Adding Google Places Autocomplete API as custom suggestions in Android Search Dialog

July 17, 2013
By

In this article, we will develop an Android application with a search dialog box.

The search dialog box allows users to search various places using Google Places API and shows the result as a marker in the Google Maps Android API V2.

We also add custom suggestions to Search Dialog with Google Places Autocomplete api.



Major files used in this application are listed below :

  • MainActivity.java : This is the only activity that the application contains and search is invoked from this activity using options menu.
  • searchable.xml : This is the configuration file for search dialog which defines content provider and suggestion properties.
  • PlaceProvider.java : The content provider for fetching places from Google places autocomplete API.
  • PlaceJSONParser.java : Parses the result of Google Places Autocomplete API.
  • PlaceDetailsJSONParser.java : Parses the result of Google Places Details API.


This application is developed in Eclipse (4.2.1) with ADT plugin (22.0.1) and Android SDK (22.0.1) and tested in real devices with Android versions 2.3.6  ( GingerBread ) and 4.1.2 ( Jelly Bean ).

An alternative to this application is available in “Android SearchView widget with Google Places API using ActionBarSherlock library“, where we have used SearchView widget for searching places.


1. Create new Android application project with the given below details

Application Name : LocationSearchDialogV2

Project Name : LocationSearchDialogV2

Package Name : in.wptrafficanalyzer.locationsearchdialogv2

Minimum Required SDK : API 8 : Android 2.2 ( Froyo )

Target SDK : API 17 : Android 4.2 ( Jelly Bean )


2. Download and configure Google Play Services Library in Eclipse

Please follow the given below link to setup Google Play Service library in Eclipse.

http://developer.android.com/google/play-services/setup.html


3. Referencing the Google Play Services library in this project

Please follow the given below link to reference the Google Play Service library into this project

http://developer.android.com/tools/projects/projects-eclipse.html#ReferencingLibraryProject


4. Get the API key for Google Maps Android API V2

We need to get an API key from Google to use Google Maps in Android application.

Please follow the given below link to get the API key for Google Maps Android API v2.

https://developers.google.com/maps/documentation/android/start


5. Get the API key for Google Places API

We can create API key for Google Place API by clicking “Create new Browser key”  available at the “API Access” pane of the Google console URL : http://code.google.com/apis/console.

Also ensure that, “Places API” is enabled in the “Services” pane of the Google console.


6. Add Android Support library to this project

By default, Android support library (android-support-v4.jar ) is added to this project by Eclipse IDE to the directory libs. If it is not added, we can do it manually by doing the following steps :

  • Open Project Explorer by Clicking “Window -> Show View -> Project Explorer”
  • Right click this project
  • Then from popup menu, Click “Android Tools -> Add Support Library “

7. Update the file res/values/strings.xml


<?xml version="1.0" encoding="utf-8"?>
<resources>

    <string name="app_name">LocationSearchDialogV2</string>
    <string name="action_search">Search</string>
    <string name="hello_world">Hello world!</string>
    <string name="search_hint">Search Places</string>
    <string name="search_settings">Search Places</string>

</resources>


8. Update the layout file res/layout/activity_main.xml


<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingBottom="@dimen/activity_vertical_margin"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context=".MainActivity" >

    <fragment
        android:id="@+id/map"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        class="com.google.android.gms.maps.SupportMapFragment" />

</RelativeLayout>


9. Update the menu file res/menu/main.xml


<menu xmlns:android="http://schemas.android.com/apk/res/android" >

<item
    android:id="@+id/action_search"
    android:orderInCategory="100"
    android:showAsAction="never"
    android:title="@string/action_search"/>

</menu>


10. Create the class file src/in/wptrafficanalyzer/locationsearchdialogv2/PlaceJSONParser.java

package in.wptrafficanalyzer.locationsearchdialogv2;

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("predictions");
        } 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 id="";
        String reference="";
        String description="";

        try {

            description = jPlace.getString("description");
            id = jPlace.getString("id");
            reference = jPlace.getString("reference");

            place.put("description", description);
            place.put("_id",id);
            place.put("reference",reference);

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


11. Create the class file src/in/wptrafficanalyzer/locationsearchdialogv2/PlaceDetailsJSONParser.java

package in.wptrafficanalyzer.locationsearchdialogv2;

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

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

public class PlaceDetailsJSONParser {

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

        Double lat = Double.valueOf(0);
        Double lng = Double.valueOf(0);
        String formattedAddress = "";

        HashMap<String, String> hm = new HashMap<String, String>();
        List<HashMap<String, String>> list = new ArrayList<HashMap<String,String>>();

        try {
            lat = (Double)jObject.getJSONObject("result").getJSONObject("geometry").getJSONObject("location").get("lat");
            lng = (Double)jObject.getJSONObject("result").getJSONObject("geometry").getJSONObject("location").get("lng");
            formattedAddress = (String) jObject.getJSONObject("result").get("formatted_address");

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

        hm.put("lat", Double.toString(lat));
        hm.put("lng", Double.toString(lng));
        hm.put("formatted_address",formattedAddress);

        list.add(hm);

        return list;
    }
}

12. Create the file src/in/wptrafficanalyzer/locationsearchdialogv2/PlaceProvider.java

package in.wptrafficanalyzer.locationsearchdialogv2;

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

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

import android.app.SearchManager;
import android.content.ContentProvider;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.MatrixCursor;
import android.net.Uri;
import android.util.Log;

public class PlaceProvider extends ContentProvider {

    public static final String AUTHORITY = "in.wptrafficanalyzer.locationsearchdialogv2.PlaceProvider";

    public static final Uri SEARCH_URI = Uri.parse("content://"+AUTHORITY+"/search");

    public static final Uri DETAILS_URI = Uri.parse("content://"+AUTHORITY+"/details");

    private static final int SEARCH = 1;
    private static final int SUGGESTIONS = 2;
    private static final int DETAILS = 3;

    // Obtain browser key from https://code.google.com/apis/console
    String mKey = "key=YOUR_BROWSER_KEY";

    // Defines a set of uris allowed with this content provider
    private static final UriMatcher mUriMatcher = buildUriMatcher();

    private static UriMatcher buildUriMatcher() {

        UriMatcher uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);

        // URI for "Go" button
        uriMatcher.addURI(AUTHORITY, "search", SEARCH );

        // URI for suggestions in Search Dialog
        uriMatcher.addURI(AUTHORITY, SearchManager.SUGGEST_URI_PATH_QUERY,SUGGESTIONS);

        // URI for Details
        uriMatcher.addURI(AUTHORITY, "details",DETAILS);

        return uriMatcher;
    }

    @Override
    public Cursor query(Uri uri, String[] projection, String selection,
        String[] selectionArgs, String sortOrder) {
        Cursor c = null;

        PlaceJSONParser parser = new PlaceJSONParser();
        PlaceDetailsJSONParser detailsParser = new PlaceDetailsJSONParser();

        String jsonString = "";
        String jsonPlaceDetails = "";

        List<HashMap<String, String>> list = null;
        List<HashMap<String, String>> detailsList = null;

        MatrixCursor mCursor = null;

        switch(mUriMatcher.match(uri)){
        case SEARCH:
            // Defining a cursor object with columns description, lat and lng
            mCursor = new MatrixCursor(new String[] { "description","lat","lng" });

            // Create a parser object to parse places in JSON format
            parser = new PlaceJSONParser();

            // Create a parser object to parse place details in JSON format
            detailsParser = new PlaceDetailsJSONParser();

            // Get Places from Google Places API
            jsonString = getPlaces(selectionArgs);
            try {
                // Parse the places ( JSON => List )
                list = parser.parse(new JSONObject(jsonString));

                // Finding latitude and longitude for each places using Google Places Details API
                for(int i=0;i<list.size();i++){
                    HashMap<String, String> hMap = (HashMap<String, String>) list.get(i);

                    detailsParser =new PlaceDetailsJSONParser();

                    // Get Place details
                    jsonPlaceDetails = getPlaceDetails(hMap.get("reference"));

                    // Parse the details ( JSON => List )
                    detailsList = detailsParser.parse(new JSONObject(jsonPlaceDetails));

                    // Creating cursor object with places
                    for(int j=0;j<detailsList.size();j++){
                        HashMap<String, String> hMapDetails = detailsList.get(j);

                        // Adding place details to cursor
                        mCursor.addRow(new String[]{ hMap.get("description") , hMapDetails.get("lat") , hMapDetails.get("lng") });
                    }

                }
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            c = mCursor;
            break;

        case SUGGESTIONS :

            // Defining a cursor object with columns id, SUGGEST_COLUMN_TEXT_1, SUGGEST_COLUMN_INTENT_EXTRA_DATA
            mCursor = new MatrixCursor(new String[] { "_id", SearchManager.SUGGEST_COLUMN_TEXT_1, SearchManager.SUGGEST_COLUMN_INTENT_EXTRA_DATA } );

            // Creating a parser object to parse places in JSON format
            parser = new PlaceJSONParser();

            // Get Places from Google Places API
            jsonString = getPlaces(selectionArgs);

            try {
                // Parse the places ( JSON => List )
                list = parser.parse(new JSONObject(jsonString));

                // Creating cursor object with places
                for(int i=0;i<list.size();i++){
                    HashMap<String, String> hMap = (HashMap<String, String>) list.get(i);

                    // Adding place details to cursor
                    mCursor.addRow(new String[] { Integer.toString(i), hMap.get("description"), hMap.get("reference") });
                }
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
            c = mCursor;
            break;

        case DETAILS :
            // Defining a cursor object with columns description, lat and lng
            mCursor = new MatrixCursor(new String[] { "description","lat","lng" });

            detailsParser = new PlaceDetailsJSONParser();
            jsonPlaceDetails = getPlaceDetails(selectionArgs[0]);
            try {
                detailsList = detailsParser.parse(new JSONObject(jsonPlaceDetails));
            } catch (JSONException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            for(int j=0;j<detailsList.size();j++){
                HashMap<String, String> hMapDetails = detailsList.get(j);
                mCursor.addRow(new String[]{ hMapDetails.get("formatted_address") , hMapDetails.get("lat") , hMapDetails.get("lng") });
            }
            c = mCursor;
            break;
        }
        return c;
    }

    @Override
    public int delete(Uri uri, String selection, String[] selectionArgs) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public String getType(Uri uri) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public Uri insert(Uri uri, ContentValues values) {
        // TODO Auto-generated method stub
        return null;
    }

    @Override
    public boolean onCreate() {
        // TODO Auto-generated method stub
        return false;
    }

    @Override
    public int update(Uri uri, ContentValues values, String selection,
        String[] selectionArgs) {
        // TODO Auto-generated method stub
        return 0;
    }

    /** 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();

            br.close();

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

    private String getPlaceDetailsUrl(String ref){

        // reference of place
        String reference = "reference="+ref;

        // Sensor enabled
        String sensor = "sensor=false";

        // Building the parameters to the web service
        String parameters = reference+"&"+sensor+"&"+mKey;

        // Output format
        String output = "json";

        // Building the url to the web service
        String url = "https://maps.googleapis.com/maps/api/place/details/"+output+"?"+parameters;

        return url;
    }

    private String getPlacesUrl(String qry){

        try {
            qry = "input=" + URLEncoder.encode(qry, "utf-8");
        } catch (UnsupportedEncodingException e1) {
            e1.printStackTrace();
        }

        // Sensor enabled
        String sensor = "sensor=false";

        // place type to be searched
        String types = "types=geocode";

        // Building the parameters to the web service
        String parameters = qry+"&"+types+"&"+sensor+"&"+mKey;

        // Output format
        String output = "json";
        // Building the url to the web service
        String url = "https://maps.googleapis.com/maps/api/place/autocomplete/"+output+"?"+parameters;
        return url;
    }

    private String getPlaces(String[] params){
        // For storing data from web service
        String data = "";
        String url = getPlacesUrl(params[0]);
        try{
            // Fetching the data from web service in background
            data = downloadUrl(url);
        }catch(Exception e){
            Log.d("Background Task",e.toString());
        }
        return data;
    }

    private String getPlaceDetails(String reference){
        String data = "";
        String url = getPlaceDetailsUrl(reference);
        try {
            data = downloadUrl(url);
        } catch (IOException e) {
            e.printStackTrace();
        }
        return data;
    }
}

Note : Update “YOUR_BROWSER_KEY on line 39 with the browser key obtained in Step 5.


13. Update the class MainActivity in the file src/in/wptrafficanalyzer/locationsearchdialogv2/MainActivity.java

package in.wptrafficanalyzer.locationsearchdialogv2;

import android.app.SearchManager;
import android.content.Intent;
import android.database.Cursor;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.LoaderManager.LoaderCallbacks;
import android.support.v4.content.CursorLoader;
import android.support.v4.content.Loader;
import android.view.Menu;
import android.view.MenuItem;

import com.google.android.gms.maps.CameraUpdate;
import com.google.android.gms.maps.CameraUpdateFactory;
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;

public class MainActivity extends FragmentActivity implements LoaderCallbacks<Cursor>{

    GoogleMap mGoogleMap;

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

        SupportMapFragment fragment = (SupportMapFragment) getSupportFragmentManager().findFragmentById(R.id.map);
        mGoogleMap = fragment.getMap();

        handleIntent(getIntent());

    }

    private void handleIntent(Intent intent){
        if(intent.getAction().equals(Intent.ACTION_SEARCH)){
            doSearch(intent.getStringExtra(SearchManager.QUERY));
        }else if(intent.getAction().equals(Intent.ACTION_VIEW)){
            getPlace(intent.getStringExtra(SearchManager.EXTRA_DATA_KEY));
        }
    }

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        setIntent(intent);
        handleIntent(intent);
    }

    private void doSearch(String query){
        Bundle data = new Bundle();
        data.putString("query", query);
        getSupportLoaderManager().restartLoader(0, data, this);
    }

    private void getPlace(String query){
        Bundle data = new Bundle();
        data.putString("query", query);
        getSupportLoaderManager().restartLoader(1, data, this);
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onMenuItemSelected(int featureId, MenuItem item) {
        switch(item.getItemId()){
        case R.id.action_search:
            onSearchRequested();
            break;
        }
        return super.onMenuItemSelected(featureId, item);
    }

    @Override
    public Loader<Cursor> onCreateLoader(int arg0, Bundle query) {
        CursorLoader cLoader = null;
        if(arg0==0)
            cLoader = new CursorLoader(getBaseContext(), PlaceProvider.SEARCH_URI, null, null, new String[]{ query.getString("query") }, null);
        else if(arg0==1)
            cLoader = new CursorLoader(getBaseContext(), PlaceProvider.DETAILS_URI, null, null, new String[]{ query.getString("query") }, null);
        return cLoader;
    }

    @Override
    public void onLoadFinished(Loader<Cursor> arg0, Cursor c) {
        showLocations(c);
    }

    @Override
    public void onLoaderReset(Loader<Cursor> arg0) {
        // TODO Auto-generated method stub
    }

    private void showLocations(Cursor c){
        MarkerOptions markerOptions = null;
        LatLng position = null;
        mGoogleMap.clear();
        while(c.moveToNext()){
            markerOptions = new MarkerOptions();
            position = new LatLng(Double.parseDouble(c.getString(1)),Double.parseDouble(c.getString(2)));
            markerOptions.position(position);
            markerOptions.title(c.getString(0));
            mGoogleMap.addMarker(markerOptions);
        }
        if(position!=null){
            CameraUpdate cameraPosition = CameraUpdateFactory.newLatLng(position);
            mGoogleMap.animateCamera(cameraPosition);
        }
    }
}

14. Update the configuration file /res/xml/searchable.xml

<?xml version="1.0" encoding="utf-8"?>
<searchable xmlns:android="http://schemas.android.com/apk/res/android"
    android:label="@string/app_name"
    android:hint="@string/search_hint"
    android:searchSettingsDescription="@string/search_settings"

    android:searchSuggestAuthority="in.wptrafficanalyzer.locationsearchdialogv2.PlaceProvider"
    android:searchSuggestIntentAction="android.intent.action.VIEW"
    android:searchSuggestSelection=" ?"
    android:searchSuggestThreshold="2" >

</searchable>

15. Update the file AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="in.wptrafficanalyzer.locationsearchdialogv2"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="8"
        android:targetSdkVersion="17" />

    <!-- Protect the map component of the application using application signature -->
    <permission
        android:name="in.wptrafficanalyzer.locationsearchdialogv2.permission.MAPS_RECEIVE"
        android:protectionLevel="signature" />

    <!-- Allows to receive map -->
    <uses-permission android:name="in.wptrafficanalyzer.locationsearchdialogv2.permission.MAPS_RECEIVE" />

    <!-- Used by the Google Maps Android API V2 to download map tiles from Google Maps servers -->
    <uses-permission android:name="android.permission.INTERNET" />

    <!-- Allows the Google Maps Android API V2 to cache map tile data in the device's external storage area -->
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />

    <!-- Allows the Google Maps Android API V2 to use WiFi or mobile cell data (or both) to determine the device's location -->
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

    <!-- Allows the Google Maps Android API V2 to use the Global Positioning System (GPS)
    to determine the device's location to within a very small area -->
    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <!-- Allows to contact Google Serves -->
    <uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />

    <!-- Google Maps Android API V2 requires OpenGL ES version 2 -->
    <uses-feature
        android:glEsVersion="0x00020000"
        android:required="true" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name="in.wptrafficanalyzer.locationsearchdialogv2.MainActivity"
            android:label="@string/app_name"
            android:launchMode="singleTop" >

            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>

            <intent-filter>
                <action android:name="android.intent.action.SEARCH" />
            </intent-filter>

            <!-- Points to searchable activity -->
            <meta-data android:name="android.app.default_searchable"
                android:value=".MainActivity" />

            <!-- Points to searchable meta data -->
            <meta-data android:name="android.app.searchable"
                android:resource="@xml/searchable"/>

        </activity>

        <provider
            android:name=".PlaceProvider"
            android:authorities="in.wptrafficanalyzer.locationsearchdialogv2.PlaceProvider"
            android:exported="false" />

        <!-- Specifies the Android API Key, which is obtained from Google API Console -->
        <meta-data android:name="com.google.android.maps.v2.API_KEY"
            android:value="YOUR_ANDROID_API_KEY" />
    </application>
</manifest>

Note : Update “YOUR_ANDROID_API_KEY on line 76 with the android key obtained in Step 4.


16. Screenshots of the application

Showing Search menu on pushing Options Menu

Figure 1 : Showing Search menu on pushing Options Menu

Listing places, as user input place name in Search Dialog

Figure 2 : Automatically refreshes the suggestion list, as user inputs place in Search Dialog

User is selecting a place from suggestion lists

Figure 3 : Selecting a place from suggestion lists

Showing user selected place in Google Maps Android API V2

Figure 4 : Showing selected place in Google Maps Android API V2


17. Download Source Code


How to hire me?

I am George Mathew, working as software architect and Android app developer at wptrafficanalyzer.in

You can hire me on hourly basis or on project basis for Android applications development.

For hiring me, please mail your requirements to info@wptrafficanalyzer.in.

My other blogs
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