com.capstone.transit.trans_it.PlacesAutoCompleteAdapter.java Source code

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Here is the source code for com.capstone.transit.trans_it.PlacesAutoCompleteAdapter.java

Source

/**
 *
 This file is part of the "Get There!" application for android developed
 for the SFWR ENG 4G06 Capstone course in the 2014/2015 Fall/Winter
 terms at McMaster University.
    
    
 Copyright (C) 2015 M. Fluder, T. Miele, N. Mio, M. Ngo, and J. Rabaya
    
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by
 the Free Software Foundation, either version 3 of the License, or
 (at your option) any later version.
    
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU General Public License for more details.
    
 You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
    
 */

package com.capstone.transit.trans_it;

import android.content.Context;
import android.util.Log;
import android.widget.ArrayAdapter;
import android.widget.Filterable;
import android.widget.Filter;

import org.apache.http.HttpRequest;
import org.apache.http.HttpRequestFactory;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.io.IOException;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLEncoder;
import java.util.ArrayList;

/**
 * Created by Thomas on 3/30/2015.
 */
public class PlacesAutoCompleteAdapter extends ArrayAdapter<String> implements Filterable {

    private ArrayList<String> resultList;
    private static final String LOG_TAG = "ExampleApp";

    private static final String PLACES_API_BASE = "https://maps.googleapis.com/maps/api/place";
    private static final String TYPE_AUTOCOMPLETE = "/autocomplete";
    private static final String OUT_JSON = "/json";

    private static final String API_KEY = "AIzaSyBx_5b2C9zAy0_0Z3siwRgjX59r7iuTn4Q";

    public PlacesAutoCompleteAdapter(Context context, int textViewResourceId) {
        super(context, textViewResourceId);
    }

    @Override
    public int getCount() {
        return resultList.size();
    }

    @Override
    public String getItem(int index) {
        return resultList.get(index);
    }

    @Override
    public Filter getFilter() {
        Filter filter = new Filter() {
            @Override
            protected FilterResults performFiltering(CharSequence constraint) {
                FilterResults filterResults = new FilterResults();
                if (constraint != null) {
                    // Retrieve the autocomplete results.
                    resultList = autocomplete(constraint.toString());

                    // Assign the data to the FilterResults
                    filterResults.values = resultList;
                    filterResults.count = resultList.size();
                }
                return filterResults;
            }

            @Override
            protected void publishResults(CharSequence constraint, FilterResults results) {
                if (results != null && results.count > 0) {
                    notifyDataSetChanged();
                } else {
                    notifyDataSetInvalidated();
                }
            }
        };
        return filter;
    }

    private ArrayList<String> autocomplete(String input) {
        ArrayList<String> resultList = null;

        HttpURLConnection conn = null;
        StringBuilder jsonResults = new StringBuilder();
        try {
            StringBuilder sb = new StringBuilder(PLACES_API_BASE + TYPE_AUTOCOMPLETE + OUT_JSON);
            sb.append("?key=" + API_KEY);
            //sb.append("&components=country:ca");
            sb.append("&input=" + URLEncoder.encode(input, "utf8"));

            URL url = new URL(sb.toString());
            conn = (HttpURLConnection) url.openConnection();
            InputStreamReader in = new InputStreamReader(conn.getInputStream());

            // Load the results into a StringBuilder
            int read;
            char[] buff = new char[1024];
            while ((read = in.read(buff)) != -1) {
                jsonResults.append(buff, 0, read);
            }
        } catch (MalformedURLException e) {
            Log.e(LOG_TAG, "Error processing Places API URL", e);
            return resultList;
        } catch (IOException e) {
            Log.e(LOG_TAG, "Error connecting to Places API", e);
            return resultList;
        } finally {
            if (conn != null) {
                conn.disconnect();
            }
        }

        try {
            // Create a JSON object hierarchy from the results
            JSONObject jsonObj = new JSONObject(jsonResults.toString());
            JSONArray predsJsonArray = jsonObj.getJSONArray("predictions");

            // Extract the Place descriptions from the results
            resultList = new ArrayList<String>(predsJsonArray.length());
            for (int i = 0; i < predsJsonArray.length(); i++) {
                resultList.add(predsJsonArray.getJSONObject(i).getString("description"));
            }
        } catch (JSONException e) {
            Log.e(LOG_TAG, "Cannot process JSON results", e);
        }

        return resultList;
    }
}