Sample for Android Geo Location

Most Android devices allow to determine the current geolocation.  Below is the sample for Android.

Create Project

Create a new project called de.vogella.android.locationapi.simple with the Activity called ShowLocationActivity.
This example will not use the Google Map therefore, it also runs on an Android device.
Change your layout file from the res/layout folder to the following code.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/linearLayout1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginTop="40dip"
        android:orientation="horizontal" >

        <TextView
            android:id="@+id/TextView01"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:layout_marginRight="5dip"
            android:text="Latitude: "
            android:textSize="20dip" >
        </TextView>

        <TextView
            android:id="@+id/TextView02"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="unknown"
            android:textSize="20dip" >
        </TextView>
    </LinearLayout>

    <LinearLayout
        android:id="@+id/linearLayout2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content" >

        <TextView
            android:id="@+id/TextView03"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="10dip"
            android:layout_marginRight="5dip"
            android:text="Longitute: "
            android:textSize="20dip" >
        </TextView>

        <TextView
            android:id="@+id/TextView04"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="unknown"
            android:textSize="20dip" >
        </TextView>
    </LinearLayout>

</LinearLayout> 

Add permissions

Add the following permissions to your application in your AndroidManifest.xml file
  • INTERNET
  • ACCESS_FINE_LOCATION
  • ACCESS_COARSE_LOCATION

 

 Activity

Change ShowLocationActivity to the following. It queries the location manager and display the queried values in the activity.

package de.vogella.android.locationsapi.simple;

import android.app.Activity;
import android.content.Context;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.widget.TextView;
import android.widget.Toast;

public class ShowLocationActivity extends Activity implements LocationListener {
  private TextView latituteField;
  private TextView longitudeField;
  private LocationManager locationManager;
  private String provider;

  
/** Called when the activity is first created. */
@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); latituteField = (TextView) findViewById(R.id.TextView02); longitudeField = (TextView) findViewById(R.id.TextView04); // Get the location manager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE); // Define the criteria how to select the locatioin provider -> use // default Criteria criteria = new Criteria(); provider = locationManager.getBestProvider(criteria, false); Location location = locationManager.getLastKnownLocation(provider); // Initialize the location fields if (location != null) { System.out.println("Provider " + provider + " has been selected."); onLocationChanged(location); } else { latituteField.setText("Location not available"); longitudeField.setText("Location not available"); } } /* Request updates at startup */ @Override protected void onResume() { super.onResume(); locationManager.requestLocationUpdates(provider, 400, 1, this); } /* Remove the locationlistener updates when Activity is paused */ @Override protected void onPause() { super.onPause(); locationManager.removeUpdates(this); } @Override public void onLocationChanged(Location location) { int lat = (int) (location.getLatitude()); int lng = (int) (location.getLongitude()); latituteField.setText(String.valueOf(lat)); longitudeField.setText(String.valueOf(lng)); } @Override public void onStatusChanged(String provider, int status, Bundle extras) { // TODO Auto-generated method stub } @Override public void onProviderEnabled(String provider) { Toast.makeText(this, "Enabled new provider " + provider, Toast.LENGTH_SHORT).show(); } @Override public void onProviderDisabled(String provider) { Toast.makeText(this, "Disabled provider " + provider, Toast.LENGTH_SHORT).show(); } }

 

 Run and Test

If you using the emulator send some geo-coordinates to your device. These geo-coordinate should be displayed as soon as you press the button.

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