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I'm trying to search nearby places such as banks, restaurants, ATMs inside the drawn area on google maps in android

I'm trying to search nearby places such as banks, restaurants, ATMs inside the drawn area on google maps in android. I get coordinates (Latitude and Longitude) in an array, but I'm unable to find nearby places by that array. Can somebody help me? I tried to search but found no results. Great help will be appreciated!

This is my drawn area code:

public class MainActivity extends FragmentActivity implements OnTouchListener {

    private static final String TAG = "polygon";
    private GoogleMap mGoogleMap;
    private View mMapShelterView;
    private GestureDetector mGestureDetector;
    private ArrayList<LatLng> mLatlngs = new ArrayList<LatLng>();
    private PolylineOptions mPolylineOptions;
    private PolygonOptions mPolygonOptions;
    // flag to differentiate whether user is touching to draw or not
    private boolean mDrawFinished = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mMapShelterView = (View) findViewById(R.id.drawer_view);
        mGestureDetector = new GestureDetector(this, new GestureListener());
        mMapShelterView.setOnTouchListener(this);
        initilizeMap();
        //Contains(null);
    }

    private final class GestureListener extends SimpleOnGestureListener {
        @Override
        public boolean onDown(MotionEvent e) {
            return true;
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
                float velocityY) {
            return false;
        }
    }

    /**
     * Ontouch event will draw poly line along the touch points
     * 
     */
    @Override
    public boolean onTouch(View v, MotionEvent event) {
        int X1 = (int) event.getX();
        int Y1 = (int) event.getY();
        Point point = new Point();
        point.x = X1;
        point.y = Y1;
        LatLng firstGeoPoint = mGoogleMap.getProjection().fromScreenLocation(
                point);
        switch (event.getAction()) {

        case MotionEvent.ACTION_DOWN:
            break;

        case MotionEvent.ACTION_MOVE:
            if (mDrawFinished) {
                X1 = (int) event.getX();
                Y1 = (int) event.getY();
                point = new Point();
                point.x = X1;
                point.y = Y1;
                LatLng geoPoint = mGoogleMap.getProjection()
                        .fromScreenLocation(point);
                mLatlngs.add(geoPoint);
                mPolylineOptions = new PolylineOptions();
                mPolylineOptions.color(Color.RED);
                mPolylineOptions.width(3);
                mPolylineOptions.addAll(mLatlngs);
                mGoogleMap.addPolyline(mPolylineOptions);
                **Log.d(TAG, "Latitude and longitude: " + mLatlngs);**

            }
            break;
        case MotionEvent.ACTION_UP:
            Log.d(TAG, "Poinnts array size " + mLatlngs.size());
            mLatlngs.add(firstGeoPoint);
            mGoogleMap.clear();
            mPolylineOptions = null;
            mMapShelterView.setVisibility(View.GONE);
            mGoogleMap.getUiSettings().setZoomGesturesEnabled(true);
            mGoogleMap.getUiSettings().setAllGesturesEnabled(true);
            mPolygonOptions = new PolygonOptions();
            mPolygonOptions.fillColor(0x5500ff00);
           // mPolygonOptions.fillColor(Color.LTGRAY);
            mPolygonOptions.strokeColor(Color.RED);
            mPolygonOptions.strokeWidth(5);
            mPolygonOptions.addAll(mLatlngs);
            mGoogleMap.addPolygon(mPolygonOptions);
            mDrawFinished = false;
            break;
        }
        return mGestureDetector.onTouchEvent(event);
    }

    /**
     * Setting up map
     * 
     */

    private void initilizeMap() {
        int status = GooglePlayServicesUtil
                .isGooglePlayServicesAvailable(getApplicationContext());
        if (status == ConnectionResult.SUCCESS) {
            if (mGoogleMap == null) {
                mGoogleMap = ((SupportMapFragment) getSupportFragmentManager()
                        .findFragmentById(R.id.map)).getMap();
                mGoogleMap.setMyLocationEnabled(true);

            }

        } else if (GooglePlayServicesUtil.isUserRecoverableError(status)) {
            // showErrorDialog(status);
        } else {
            Toast.makeText(this, "No Support for Google Play Service",
                    Toast.LENGTH_LONG).show();
        }
    }

    /**
     * Method gets called on tap of draw button, It prepares the screen to draw
     * the polygon
     * 
     * @param view
     */

    public void drawZone(View view) {
        mGoogleMap.clear();
        mLatlngs.clear();
        mPolylineOptions = null;
        mPolygonOptions = null;
        mDrawFinished = true;
        mMapShelterView.setVisibility(View.VISIBLE);
        mGoogleMap.getUiSettings().setScrollGesturesEnabled(false);
    }

    public synchronized boolean Contains(Location location) {
        boolean isInside = false;

        if (mLatlngs.size() > 0) {
            LatLng lastPoint = mLatlngs.get(mLatlngs.size() - 1);

            double x = location.getLongitude();

            for (LatLng point : mLatlngs) {
                double x1 = lastPoint.longitude;
                double x2 = point.longitude;
                double dx = x2 - x1;

                if (Math.abs(dx) > 180.0) {
                    if (x > 0) {
                        while (x1 < 0)
                            x1 += 360;
                        while (x2 < 0)
                            x2 += 360;
                    } else {
                        while (x1 > 0)
                            x1 -= 360;
                        while (x2 > 0)
                            x2 -= 360;
                    }
                    dx = x2 - x1;
                }

                if ((x1 <= x && x2 > x) || (x1 >= x && x2 < x)) {
                    double grad = (point.latitude - lastPoint.latitude) / dx;
                    double intersectAtLat = lastPoint.latitude
                            + ((x - x1) * grad);

                    if (intersectAtLat > location.getLatitude())
                        isInside = !isInside;
                }
                lastPoint = point;
            }
        }

        return isInside;
    }

I got array on mLatlang ,now I want near by places according to that coordinates not by my current location

Question&Answers:os

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1 Answer

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by (71.8m points)

Here is some working code that uses the Places Web Service API, this should help you get the functionality you're looking for.

General documentation can be found here.

Suported types of Place Types can be found here.

The following is a simple example. First, generate your query string for the API:

public StringBuilder sbMethod() {

    //use your current location here
    double mLatitude = 37.77657;
    double mLongitude = -122.417506;

    StringBuilder sb = new StringBuilder("https://maps.googleapis.com/maps/api/place/nearbysearch/json?");
    sb.append("location=" + mLatitude + "," + mLongitude);
    sb.append("&radius=5000");
    sb.append("&types=" + "restaurant");
    sb.append("&sensor=true");
    sb.append("&key=******* YOUR API KEY****************");

    Log.d("Map", "api: " + sb.toString());

    return sb;
}

Here is the AsyncTask used to query the Places API:

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 ParserTask
        parserTask.execute(result);
    }
}

Here is the downloadURL() method:

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();

        br.close();

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

ParserTask for parsing the JSON result:

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;
        Place_JSON placeJson = new Place_JSON();

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

            places = placeJson.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) {

        Log.d("Map", "list size: " + list.size());
        // Clears all the existing markers;
        mGoogleMap.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");

            Log.d("Map", "place: " + name);

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

            LatLng latLng = new LatLng(lat, lng);

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

            markerOptions.title(name + " : " + vicinity);

            markerOptions.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA));

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

        }
    }
}

Place_JSON class which is used in ParserTask:

public class Place_JSON {

    /**
     * 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;
    }
}

Lastly, invoke the process like this:

    StringBuilder sbValue = new StringBuilder(sbMethod());
    PlacesTask placesTask = new PlacesTask();
    placesTask.execute(sbValue.toString());

Result:

enter image description here


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