An Android Application to Find Determine prescence of water bodies using data from NASA GRACE

MainActivity

package com.hfad.spaceappswater;

import android.content.Context;
import android.content.Intent;
import android.location.Address;
import android.location.Geocoder;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.net.wifi.p2p.WifiP2pManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.*;
import android.widget.*;

import java.io.IOException;
import java.util.List;
import java.util.Locale;

public class MainActivity extends AppCompatActivity{

    private Button location_button = null;
    private TextView location_view = null;
    private Button water_button = null;
    private TextView water_view = null;
    private Spinner water_spinner = null;

    private String latitude = "";
    private String longitude = "";

    private int ltd;
    private int lng;

    private static final String TAG = "MainActivity";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        location_button = (Button)findViewById(R.id.location_button);
        water_button = (Button)findViewById(R.id.water_button);
        location_view = (TextView)findViewById(R.id.location_view);
    }

    private class LocListener implements LocationListener {
        //String elocation = "";

        @Override
        public void onLocationChanged(Location loc) {
            String longitude = "Longitude: " + loc.getLongitude();
            double lng = loc.getLongitude();
            Log.v(TAG, longitude);
            double ltd = loc.getLatitude();
            String latitude = "Latitude: " + loc.getLatitude();
            Log.v(TAG, latitude);

        /*------- To get city name from coordinates -------- */
            String cityName = null;
            Geocoder gcd = new Geocoder(getBaseContext(), Locale.getDefault());
            List<Address> addresses;
            try {
                addresses = gcd.getFromLocation(loc.getLatitude(),
                        loc.getLongitude(), 1);
                if (addresses.size() > 0) {
                    System.out.println(addresses.get(0).getLocality());
                    cityName = addresses.get(0).getLocality();
                }
            }
            catch (IOException e) {
                e.printStackTrace();
            }
            String s = longitude + "\n" + latitude + "\n\nMy Current City is: "
                    + cityName;
            location_view.setText(s);

        }

        @Override
        public void onProviderDisabled(String provider) {}

        @Override
        public void onProviderEnabled(String provider) {}

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

    public void locationClick(View view){
        String text = "Checking Location...";
        int duration = Toast.LENGTH_LONG;

        Toast toast = Toast.makeText(this, text, duration);
        toast.show();

        LocationManager locationManager = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
        LocationListener locationListener = new LocListener();
        try{
        locationManager.requestLocationUpdates(LocationManager.NETWORK_PROVIDER, 5000, 10, locationListener);}
        catch (SecurityException e){
            Log.d(TAG, "Access Denied! Please contact our operator");
        }
    }

    public void waterClick(View view){
        if((latitude.equals(""))||(longitude.equals(""))){
            String text = "Error!!! Location not Checked!!!";
            int duration = Toast.LENGTH_SHORT;

            Toast toast = Toast.makeText(this, text, duration);
        }
        else{
            Intent intent = new Intent(MainActivity.this, MapActivity.class);
            intent.putExtra(MapActivity.EXTRA_LATITUDE, ltd);
            intent.putExtra(MapActivity.EXTRA_LONGITUDE, lng);
            startActivity(intent);
        }
    }

    @Override
    protected void onSaveInstanceState(Bundle savedInstanceState){

    }


}

MapActivity

package com.hfad.spaceappswater;

import android.content.Intent;
import android.graphics.*;
import android.graphics.drawable.*;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.*;

import static java.lang.Math.*;

/**
 * Created by Lenovo on 29/04/2017.
 */

public class MapActivity extends AppCompatActivity {
    public static final String EXTRA_LATITUDE = "Latitude";
    public static final String EXTRA_LONGITUDE = "Longitude";

    private TextView latView = null;
    private TextView lonView = null;
    private TextView resultView = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_map);

        latView = (TextView)findViewById(R.id.lat_view);
        lonView = (TextView)findViewById(R.id.lon_view);

        Intent intent = getIntent();
        double latitude = intent.getDoubleExtra(EXTRA_LATITUDE, 0);
        double longitude = intent.getDoubleExtra(EXTRA_LONGITUDE, 0);
        latView.setText("Latitude : " + latitude);
        lonView.setText("Longitude : " +longitude);

        mapCoordinate(latitude, longitude);
    }

    public void mapCoordinate(double lat, double lon){


        int r1=0, g1=0, b1=0, r2=0, g2=0, b2=0, r3=0, g3=0, b3=0;
        int nlat = (int)round(lat), nlon = (int)round(lon);
        int x = 0, y = 0;

        if(lat<0){
            y = 90-nlat;
        }
        else{
            y = 90-nlat;
        }

        if(lon<0){
            x = 360 + nlon;
        }
        else{
            x = nlon;
        }

        Bitmap bitmap1 = drawableToBitmap(getDrawable(R.drawable.image1));
        Bitmap bitmap2 = drawableToBitmap(getDrawable(R.drawable.image2));
        Bitmap bitmap3 = drawableToBitmap(getDrawable(R.drawable.image3));

        int pixel1 = bitmap1.getPixel(x, y);
        int pixel2 = bitmap2.getPixel(x, y);
        int pixel3 = bitmap3.getPixel(x, y);

        r1 = Color.red(pixel1);
        g1 = Color.green(pixel1);
        b1 = Color.blue(pixel1);
        r2 = Color.red(pixel2);
        g2 = Color.green(pixel2);
        b2 = Color.blue(pixel2);
        r3 = Color.red(pixel3);
        g3 = Color.green(pixel3);
        b3 = Color.blue(pixel3);

        findStatus(r1, g1, b1, r2, g2, b2, r3, g3, b3);
    }

    public static Bitmap drawableToBitmap (Drawable drawable) {
        if (drawable instanceof BitmapDrawable) {
            return ((BitmapDrawable)drawable).getBitmap();
        }

        int width = drawable.getIntrinsicWidth();
        width = width > 0 ? width : 1;
        int height = drawable.getIntrinsicHeight();
        height = height > 0 ? height : 1;

        Bitmap bitmap = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
        Canvas canvas = new Canvas(bitmap);
        drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
        drawable.draw(canvas);

        return bitmap;
    }

    public void findStatus(int r1, int g1, int b1, int r2, int g2, int b2, int r3, int g3, int b3){
        TextView resultView = (TextView)findViewById(R.id.result_view);
        String result = "";
        boolean available = true;

        int r21 = r2 - r1;
        int b21 = b2 - b1;
        int g21 = g2 - g1;
        int r32 = r3 - r2;
        int b32 = b3 - b2;
        int g32 = g3 - g2;

        int ar21 = abs(r21);
        int ab21 = abs(b21);
        int ag21 = abs(g21);
        int ar32 = abs(r32);
        int ab32 = abs(b32);
        int ag32 = abs(g32);

        if((ar21+ab21+ag21)<50){
            if((ar32+ab32+ag32)<50){
                result += "No water available\n";
                available = false;
            }
            else if((ar32+ab32+ag32)<100){
                result += "Water moderately available\n";
            }
            else{
                result += "Water available\n";
            }
        }
        else if((ar21+ab21+ag21)<100){
            result+= "Water moderately available\n";
        }
        else{
            result += "Water available\n";
        }

        if(available==true){
            if(r21>0 && b21<0){
                result += "Water level has decreased significantly";
            }
            else if(r21<0 && b21>0){
                result += "Water level has increased significantly";
            }
            else if(r21<0 && b21<0){
                if(ar21>b21){
                    result+= "Water level has increased slightly";
                }
                else{
                    result+= "Water level has decreased slightly";
                }
            }
            else if(r21>0 && b21>0){
                if(ar21>b21){
                    result+= "Water level has decreased slightly";
                }
                else{
                    result+= "Water level has increased slightly";
                }
            }
            else{
                result+= "Further analysis has to be done";
            }
        }

        resultView.setText(result);
    }
}