Develop Reference

ensure location accuracy and track user on Google map

My android application function is to track the user location when it walk/run or when he never moves(then location should not change)First, the location is inaccurate and red marker keeps popping out on the map even if i never move. the position where it pops out is also inaccurate.
For those who did similar location tracking app before, the blue dot should be the same place as the latest red marker right? but my blue dot is always away most of the time. red marker shows a more accurate position(although still inaccurate)
i have tested it in my house, outside, in a vehicle. when it is in my house, sometimes location keeps changing, sometimes location never change. i cannot predict it. usually gps don't work well in-house so i leave it first
when i test it outside, sometimes it is better but it is still inaccurate. when i never move/move or move slow it update on the wrong location. althought it is sometimes little better then in roof. but in the end it is still unuseable.
when i test it in the car, it is better as it won't pop out so much location should be more accurate blue dot and red marker are sometimes together. although there are still inaccurate sometimes. but it does not matter as my app is supposed to use when the user is walking/running not in a moving vehicle.
for all three, red marker appears(no matter how frequently) around the correct environment(house, road, certain building) sometimes, but the blue dot is not, most of the times it is wrong. but i wanted the blue dot as a tracker for the user. user would not know which red marker is his current location even if it is accurate. the title "you are here" could appear on any marker when i tap on it, where it is new or old. so it is not effective. and when a new one appear, the title does not appear by itself.
the problem i am trying to solve is to ensure location accuracy, even if not good or perfect at lease be useable, and have the blue dot track the user continuously,or red marker as long as sometimes tell the where is he accurately(title only appears on the latest marker by itself).
i am research for a long time and i do not know what else i can implement to make it more accurate. the distance calculation i believe should be accurate but it depends on the location so it will becomes inaccurate too. sorry for the large text i just thought i should explain myself clearer...
public class MainActivity extends FragmentActivity implements LocationListener{
protected LocationManager locationManager;
private GoogleMap googleMap;
Button btnStartMove,btnPause,btnResume,btnStop;
static double n=0;
Long s1,r1;
double dis=0.0;
Thread t1;
EditText userNumberInput;
boolean bool=false;
int count=0;
double speed = 1.6;
double lat1,lon1,lat2,lon2,lat3,lon3,lat4,lon4;
double dist = 0.0;
double time = 0.0;
double velocity = 0.0;
TextView distance;
Button btnDuration;
float[] result;
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES =1; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 4000; //in milliseconds
boolean startDistance = false;
boolean startButtonClicked = false;
MyCount counter;
int timer = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
if(isGooglePlay())
{
setUpMapIfNeeded();
}
distance=(TextView)findViewById(R.id.Distance);
btnDuration=(Button)findViewById(R.id.Duration);
btnStartMove=(Button)findViewById(R.id.Start);//start moving
btnStop=(Button)findViewById(R.id.Stop);
//prepare distance...........
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
btnStartMove.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
lat3 = location.getLatitude();
lon3 = location.getLongitude();
startButtonClicked=true;
startDistance=true;
counter= new MyCount(30000,1000);
counter.start();
btnStartMove.setText("Started...");
}
});
btnStop.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
startButtonClicked=false;
startDistance=false;
//Double.valueOf(distance.getText().toString()
Double value=dist;
Double durationValue=time;
Double speedValue=velocity;
Intent intent = new Intent(MainActivity.this, FinishActivity.class);
intent.putExtra("dist", value);
intent.putExtra("time",durationValue);
intent.putExtra("velocity",speedValue);
startActivity(intent);
counter.cancel();
n=0;
r1=null;
time=0.0;
btnStartMove.setText("Start Move");
finish();
}
});
btnDuration.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
if(startButtonClicked=true)
{
time=n*30+r1;
velocity=dist/time;
DecimalFormat df = new DecimalFormat("#.##");
Toast.makeText(MainActivity.this,"Duration :"+String.valueOf(time) + "Speed :"+String.valueOf(df.format(velocity)),Toast.LENGTH_LONG).show();
}
}
});
if(location!= null)
{
//Display current location in Toast
String message = String.format(
"Current Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude()
);
Toast.makeText(MainActivity.this, message,
Toast.LENGTH_LONG).show();
}
else if(location == null)
{
Toast.makeText(MainActivity.this,
"Location is null",
Toast.LENGTH_LONG).show();
}
}
private void setUpMapIfNeeded() {
if(googleMap == null)
{
googleMap =((SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.displayMap)).getMap();
if(googleMap != null)
{
setUpMap();
}
}
}
private void setUpMap()
{
//Enable MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
//Get locationManager object from System Service LOCATION_SERVICE
//LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
//Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
//Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
if(provider == null)
{
onProviderDisabled(provider);
}
//set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
//Get current location
Location myLocation = locationManager.getLastKnownLocation(provider);
if(myLocation != null)
{
double latitude = myLocation.getLatitude();
//Get longitude of the current location
double longitude = myLocation.getLongitude();
//Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
//Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).snippet("You are here!").title("You are here!"));
}
locationManager.requestLocationUpdates(provider, 0, 0, this);
}
private boolean isGooglePlay()
{
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (status == ConnectionResult.SUCCESS)
{
Toast.makeText(MainActivity.this, "Google Play Services is available",
Toast.LENGTH_LONG).show();
return(true);
}
else
{
GooglePlayServicesUtil.getErrorDialog(status, this, 10).show();
}
return (false);
}
#Override
public void onLocationChanged(Location myLocation) {
System.out.println("speed " + myLocation.getSpeed());
//show location on map.................
//Get latitude of the current location
double latitude = myLocation.getLatitude();
//Get longitude of the current location
double longitude = myLocation.getLongitude();
//Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
//Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).snippet("You are here!").title("You are here!"));
//show distance............................
if(startDistance == true)
{
Toast.makeText(MainActivity.this,
"Location has changed",
Toast.LENGTH_LONG).show();
if(myLocation != null)
{
//latitude.setText("Current Latitude: " + String.valueOf(loc2.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(loc2.getLongitude()));
float[] results = new float[1];
Location.distanceBetween(lat3, lon3, myLocation.getLatitude(), myLocation.getLongitude(), results);
System.out.println("Distance is: " + results[0]);
dist += results[0];
DecimalFormat df = new DecimalFormat("#.##"); // adjust this as appropriate
if(count==1)
{
distance.setText(df.format(dist) + "meters");
}
lat3=myLocation.getLatitude();
lon3=myLocation.getLongitude();
count=1;
}
}
if(startButtonClicked == true)
{
startDistance=true;
}
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider disabled by the user. GPS turned off",
Toast.LENGTH_LONG).show();
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider enabled by the user. GPS turned on",
Toast.LENGTH_LONG).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Toast.makeText(MainActivity.this, "Provider status changed",
Toast.LENGTH_LONG).show();
}
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
}
public class MyCount extends CountDownTimer{
public MyCount(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onFinish() {
counter= new MyCount(30000,1000);
counter.start();
n=n+1;
}
#Override
public void onTick(long millisUntilFinished) {
s1=millisUntilFinished;
r1=(30000-s1)/1000;
}
}}

0.0 value when data pass over from First Activity to Next(Android)

i wanted to pass my distance and duration over to the next page, but the result display is 0.0 for both
first Activity
btnStop.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
startButtonClicked=false;
startDistance=false;
Double value=Double.valueOf(distance.getText().toString());
Double durationValue=time;
Intent intent = new Intent(MainActivity.this, FinishActivity.class);
intent.putExtra("dist", value);
intent.putExtra("time",durationValue);
startActivity(intent);
finish();
}
});
at the Activity where it display
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_finish);
Bundle extras = getIntent().getExtras();
if (extras != null)
{
Double value = extras.getDouble("dist");
Double durationValue = extras.getDouble("time");
displayDistance=(TextView)findViewById(R.id.finishDistance);
displayDistance.setText("Distance: " + value);
displayDuration=(TextView)findViewById(R.id.finishDuration);
displayDuration.setText("Duration: " + durationValue);
}
the app crash after i presses stopped
here is my full Java code for the first Activity(second just display them). in case you all want to see how i get them
public class MainActivity extends FragmentActivity implements LocationListener{
protected LocationManager locationManager;
private GoogleMap googleMap;
Button btnStartMove,btnPause,btnResume,btnStop;
static double n=0;
Long s1,r1;
double dis=0.0;
Thread t1;
EditText userNumberInput;
boolean bool=false;
int count=0;
double speed = 1.6;
double lat1,lon1,lat2,lon2,lat3,lon3,lat4,lon4;
double dist = 0;
TextView distance;
Button btnDuration;
float[] result;
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES =1; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 4000; //in milliseconds
boolean startDistance = false;
boolean startButtonClicked = false;
MyCount counter;
int timer = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
if(isGooglePlay())
{
setUpMapIfNeeded();
}
distance=(TextView)findViewById(R.id.Distance);
btnDuration=(Button)findViewById(R.id.Duration);
btnStartMove=(Button)findViewById(R.id.Start);//start moving
btnStop=(Button)findViewById(R.id.Stop);
//prepare distance...........
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
btnStartMove.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
lat3 = location.getLatitude();
lon3 = location.getLongitude();
startButtonClicked=true;
counter= new MyCount(30000,1000);
counter.start();
Toast.makeText(MainActivity.this,
"start is true",
Toast.LENGTH_LONG).show();
}
});
btnStop.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
startButtonClicked=false;
startDistance=false;
//String dis = (String) distance.getText();
//Double dd = Double.parseDouble(dis);
Intent intent = new Intent(MainActivity.this, FinishActivity.class);
//DecimalFormat df = new DecimalFormat("#.##");
//dist=(df.format(dd);
intent.putExtra("dist","value");
//intent.putExtra("speed","speedValue");
intent.putExtra("time","durationValue");
startActivity(intent);
finish();
}
});
btnDuration.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
if(startButtonClicked=true)
{
double time=n*30+r1;
Toast.makeText(MainActivity.this,"Speed(m/s) :"+String.valueOf(dist/time)+"Duration :"+String.valueOf(time),Toast.LENGTH_LONG).show();
}
}
});
if(location!= null)
{
//Display current location in Toast
String message = String.format(
"Current Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude()
);
Toast.makeText(MainActivity.this, message,
Toast.LENGTH_LONG).show();
//Display current location in textview
//latitude.setText("Current Latitude: " + String.valueOf(location.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(location.getLongitude()));
}
else if(location == null)
{
Toast.makeText(MainActivity.this,
"Location is null",
Toast.LENGTH_LONG).show();
}
}
private void setUpMapIfNeeded() {
if(googleMap == null)
{
Toast.makeText(MainActivity.this, "Getting map",
Toast.LENGTH_LONG).show();
googleMap =((SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.displayMap)).getMap();
if(googleMap != null)
{
setUpMap();
}
}a
}
private void setUpMap()
{
//Enable MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
//Get locationManager object from System Service LOCATION_SERVICE
//LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
//Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
//Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
if(provider == null)
{
onProviderDisabled(provider);
}
//set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
//Get current location
Location myLocation = locationManager.getLastKnownLocation(provider);
if(myLocation != null)
{
onLocationChanged(myLocation);
}
locationManager.requestLocationUpdates(provider, 0, 0, this);
}
private boolean isGooglePlay()
{
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (status == ConnectionResult.SUCCESS)
{
Toast.makeText(MainActivity.this, "Google Play Services is available",
Toast.LENGTH_LONG).show();
return(true);
}
else
{
GooglePlayServicesUtil.getErrorDialog(status, this, 10).show();
}
return (false);
}
#Override
public void onLocationChanged(Location myLocation) {
System.out.println("speed " + myLocation.getSpeed());
//show location on map.................
//Get latitude of the current location
double latitude = myLocation.getLatitude();
//Get longitude of the current location
double longitude = myLocation.getLongitude();
//Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
//Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!"));
//show distance............................
if(startDistance == true)
{
Toast.makeText(MainActivity.this,
"Location has changed",
Toast.LENGTH_LONG).show();
if(myLocation != null)
{
//latitude.setText("Current Latitude: " + String.valueOf(loc2.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(loc2.getLongitude()));
float[] results = new float[1];
Location.distanceBetween(lat3, lon3, myLocation.getLatitude(), myLocation.getLongitude(), results);
System.out.println("Distance is: " + results[0]);
dist += results[0];
DecimalFormat df = new DecimalFormat("#.##"); // adjust this as appropriate
if(count==1)
{
distance.setText(df.format(dist) + "meters");
}
lat3=myLocation.getLatitude();
lon3=myLocation.getLongitude();
count=1;
}
}
if(startButtonClicked == true)
{
startDistance=true;
}
//}
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider disabled by the user. GPS turned off",
Toast.LENGTH_LONG).show();
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider enabled by the user. GPS turned on",
Toast.LENGTH_LONG).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Toast.makeText(MainActivity.this, "Provider status changed",
Toast.LENGTH_LONG).show();
}
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
}
public class MyCount extends CountDownTimer{
public MyCount(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onFinish() {
counter= new MyCount(30000,1000);
counter.start();
n=n+1;
}
#Override
public void onTick(long millisUntilFinished) {
s1=millisUntilFinished;
r1=(30000-s1)/1000;
//e1.setText(String.valueOf(r1));
}
}}

Here is your problem: You are passing string values through intent when you expect the doubles in your second...
Intent intent = new Intent(MainActivity.this, FinishActivity.class);
intent.putExtra("dist","value");
intent.putExtra("time","durationValue");
startActivity(intent);

[EDIT] I assume you have 2 EditTexts to allow the user to enter the data. Lets say they are editText1 &editText2.
The EditTexts hold Strings so you need to convert/cast them.
Double value=Double.valueOf(editText1.getText().toString());
Double durationValue=Double.valueOf(editText2.getText().toString());
Also Make sure that you enter only digits in the EditTexts.
In your FirstActivity you are passing Strings instead of Doubles.
So instead of that you should use it like this:
intent.putExtra("dist",value);
intent.putExtra("time",durationValue);
Just omit the double Quotes " ".
notice that value and durationValue are must be Doubles in your code.
Hope it Helps.

wrong location on Google Map. cannot retrieve correct distance to next Activity

My android app is to track user location on a map and calculate the distance and duration he has walked or run. Then when i press stop, pass it over to the next page.
My distance and duration calculation should be correct, but the location is wrong. whether i don't move or move a few meters in my house, it sometimes never change or change a lot, result in the distance being inaccurate. how do i ensure accuracy for when i walked, even a few meters, because when i present i will be walking for a short distance.
second, i can pass my duration data over to the next page, but when i pass my distance it is 0.0 but the value shown is not 0.0 at all(got value although inaccurate). i pass my information when i press Stop button.
My MainActivity Java Code, display map, distance, duration.
protected LocationManager locationManager;
private GoogleMap googleMap;
Button btnStartMove,btnPause,btnResume,btnStop;
static double n=0;
Long s1,r1;
double dis=0.0;
Thread t1;
EditText userNumberInput;
boolean bool=false;
int count=0;
double speed = 1.6;
double lat1,lon1,lat2,lon2,lat3,lon3,lat4,lon4;
double dist = 0.0;
double time = 0.0;
TextView distance;
Button btnDuration;
float[] result;
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES =1; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 4000; //in milliseconds
boolean startDistance = false;
boolean startButtonClicked = false;
MyCount counter;
int timer = 0;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
if(isGooglePlay())
{
setUpMapIfNeeded();
}
distance=(TextView)findViewById(R.id.Distance);
btnDuration=(Button)findViewById(R.id.Duration);
btnStartMove=(Button)findViewById(R.id.Start);//start moving
btnStop=(Button)findViewById(R.id.Stop);
//prepare distance...........
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
btnStartMove.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
lat3 = location.getLatitude();
lon3 = location.getLongitude();
startButtonClicked=true;
startDistance=true;
counter= new MyCount(30000,1000);
counter.start();
Toast.makeText(MainActivity.this,
"Pressed Start",
Toast.LENGTH_LONG).show();
}
});
btnStop.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
startButtonClicked=false;
startDistance=false;
//Double.valueOf(distance.getText().toString()
Double value=dist;
Double durationValue=time;
Intent intent = new Intent(MainActivity.this, FinishActivity.class);
intent.putExtra("dist", "value");
intent.putExtra("time",durationValue);
startActivity(intent);
finish();
}
});
btnDuration.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
if(startButtonClicked=true)
{
time=n*30+r1;
Toast.makeText(MainActivity.this,"Duration :"+String.valueOf(time),Toast.LENGTH_LONG).show();
}
}
});
if(location!= null)
{
//Display current location in Toast
String message = String.format(
"Current Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude()
);
Toast.makeText(MainActivity.this, message,
Toast.LENGTH_LONG).show();
}
else if(location == null)
{
Toast.makeText(MainActivity.this,
"Location is null",
Toast.LENGTH_LONG).show();
}
}
private void setUpMapIfNeeded() {
if(googleMap == null)
{
Toast.makeText(MainActivity.this, "Getting map",
Toast.LENGTH_LONG).show();
googleMap =((SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.displayMap)).getMap();
if(googleMap != null)
{
setUpMap();
}
}
}
private void setUpMap()
{
//Enable MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
//Get locationManager object from System Service LOCATION_SERVICE
//LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
//Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
//Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
if(provider == null)
{
onProviderDisabled(provider);
}
//set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
//Get current location
Location myLocation = locationManager.getLastKnownLocation(provider);
if(myLocation != null)
{
onLocationChanged(myLocation);
}
locationManager.requestLocationUpdates(provider, 0, 0, this);
}
private boolean isGooglePlay()
{
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (status == ConnectionResult.SUCCESS)
{
Toast.makeText(MainActivity.this, "Google Play Services is available",
Toast.LENGTH_LONG).show();
return(true);
}
else
{
GooglePlayServicesUtil.getErrorDialog(status, this, 10).show();
}
return (false);
}
#Override
public void onLocationChanged(Location myLocation) {
System.out.println("speed " + myLocation.getSpeed());
//show location on map.................
//Get latitude of the current location
double latitude = myLocation.getLatitude();
//Get longitude of the current location
double longitude = myLocation.getLongitude();
//Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
//Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!"));
//show distance............................
if(startDistance == true)
{
Toast.makeText(MainActivity.this,
"Location has changed",
Toast.LENGTH_LONG).show();
if(myLocation != null)
{
//latitude.setText("Current Latitude: " + String.valueOf(loc2.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(loc2.getLongitude()));
float[] results = new float[1];
Location.distanceBetween(lat3, lon3, myLocation.getLatitude(), myLocation.getLongitude(), results);
System.out.println("Distance is: " + results[0]);
dist += results[0];
DecimalFormat df = new DecimalFormat("#.##"); // adjust this as appropriate
if(count==1)
{
distance.setText(df.format(dist) + "meters");
}
lat3=myLocation.getLatitude();
lon3=myLocation.getLongitude();
count=1;
}
}
if(startButtonClicked == true)
{
startDistance=true;
}
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider disabled by the user. GPS turned off",
Toast.LENGTH_LONG).show();
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider enabled by the user. GPS turned on",
Toast.LENGTH_LONG).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Toast.makeText(MainActivity.this, "Provider status changed",
Toast.LENGTH_LONG).show();
}
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
}
public class MyCount extends CountDownTimer{
public MyCount(long millisInFuture, long countDownInterval) {
super(millisInFuture, countDownInterval);
}
#Override
public void onFinish() {
counter= new MyCount(30000,1000);
counter.start();
n=n+1;
}
#Override
public void onTick(long millisUntilFinished) {
s1=millisUntilFinished;
r1=(30000-s1)/1000;
}
}}
pass information to this page,distance 0.0(inaccurate) duration is ok
public class FinishActivity extends Activity {
TextView displayDistance;
TextView displayDuration;
TextView displaySports;
TextView userID;
TextView sportID;
TextView caloriesBurned;
Button back;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_finish);
Bundle extras = getIntent().getExtras();
if (extras != null)
{
Double value = extras.getDouble("dist");
Double durationValue = extras.getDouble("time");
displayDistance=(TextView)findViewById(R.id.finishDistance);
displayDistance.setText("Distance: " + value);
displayDuration=(TextView)findViewById(R.id.finishDuration);
displayDuration.setText("Duration: " + durationValue + " seconds");
}
back=(Button)findViewById(R.id.Back);
back.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
Intent intent = new Intent(FinishActivity.this, MainActivity.class);
startActivity(intent);
finish();
}
});}
My output for my map, inaccurate location. i search for long but there seem to be no solution for this..please help..thanks. the starting location, speed where it change location, all seem to be different each time i run. it appear to be out of my control(or i can but i do not know..i'm a beginner at gps... most of the time it needs to wait a while before displaying the distance.

Gps may not work well under the roof. So try it outside the house.
Also you have
intent.putExtra("dist", "value")
key is dist
value is a string not a double
SO you are passing string
But when you get you get the double
Double value = extras.getDouble("dist"); // wrong
If you pass a double value then you can get the double in the next activity. But you pass string and then you try to get the double value and that is wrong.
What you need
public Intent putExtra (String name, double value)
and
public double getDoubleExtra (String name, double defaultValue)

wierd location, distance output for maps using gps

after some time where i run my app, the distance remains 0 which is correct since i am not moving, but after 20-30 min in between it gain to 8-18 meters, i forgot. even more later, it grow to hundred. over time the marker gets more dispersed.
how can i pinpoint a location and if i never move, stop changing?
if i move, from my room to my living room, should be 4-7meters about i think, the distance never increase.
for those who done similar stuff before, does the blue dot and red marker goes together. my blue dot is not correct most of the time
i really do not know where i can improve my codes or what is the cause of the output..
My MainActivity File
public class MainActivity extends FragmentActivity implements LocationListener{
protected LocationManager locationManager;
private GoogleMap googleMap;
Button btnStartMove,btnPause,btnResume,btnStop;
static double n=0;
Long s1,r1;
double dis=0.0;
Thread t1;
EditText userNumberInput;
boolean bool=false;
int count=0;
double speed = 1.6;
double lat1,lon1,lat2,lon2,lat3,lon3,lat4,lon4;
double dist = 0;
TextView distanceText;
float[] result;
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES =1; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 4000; //in milliseconds
boolean startDistance = false;
boolean startButtonClicked = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
if(isGooglePlay())
{
setUpMapIfNeeded();
}
distanceText=(TextView)findViewById(R.id.Distance);
btnStartMove=(Button)findViewById(R.id.Start);//start moving
//prepare distance...........
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
btnStartMove.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
lat3 = location.getLatitude();
lon3 = location.getLongitude();
startButtonClicked=true;
Toast.makeText(MainActivity.this,
"start is true",
Toast.LENGTH_LONG).show();
}
});
if(location!= null)
{
//Display current location in Toast
String message = String.format(
"Current Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude()
);
Toast.makeText(MainActivity.this, message,
Toast.LENGTH_LONG).show();
//Display current location in textview
//latitude.setText("Current Latitude: " + String.valueOf(location.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(location.getLongitude()));
}
else if(location == null)
{
Toast.makeText(MainActivity.this,
"Location is null",
Toast.LENGTH_LONG).show();
}
}
private void setUpMapIfNeeded() {
if(googleMap == null)
{
Toast.makeText(MainActivity.this, "Getting map",
Toast.LENGTH_LONG).show();
googleMap =((SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.displayMap)).getMap();
if(googleMap != null)
{
setUpMap();
}
}
}
private void setUpMap()
{
//Enable MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
//Get locationManager object from System Service LOCATION_SERVICE
//LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
//Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
//Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
if(provider == null)
{
onProviderDisabled(provider);
}
//set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
//Get current location
Location myLocation = locationManager.getLastKnownLocation(provider);
if(myLocation != null)
{
onLocationChanged(myLocation);
}
locationManager.requestLocationUpdates(provider, 0, 0, this);
}
private boolean isGooglePlay()
{
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (status == ConnectionResult.SUCCESS)
{
Toast.makeText(MainActivity.this, "Google Play Services is available",
Toast.LENGTH_LONG).show();
return(true);
}
else
{
GooglePlayServicesUtil.getErrorDialog(status, this, 10).show();
}
return (false);
}
#Override
public void onLocationChanged(Location myLocation) {
System.out.println("speed " + myLocation.getSpeed());
// if(myLocation.getSpeed() > speed)//return 0 in actual
// {
//show location on map.................
//Get latitude of the current location
double latitude = myLocation.getLatitude();
//Get longitude of the current location
double longitude = myLocation.getLongitude();
//Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
//Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!"));
//show distance............................
if(startDistance == true)
{
Toast.makeText(MainActivity.this,
"Location has changed",
Toast.LENGTH_LONG).show();
if(myLocation != null)
{
//latitude.setText("Current Latitude: " + String.valueOf(loc2.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(loc2.getLongitude()));
float[] results = new float[1];
Location.distanceBetween(lat3, lon3, myLocation.getLatitude(), myLocation.getLongitude(), results);
System.out.println("Distance is: " + results[0]);
dist += results[0];
DecimalFormat df = new DecimalFormat("#.##"); // adjust this as appropriate
if(count==1)
{
distanceText.setText(df.format(dist) + "meters");
}
lat3=myLocation.getLatitude();
lon3=myLocation.getLongitude();
count=1;
}
}
if(startButtonClicked == true)
{
startDistance=true;
}
//}
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider disabled by the user. GPS turned off",
Toast.LENGTH_LONG).show();
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider enabled by the user. GPS turned on",
Toast.LENGTH_LONG).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Toast.makeText(MainActivity.this, "Provider status changed",
Toast.LENGTH_LONG).show();
}
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
}}
i tried changing the min time and distance to all sorts of data and it remains the same. i never really move my phone most of the time in the above output. one time i move out for short while but distance did not increase. for those that done similar running app, which part do i need to change..i can't spot where is something wrong..

The thing is, as long as you're not using GPS your position can be very inaccurate since it's only using the internet and your mobile network information. The accuracy of such measurements can vary greatly, from 10-20 meters up to 2000-3000+ meters. That said, even staying on the same network and in the same location sometimes the accuracy changes and with it your position changes. So you might see your accurate location now, in a few minutes you might be a kilometer away from where you really are on the map. And in case you're using GPS, keep in mind that GPS isn't always available (ie. when you're indoors) and takes some time to start up.
you might want to use only GPS which would make your app unusable in case you're not outside, or you could come up with an algorithm to check if you really are at the new location (use the locations accuracy, time since last location update, or something like that).

android inaccurate gps on google maps v2

1)my android app needs to calculate the accumulate distance when the user press start. when i run, it wait a while then start calculating. which i think may be ok. but when i am not moving, the meters also accumulated by itself.
when i tested it while moving it outside, the blue dot is inaccurate and keeps jumping about. this will makes the distance inaccurate. now i retest i think the red marker is me as it displays the "you are here" one time i tested it. it is all over the place. how do i improve the gps accuracy.
From what it seems, the meters inaccuracy is due to the gps jumping around and not the calculation. i wanted to make a dot follow me and not many markers appearing where i have been..
2)also, i tried displaying this on emulator but failed(googles maps v2). i did install some apk with newely created emulator but failed too. is it illegal even if it works? also i need to display on the same emulator as my team. as a last resort i can display on my phone.
3)to make google maps v2 work on other computer what do i need to do. my research says i need to sign the API key but so far i found are google maps v1 version.
my java file
public class MainActivity extends FragmentActivity implements LocationListener{
protected LocationManager locationManager;
private GoogleMap googleMap;
Button btnStartMove,btnPause,btnResume,btnStop;
static double n=0;
Long s1,r1;
double dis=0.0;
Thread t1;
EditText userNumberInput;
boolean bool=false;
int count=0;
double lat1,lon1,lat2,lon2,lat3,lon3,lat4,lon4;
double dist = 0;
TextView distanceText;
float[] result;
private static final long MINIMUM_DISTANCE_CHANGE_FOR_UPDATES = 0; // in Meters
private static final long MINIMUM_TIME_BETWEEN_UPDATES = 0;
boolean startDistance = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
if(isGooglePlay())
{
setUpMapIfNeeded();
}
distanceText=(TextView)findViewById(R.id.Distance);
btnStartMove=(Button)findViewById(R.id.Start);//start moving
btnStartMove.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View v) {
startDistance = true;
}
});
//prepare distance...........
Log.d("GPS Enabled", "GPS Enabled");
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
String provider = locationManager.getBestProvider(criteria, true);
Location location=locationManager.getLastKnownLocation(provider);
if(location!= null)
{
//Display current location in Toast
String message = String.format(
"Current Location \n Longitude: %1$s \n Latitude: %2$s",
location.getLongitude(), location.getLatitude()
);
Toast.makeText(MainActivity.this, message,
Toast.LENGTH_LONG).show();
//Display current location in textview
//latitude.setText("Current Latitude: " + String.valueOf(location.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(location.getLongitude()));
lat3 = location.getLatitude();
lon3 = location.getLongitude();
}
else if(location == null)
{
Toast.makeText(MainActivity.this,
"Location is null",
Toast.LENGTH_LONG).show();
}
}
private void setUpMapIfNeeded() {
if(googleMap == null)
{
Toast.makeText(MainActivity.this, "Getting map",
Toast.LENGTH_LONG).show();
googleMap =((SupportMapFragment)getSupportFragmentManager().findFragmentById(R.id.displayMap)).getMap();
if(googleMap != null)
{
setUpMap();
}
}
}
private void setUpMap()
{
//Enable MyLocation Layer of Google Map
googleMap.setMyLocationEnabled(true);
//Get locationManager object from System Service LOCATION_SERVICE
//LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
//Create a criteria object to retrieve provider
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_FINE);
//Get the name of the best provider
String provider = locationManager.getBestProvider(criteria, true);
if(provider == null)
{
onProviderDisabled(provider);
}
//set map type
googleMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
//Get current location
Location myLocation = locationManager.getLastKnownLocation(provider);
if(myLocation != null)
{
onLocationChanged(myLocation);
}
locationManager.requestLocationUpdates(provider, 0, 0, this);
}
private boolean isGooglePlay()
{
int status = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (status == ConnectionResult.SUCCESS)
{
Toast.makeText(MainActivity.this, "Google Play Services is available",
Toast.LENGTH_LONG).show();
return(true);
}
else
{
GooglePlayServicesUtil.getErrorDialog(status, this, 10).show();
}
return (false);
}
#Override
public void onLocationChanged(Location myLocation) {
//show location on map.................
//Get latitude of the current location
double latitude = myLocation.getLatitude();
//Get longitude of the current location
double longitude = myLocation.getLongitude();
//Create a LatLng object for the current location
LatLng latLng = new LatLng(latitude, longitude);
//Show the current location in Google Map
googleMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
//Zoom in the Google Map
googleMap.animateCamera(CameraUpdateFactory.zoomTo(20));
googleMap.addMarker(new MarkerOptions().position(new LatLng(latitude, longitude)).title("You are here!"));
//show distance............................
if(startDistance == true)
{
Toast.makeText(MainActivity.this,
"Location has changed",
Toast.LENGTH_LONG).show();
if(myLocation != null)
{
//latitude.setText("Current Latitude: " + String.valueOf(loc2.getLatitude()));
//longitude.setText("Current Longitude: " + String.valueOf(loc2.getLongitude()));
float[] results = new float[1];
Location.distanceBetween(lat3, lon3, myLocation.getLatitude(), myLocation.getLongitude(), results);
System.out.println("Distance is: " + results[0]);
dist += results[0];
DecimalFormat df = new DecimalFormat("#.##"); // adjust this as appropriate
if(count==1)
{
distanceText.setText(df.format(dist) + "meters");
}
lat3=myLocation.getLatitude();
lon3=myLocation.getLongitude();
count=1;
}
}
}
#Override
public void onProviderDisabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider disabled by the user. GPS turned off",
Toast.LENGTH_LONG).show();
}
#Override
public void onProviderEnabled(String provider) {
Toast.makeText(MainActivity.this,
"Provider enabled by the user. GPS turned on",
Toast.LENGTH_LONG).show();
}
#Override
public void onStatusChanged(String provider, int status, Bundle extras) {
Toast.makeText(MainActivity.this, "Provider status changed",
Toast.LENGTH_LONG).show();
}
#Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
#Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER,MINIMUM_TIME_BETWEEN_UPDATES,MINIMUM_DISTANCE_CHANGE_FOR_UPDATES, this);
}}
first screenshot, second after a while in seconds, third after 1 hour about.
at the thrid shot, the screen always return back to the place where there are many red markers and not the blue dot. the toast "location has changed" keeps staying on the screen
the main problem is to ensure accurate distance by ensuring accurate gps. i have been troubled a long time by this, i even take away the map from my application since i can't solve it but now i need it.

To remove the jumping locations, ignore all that have location.getSpeed() < speedThreshold.
Choose a speed threshold according to your app needs, but over 5km/h.
(GPS is inacurate if you stand or move slowly)
Additional Info: see my answer at different-gps-location-reading-of-same-physical-location-on-windows-phone-geocoo