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I'm having troubles of getting my current position coordinates using the NETWORK provider of android location system.

Already read a lot of tutorials and implemented 4 or 5 existing classes to my project and all of them are giving me the last coordinates but not the current ones.

I'm pretty sure that the problem is something fundamental that I am missing but I am not able to understand what exactly it is.

Codes I'm using now:

This is my main Activity

package com.example.locationtests;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.TextView;

public class MainActivity extends Activity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    GPSTracker mGPS = new GPSTracker(this);

    TextView text = (TextView) findViewById(R.id.texts);
    if(mGPS.canGetLocation ){
    mGPS.getLocation();
    text.setText("Lat"+mGPS.getLatitude()+"Lon"+mGPS.getLongitude());
    }else{
        text.setText("Unabletofind");
        System.out.println("Unable");
    }
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.main, menu);
    return true;
}

}

This is the class I'm using for Tracking:

package com.example.locationtests;

import android.app.AlertDialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.provider.Settings;
import android.util.Log;

public final class GPSTracker implements LocationListener {

    private final Context mContext;

    // flag for GPS status
    public boolean isGPSEnabled = false;

    // flag for network status
    boolean isNetworkEnabled = false;

    // flag for GPS status
    boolean canGetLocation = false;

    Location location; // location
    double latitude; // latitude
    double longitude; // longitude

    // The minimum distance to change Updates in meters
    private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 1; // 10 meters

    // The minimum time between updates in milliseconds
    private static final long MIN_TIME_BW_UPDATES = 1; // 1 minute

    // Declaring a Location Manager
    protected LocationManager locationManager;

    public GPSTracker(Context context) {
        this.mContext = context;
        getLocation();
    }

    /**
     * Function to get the user's current location
     * 
     * @return
     */
    public Location getLocation() {
        try {
            locationManager = (LocationManager) mContext
                    .getSystemService(Context.LOCATION_SERVICE);

            // getting GPS status
            isGPSEnabled = locationManager
                    .isProviderEnabled(LocationManager.GPS_PROVIDER);

            Log.v("isGPSEnabled", "=" + isGPSEnabled);

            // getting network status
            isNetworkEnabled = locationManager
                    .isProviderEnabled(LocationManager.NETWORK_PROVIDER);

            Log.v("isNetworkEnabled", "=" + isNetworkEnabled);

            if (isGPSEnabled == false && isNetworkEnabled == false) {
                // no network provider is enabled
            } else {
                this.canGetLocation = true;
                if (isNetworkEnabled) {
                    location=null;
                    locationManager.requestLocationUpdates(
                            LocationManager.NETWORK_PROVIDER,
                            MIN_TIME_BW_UPDATES,
                            MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                    Log.d("Network", "Network");
                    if (locationManager != null) {
                        location = locationManager
                                .getLastKnownLocation(LocationManager.NETWORK_PROVIDER);
                        if (location != null) {
                            latitude = location.getLatitude();
                            longitude = location.getLongitude();
                        }
                    }
                }
                // if GPS Enabled get lat/long using GPS Services
                if (isGPSEnabled) {
                    location=null;
                    if (location == null) {
                        locationManager.requestLocationUpdates(
                                LocationManager.GPS_PROVIDER,
                                MIN_TIME_BW_UPDATES,
                                MIN_DISTANCE_CHANGE_FOR_UPDATES, this);
                        Log.d("GPS Enabled", "GPS Enabled");
                        if (locationManager != null) {
                            location = locationManager
                                    .getLastKnownLocation(LocationManager.GPS_PROVIDER);
                            if (location != null) {
                                latitude = location.getLatitude();
                                longitude = location.getLongitude();
                            }
                        }
                    }
                }
            }

        } catch (Exception e) {
            e.printStackTrace();
        }

        return location;
    }

    /**
     * Stop using GPS listener Calling this function will stop using GPS in your
     * app
     * */
    public void stopUsingGPS() {
        if (locationManager != null) {
            locationManager.removeUpdates(GPSTracker.this);
        }
    }

    /**
     * Function to get latitude
     * */
    public double getLatitude() {
        if (location != null) {
            latitude = location.getLatitude();
        }

        // return latitude
        return latitude;
    }

    /**
     * Function to get longitude
     * */
    public double getLongitude() {
        if (location != null) {
            longitude = location.getLongitude();
        }

        // return longitude
        return longitude;
    }

    /**
     * Function to check GPS/wifi enabled
     * 
     * @return boolean
     * */
    public boolean canGetLocation() {
        return this.canGetLocation;
    }

    /**
     * Function to show settings alert dialog On pressing Settings button will
     * lauch Settings Options
     * */
    public void showSettingsAlert() {
        AlertDialog.Builder alertDialog = new AlertDialog.Builder(mContext);

        // Setting Dialog Title
        alertDialog.setTitle("GPS is settings");

        // Setting Dialog Message
        alertDialog
                .setMessage("GPS is not enabled. Do you want to go to settings menu?");

        // On pressing Settings button
        alertDialog.setPositiveButton("Settings",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        Intent intent = new Intent(
                                Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                        mContext.startActivity(intent);
                    }
                });

        // on pressing cancel button
        alertDialog.setNegativeButton("Cancel",
                new DialogInterface.OnClickListener() {
                    public void onClick(DialogInterface dialog, int which) {
                        dialog.cancel();
                    }
                });

        // Showing Alert Message
        alertDialog.show();
    }

    @Override
    public void onLocationChanged(Location location) {
    }

    @Override
    public void onProviderDisabled(String provider) {
    }

    @Override
    public void onProviderEnabled(String provider) {
    }

    @Override
    public void onStatusChanged(String provider, int status, Bundle extras) {
    }

}

This is my AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.locationtests"
    android:versionCode="1"
    android:versionName="1.0" >
    <uses-permission android:name="android.permission.CAMERA" />
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
    <uses-permission android:name="android.permission.INTERNET"></uses-permission>
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" /> 
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <uses-feature android:name="android.hardware.camera" />
    <uses-feature android:name="android.hardware.location" android:required="true" />
    <uses-feature android:name="android.hardware.location.gps" android:required="false" />

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="com.example.locationtests.MainActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

Actually GPS positioning works fine, but NETWORK positioning dosn't. When Ive turned devices GPS on coordinates keep changing while i'm moving, but the same doesn't happen when I have turn it off and relay on the NETWORK_PROVIDER

Chepech
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Boris Pawlowski
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  • check this http://developer.android.com/training/location/retrieve-current.html – OMAK Jul 11 '13 at 10:39
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    The easist way is to use a higher-level library like this: https://github.com/delight-im/Android-SimpleLocation – caw Mar 04 '15 at 22:20
  • there is an easy lib to do so......very easy to implement ..have a look https://github.com/Gaganjdeep/GetMyLocationLIbrary.git OR http://shortcutsandroid.blogspot.in/2016/03/get-current-location-in-activity-in.html – Gagan Mar 10 '16 at 07:11
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    check this out, it is nice and easy https://github.com/meetmehdi/GetAccurateLocation – Syed Raza Mehdi Aug 11 '16 at 13:00
  • @caw Thanks for the direction, now there's no need to reinvent those methods! :) – varun Jul 18 '19 at 13:08

3 Answers3

180

First you need to define a LocationListener to handle location changes.

int LOCATION_REFRESH_TIME = 15000; // 15 seconds to update
int LOCATION_REFRESH_DISTANCE = 500; // 500 meters to update

....

private final LocationListener mLocationListener = new LocationListener() {
    @Override
    public void onLocationChanged(final Location location) {
        //your code here
    }
};

Then get the LocationManager and ask for location updates

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    mLocationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

    mLocationManager.requestLocationUpdates(LocationManager.GPS_PROVIDER, LOCATION_REFRESH_TIME,
            LOCATION_REFRESH_DISTANCE, mLocationListener);
}

And finally make sure that you have added the permission on the Manifest,

For using only network based location use this one

<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>

For GPS based location, this one

<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
GeneCode
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Axxiss
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  • Acctualy GPS possitioning works fine, but NETWORK positioning dosn't. When Ive turned devices GPS on cordinates keep changing while im moving, but dosnt happence same when I have turn it off – Boris Pawlowski Jul 11 '13 at 11:34
  • 9
    Keep in mind that, the precision between GPS and NETWORK based location is really big. Yesterday I was testing in it, while moving on the bus, the GPS gave an accuracy of 3-5 meters and the NETWORK like 1Km. So get in a bus/car and and see the difference between those two. – Axxiss Jul 11 '13 at 11:39
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    @Axxiss how u get LOCATION_REFRESH_TIME, LOCATION_REFRESH_DISTANCE, mLocationListener); – Amitsharma Feb 14 '14 at 07:40
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    @amitsharma those are two constant defined by me. Here you can check the documentation http://developer.android.com/reference/android/location/LocationManager.html#requestLocationUpdates(long, float,android.location.Criteria, android.app.PendingIntent) – Axxiss Feb 14 '14 at 10:56
  • @Axxiss u have tell me before i have dun ,but i have get help from your code thank's Axxiss – Amitsharma Feb 14 '14 at 11:06
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    @Axxiss nice answer :) – Subhan Ali Jul 26 '17 at 10:49
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    You may also need `@Override public void onStatusChanged(String provider, int status, Bundle extras) { } @Override public void onProviderEnabled(String provider) { } @Override public void onProviderDisabled(String provider) { }` – Ege Kuzubasioglu Dec 11 '17 at 10:47
  • What is the difference between network vs gps... which is more accurate? Thanks – Si8 Sep 20 '18 at 12:07
  • God bless your soul @Axxiss – naturesenshi May 07 '19 at 13:23
  • Will this work while in the background? – sshanzel Mar 29 '20 at 10:25
  • how to set accuracy like `PRIORITY_HIGH_ACCURACY` –  Jul 13 '21 at 03:13
12

You need to write code in the OnLocationChanged method, because this method is called when the location has changed. I.e. you need to save the new location to return it if getLocation is called.

If you don't use the onLocationChanged it always will be the old location.

Venky
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Lukas Olsen
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5

I'm using this tutorial and it works nicely for my application.

In my activity I put this code:

GPSTracker tracker = new GPSTracker(this);
    if (!tracker.canGetLocation()) {
        tracker.showSettingsAlert();
    } else {
        latitude = tracker.getLatitude();
        longitude = tracker.getLongitude();
    }

also check if your emulator runs with Google API

fhamicode
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    what is GPSTracker here? – TechArcSri Jun 18 '14 at 10:37
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    flip the if pleassse – pomber Aug 05 '14 at 14:09
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    what is the advantage of flipping the "if"? – drulabs Nov 04 '14 at 14:06
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    @KKD it's clearer to read and it's not a negative check. `if(canGetLocation()){}` sounds much better, doesn't it – Sap Dec 13 '14 at 18:41
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    Never us "true/false" in if statements. If implicitly mean "if it's true or false". – VipulKumar Mar 25 '15 at 05:59
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    @VipulKumar Hi I came cross your answer and I felt that your answer is like paradox. It seems "never use true/false in if statement" is not correct, but still you get two upvotes. I know this answer is one year ago, but can you elaborate the answer in detail? Did I miss something about how to use if? Thanks – fangzhzh Oct 06 '16 at 02:54
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    Hi @fangzhzh, The statement was `tracker.canGetLocation() == false` when I commented. See edit history. It was edited to `!tracker.canGetLocation()`, which is the right way to do it. You should use NOT operator rather than using "false". – VipulKumar Oct 06 '16 at 08:08
  • can u tell me how can i implement the onLocationChanged in your code and further use there values – techDigi Feb 01 '17 at 11:53