MapsActivity.java

package com.survivingwithandroid.weathermap;

import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.TileOverlay;
import com.google.android.gms.maps.model.TileOverlayOptions;
import com.google.android.gms.maps.model.TileProvider;
import com.google.android.gms.maps.model.UrlTileProvider;

import java.net.MalformedURLException;
import java.net.URL;

public class MapsActivity extends FragmentActivity {

    private GoogleMap mMap; // Might be null if Google Play services APK is not available.
    private static String OWM_TILE_URL = "http://tile.openweathermap.org/map/%s/%d/%d/%d.png";
    private Spinner spinner;
    private String tileType = "clouds";
    private TileOverlay tileOver;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        spinner = (Spinner) findViewById(R.id.tileType);

        String[] tileName = new String[]{"Clouds", "Temperature", "Precipitations", "Snow", "Rain", "Wind", "Sea level press."};

        ArrayAdapter<String> adpt = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, tileName);

        spinner.setAdapter(adpt);
        spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }

            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                 // Check click
                switch (position) {
                    case 0:
                        tileType = "clouds";
                        break;
                    case 1:
                        tileType = "temp";
                        break;
                    case 2:
                        tileType = "precipitation";
                        break;
                    case 3:
                        tileType = "snow";
                        break;
                    case 4:
                        tileType = "rain";
                        break;
                    case 5:
                        tileType = "wind";
                        break;
                    case 6:
                        tileType = "pressure";
                        break;

                }

                if (mMap != null) {
                    tileOver.remove();
                    setUpMap();
                }


            }
        });
        setUpMapIfNeeded();
    }

    @Override
    protected void onResume() {
        super.onResume();
        setUpMapIfNeeded();
    }

    /**
     * Sets up the map if it is possible to do so (i.e., the Google Play services APK is correctly
     * installed) and the map has not already been instantiated.. This will ensure that we only ever
     * call {@link #setUpMap()} once when {@link #mMap} is not null.
     * <p/>
     * If it isn't installed {@link SupportMapFragment} (and
     * {@link com.google.android.gms.maps.MapView MapView}) will show a prompt for the user to
     * install/update the Google Play services APK on their device.
     * <p/>
     * A user can return to this FragmentActivity after following the prompt and correctly
     * installing/updating/enabling the Google Play services. Since the FragmentActivity may not
     * have been completely destroyed during this process (it is likely that it would only be
     * stopped or paused), {@link #onCreate(Bundle)} may not be called again so we should call this
     * method in {@link #onResume()} to guarantee that it will be called.
     */
    private void setUpMapIfNeeded() {
        // Do a null check to confirm that we have not already instantiated the map.
        if (mMap == null) {
            // Try to obtain the map from the SupportMapFragment.
            mMap = ((SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map))
                    .getMap();
            // Check if we were successful in obtaining the map.
            if (mMap != null) {
                setUpMap();
            }
        }
    }

    /**
     * This is where we can add markers or lines, add listeners or move the camera. In this case, we
     * just add a marker near Africa.
     * <p/>
     * This should only be called once and when we are sure that {@link #mMap} is not null.
     */
    private void setUpMap() {
       // Add weather tile
       //tileOver = mMap.addTileOverlay(new TileOverlayOptions().tileProvider(createTilePovider()));

        tileOver = mMap.addTileOverlay(new TileOverlayOptions().tileProvider(createTransparentTileProvider()));
    }

    private TileProvider createTransparentTileProvider() {
        return new TransparentTileOWM(tileType);
    }


    private TileProvider createTilePovider() {
        TileProvider tileProvider = new UrlTileProvider(256, 256) {
            @Override
            public URL getTileUrl(int x, int y, int zoom) {
                String fUrl = String.format(OWM_TILE_URL, tileType == null ? "clouds" : tileType, zoom, x, y);
                URL url = null;
                try {
                    url = new URL(fUrl);
                }
                catch(MalformedURLException mfe) {
                    mfe.printStackTrace();
                }

                return url;
            }
        } ;

        return tileProvider;
    }
}