Hi guys! im working with google places and i'm currently able to show 20 markers on the map. I have a FloatingActionButton on my map screen and once the user presses/clicks on it it should display the markers based on the next_page_token. Currently ive hard coded one in for testing and it works but im confused on how to implement it so that when the user clicks on the button then it finds new ones each time.

My Maps class:

package com.example.test.outandabout;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.HashMap;
import java.util.List;

import org.json.JSONObject;

import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.view.View;


import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.GoogleMap.OnInfoWindowClickListener;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;


public class MapsActivity extends FragmentActivity implements LocationListener {

    GoogleMap mMap;
    double mLatitude = 0;
    double mLongitude = 0;
    HashMap<String, String> mMarkerPlaceLink = new HashMap<String, String>();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        // Obtain the SupportMapFragment and get notified when the map is ready to be used.
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mMap = mapFragment.getMap();
        // Enabling MyLocation in Google Map
        mMap.setMyLocationEnabled(true);
        mMap.getUiSettings().setCompassEnabled(true);
        mMap.getUiSettings().setZoomControlsEnabled(true);

        // Getting LocationManager object from System Service
        // LOCATION_SERVICE
        LocationManager locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);

        // Creating a criteria object to retrieve provider
        Criteria criteria = new Criteria();

        // Getting the name of the best provider
        String provider = locationManager.getBestProvider(criteria, true);

        // Getting Current Location From GPS
        Location location = locationManager.getLastKnownLocation(provider);

//        mLatitude = location.getLatitude();
//        mLongitude = location.getLongitude();
//        myLocation = new LatLng(mLatitude, mLongitude);
//
//        mMap.addMarker(new MarkerOptions()
//        .position(myLocation)
//        .title("I'm Here!")
//        .icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_AZURE)));
//        mMap.moveCamera(CameraUpdateFactory.newLatLng(myLocation));

        // onLocationChanged(location);
        if (location != null) {
            onLocationChanged(location);
        }



        StringBuilder sb = new StringBuilder(
                "https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
        sb.append("location=" + mLatitude + "," + mLongitude);
        sb.append("&radius=1000");
        sb.append("&key=API_KEY");
        // Creating a new non-ui thread task to download Google place json
        // data
        PlacesTask placesTask = new PlacesTask();

        // Invokes the "doInBackground()" method of the class PlaceTask
        placesTask.execute(sb.toString());

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab_more);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Finding you some more places!", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();

                StringBuilder sb = new StringBuilder(
                        "https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
                sb.append("pagetoken=xxxxx" );
                sb.append("&key=API_KEY");
                // Creating a new non-ui thread task to download Google place json
                // data
                PlacesTask placesTask = new PlacesTask();

                // Invokes the "doInBackground()" method of the class PlaceTask
                placesTask.execute(sb.toString());

            }
        });

    }


    /**
     * A method to download json data from url
     */
    private String downloadUrl(String strUrl) throws IOException {
        String data = "";
        InputStream iStream = null;
        HttpURLConnection urlConnection = null;
        try {
            URL url = new URL(strUrl);

            // Creating an http connection to communicate with url
            urlConnection = (HttpURLConnection) url.openConnection();

            // Connecting to url
            urlConnection.connect();

            // Reading data from url
            iStream = urlConnection.getInputStream();

            BufferedReader br = new BufferedReader(new InputStreamReader(
                    iStream));

            StringBuffer sb = new StringBuffer();

            String line = "";
            while ((line = br.readLine()) != null) {
                sb.append(line);
            }

            data = sb.toString();
            Log.d("data", "json response: " + data);
            br.close();

        } catch (Exception e) {
            Log.d("Exception while downloading url", e.toString());
        } finally {
            iStream.close();
            urlConnection.disconnect();
        }

        return data;
    }


    /**
     * A class, to download Google Places
     */
    private class PlacesTask extends AsyncTask<String, Integer, String> {

        String data = null;

        // Invoked by execute() method of this object
        @Override
        protected String doInBackground(String... url) {
            try {
                data = downloadUrl(url[0]);
            } catch (Exception e) {
                Log.d("Background Task", e.toString());
            }
            return data;
        }

        // Executed after the complete execution of doInBackground() method
        @Override
        protected void onPostExecute(String result) {
            ParserTask parserTask = new ParserTask();

            // Start parsing the Google places in JSON format
            // Invokes the "doInBackground()" method of the class ParseTask
            parserTask.execute(result);
        }

    }

    /**
     * A class to parse the Google Places in JSON format
     */
    private class ParserTask extends
            AsyncTask<String, Integer, List<HashMap<String, String>>> {

        JSONObject jObject;

        // Invoked by execute() method of this object
        @Override
        protected List<HashMap<String, String>> doInBackground(
                String... jsonData) {

            List<HashMap<String, String>> places = null;
            PlaceJSONParser placeJsonParser = new PlaceJSONParser();

            try {
                jObject = new JSONObject(jsonData[0]);

                /** Getting the parsed data as a List construct */
                places = placeJsonParser.parse(jObject);

            } catch (Exception e) {
                Log.d("Exception", e.toString());
            }
            return places;
        }

        // Executed after the complete execution of doInBackground() method
        @Override
        protected void onPostExecute(List<HashMap<String, String>> list) {

            // Clears all the existing markers
            mMap.clear();
            for (int i = 0; i < list.size(); i++) {

                // Creating a marker
                MarkerOptions markerOptions = new MarkerOptions();

                // Getting a place from the places list
                HashMap<String, String> hmPlace = list.get(i);

                // Getting latitude of the place
                double lat = Double.parseDouble(hmPlace.get("lat"));

                // Getting longitude of the place
                double lng = Double.parseDouble(hmPlace.get("lng"));

                // Getting name
                String name = hmPlace.get("place_name");

                String vicinity = hmPlace.get("vicinity");

                LatLng latLng = new LatLng(lat, lng);

                // Setting the position for the marker
                markerOptions.position(latLng);

                markerOptions.title(name);

                markerOptions.snippet(vicinity);

                // Placing a marker on the touched position
                Marker m = mMap.addMarker(markerOptions);

                // Linking Marker id and place reference

                mMarkerPlaceLink.put(m.getId(), hmPlace.get("reference"));

            }

        }
    }

    @Override
    public void onLocationChanged(Location location) {
        mLatitude = location.getLatitude();
        mLongitude = location.getLongitude();
        LatLng latLng = new LatLng(mLatitude, mLongitude);
        mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng));
        mMap.animateCamera(CameraUpdateFactory.zoomTo(15));

    }

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

    }

    @Override
    public void onProviderEnabled(String provider) {

    }

    @Override
    public void onProviderDisabled(String provider) {

    }
}

And this class is called to get the JSON data:

package com.example.test.outandabout;


import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

public class PlaceJSONParser {



    /** Receives a JSONObject and returns a list */
    public List<HashMap<String,String>> parse(JSONObject jObject){

        JSONArray jPlaces = null;
        try {
            /** Retrieves all the elements in the 'places' array */
            jPlaces = jObject.getJSONArray("results");
        } catch (JSONException e) {
            e.printStackTrace();
        }
        /** Invoking getPlaces with the array of json object
         * where each json object represent a place
         */
        return getPlaces(jPlaces);
    }


    private List<HashMap<String, String>> getPlaces(JSONArray jPlaces){
        int placesCount = jPlaces.length();
        List<HashMap<String, String>> placesList = new ArrayList<HashMap<String,String>>();
        HashMap<String, String> place = null;

        /** Taking each place, parses and adds to list object */
        for(int i=0; i<placesCount;i++){
            try {
                /** Call getPlace with place JSON object to parse the place */
                place = getPlace((JSONObject)jPlaces.get(i));
                placesList.add(place);

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

        return placesList;
    }

    /** Parsing the Place JSON object */
    private HashMap<String, String> getPlace(JSONObject jPlace){

        HashMap<String, String> place = new HashMap<String, String>();
        String placeName = "-NA-";
        String vicinity = "-NA-";
        String latitude="";
        String longitude="";
        String reference="";


        try {
            // Extracting Place name, if available
            if(!jPlace.isNull("name")){
                placeName = jPlace.getString("name");
            }

            // Extracting Place Vicinity, if available
            if(!jPlace.isNull("vicinity")){
                vicinity = jPlace.getString("vicinity");
            }

            latitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
            longitude = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");
            reference = jPlace.getString("reference");


            place.put("place_name", placeName);
            place.put("vicinity", vicinity);
            place.put("lat", latitude);
            place.put("lng", longitude);
            place.put("reference", reference);


        } catch (JSONException e) {
            e.printStackTrace();
        }
        return place;
    }
}

Any help will be appreciated!