Google Places API photo_reference

Question

我一直在尝试提取go​​olge地方api照片参考，但是没有成功。 我想知道是否有人可以帮助我。 下面是我的代码：

// KEY Strings
public static String KEY_REFERENCE = "reference"; // id of the place
public static String KEY_NAME = "name"; // name of the place
public static String KEY_VICINITY = "vicinity"; // Place area name
public static String KEY_PHOTO = "photo_reference";

class LoadPlaces extends AsyncTask<String, String, String> {

    /**
     * getting google places JSON response
     * */

    protected String doInBackground(String... args) {
        // creating Places class object
        googlePlaces = new GooglePlaces();

        try {
            String types = MenuActivity.type;
            String keyword = MenuActivity.keyword;

             // get nearest places
            nearPlaces = googlePlaces.search(gps.getLatitude(),gps.getLongitude(), 
            types, keyword); 

        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    protected void onPostExecute(String file_url) {
        // updating UI from Background Thread

        runOnUiThread(new Runnable() {
            public void run() {
                /**
                 * Updating parsed Places into LISTVIEW
                 * */

                // Get JSON response status
                String status = nearPlaces.status;

                // Check for OK status
                if (status.equals("OK")) {
                    // Successfully got places details
                    if (nearPlaces.results != null) {
                        // loop through each place
                        for (Place p : nearPlaces.results) {
                            HashMap<String, String> map = new HashMap<String, String>();

                            map.put(KEY_REFERENCE, p.reference);
                            map.put(KEY_NAME, p.name);
                            map.put(KEY_PHOTO,p.photo);
                            map.put(KEY_VICINITY, p.vicinity);

                            // adding HashMap to ArrayList
                            placesListItems.add(map);

                        }
                        // list adapter - removed rating
                        ListAdapter adapter = new SimpleAdapter(
                                MainActivity.this, placesListItems,
                                R.layout.list_item, new String[] {
                                KEY_REFERENCE, KEY_NAME, KEY_VICINITY, KEY_PHOTO},
                                new int[] { R.id.reference, R.id.name, R.id.address, R.id.phptp});

                        // Adding data into ListView
                        lv.setAdapter(adapter);
                    }
                } 
}

以下是执行搜索并解析数据的代码：

 public class GooglePlaces {

/** Global instance of the HTTP transport. */
private static final HttpTransport HTTP_TRANSPORT = new NetHttpTransport();
private static final String LOG_KEY = "GGPlace";

// Google API Key
private static final String API_KEY = ""; 

// Google Places serach 
private static final String PLACES_SEARCH_URL = "https://maps.googleapis.com/maps/api/place/nearbysearch/json?&rankby=distance";

private double _latitude;
private double _longitude;
private double _radius;
private String address;

public PlacesList search(double latitude, double longitude, String types, String keyword) 
        throws Exception {

    this._latitude = latitude;
    this._longitude = longitude;

    try {

        HttpRequestFactory httpRequestFactory = createRequestFactory(HTTP_TRANSPORT);
        HttpRequest request = httpRequestFactory.buildGetRequest(new GenericUrl(PLACES_SEARCH_URL));
        request.getUrl().put("key", API_KEY);
        request.getUrl().put("location", _latitude + "," + _longitude);
        request.getUrl().put("sensor", "true");
        if(types != null)
        {
            request.getUrl().put("types", types);
            request.getUrl().put("keyword", keyword);
        }

        PlacesList list = request.execute().parseAs(PlacesList.class);
        // Check log cat for places response status
        Log.d("Places Status", "" + list.status);
        return list;

    } catch (HttpResponseException e) {
        Log.e("Error:", e.getMessage());
        return null;
    }

}
public static HttpRequestFactory createRequestFactory(
        final HttpTransport transport) {
    return transport.createRequestFactory(new HttpRequestInitializer() {
        public void initialize(HttpRequest request) {
            GoogleHeaders headers = new GoogleHeaders();
            headers.setApplicationName("APP NAME");
            headers.gdataVersion="2";
            request.setHeaders(headers);
            JsonHttpParser parser = new JsonHttpParser(new JacksonFactory());
            request.addParser(parser);
        }
    });
}
}

这是我的PlaceList类：

public class PlacesList implements Serializable {
@Key
public String status;

@Key
public List<Place> results;

}

这是我的地方课程：

 public class Place implements Serializable {

@Key
public String id;

@Key
public String name;

@Key
public String reference;

@Key
public String vicinity;

@Key
public Geometry geometry;

@Key
public List<Photo> photos;
}

最后是我的摄影课：

public class Photo implements Serializable {

@Key
public String photo_reference;

@Key
public int height;

@Key
public int width;

}  

我猜我是在错误地致电或传递photo_reference。 我希望那里有人可以帮助我。 我已经为此工作了几周，几乎已经完全放弃了。

Answer 1

嗨，首先，您的搜索网址错误。

您必须遵循以下格式：

https://developers.google.com/places/web-service/photos

请参见下面的完整示例：

http://wptrafficanalyzer.in/blog/showing-nearby-places-with-photos-at-any-location-in-google-maps-android-api-v2/

如果您下载源代码，它将帮助您了解如何在另一个数组中的数组中获取json字符串。

下面的代码段仅回答您必须提取图像的部分：

package in.wptrafficanalyzer.locationnearbyplacesphotos;

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

import android.util.Log;

public class PlaceJSONParser {

    /** Receives a JSONObject and returns a list */
    public Place[] 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 Place[] getPlaces(JSONArray jPlaces){
        int placesCount = jPlaces.length();     
        Place[] places = new Place[placesCount];    

        /** 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 */
                places[i] = getPlace((JSONObject)jPlaces.get(i));               


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

        return places;
    }

    /** Parsing the Place JSON object */
    private Place getPlace(JSONObject jPlace){

        Place place = new Place();



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

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

            if(!jPlace.isNull("photos")){
                JSONArray photos = jPlace.getJSONArray("photos");
                place.mPhotos = new Photo[photos.length()];
                for(int i=0;i<photos.length();i++){
                    place.mPhotos[i] = new Photo();
                    place.mPhotos[i].mWidth = ((JSONObject)photos.get(i)).getInt("width");
                    place.mPhotos[i].mHeight = ((JSONObject)photos.get(i)).getInt("height");
                    place.mPhotos[i].mPhotoReference = ((JSONObject)photos.get(i)).getString("photo_reference");
                    JSONArray attributions = ((JSONObject)photos.get(i)).getJSONArray("html_attributions");
                    place.mPhotos[i].mAttributions = new Attribution[attributions.length()];
                    for(int j=0;j<attributions.length();j++){
                        place.mPhotos[i].mAttributions[j] = new Attribution();
                        place.mPhotos[i].mAttributions[j].mHtmlAttribution = attributions.getString(j);
                    }                   
                }
            }

            place.mLat = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lat");
            place.mLng = jPlace.getJSONObject("geometry").getJSONObject("location").getString("lng");                       



        } catch (JSONException e) {         
            e.printStackTrace();
            Log.d("EXCEPTION", e.toString());
        }       
        return place;
    }
}

Answer 2

我首先误解了photo_reference为Base64编码字符串。 但这并不是从Google Maps API识别和获取照片的参考参数。 将此想象为一个令牌参数。 因此，要获取最大宽度为400的照片，可以使用以下URL。

https://maps.googleapis.com/maps/api/place/photo?maxwidth=400&photoreference=CnRtAAAATLZNl354RwP_9UKbQ_5Psy40texXePv4oAlgP4qNEkdIrkyse7rPXYGd9D_Uj1rVsQdWT4oRz4QrYAJNpFX7rzqqMlZw2h2E2y5IKMUZ7ouD_SlcHxYq1yL4KbKUv3qtWgTK0A6QbGh87GB3sscrHRIQiG2RrmU_jF4tENr9wGS_YxoUSSDrYjWmrNfeEHSGSc3FyhNLlBU&key=YOUR_API_KEY

有关更多详细信息，请访问Google地方信息文档https://developers.google.com/places/web-service/photos