAvailable(getActivity().getApplicationContext());
if (ConnectionResult.SUCCESS == resultCode) {
Log.d(TAG, getString(R.string.play_available));
return true;
} else {
if (GooglePlayServicesUtil.isUserRecoverableError(resultCode)) {
GooglePlayServicesUtil
.getErrorDialog(resultCode, getActivity(),
CONNECTION_FAILURE_RESOLUTION_REQUEST).show();
} else {
Log.i(TAG, "This device is not supported");
}
return false;
}
}
#Override
public void onConnectionFailed(ConnectionResult connectionResult) {
if (connectionResult.hasResolution()) {
try {
connectionResult
.startResolutionForResult(getActivity(), CONNECTION_FAILURE_RESOLUTION_REQUEST);
} catch (IntentSender.SendIntentException e) {
e.printStackTrace();
}
} else {
Toast.makeText(getActivity(), R.string.connect_failed, Toast.LENGTH_SHORT).show();
}
}
/**
* Called after location client connects
*/
#Override
public void onConnected(Bundle arg0) {
updateMap();
}
/**
* simple display message after disconnecting.
*/
#Override
public void onDisconnected() {
Toast.makeText(getActivity(), R.string.disconnected, Toast.LENGTH_SHORT).show();
}
public void onStart() {
super.onStart();
lClient.connect();
setUpMapIfNeeded();
}
public void onResume() {
super.onResume();
lClient.connect();
setUpMapIfNeeded();
}
public void onPause() {
lClient.disconnect();
super.onPause();
}
public void onStop() {
lClient.disconnect();
super.onStop();
}
public void onDestroy() {
lClient.disconnect();
super.onDestroy();
}
#Override
public void onLocationChanged(Location location) {
this.loc = location;
updateMap();
}
#Override
public void onProviderDisabled(String provider) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String provider) {
// TODO Auto-generated method stub
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
// TODO Auto-generated method stub
}
public void updateMarkers(List<Record> records){
//update map with markers corresponding to each latitude, longitude passed back from records
for (Record r : records){
map.addMarker( new MarkerOptions()
.position(new LatLng(r.getValueOfLatitude(), r.getValueOfLongitude())));
}
}
private class Update extends AsyncTask<Void, Void, Boolean> {
private List<Record> records;
protected Update() {
super();
records = new ArrayList<Record>();
}
#Override
protected Boolean doInBackground(Void... params) {
Connect conn = new Connect(getActivity());
try {
records = conn.getAll();
return true;
} catch (IOException e) {
e.printStackTrace();
}
return false;
}
protected void onPostExecute(Boolean result) {
if (result) {
updateMarkers(records);
} else {
Toast.makeText(getActivity(), R.string.rec_fail, Toast.LENGTH_SHORT).show();
}
}
}
}
And an example of replacing the Fragment from another Fragment (From PrefsFragment to MFragment):
register = (Button) v.findViewById(R.id.register);
save.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
saveToPreferences(v);
((MainActivity)getActivity()).replaceFragment();
}
});
register.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
getActivity().getFragmentManager().beginTransaction()
.replace(android.R.id.content, new RegFragment())
.commit();
}
});
return v;
}
the save button calls a method in MainActivity to replace the current fragment with a MapFragment as an attempted work-around but doesn't function like I was hoping and using the similar method for the register button using FragmentManager doesn't fix the Map issue either.
Any help is appreciated.
Don't put a fragment inside another fragment unless you really need to. If you choose to do so, you may not use the FragmentManager of the Activity like you do. Instead you must use the child fragment manager of the container fragment to create the fragment transaction that will insert the child fragment by calling getChildFragmentManager().
This is supported since API level 17 (Android 4.2) or using the most recent Android Support Library. I suggest you to always use the support library by default.
I am writting code for getting current location (latitude and longitude) of my phone. I display a toast whether Network Location service is provided by the phone or not. This toast doesn't show up ever. The other question is, for getting current location using Network_location, will the app use phone's gprs/internet or not?
I have created the instance of this class in the main activity and then get data using Latitude and Longitude variables of this class, in another class which extends broadcast reciever .
public class GpsClass extends Activity{
public static String Latitude="";
public static String Longitude="";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
LocationManager manager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
LocationListener listener = new LocationListener() { // anonymous class
#Override
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {
// TODO Auto-generated method stub
}
#Override
public void onProviderEnabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onProviderDisabled(String arg0) {
// TODO Auto-generated method stub
}
#Override
public void onLocationChanged(Location currentLocation) {
double lat= currentLocation.getLatitude();
Latitude = Double.toString(lat);
double longt= currentLocation.getLongitude();
Longitude = Double.toString(longt);
}
};
manager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 0, 0, listener);
if(manager.isProviderEnabled(LocationManager.NETWORK_PROVIDER))
{
Toast.makeText(getApplicationContext(), "Network enabled", 0).show();
}
else
Toast.makeText(getApplicationContext(), "Network not enabled", 0).show();
}
}
Is there anything I am doing wrong?
Regards
I think the problem is that you are passing 0 for duration i.e. last parameter of makeText() method.
Try passing Toast.LENGTH_SHORT or Toast.LENGTH_LONG.
if(manager.isProviderEnabled(LocationManager.NETWORK_PROVIDER))
{
Toast.makeText(getApplicationContext(), "Network enabled", Toast.LENGTH_LONG).show();
}
else
Toast.makeText(getApplicationContext(), "Network not enabled", Toast.LENGTH_LONG).show();
This can help you to get answer to your first question.
The answer to your second question is - No, the app will not use phone's gprs/internet for getting location through network provider.
The problem is setting 0 for duration.
This is a sample example:
locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
locationListener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
currentLocation = new GeoPoint(location.getLatitude(), location.getLongitude());
// Set Toast Here To Diplay location
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
}
#Override
public void onProviderEnabled(String provider) {
}
#Override
public void onProviderDisabled(String provider) {
}
};
if (locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
//10000 means request update every 10 sec
//10 tell listener that if location change more than 10m then run locationChanged method
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 10000, 10, locationListener);
} else {
locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 10000, 10, locationListener);
}
I am new to android, and reverse-engineering my way into learning java.
Having got as far using the code below, i have a few problems needing to be resolved while customising it to suit my inentions.
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
/* Use the LocationManager class to obtain GPS locations */
LocationManager mlocManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
LocationListener mlocListener = new MyLocationListener();
mlocManager.requestLocationUpdates( LocationManager.GPS_PROVIDER, 0, 0, mlocListener);
}
/* Class My Location Listener */
public class MyLocationListener implements LocationListener
{
#Override
public void onLocationChanged(Location loc)
{
loc.getLatitude();
loc.getLongitude();
String Text = “My current location is: “ +
“Latitud = “ + loc.getLatitude() +
“Longitud = “ + loc.getLongitude();
Toast.makeText( getApplicationContext(),
Text,
Toast.LENGTH_SHORT).show();
}
#Override
public void onProviderDisabled(String provider)
{
Toast.makeText( getApplicationContext(),
“Gps Disabled”,
Toast.LENGTH_SHORT ).show();
}
#Override
public void onProviderEnabled(String provider)
{
Toast.makeText( getApplicationContext(),
“Gps Enabled”,
Toast.LENGTH_SHORT).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras)
{
The problem is my (android) home screen starts with a checkboxed page showing two choices (checboxes);
GPS On (Enabled)
GPS Off (Disabled)
Now, question is, i have no idea how to write the 'if else' statement/method which could which could help direct the 'On' scenario to the next stage of getting my location, and for directing the 'Off' scenario back to beginning (Home screen).
Where/how in the code do i declare/insert the checkbox code?
Any assistance welcome please.
Thanks
Basic checkbox check:
final CheckBox cbGPS = (CheckBox) findViewById(R.id.checkBox1);
cbGPS.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView,boolean isChecked) {
// TODO Auto-generated method stub
if (buttonView.isChecked()) {
// do this if checked
StartGPSMethod();
} else {
// if not checked do this
// do nothing or
EndGPSMethod();
}
}
});
Is there a way to access the GPS once instead of having a looper that constantly checks for location updates?
In my scenario all I'm interested in is finding the current co-ordinates and not a continuous connection with the GPS satellite. Does anyone have any ideas how this can be done? Thanks in advance.
Dont use the getLastKnownLocation because that could be returning null or old data.
This code Only fetches the location once a button is pressed and not every time. People use to leave the location listener listen in every instance and that kills the battery life so Use the code snippet I have posted by doing lots of research:
// get the text view and buttons from the xml layout
Button button = (Button) findViewById(R.id.btnGetLocation);
final TextView latitude = (TextView) findViewById(R.id.textview4);
final TextView longitude = (TextView) findViewById(R.id.textview5);
final LocationListener locationListener = new LocationListener() {
#Override
public void onLocationChanged(Location location) {
mlocation = location;
Log.d("Location Changes", location.toString());
latitude.setText(String.valueOf(location.getLatitude()));
longitude.setText(String.valueOf(location.getLongitude()));
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Log.d("Status Changed", String.valueOf(status));
}
#Override
public void onProviderEnabled(String provider) {
Log.d("Provider Enabled", provider);
}
#Override
public void onProviderDisabled(String provider) {
Log.d("Provider Disabled", provider);
}
};
// Now first make a criteria with your requirements
// this is done to save the battery life of the device
// there are various other other criteria you can search for..
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
criteria.setPowerRequirement(Criteria.POWER_LOW);
criteria.setAltitudeRequired(false);
criteria.setBearingRequired(false);
criteria.setSpeedRequired(false);
criteria.setCostAllowed(true);
criteria.setHorizontalAccuracy(Criteria.ACCURACY_HIGH);
criteria.setVerticalAccuracy(Criteria.ACCURACY_HIGH);
// Now create a location manager
final LocationManager locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
// This is the Best And IMPORTANT part
final Looper looper = null;
// Now whenever the button is clicked fetch the location one time
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
locationManager.requestSingleUpdate(criteria, locationListener, looper);
}
});
First check if the last know location is recent. If not, I believe you must to set up onLocationChanged listener, but once you get your first valid location you can always stop the stream of updates.
Addition
public class Example extends Activity implements LocationListener {
LocationManager mLocationManager;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mLocationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
Location location = mLocationManager.getLastKnownLocation(LocationManager.GPS_PROVIDER);
if(location != null && location.getTime() > Calendar.getInstance().getTimeInMillis() - 2 * 60 * 1000) {
// Do something with the recent location fix
// otherwise wait for the update below
}
else {
mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, 0, 0, this);
}
}
public void onLocationChanged(Location location) {
if (location != null) {
Log.v("Location Changed", location.getLatitude() + " and " + location.getLongitude());
mLocationManager.removeUpdates(this);
}
}
// Required functions
public void onProviderDisabled(String arg0) {}
public void onProviderEnabled(String arg0) {}
public void onStatusChanged(String arg0, int arg1, Bundle arg2) {}
}