如何使用Google Places API搜索地址/地点？ 安卓系统

Question

I want to know how I can use a string to get search results for an address or a place using Google Places API. Currently, I'm using Geocoder to get search results but the results I am getting are not complete or relevant to my current location. Please be a little descriptive because I haven't used Google Places API before. I have read this tutorial but I can't quiet understand it. I will have a string input from the user in an EditText view and I want to use that string to show a list of matching addresses which are relevant to my current location.

Answer 1

Hi here i'm giving you simple example about autocomplete, if you want you can try other from referring google api site. Just follow few steps. Hope this help you to understand and do your work easily

Step 1. In you Activity you need to use edit text as text changed listener, then call places api

    et_Search.addTextChangedListener(new TextWatcher() {

        @Override
        public void onTextChanged(CharSequence s, int start, int before, int count) {

        }

        @Override
        public void beforeTextChanged(CharSequence s, int start, int count,
                                      int after) {
            // TODO Auto-generated method stub
        }

        @Override
        public void afterTextChanged(Editable s) {
            // TODO Auto-generated method stub

                placesTask = new PlacesTask();
                String[] toPass = new String[2];
                toPass[0] = s.toString();
                placesTask.execute(toPass);

        }
    });

Step 2. here is calling for google places api

    // Fetches all places from GooglePlaces AutoComplete Web Service
private class PlacesTask extends AsyncTask<String, Void, String> {

    private String val = "";
    @Override
    protected String doInBackground(String... place) {
        // For storing data from web service
        String data = "";

        // Obtain browser key from https://code.google.com/apis/console
        String key = "key="+getResources().getString(R.string.google_server_key);

        String input="";

        try {
            input = "input=" + URLEncoder.encode(place[0], "utf-8");
        } catch (UnsupportedEncodingException e1) {
            e1.printStackTrace();
        }

        String parameters = input+"&"+key + "&components=country:in";
        // Output format +gpsTracker.getLatitude() + "," + gpsTracker.getLongitude() + "&radius=20000
        String output = "json";

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

        try{
            // Fetching the data from we service
            data = Webservices.ApiCallGet(url);
        }catch(Exception e){
            Log.d("Background Task", e.toString());
        }
        return data;
    }

    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);

        // Creating ParserTask
        parserTask = new ParserTask();

        String[] strData = new String[2];
        strData[0] = result;
        // Starting Parsing the JSON string returned by Web Service
        parserTask.execute(strData);
    }
}

Step 3. Getting Result

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

    JSONObject jObject;

    @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;
    }

    @Override
    protected void onPostExecute(List<HashMap<String, String>> result) {

        String[] from = new String[] { "description"};
        int[] to = new int[] { android.R.id.text1 };
            AutoCompleteAdapter adapter = new AutoCompleteAdapter(getBaseContext(), result);

            // Setting the adapter
            if(adapter != null && result != null )
                lv_SearchList.setAdapter(adapter);

    }
}

// Fetches  latitude & longitude from place id
private class LatLongTask extends AsyncTask<Void, Void, String> {

    private HashMap<String, String> placeMap;
    private ProgressDialog dialog;

    public LatLongTask(HashMap<String, String> placeMap){
        this.placeMap = placeMap;
    }


    @Override
    protected void onPreExecute() {
        super.onPreExecute();
        dialog = ProgressDialog.show(SearchActivity.this, "", "Please Wait...",
                true, false);
    }

    @Override
    protected String doInBackground(Void... place) {
        // For storing data from web service
        String data = "";

        // Obtain browser key from https://code.google.com/apis/console
        String key = "key="+getResources().getString(R.string.google_server_key);

        String input="";

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

        // Building the parameters to the web service
        String parameters = input+"&"+key ;

        // Output format
        String output = "json";

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

        try{
            // Fetching the data from we service
            data = Webservices.ApiCallGet(url);
        }catch(Exception e){
            Log.d("Background Task", e.toString());
        }
        return data;
    }

    @Override
    protected void onPostExecute(String result) {
        super.onPostExecute(result);

        if(dialog!= null && dialog.isShowing()){
            dialog.dismiss();
        }

        try {
            JSONObject jResult = new JSONObject(result);
            if(jResult.getString("status").equals("OK")) {
                JSONObject jsonObject = jResult.getJSONObject("result");
                JSONObject jGeometry = jsonObject.getJSONObject("geometry");
                JSONObject jLocation = jGeometry.getJSONObject("location");
                placeMap.put("lat", ""+jLocation.getString("lat"));
                placeMap.put("lng", ""+jLocation.getString("lng"));
                ArrayList<HashMap<String, String>> mapArrayList = new ArrayList<HashMap<String, String>>();
                mapArrayList.add(placeMap);
                Intent intent = new Intent();
                intent.putExtra("result",  mapArrayList);
                if (getParent() == null) {
                    setResult(Activity.RESULT_OK, intent);
                } else {
                    getParent().setResult(Activity.RESULT_OK, intent);
                }
                finish();
            }else{
                Utils.toastmessage(SearchActivity.this, "Please try again later.");
            }
        } catch (JSONException e) {
            e.printStackTrace();
        }


    }
}

Step 4. create this class

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="";
    String place_id = "";

    try {

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

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

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