title: Updating previous latitude and longitude
body: <p>Thank you so much for your help, knowledge and time, it is priceless for me. I am working on a GPS location application. The basic idea is the behaviour of a compass. If a walk towards the latitude, so I am going to receive a notification about my direction is going to the north or south and the same with longitude .</p>
  
  <p>Therefore, I have to save the past location known and the current location to compare between them and show the specific notification.  Until now, I am able to recover the current location and the first location, but I can not recover the immediate previous location to compare with the current location. I will have to compare the latitude and longitude between this two points. Consequently, the previous location and actual location have to change according to the movement, but I can only get the updates for the actual location.</p>
  
  <p>I share the source code that I have:</p>
  
  <p>MainActivity.java:</p>
  
  <pre><code>package com.example.locationservicetest;
  
  import android.app.Activity;
  import android.content.Context;
  import android.content.Intent;
  import android.location.Criteria;
  import android.location.Location;
  import android.location.LocationListener;
  import android.location.LocationManager;
  import android.os.Bundle;
  import android.provider.Settings;
  import android.widget.TextView;
  import android.widget.Toast;
  
  public class MainActivity extends Activity {
        TextView latitude;
        TextView longitude;
        TextView prevLatitude;
        TextView prevLongitude;
        TextView provText;
        double   lat1;
        double   lon1;
        LocationManager locationManager;
        String provider;
        MyLocationListener mylistener;
        Criteria criteria;
  
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            latitude = (TextView) findViewById(R.id.lat);
            longitude = (TextView) findViewById(R.id.lon);
            prevLatitude = (TextView) findViewById(R.id.prevLat);
            prevLongitude = (TextView) findViewById(R.id.prevLon);
            provText = (TextView) findViewById(R.id.prov);
  
            //Get the location manager
            locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);          
  
            //Define the criteria how to select the location provider
            criteria = new Criteria();
            criteria.setAccuracy(Criteria.ACCURACY_FINE);   //default
  
            //Charge of data?
            criteria.setCostAllowed(false);
  
            //Get the best provider depending on the criteria
            provider = locationManager.getBestProvider(criteria, false);
  
            //To receive the first location use cached location
            Location location = locationManager.getLastKnownLocation(provider);
            Location mLastLocation;
  
            mylistener = new MyLocationListener();
  
            if (location != null) {
                mylistener.onLocationChanged(location);
                mLastLocation=location;
                lat1=mLastLocation.getLatitude();
                lon1=mLastLocation.getLongitude();
                prevLatitude.setText("Previous Latitude: "+String.valueOf(lat1));
                prevLongitude.setText("Previous Longitude: "+String.valueOf(lon1));
  
            } else {
                //leads to the settings because there is no last known location
                Intent intent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
                startActivity(intent);
            }
            // location updates: at least 1 meter and 200millsecs change
            locationManager.requestLocationUpdates(provider, 200, 1, mylistener);
        }
  
        private class MyLocationListener implements LocationListener {     
            @Override
            public void onLocationChanged(Location location) {
                // Called when a new location is found by the network location provider.
                // Initialize the location fields
                latitude.setText("Latitude: "+String.valueOf(location.getLatitude()));
                longitude.setText("Longitude: "+String.valueOf(location.getLongitude()));
  
                Toast.makeText(getBaseContext(),"Location changed!",
                          Toast.LENGTH_SHORT).show();
            }
  
            @Override
            public void onStatusChanged(String provider, int status, Bundle extras) {
                Toast.makeText(getBaseContext(), provider + "'s status changed to "+status +"!",
                          Toast.LENGTH_SHORT).show();
            }
  
            @Override
            public void onProviderEnabled(String provider) {
                Toast.makeText(getBaseContext(), "Provider " + provider + " enabled!",
                  Toast.LENGTH_SHORT).show();
  
            }
  
            @Override
            public void onProviderDisabled(String provider) {
                Toast.makeText(getBaseContext(), "Provider " + provider + " disabled!",
                  Toast.LENGTH_SHORT).show();
            }
        }
  }
  </code></pre>
  
  <p>Activity_main.xml</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="utf-8"?&gt;
  &lt;LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
      android:layout_width="match_parent"
      android:layout_height="match_parent"
      android:orientation="vertical" &gt;
      &lt;TextView
              android:id="@+id/prov"
              android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:text="No provider selected yet"
              android:layout_marginTop="10dp"
              android:textSize="20dp" /&gt;
      &lt;TextView
              android:id="@+id/lat"
              android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:layout_marginTop="20dp"
              android:text="Latitude: -"
              android:textSize="20dp" /&gt;
      &lt;TextView
              android:id="@+id/lon"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_marginTop="10dp"
              android:text="Longitude: -"
              android:textSize="20dp" /&gt;
      &lt;TextView
              android:id="@+id/prevLat"
              android:layout_width="fill_parent"
              android:layout_height="wrap_content"
              android:layout_marginTop="20dp"
              android:text="PrevLatitude: -"
              android:textSize="20dp" /&gt;
      &lt;TextView
              android:id="@+id/prevLon"
              android:layout_width="wrap_content"
              android:layout_height="wrap_content"
              android:layout_marginTop="10dp"
              android:text="PrevLongitude: -"
              android:textSize="20dp" /&gt;
  &lt;/LinearLayout&gt;
  </code></pre>
  
  <p>Thank you in advance for your kindness</p>